CHAPTER 5: SEWAGE TREATMENT PLANT

To protect water resources and the greater environment, all waste from buildings and industrial processes must be treated to meet certain standards of quality. Domestic sewage from dwellings and DWV systems in buildings are permitted to be discharged into the public sewers system, which provides the necessary treatment prior to tits discharge into nature. Water Treatment and Disposal Basic Purposes of sewage treatment

1. To destroy pathogenic micro organisms. Pathogens are disease-causing bacteria.

2. To remove most suspended and dissolved biodegradable organic materials. Raw or untreated sewage is mostly pure water since it comprises about 99.9% water and only about 0.1% impurities. However, sewage contains biodegradable organic material, which is very likely to contain pathogenic micro organisms. The amount of pathogens in the waste water is expected to be proportional to the concentration of fecal coliform bacterium cal E. coli (Escherichia coli). The E. coli concentration in raw sanitary sewage is about 1 billion/ liter, but it is not a pathogen. In fact, our bowels will not function properly without it, but as an indicator organism, the presence of E. coli indicates that water is contaminated with fecal wastes and pathogens maybe present. DENR standard is 10,000 MPN/ 100ml.

• For water to be safe for drinking the E. coli count shall not be more than 1 E. coli per 100ml (about 0.4 cup) of water.

• For water to be considered safe for swimming the E. coli shall be more than 200 E. coli per 100ml of water.

Biological Oxygen Demand (BOD). The measure of the strength of the sewage in relation to the total amount of organic material it contains. Untreated domestic sanitary sewage has an average BOD of about 200mg/ liter. DENR standard is 50 mg/ liter. Total Suspended Solids (TSS). The measure of the strength of the sewage in relation to the total amount of suspended solids. Untreated domestic sanitary sewage has an average TSS of 240 mg/ liter. Another group of impurities that is of major significance in waste water is the compounds of nitrogen (N) and phosphorous (P) from plant nutrients. Raw sanitary sewage contains an average of 35mg/ liter of nitrogen and 10 mg/liter of phosphorous. THE SEWAGE TREATMENT PROCESS

The sewage treatment process may be divided into four major steps:

1. Preliminary treatment. 35% of BOD and 60% of TSS are removed. 2. Primary Treatment, which is subdivided into:

• Sedimentation and retention: raw sewage is retained for the preliminary separation of indigestible solids and the start of aerobic action.

• Aeration: introduction of air through natural convection or mechanical blowers to accelerate the decomposition of organic matters.

• Skimming: Removal of scum that floats on top of the partially treated sewage.

• Sludge Removal: disposal of heavy sludge at the bottom of treated sewage.

In the primary treatment, 85% of BOD and 85% TSS are removed. 3. Secondary Treatment, namely, the removal of colloidal and dissolved organic

material. 4. Tertiary Treatment, that is, the removal of dissolved nitrogen and phosphorous

and disinfection of effluent by the addition of chemicals, such as chlorine (10 mg/liter).

Sewage Treatment Plants The design of sewage treatment plants for large buildings, building complexes and municipalities follows precisely the same processes described above. However, modern treatment plants do require considerable mechanized equipment and controls in order to be efficient and reliable. Sanitary Engineers or Plumbing Engineers who specialized in the subject do the design of these treatment plants. Following are the definitions of some commonly used terms related to the subject of sewage treatment methods and disposal processes:

1. Digestion- That portion of the sewage treatment process in which biochemical decomposition of organic matter takes place, resulting in the formation of simple organic and mineral substances. Also known as aerobic (bacterial) digestion.

2. Influent- Untreated sewage flowing into a treatment system. 3. Effluent- Treated or partially treated sewage flowing out of a treatment system. 4. Sedimentation- Formation of layers of heavy particles in the influent 5. Aerobic (bacterial) digestion- Digestion of the waste through the natural bacteria

digestive action in a tank or chamber. 6. Active Sludge- The sewage sediment, rich in destructive bacteria, which can be

used to break down fresh sewage more quickly. 7. Filtration- a means of filtering out any solid matter from the effluent. 8. Disinfection- A process to disinfect the effluent with chemicals. 9. Percolation- the flow or trickling of a liquid downward through a filtering medium.

A summary of waste water treatment.

CHAPTER 6: PLUMBING MATERIALS DRAINAGE PIPES AND FITTINGS

Drainage pipe. This is the pipe that conveys waste from the building to an approved point of disposal. Drainage Fittings. This are pipe accessories in the drainage system such as a coupling, bend, wye, etc; used to join two or more pipes together or to change their directions. TYPES OF DRAINAGE PIPES

1. Waste pipe 2. Soil pipe 3. Storm pipe 4. Vent pipe

1. Waste pipe. The pipe which carries only liquid waste, free of human excrement

or fecal matter. 2. Soil pipe- the pipe which carries the waste from water closets, urinals or fixtures

of similar function to the building drain. This contains human excrements. 3. Storm pipe- the pipe which convey rainwater from the roof gutter and down

spout to the building storm drain. 4. Vent pipe- the pipe connected to the drainage system that conveys air to and

from the system and keep the water from being siphoned from the trap.

� Branch- is the drainage pipe that runs horizontally. � Stack- is the vertical drainage pipe.

The selection of piping materials for the drainage system depends on the following:

1. Pressure 5. Initial cost 2. Velocity 6. Installation cost 3. Temperature 7. Operating problem 4. Corrosiveness of the medium conveyed within

Common drainage pipes and fittings materials used

a. Asbestos Cement Pipe (ACP) b. Cast Iron Soil Pipe (CISP) c. Concrete pipe d. Vitrified Clay Pipe e. Plastic Pipe

i. Polyethylene (PE) ii. Polyvinyl Chloride (PVC)

iii. Acrylonitrile- Butadiene- Styrene (ABS) f. Iron Pipe Size (IPS)- Iron, Steel, Brass g. Lead

i. Safe spans is 10.56 kg/m2 and 1.6mm thick ii. For flushing or vent terminals- 14.63 kg/ m2 and 1.2 mm thick iii. Lead bends and lead trap shall not be less than 3.2mm in wall thickness.

ASBESTOS CEMENT PIPE This type of pipe is made of asbestos fibers combined under pressure with Portland cement and silica to form a dense and homogeneous material. It is dense cured for strength. TYPES OF ASBESTOS CEMENT PIPE

1. Pressure A.C. Pipe- is used for sewer mains, industrial effluent and process piping, working pressure ranges at 100, 150, and 200 psi.

2. Non-pressure A.C. Pipe- is used for sewer casings for electric cables and as storm drains.

Properties: Diameter: 75mm (3’) to 900 mm (13’) Length: 3.00m (10’) or 4.00m (13’) For 75, 100, 150mm. 4.00m (13’) for 200mm. (8”0 Through 900 mm. (36”) Grades: 1500, 2400, 3000, 4000 and 5000 Lbs/ft. Joints: rubber gasket joint and cement joint

Note: Asbestos cement pipe (ACP) is remarkably suited for embedment in concrete structure since both materials have the same properties. COMMON TYPES OF PIPE FITTINGS

1. Bends (elbows)- are used to complete change of direction in soil, waste and drain lines in horizontal, vertical and diagonal directions.

2. Y (wye) branches- are used for change of direction (diagonal) and branch connections of soil, waste and drain pipes.

3. T (tee) branches- are used to join 3 or 4 pipes at perpendicular directions. CAST IRON SOIL PIPE Cast iron soil pipe (CISP) is made from an alloy of iron, carbon and silicon, with the controlled amounts of manganese, sulfur and phosphorous. This is primarily used for sanitary drain, waste and storm systems. CLASSIFICATIONS OF CAST IRON SOIL PIPE

1. Class A- extra heavy (xh)- is often used for underground applications. 2. Class B- Service weight (SV)- is used for general building installations.

TYPES OF CAST IRON SOIL PIPE

1. Single hub- is equipped with one hub and one spigot end and used in the installation of plumbing in its full length.

2. Double hub- is constructed with a hub on each end so it may be cut into two pieces when a short piece of pipe is needed.

3. Hubless (no hub)- there is no hub on either ends of the pipe, it is used in lieu of the single hub calking of the pipe is difficult.

PROPERTIES

• Available diameter (Nom. I.D.) 2”, 3 ”, 4”, 5”, 6”, 8”, 10”, 12”, 15”

• Hydrostatic Test: 50 psi for service weight 100 psi for extra heavy

• Length: 5’ and 10’

TYPES OF JOINTS FOR CAST IRON SOIL PIPE

1. Lead and Oakum (calk joint) 2. Neoprene Compression gasket 3. Stainless Steel Couplings (for Hubless pipe)

*Oakum- a hemp treated with pitch to make it moisture proof and resistant to the elements contained in the waste. *Calking- plugging an opening with oakum and lead that are pounded into place.

*HUB- that portion of the pipe which, for a short distance, is sufficiently enlarged to receive the end of another pipe of the same diameter for the purpose of making a joint. It is also known as Bell. *SPIGOT- the end of the pipe that fits into a bell or spigot.

FITTINGS FOR CAST IRON SOIL PIPE

CONCRETE PIPE Concrete pipe is cast in metal molds and compacted by tamping or spinning the molds (centrifugal casting). TYPES OF CONCRETE PIPE

1. Non-reinforced concrete pipe- is used for drainage, sewer lines and for gravity-flow water supply lines if the joints are carefully made. Diameters available range from 100mm. (4”) to 900mm (36”).

2. Reinforced concrete pipe (RCP)- is made by the addition of steel wire or steel bars and is primarily used for sewage and storm drainage. Diameters available range from 300mm (12”) to 3600mm (144”)

VITRIFIED CLAY PIPE Vitrified clay pipe is extruded from a suitable grade of shale or clay and fired in kilns producing an extremely hard and dense corrosion resistant material. It is generally used for underground public sewers, house sewers, drainage (sanitary and storm) systems and for industrial wastes such as acids. Vitrified clay pipe is suitable for most gravity-flow systems and is not intended for pressure service. It is brittle and cracks when laid on unstable ground or base.

PROPERTIES *Diameter- 100mm (4”) to 1050 mm (42”) *Grades- standard - extra strength - perforated *Joints - cement joint - pre-fabricated compression seals

VITRIFIED CLAY PIPE FITTINGS

PLASTIC PIPES Plastic pipe is available in compositions designed for various applications including drain, waste and vent. (DWV) BASIC TYPES OF PLASTIC PIPE

1. Thermosel Plastic- has the property of being permanently rigid. Epoxy and fiber glass are example of this.

2. Thermo Plastic- is a material having the property of softening when heated and hardening when cooled.

TYPES OF PLASTIC PIPES FOR DRAINAGE SYSTEM

1. Polyethylene (PE)- the high density P.E. spiral pipe (HDPE) is used as drainage and sewer pipe for housing complex, playground, golf course, industrial farm and stock farm.

It is sufficiently flexible to follow ground contours of snake around obstacles.

HIDE PIPE FITTINGS

2. Polyvinyl Chloride (PVC)- is a thermoplastic type which is composed of molecules of polymers. Each molecule is a long chain made of carbon, hydrogen and other atoms which are melted down and molded.

HDPE SPIRAL PIPE Properties *Diameter- 100mm (4’) to 900mm (36”) *Color- black *Joint- Screw-type couplings *Brand- Atlanta

TYPES OF PVC PIPES USED FOR DRAINAGE

1. uPVC Sanitary pipes (unplasticized)- (DWV) is designed for above and underground sanitary piping system. It is ideal for drain, waste and vent installation.

2. uPVC Sewer Pipe- can be used for main sewer system and other underground waste piping system which requires big diameter pipes.

CHAPTER 7: BASIC PLUMBING TOOLS FOR DRAINAGE PIPES AND FITTINGS

THE COMMON TOOLS USED IN THE DRAINAGE PIPES AND FIITINGS ARE:

1. Hacksaw 2. Closet auger 3. Plunger 4. Rule 5. Blow torch 6. Lead pot 7. Pouring ladle 8. Joint runner 9. Ball peen hammer 10. Cold chisel 11. Caulking irons 12. Soldering copper 13. Tin snip 14. Plumb bob 15. Plumb level 16. File

Blow Torch- this is used as a source of heat when melting lead and heating the soldering copper for calk joint.

Rule/ Push-pull tape. This is used to measure pipes to be cut and for measuring the run of the pipes.

Lead Pot. This is used as a vessel for holding lead to be melted. This is also known as Melting Pot.

Pouring Ladle- this is used for scooping up melted lead to be poured into cast iron soil pipes to make a calk joint.

Hacksaw. This is used for cutting pipes.

Joint runner. This is used to close the gap between the hub and the spigot of a cast iron soil pipe while molten lead is poured into the joint of a horizontal pipe run. This is also known as Pouring rope.

Ball Peen hammer- this is used for caulking.

Closet Auger. This is used for removing clogs in drain pipes, usually at water closet, urinal and lavatory stoppage.

Gold chisel- this is used for cutting cast iron pipes and for boring holes.

CHAPTER 8: WATER SUPPLY SOURCES Providing water in buildings is one of the most critical utility requirements. A building without water supply is unfit for human habitation. Generally speaking, potable water is supplied from a local utility through a public water system. For buildings without public water system, an alternative source of water must be considered, such as springs, wells and rain water.

Plunger. This is used to clear the trap at floor drains, or minor obstructions through a pumping action. This is also known as Plumber’s friend or Plumber’s helper.

Calking Iron- this is used for caulking oakum and lead for bed and spigot joints.

Tin snip. This is used for cutting G.I. sheets for straps to anchor pipes.

Soldering Copper. This is used for soldering lead on flashing of vent pipes on G.I. Roofing.

Plumb Level. This is used to establish and guide grades on horizontal drain pipe runs.

File. This is used to remove the burrs of cut pipes.

Plumb Bob. This is used for establishing vertical runs for pipes.

SPRING WATER SOURCE In most conditions, springs are shallow wells with water supply just a few meters from the ground surface. If this is the source of domestic water supply, careful attention must be given to yield and purify. The flow may stop during dry season or surface water may get contaminated. Spring water can be developed so as to secure maximum protection from contamination by excavating sufficiently to locate the true spring openings and to insure a secure foundation for the encasing structure. This structure is known as a spring box which serves as a collector for spring water. Water collected from the spring box flows to a larger storage tank and then to the distribution pipes. The determination of the yield of the spring water source employs a very simple procedure. They are as follows:

1. Channel the flow of the spring into a collection basin. Make sure that the basin collects all available flow.

2. Place an overflow pipe through the dam so that the collected water flows freely through the pipe. There should be no leakage around the pipe.

3. Put a bucket of known volume (for example, a 10-liter bucket) under the overflow pipe to catch the flow.

4. With a watch, measure the amount of time it takes to fill the bucket. At this instance, the rate of flow can be determined.

5. Check the rate of flow per day if it is sufficient to supply the daily water demand of the occupants.

SAMPLE PROBLEMS (DETERMINATION OF SPRING YIELD) It takes a spring 60 seconds to fill a 10-liter bucket. Determine if its daily yield is sufficient to the water demand of the community of 200 people. The average daily water consumption per person is 60 liters. Solution:

� Determine the rate of flow ( in liters/ second)

Rate of Flow= 10 liters = 0.16 liters/ second 60 seconds

� Determine the daily yield ( liters/day)

Daily yield= 0.16 liter x 60 seconds x 60 minutes x 24 hours Second 1 minute 1 hour 1 day = 13, 824 liters per day

� Determine total daily water demand

Total demand= 200 persons x 60 liters/ person / day = 12,000 liters per day

Therefore, the spring with the daily flow of 13,824 liters can sufficiently meet the demand of the community of 200 people. WELLS Wells are holes or shafts sunk into the earth to obtain water from an aquifer. An aquifer is a water-bearing formation of gravel, permeable rock or sand that is capable of providing water, in usable quantities, to springs or wells. The design and proper construction of a well require scientific knowledge of hydrogeology, common sense and practical experience. The types of wells generally refer to the method of its construction, which are:

1. Dub 2. Bored 3. Driven 4. Drilled

a. Percussion or standard b. Rotary c. Reverse-circulation rotary d. Jetting

1. Dug wells- These are wells 60 centimeters or more in diameter dug through

the soft upper soil. The sides may be of masonry or concrete to prevent from caving-in. It is necessary that the well should be impervious to a depth of at least 3 meters.

2. Bored wells – these are constructed using either hand or power driven earth

auger. A well casing is lowered to the bottom of the hole. After the boring is complete, cement grout is poured to fill the gap between the bored hole and the well casing. This is to prevent contamination.

3. Driven wells- a driven well is done by forcing into the earth a 60 to 90

centimeter long piece of perforated steel tube attached to a pointed screen called a “drive point”. This type of well varies from 32 mm diameter at a depth of 3 to 12 meters.

4. Drilled Wells- A drilling rig is used to drill the well hole and then a casing or

tubular pipe is forced down the hole to prevent it from caving-in. when a water-bearing stratum of sufficient capacity is found, a well screen is set in place to permit the water to flow into the casing and to hold back the fine material. The depth of this well is limited

only by the distance one must dig to obtain an adequate supply of fresh water, even down to 450 meters. RAIN WATER SOURCE In terms of resource conservation, rainwater is an attractive alternative. Rain water is soft and is near to the purest state in the hydrological cycle. However, air pollution causes rainwater to be acidic which corrode non-ferrous pipes and cause rusting and clogging of steel pipes. In spite of these conditions, rainwater collection system remains a viable water source alternative. This system typically employ a cistern or covered reservoir tanks to store water collected from roofs or other relatively clean, impervious surfaces. The collected rain can be used for flushing water closets and urinals, as well as for landscape purposes wherein potable water is not necessary. The city council of Cebu promulgated City Ordinance No. 1711 otherwise known as the “water conservation and Flood Prevention ordinance”. This ordinance requires all projects to provide a permanent rainwater tank or container proportionate to the roof area. These are stated as follows:

A. For commercial, Industrial and Institutional buildings

One cubic meter of tank/ container for every fifteen (15) square meters of roof area and deck, up to a maximum of seven (7) cubic meters.

B. For Residential Buildings (Php 500,000.00 and above project cost)

One cubic meter of tank/ container for every fifteen (15) square meters of roof area and deck, up to a maximum of three (3) cubic meters.

SIZING OF RAIN WATER CISTERN There are two methods that can be used in determining the size of the storage tank for rain water:

1. The use of Cebu city Ordinance 1711 which states that for every fifteen (15) square meter of roof area, one (1) cubic meter of rain water can be collected. This is the short method of sizing the cistern.

2. The use of the rain fall data of the locality. This is the long method of determining the size of the cistern.

SAMPLE PROBLEM1: SIZING OF RAINWATER CISTERN BY LOCAL RAINFALL DATA

As part of the design problem, it was required that 5 water closets, 2 urinals and 2 slop sinks of a school building in Cebu city be provided with an alternative source of water supply, specifically from rainfall catchment. Your are to determine the size of the rainwater cistern based on the following givens or assumptions:

1. Water closets shall be flush tank types 2. Rainfall data of Cebu is available from PAGASA 3. Roof area is 1,000 square meter. 4. Capacity of cistern to satisfy 30 minute duration of water demand 5. Rainfall catchment efficiency is 80%.

Solution

1. Solving for rainwater demand load

Water closet: 5 x 5 WSFU = 25 Urinal : 2 x 5 WSFU = 10 Slop Sink : 2 x 10 WSFU= 20 Total demand= 55 WSFU

� From tables of valves, the equivalent for 55 WSFU is 29 GPM � The estimate daily demand is:

Daily demand = 29 gallons x 30 mins. = 870 gallons Mins

� The estimated annual demand is:

Annual Demand= 870 gallons/ day x 365 days = 317,550 gallons Or 1,201,926.75 liters

� The estimated average monthly demand is:

1,201,926.75 liters / 12 = 100,160.56 Or 100.16 cubic meters

2. Determining the rain fall data from PAGASA ( average precipitation rate in

millimeters)

January 109.00m July 196.70

February 71.10 August 152.70

March 54.60 September 186.70

April 58.60 October 201.40

May 120.90 November 162.30

June 177.00 December 137.70

Average annual rainfall: 1628.70 mm

3. Solving for the amount of available rain water per month:

Available rain water = monthly rain fall x roof area x 80% Therefore:

Average Monthly supply: 1,302, 960 / 12 = 108,580 liters

4. Add the available rain water cumulatively

January 87,200 liters July 630,320

February 144,080 August 752,480

March 187,760 September 901,840

April 234,640 October 1,062,960

May 331,360 November 1,192,800

June 472,960 December 1,302,960

January 109.00 x 1000 x 0.80 87, 200 liters

February 71.10 x 1000 x 0.80 56, 880

March 54.60 x 800 43,680

April 58.60 x800 46,880

May 120.90 x 800 96,720

June 177.00 x 800 141,600

July 197.70 x 800 157,360

August 152.70 x 800 122,160

September 186.70 x 800 149,360

October 201.40 x 800 161,120

November 162.30 x 800 129,840

December 137.70 x 800 110,160

TOTAL 1,302,960 liters

CHAPTER 9: DOMESTIC COLD WATER SUPPLY Definition The domestic cold water supply of the plumbing system consists of the piping and fittings which supply cold water from the building water supply to the fixtures, such as lavatories, bath, tubs, water closets and kitchen sinks. This is also known as water distribution system. Elements of water Distribution system

1. Water service or house service 2. Water meter 3. Horizontal supply main or distribution main 4. Riser 5. Fixture branches 6. Valves and control 7. Storage tanks

General types of water distribution system

1. Upfeed Distribution system a. Direct b. Pneumatic air-pressure system

2. Down feed distribution system

Materials for Mains, Risers and Branches 1. Galvanized Iron (G.I.) Pipes and fittings, schedule 40- is moderately corrosion

resistant and suitable for mildly acid water. It is connected to its fitting with threaded connections. It is available in diameters form 12 mm (1/2”) to 300 mm (12”) at a length of 6 meters (20 feet).

2. Polyvinyl chloride (PVC) Pipes and fittings, schedule 40- is economy and ease of instruction make it popular, especially on low budget projects.

3. Polybutilyne (PB) pipe 4. Polyethylene (PE) pipe 5. Copper Pipes and Tubing

a. Type K- used primarily for underground water service. It is color-coded in green.

b. Type L- is most popular for use in water supply system. It is color-coded in blue.

c. Type M- it has the thinnest wall and is used where water pressure is not too great. It is color-coded in red.

Fittings A variety of fittings must be used to install the piping in the project. Fittings are accessories usually standardized, used for joining two or more pipes together. Fittings include:

1. Nipple- a short of piece of pipe, threaded on the outside (male threads) at both ends, used to join couplings or other fittings a. Short nipple- below 75mm in length. Also known as shoulder nipple. b. Long nipple- over 75mm in length. c. Close nipple- where threading meet.

2. Couple- a short internally threaded (female thread) at both ends and used to connect two pipes in straight line.

3. Elbow- a pipe fitting having a bend and makes an angle (90o or 45o) between adjacent pipes for a change in direction. It is also known as ell or straight elbow. a. Reducing elbow- Joins two pipes of different diameters at right angle of each

other. When specifying reducer fittings, the bigger diameter is stated first, (followed by the smaller diameter. (example: reducing elbow, 25mm x 20mm)

b. Street elbow- an elbow fitting having a 45o or 90o bend with an inside thread on one end and outside thread on the other. It is also known as service ell or street ell.

4. Tee- a T-shaped pipe fitting that joins 3 or 4 pipes at perpendicular directions. a. Straight tee c. reducing tee b. Straight cross tee d. reducing cross tee

THE WATER DISTRIBUTION SYSTEM ELEMENTS OF WATER DISTRIBUTION SYSTEM

1. WATER SERVICE OR HOUSE SERVICE

2. WATER METER

3. HORIZONTAL SUPPLY MAIN OR DISTRIBUTION MAIN

4. RISERS

5. FIXTURES BRANCHES

6. VALVES AND CONTROLS

7. STORAGE TANKS

SERVICE TAP CONNECTION DETAIL

CORPORATION COCK- a valve screwed into the street water main to supply the house service connection. GOOSE NECK- the part of a pipe curve like the neck of a goose, usually flexible. CURB STOP- A control valve for the water supply of a building, usually placed in case of emergency or should the water supply of the building be discontinued.

WATER CONNECTION DETAIL

WATER METER- a mechanical device used to measure the volume of water passing through a pipe. METER STOP- A valve placed at the street side of the water meter and serves as a controlling device for the building installation.

GENERAL TYPES OF WATER DISTRIBUTION SYSTEM

1. UPFEED DISTRIBUTION SYSTEM a. Direct system b. Pneumatic air-pressure system

2. DOWNFEED DISTRIBUTION SYSTEM

5. Reducer- a pipe coupling with inside threads, having one end with a smaller diameter than the other and used for connecting pipes of different size. Both openings have the same center line.

6. Bushing- a pipe fitting which is threaded on both the inside and the outside and

used to reduce the size of the pipe opening to receive a pipe or fitting of a different size.

7. Plug- is used to close an opening in a fitting. 8. Cap- is used to close the end of a pipe.

9. Union- a three piece pipe fitting used to connect the ends of two pipes, neither of which can be turned. It is also used on pipes that are to be taken down occasionally. Its parts are:

a. Thread piece b. Center piece c. Shoulder piece

10. Flange- a ring shaped plate screwed on the end of a pipe and provided with

holes for bolts, to allow joining the pipe to a similarly equipped adjoining pipe. The resulting joint is a flanged joint.

11. Extension Piece-

VALVES Valves are used to control the flow of water throughout the supply system. The proper location of valves simplifies repairs to the system, fixtures, or equipment being served. There are usually valves at:

a. Risers b. Branches c. And pipes to individual fixture or equipment

• Types of valves 1. Gate valve 2. Globe valve 3. Check Valve 4. Angle valve 5. Ball valve/ stop cock 6. Faucet/ Bibb

TYPES OF PIPE JOINTS

1. Threaded joints- used in Galvanized Iron (G.I.) pipes and fittings. The thread extensions of the G.I. pipe are as follows:

PIPE SIZE THREAD EXTENSION NO. OF THREAD PER 25MM (1”)

6mm (1/4”) 9mm (3/8”) 18

9mm (3/8”) 9mm (3/8”) 18

12mm (1/2”) 12mm (1/2”) 14

19mm (3/4”) 14mm (9/16”) 14

25mm (1”) 17mm (11/16”) 11 ½

32 mm (1 ¼”) 17mm (11/16”) 11½

37mm (1 ½”) 17mm (11/16”) 11½

50mm (2”) 19mm (3/4”) 11½

2. Solder joints- for rigid and flexible copper tubing. 3. Flared joints- for flexible copper tubing. 4. Solvent weld or cement joint for plastic pipe.

NIPPLE- a short piece of pipe, threaded on the outside (male threads) at both ends, used to join couplings or other fittings.

COUPLING- a short internally threaded (female thread) at both ends and used to connect two pipes in a straight line.

TEE- a t-shaped pipe fitting that joins 3 or 4 pipes at perpendicular directions.

REDUCER- a pipe coupling, with inside threads, having one end with smaller diameter than the other and used for connecting pipes of different size. Both openings have the same center line.

ELBOW- a pipe fitting having a bend and makes an angle between adjacent pipes for a change in direction. Also know as ELL

REDUCING ELBOW- joins two pipes of different diameters at right angle of each other. When specifying reducer fittings the bigger is stated first, followed by the smaller diameter. (example: reducing elbow 25mm x 20 mm)

STREET ELBOW- a pipe fitting having 45o and 90o bend with an inside thread on one end and an outside thread on the other. It is also known as SERVICE ELL or STREET ELL

BUSHING- a pipe fitting which is threaded on both the inside and the outside and used to reduce the size of the pipe opening to receive a pipe or fitting of a different size

PLUG- is used to close an opening in a fitting.

CAP- is used to close the end of a pipe

EXTENSION PIECE

UNION- a three piece pipe fitting used to connect the ends of two pipes, neither of which can be turned. It is also used on pipes that are to be taken down Occasionally.

FLANGE- a ring sharped plate screwed on the end of a pipe and provided with holes for bolts; to allow joining the pipe to a similarly equipped adjoining pipe. The resulting joint is a flanged joint.

WATER SUPPLY STORAGE TANKS In the interest of economy and speed in delivery, it is recommended that standard sizes of water supply tanks be used wherever possible.

• Types of Water supply storage tanks 1. Pressure tanks- used for hydro pneumatic water supply systems. These

are most advantageous used where the peak water demand rate is relatively low, such as in small buildings.

2. Gravity tanks- are elevated tanks recommended for large buildings and high peak water demand rates.

• Requirements for Water Supply Tank Design and Construction 1. Tanks should be designed and constructed so as to be:

a. Water tight b. Vermin-proof c. Corrosion resistant d. Capable of withstanding the pressure under which they are to be

operated e. Provided with safe and easy means of access for inspection

2. The capacity of any single tank in or on a building shall not exceed 113,000 liters (30,000 gallons) or 113 cubic meters.

3. Tanks shall not be located over openings in floor and roof construction.

4. Potable water supply tanks for domestic supply and for standpipe or automatic sprinkler systems shall be designed and installed to furnish water in sufficient quantity and pressure for such systems.

5. The gravity tanks shall be provided with the following pipes: a. Intel Pipe- located not less than 100mm (4”) above the top of the

overflow pipe. b. Overflow Pipe- shall be at least one pipe size larger than the inlet pipe

and not less than the sizes given in Table 1. Overflow pipe shall discharge above and within 150mm (6”) of a roof or catch basin.

c. Emptying Pipe- shall be located and arranged so as to prevent damage from water discharged. Sizes shall be in accordance to the sizes given in Table 2.

d. Outlet Pipe- connected to the down feed pipe and sized according to the water demand.

e. Air vent pipe- shall be provided with durable screens of not less than 100 mesh.

Table 1. Sizes of Overflow Pipes

TANK CAPACITY SIZE OF OVERFLOW PIPE

Liters Gallons mm inches

0 - 2,842 0 - 750 25 1

2,843 – 5,684 751 – 1,500 37 1 ½

5,685 – 11,369 1,501 – 3,000 50 2

11,370 – 18,948 3,001 – 5000 62 2 ½

18,949 – 28,421 5,001 – 7,500 75 3

Over 28,421 More than 7,500 100 4

TANK CAPACITY SIZE OF EMPTYING PIPE

Liters Gallons mm Inches

0 – 18,948 0 – 5,000 62 2 1/2

18,949 – 36,895 5,000 – 10,000 72 3

Over 36,896 More than 10,000 100 4

SIZING OF GRAVITY TANKS Tanks storage capacity required for domestic water supply should be based upon the peak demand load on the water supply system and should be adequate to satisfy that demand for at least 30 minutes. METHOD 1. Using Load Values (WSFUs) Assigned to Fixtures The water supply fixture unit (WSFU) is a factor so chosen that the load producing effects of different kinds of fixtures and their conditions of service can be

expressed as multiples of that factor. As an aid in this regard, tabulated values to given loads in water supply fixture units are shown in Tables 3 and 4. Table 3. Demand Load of Fixtures in Water Supply Fixture Units

FIXTURE TYPE WSFU

Private Public

Bathtub 2 4

Bidet 2 4

Drinking Fountain 1 2

Kitchen Sink 2 4

Lavatory 1 2

Laundry Tray 2 4

Shower (Each head) 2 4

Service sink 2 4

Urinal - 5

Water Closet (Flush Tank) 3 5

Water Closet (Flush valve) 6 10

Note: In estimating demand for water closet, use the value for flush value type. Table 4. Estimating Demand

SUPPLY SYSTEMS PREDOMINANTLY FOR FLUSH TANKS

SUPPLY SYSTEMS PREDOMINANTLY FOR FLUSH VALVES

Loads, WSFU Demand, GPM Load, WSFU Demand, GPM

6 5

8 6.5

10 8 10 27

12 9.2 12 28.6

14 10.4 14 30.2

16 11.6 16 31.8

18 12.8 18 33.4

20 14 20 35

25 17 25 38

30 20 30 41

35 22.5 35 43.8

40 24.8 40 46.5

45 27 45 49

50 29 50 51.5

60 32 60 55

70 35 70 58.8

80 38 80 62

90 41 90 64.8

100 43.5 100 67.5

120 48 120 72.5

140 52.5 140 77.5

160 57 160 52.8

180 61 180 87

200 65 200 91.5

225 70 225 97

250 75 250 101

275 80 275 105.5

300 85 300 110

400 105 400 126

500 125 500 142

750 170 750 178

1000 208 1000 208

1250 240 1250 240

1500 267 1500 267

1750 294 1750 294

2000 321 2000 321

2250 348 2250 348

2500 375 2500 375

2750 402 2750 402

3000 432 3000 432

4000 525 4000 525

5000 593 5000 593

6000 643 6000 643

7000 685 7000 685

8000 718 8000 715

9000 745 9000 745

10000 769 10000 769

SAMPLE PROBLEM: Determine Capacity of Tank by WSFU Values Determine the capacity of the storage tank of a school building with the following fixtures:

45 water closets 4 showers 40 lavatories 18 slop sinks 14 urinals 16 drinking fountains 9 kitchen sinks Solution

1. Determine the demand load (refer to Table 3)

Water closet 43 x 10 430 WSFU

Lavatory 40 x 2 80

Urinal 14 x 5 70

Kitchen sink 9 x 4 36

Shower 4 x 4 16

Slop sink 16 x 5 80

Drinking Fountain 6 x 2 12

Demand Load 728 WSFU

2. Estimate the demand in gallons per minute (refer to Table 4) from Table 4. The

estimated demand for 724 WSFU is 175 GPM. 3. Estimate capacity of the storage tank.

Assume 1 hour as the duration that will adequately satisfy demand. Capacity = 175 gallons x 1 hour (60 mins) Mins = 10,500 gallons

4. Determine the volume of tank

*Use 1 cubic meter= 264 gallons V= 10,500 G 264 V= 39.77 cubic meter Say: 40 cubic meter

MODEL CWT

VOL. M3

DIMENSION m/m

PIPE CONNECTION (A)

WGT. KGS

D H f S O d RP F1 F2 F3 F4 N

500 0.5 992 1265 20 20 20 20 - - 652 864 19 8 40

1000 1.0 1322 1695 25 25 25 25 185 - 652 864 19 8 36

1500 1.5 1597 2145 40 40 40 40 185 - 917 1126 19 8 91

2000 2.0 1641 2060 40 40 40 40 210 - 955 1245 25 8 137

3000 3.0 1877 2170 40 40 40 40 225 - 1043 1345 25 8 164

5000 5.0 2180 2660 50 50 50 50 310 1102 1303 1595 25 16 227

6000 6.0 2300 2780 50 50 50 50 310 1102 1303 1595 25 16 235

10000 10.0 2800 3150 65 65 65 65 325 1510 1715 2010 38 16 420

20000 20.0 3300 3770 65 65 65 65 325 1877 2077 2415 44 16 750

METHOD 2. Using occupant load of the building. This method provides for the design population with the assigned average daily water consumption for various buildings and other facilities. Table 5. Estimated Water Supply Demands

OCCUPANCY AVERAGE DEMAND (GPD per occupant)

PEAK DEMAND (GPM per occupant)

Assembly, Theaters ,Lecture Halls 5 seats + employees 0.17

Churches, Mosques, Synagogues 5 0.12

Factories: No Showers 15 0.12

Factories: with showers 25 0.50

Hospitals 15 0.50

Hotels, Motels 75 0.43

Offices, Stores, Airports, Bus Terminals

10 (add 5 for food service)

0.09

Residences, Homes, Apartments 100 0.33

Restaurants: Dinner only 2 0.15

Restaurants: 2 meals/ day 35 0.13

Restaurants: 3 meals/ day 50 0.13

Schools: with food service 25 0.12

Schools: with gym and showers 30 0.40

Formula: Solving for estimated average water demand in a building BAWD = N x OAWD [1 + 0.00077 (Td-65)] + S Where BAWD = Average water demand of building in gallons/day N = Number of occupants in building OAWD = average water demand per occupant in gallons/day Td = summer design temperature in oF (use the value= 89.6 oF) S = Average or peak demand of any special loads Formula: Solving for Peak water demand in a building BPWD = N x OPWD [1 + 0.00115 (Td-65)] + S Where BPWD = Peak water demand of building in gallons/ minute

OPWD = Peak water demand per occupant in gallons/ minute SAMPLE PROBLEM: Determining Capacity of Tank by Occupant Load Determine the capacity of the storage tank of a school building with an estimated student population of 1,500 people. Assume 25% of the population as daily users of the building. Solution

1. Solve for estimated average water demand in the school BAWD = N x OAWD [1 + 0.00077 (Td-65)] + S = 1500 (0.25) x 25 [1 + 0.00077 (89.6 – 65)] + 0 = 375 x 25.47 BAWD = 9,551.25 gallons per day (Use this value for the tank capacity)

2. Solve for the peak water demand in the school

BPWD = N x OPWD [1 + 0.00115 (Td-65)] + S = 1,500 (0.25) x 0.12 [1 + 0.00115 (89.6 – 65)] = 375 x 0.12 BPWD = 45 gallons per minute

3. Solve for Volume of Tank. *1 cu. Meter= 264 gallons V= 9,551.25 264 V= 36.18 cu.m. Say: 37 cu.m.

TOOLS FOR SUPPLY PIPING WORKS

1. Pipe vise 8. Strap wrench 2. Pipe cutter 9. Pipe tong/ chain wrench 3. Pipe reamer 10. Basin wrench 4. Pipe stock and die 11. Open end wrench 5. Pipe tap 12. Adjustable wrench 6. Pipe wrench 13. Flaring tool 7. Monkey wrench

WATER SUPPLY PIPE TESTS

All piping of the potable water supply system should be proved watertight by the application of the water pressure test, using potable water, so as to disclose leaks and defects. It is recommended that all potable water supply piping inside buildings should be tested, prior to covering or concealment and before fixtures and faucets are installed.

1. Rough Piping Testing- Installation is subjected to a hydrostatic test at 862 kPa (120 psig) minimum for a period of 3 hours and should be proved watertight without any loss of pressure.

2. Finished Piping Testing- The entire completed system, including all fixtures and faucets, should be subjecting it to a hydrostatic test of 517kPa (75 psig) for a period of 3 hours and should be proved watertight without any loss of pressure.

DISINFECTION METHODS Disinfection of newly installed potable water supply systems, including water supply tanks is required to remove objectionable matters in order to correct an unsanitary condition.

• Procedure 1. All water supply connections should be disconnected, plugged or

effectively shut off to prevent any foreign matter or contamination from entering the water supply thereto.

2. For disinfection, on of the following methods may be applied: a. The systems, or part thereof, shall be filled with a water solution

containing 50 parts per million (PPM) of available chlorine and allowed to stand for 24 hours before flushing and returning to service.

b. The system, or part thereof, shall be filled with a water solution containing 200 parts per million (PPM) of available chlorine and allowed to stand for 3 hours before flushing and returning to service.

BASIC PLUMBING TOOLS FOR SUPPLY PIPES AND FITTINGS

PIPE VISE- This is used to hold pipe to be cut, threaded or assembled.

1. PIPE VISE 2. PIPE CUTTER 3. PIPE REAMER 4. PIPE STOCK AND DIES 5. PIPE TAP 6. PIPE WRENCH 7. MONKEY WRENCH 8. STRAP WRENCH 9. PIPE TONG/ CHAIN WRENCH 10. BASIN WRENCH 11. OPEN- END WRENCH 12. ADJUSTABLE WRENCH 13. FLARING TOOL

PIPE CUTTER- this is used for cutting G.I. or Copper tubing.

PIPE TAP- This is used for making internal threads in G.I. Pipes.

PIPE WRENCH-this is used to screw pipes into or out of their fittings.

PIPE REAMER- This is used to remove the burrs form the inside of the pipe or to enlarge an opening. Burr- a rough or sharp edge left on metal by a cutting tool, also known ar burl.

STRAP WRENCH- This is used when working with brass or plated pipes and fittings since it does not damage the surfaced being tightened. It is also used in places too small to admit a pipe wrench.

MONKEY WRENCH- this is use to tighten or loosen fittings with parallel sides or hexagonal ends such as nuts, valves and unions.

BASIN WRENCH-

CHAIN WRENCH- This is used for turning pipes usually with 150mm diameter or larger.

FLARING TOOL- This is used to widen the end of a soft metal tubing usually copper, to make a mechanical seal.

PIPE STOCK AND DIES- This is used to make external threads on G.I. Pipes.

ADJUSTABLE WRENCH- this is used the same as that of a monkey wrench.

OPEN-END WRENCH- This is used to pull up flange bolts and nuts.

CHAPTER 10: PUMPS FOR WATER SUPPLY Classification of Pumps

1. Reciprocating Pumps a. Lift pumps b. Piston or plunger pumps c. Deep-well piston pumps

2. Centrifugal Pumps a. Submersible pump

3. Deep-weel jet pumps 4. Hydraulic Rams 5. Hydropneumatic pressure system

1. RECIPROCATING PUMP- a pump which operates with a to- and –fro motion.

a. Lift Pump- the simplest of the reciprocating pumps and consists of a piston moving up and down in a cylinder or barrel. A lift pump cannot be used to raise water above 7.50 to 8.50 meter at a normal atmospheric pressure (101 kPa) due to: - Loss of efficiency in the pump - Friction in the intake pipe - Impossible to obtain a perfect vacuum

b. Piston or Plunger Pump- is a positive displacement reciprocating pump in

which a plunger is driven backwards and forwards, or up and down by a mechanical working head.

ILLUSTRATION

c. Deep-well piston pump- when water is more than 7.5m below the ground,

it is visually necessary to place the pump in or near the water in the well and pump from there. Water is forced up th drop pipe and out into the delivery pipe.

ILLUSTRATION

CHART 1. FAULT FINDING: Reciprocating Pump

Fault Cause Remedy or action

No discharge Not printed Excessive suction lift Air leaks Vapour lock Blockage Deterioration

�Prime. �Reduce static lift, eliminate or reduce friction on suction side with larger pipes. �Check and eliminate air leaks by sealing. Check gland. �Suction lift excessive for fluid temperature. �Check for blockage in suction pipe, foot valve or strainer. Check suction valves. �Check cylinder liner for wear, bucket leathers and valves

Low discharge, low pressure, single-acting

Faulty valves Cylinder liner Bucket leathers Air leaks Excessive back pressure

�Check valves. �Check liner. �Check leathers. Check and rectify. �Check that total discharge head is not excessive.

Excessive noise No oil or contamination Worn bearings, pinion, main gear, gear, shaft eccentric or strap Excessive speed Excessive suction lift Entrained gas or air Worn valves or faulty valve operation;

�Drain and refill �Check for worn parts. �Reduce to maximum specified level. �Reduce suction lift and/or increase pipe size to reduce friction head. �Modify suction pipe position Check valves and springs.

Excessive vibration Undersize piping Cavitation Deterioration Counter balancing

�Fit large pipes to reduce flow velocity. �Check against causes of cavitation. Increase net positive suction head. �Check for and replace worn parts. �Fit extension beams and

increase weight according to the difference in lift load to discharge load, also effected by changing compensating head to larger size to match deep-well cylinder where practicable. Another remedy is to resude speed to gearing. Check motor loading with ammeter.

Centrifugal Pump- a pump with vanes or impellers that rotate inside a close-fitting case draw-in liquid at the center and, by virtue of centrifugal force, throw-liquid out through an opening in the periphery of the case. Unlike the reciprocating pump, a centrifugal pump will not operate unless the casing is full of water.

1. Submersible Pump- is basically a centrifugal pump complete with electric motorrs which are positioned under water in a suitable bored hole that delivers the water to the surface.

• Important considerations for accurate submersible pump selection. 1. Well diameter- indicates the size of pump to be installed. 2. Well depth- indicates the static water level. The vertical distance from the

surface (datum line) to the water level when no water is being pumped. 3. Pumping Water level- the vertical distance from the datum to the water

level when specified capacity is being pumped. 4. Drawdown- vertical distance between pumping and static water levels. 5. Head above datum- indicates the total discharge head (static plus friction)

between datum line and point of measurement. 6. Pump capacity- volume rate flow expressed in cubic meters per hour or

liters per second to be produced by the pump. 7. Pump setting- the nominal vertical distance (in meters) from datum to the

discharge pipe connection at the pump. 8. Water composition- make up of the water to be pumped. 9. Type of drive- specification of the average power source (single phase or

3 phases). 10. Allowable motor overload- percentage of rated motor main plate power (in

kilowatts or horsepower) that will be permitted to be used. CHART 2. FAULT FINDING: Centrifugal Pumps

Fault Cause Remedy of Action

No Discharge Lack of prime Excessive suction lift Excessive Discharge head Speed too low Pump clogged Wrong direction of rotation Air leaks Vapour lock

�Prime pump and suction line, allowing trapped air to escape through bleed vent. �Check suction head. Reduce lift and/or increase pipe size to negate friction head. Check foot valve and suction pipe for obstruction. �Cheack total head. Ensure all valves open. Check piping for blockages. Ensure non-return valves are installed correct way round. �Check that pump revolutions are consistent with recommendations. �Check that impeller is not clogged. �Check pump is rotating in right direction. �Check suction pipe and connection for leaks. Check seal or gland. �Check fluid temperature to ensure that fluid in the suction line is not flashing to vapour when the pressure is reduced.

Low delivery Air leaks/ vapour locks Worn or clogged impeller Incorrect pipe size

�Check and rectify. �Replace and correct. �Check recommendation.

Blockage or constriction Poor suction Wrong pump High fluid viscosity

Increase size reduce friction head. �Check total head etc. �Ask for recommendation. �Check recommendations.

Low Pressure Worn impeller Wrong rotation Flow velocity Unbalanced impeller Faulty bearings/ bent shaft Misalignment Badly installed

�Check and replace. �Check and correct. �Check recommendation. �Increase size to reduce friction head. �Check total head etc. �Ask for recommendation �Check recommendation

Vibration and noise

Cavitation Incorrect rotation Flow velocity Unbalanced impeller Faulty bearings/ bent shaft Misalignment Badly installed

�Check operation conditions, fluid temperature and NPSH. �Check and rectify. �Increase pipe size. Reduce flow. �Check for wear or clogging �Replace if necessary. �Check alignment with prime-mover. �Check mounting for rigidity.

Excessive wear Corrosion Cavitation Abrassive fluid

�Check that pump material and fluid are compatible. �Check operating conditions. �Ask for recommendations.

Heating bearing Running too fast Belts too tight Misalignment Lack of lubricant Distortion

�Check maximum operating speed. �Slacken tension. �Check alignment �Repack with grease or replace. �Bearings too tight.

DEEP WELL JET PUMP. A pump consisting of a revolving impeller in the pump housing which forces water down a pressure line to an ejector assembly below water level. ILLUSTRATION

HYDRAULIC RAM OR RAM PUMP. A pump in which the power generated from flowing in an enclosed pipe is used to raise part of the water to a height above that from which the flow began. ILLUSTRATION: A typical hydraulic ram pump

ILLUSTRATION: A typical Hydraulic Ram Installation

• Definite Conditions Required for Hydraulic Ram to work Effectively

1. The fall (h) must be more than 0.66m, but should not exceed 6m. 2. The drive pipe should be straight and laid to an even grade, and its length should

be 6 to 8 times the available fall. The drive pipe must be long enough to ensure that when the recoil of water takes place more resistance is offeered by te moving water in the drive pipe than by the delivery valve and the water immediately above it.

3. The amount of water available should be at least 10 times the required supply and there must be a get away for the waste water.

4. The height (H) to which the water is to be delivered should not, in general, be more than 6 to 8 times the available fall.

5. As a rule, the diameter of the drive pipe should be at least twice the diameter of the delivery pipe.

• Calculation In calculating for the quantity of water delivered by a hydraulic ram, use the formula: q= Q x h x e H Where: q= Quantity (in liters) delivered from the ram in a given time Q= Quantity (in liters) flowing to the ram in the same time h= Head (in meters) of water on inlet side of ram H= Height (in meters) to which water is raised e= Effeciency of ram

SAMPLE PROBLEM To supply a ram, 200 liters of water per hour are available. The head of the ram is 1.00m and the height to which is raised is 5.00mm if the ram is assumed to have an efficiency of 60%, what quantity of water will be delivered per hour? SOLUTION: q= Q x h x e H = 200 x 1 x 0.6 5 q= 24 liters per hour

HYDROPNEUMATIC PRESSURE SYSTEM. A pumping system that provide water, within pre-set flow and pressure ratings, automically on demand.

• Three basic Elements of the Pressure System 1. A pump (of any type or manufacturer) 2. A pressure sensing electric switch- opens and closes the electrical

contacts causing the pump to stop and start. 3. Pressure vessel which contains an elastic medium, usually air.

ILLUSTRATION

WELL PUMP SELECTION

PUMP CAPACITY

DEPTH OF WELL

0 to 8.00m 8.00 to 18.00m 18.00 to 27.00m

27.00 to 46.00m

46.00 and over

1,136 to 2,271 LPH (300-600 GPH)

�Submersible pump �Jet pump �Piston Pump

�Submersible pump �Jet pump �Deep well �Reciprocating Pump

�Submersible pump �Jet pump �Deep well �Reciprocating Pump

�Submersible pump �Jet pump �Deep well �Reciprocating Pump

�Submersible pump �Jet pump �Deep well �Reciprocating Pump

2,271 to 4,542 LPH (600-1200 GPH)

�Submersible Pump �Jet Pump �Plunger Pump

�Submersible pump �Jet pump

�Submersible pump �Jet pump

�Submersible pump �Jet pump

�Submersible pump

Over 4,542 LPH (1200 GPH)

�Submersible Pump �Jet Pump �Plunger Pump

�Submersible pump �Jet pump

�Submersible pump �Jet pump

�Submersible pump

�Submersible pump

THE PUMPING OF WATER In the pumping of water, the following are to be considered:

1. Mass of water to be lifted 2. The height through which it must be lifted or forced. 3. The distance it must travel in moving from one place to another. 4. The ways in which in water may be affected by friction.

Pressure- is defined as force per unit area, the area being measured at right angles to directon of the force. The unit of pressure N/m2 is called Pascal (Pa). Kilo Pascal (kPa) and Mega Pascal (MPa) are commonly used. Head- is the height or vertical distance from the point of measurement to the free level of water in the system.

a. Positive Head- occurs when the free water level is higher than the point of measurement.

b. Negative Head- occurs where the free water level is lower than the point of measurement. It is also known as suction, partial vacuum or negative pressure.

*Water with head of 1.00m and a base of 1m2 will exert a pressure of 9810 N/m2, or 9810 Pa, that is 9.81 kPa.

• Classification of Heads There are different kinds of head according to their effect on pumping operations.

1. Static Discharge Head or Gravity Head- results from the vertical height of a

column of water. It is the weight of water exerted as a result of the force of gravity. In pumping operatons, it is the vertical distance (in meters) from the center line of the pump to the point of free discharge.

2. Pressure head- the vertical height to to which a given pressure will force water to a certain level

3. Suction Lift- the term used when the source of supply is below the center line of the pump.

4. Static Suction Lift- the vertical distance (in meters) from the liquid level to the center line of the pump.

5. Total Suction Lift- the static suction lift plus friction head in the entire suction pipe and fittings.

6. Suction head- the term used when the source of supply is above the center lne of the pump. Also known as flooded suction.

7. Static Suction Head- the vertical distance (in meters) from the center line of the pump to the level of the liquid being pumped.

8. Total Suction Head- the static suction head minus the friction head in the entire suction pipe and fittings.

9. Total discharge Head- the static delivery head plus the friction head plus the friction head in all of the delivery pipe and fittings.

10. Velocity Head- the head required to accelerate the water in the delivery pipe. It should be included in the total pump head but it so nominal that it is usually ignored.

11. Total Pump Head- the total suction lift plus the total delivery plus the velocity head.

CHAPTER 11: DOMESTIC HOT WATER SUPPLY SYSTEM

DOMESTIC HOT WATER SUPPLY The supply of hot water of domestic use is based on the need for personal hygiene and washing in order to remain healthy and safe.

1. Personal hygiene- through science, people became aware that dirt harbors disease, to keep away from this condition people attend to constantly maintain their bodies clean. To achieve this, a regular supply of hot water is required to break down and dissolve oil and dirt. Soap lathers much better in hot water than cold. Hot water is friendlier to our skin temperature since we are warm blooded

animals. Hot water also helps to open skin pores, letting the soap get down into the tissue to lift out the oil and dirt.

2. Washing- certain substances, such as fatty foods on a plate, require a temperature of 60 degrees centigrade to lift them.

There are several methods of heating water , but the availability of fuel and the cost involved in operating and maintaining the system are main concerns in choosing the suitable type. The types of fuel currently available are:

1. Electricity 5. steam 2. Solid fuel- coal 6. Oil 3. Gas 7. Heat pumps 4. Solar

HEAT-UP TIME In order to achieve the greatest convenience and the best running cost, knowledge of the heat-up time for water heaters is important. Capacities of water heaters vary according to requirements, storage size and heat input. This is the reason why most heaters have to be turned- on before use as they need time to heat up. To be able to calculate the heat- up time we need to understand a few facts about heating water.

1. Specific heat- is the specific amount of heat for a specific temperature rise. It takes 4.187 kJ (kilo Joules) of energy to raise 1 kilogram of water through 1 degree centigrade.

2. For the purpose of calculations, 1 liter of water has a mass of 1 kilogram. 3. Temperature Rise (TR)- is the difference between the cold water temperature

and the final required temperature. This is expressed in the formula: TR= (t2-t1) 4. Often the water heater is electrical equipment that is related in kilowatts (kW), it

is necessary to convert kJ to kW. The conversion is kW= 3600 kJ.

Knowing the quantity of water to be heated, the temperature rise and the specific heat of water, we can calculate the amount of heat required, and because electrical appliances have the input based on an hourly rate, these figures can be reversed to find the time it would take to heat up. SAMPLE PROBLEM Calculate the amount of electrical energy and the time required to heat 13 liters of water from 10oC to 60oC at 100% efficiency. Solution

1. Solving for Temperature Rise: TR=60oC - 10oC= 50oC 2. Solving for Energy Required

Energy Required = liters x temperature x specific heat = 13 liters x 50oC x 4.187 kJ/ liter oC = 13 liters x 50oC x 4.187 kJ Liter degree centigrade = 2,721.55 kJ

3. Convert kJ to kW kW= 2721.55 kJ 3600 kJ/ kW

4. Solving for Time Required

T= 2721.55 kJ 3600 kJ/ kWh x 0.76 kW

Convert hours to minutes: T= 0.99 hours x 60 minutes / hour = 59.4 minutes The above time of 59.4 minutes is quite impractical for a waiting time before hot water is available. To shorten the waiting time, the input should be increased. ADDENDUM OF SAMPLE PROBLEM *If we double the input from 0.76 kW to 1.52kW, calculate the time it will take to reach the required temperature. Solution. Use the same figures but this time double the input. T= 13 liters x 50 oC x 4.187 k 3600kJ/ kWh x 1.52kW = 2721.55 kJ = 0.497 hours 5472 kJ/ h

Convert hours to minutes T= 0.497h x 60 min/ h Time= 29.82 minutes

TYPES OF HOT WATER SYSTEM AVAILABLE The above stated types of fuel can be used to heat the water in the following systems:

1. Localized water heating (single appliances) a. High Pressure b. Low Pressure

2. Centralized hot water system a. High Pressure b. Low Pressure

3. Storage water heaters a. High Pressure b. Low Pressure

4. Instantaneous water heaters a. High Pressure b. Low Pressure

STORAGE WATER HEATER- OPEN OUTLET SINGLE POINT, ABOVE SINK All heaters of this type are designed to serve one fixture at a time. Although, it is possible to install the heater between two adjacent fixtures so the swivel spout can be turned to supply both. They are available from 7 to 34 liters storage and normally have a 2000 watt element fitted. This means that there is heat-up time of 12 minutes to 1 hour. STORAGE WATER HEATER- OPEN OULET SINGLE POINT, UNDER SINK The under sink water heater works on the principle of displacement, hot water only flowing when cold water enters the cylinder and pushes the hot out. To prevent undue pressure from the cold water inlet, a restrictor is fitted to the inlet connection. Provision must be made for expansion and this is done by leaving the hot water outlet open and

discharging it over the sink. The cold water faucet controls the flow of hot water and the hot outlet pipe allows for expansion. Under sink water heaters are not suitable for use with dish washers, unless installed as low-pressure water heaters.

INSTANTANEOUS HEATERS Instantaneous heaters instantly heat cold water as it passes through the heater. These heaters are compact since storage is not required. They are popularly used at showers and lavatories and due to this condition; there is a shower model and lavatory model.

1. Shower model- has rated power consumption of 6000 watts (6kW) - provides a continuous supply of hot water at a maximum rate of 3 liters per minute at a showering temperature of 40 degrees centigrade.

2. Lavatory model- has a rated power consumption of 3000 watts (3kW) -provides a continuous supply of warm water for hand washing at the rate of approximately 1.4 liters per minute.

3. Multi-point model- serves several fixtures such as a range of lavatories, sink or . shower.

OPERATION OF INSTANTANEOUS HEATER

1. When the cold water control valve is turned on, water flows and exerts pressure on a pressure switch which in turn completes the electrical circuit so that the element can now heat the water as it passes through. The pressure switch is the safeguard that the heating element is only on when water is flowing.

2. A preset thermal cut-out switch is also incorporated as a safety measure against overheating the water.

3. The heating element is thermostatically controlled using a rod thermostat or invar steel which expands very little. This is fixed inside a tube of brass which expands very little. This is fixed inside a tube of brass which expands approximately 18 times as much as the invar steel. When the brass tube, which is in contact with the water, expands, it draws out the invar rod with it and breaks the electrical contact.

4. A magnet ensures a clean snap action, as the magnet will hold the control switch until the last minute, so preventing excessive arcing and rapid deterioration of the contact points.

CENTRALIZED HOT WATER SUPPLY

� In centralized systems, water is heated and stored centrally and distributed to the hot water faucets via the hot water piping. In the average home, an electric heating element is directly immersed into the water to be heated. But, for commercial and larger projects an independent boiler or furnace is used to heat the water remotely. The hot water is stored in a range boiler or storage tank that is located as near the boiler as possible to keep heat losses at a minimum.

� To provide an adequate supply of hot water for the average family, a 180 liter storage cylinder is recommended and is designed to provide the central bulk of the hot water requirements. The aforementioned value should be increased if there is an abnormally high usage of hot water or be supplemented with secondary forms of heating water.

1. The hot water storage vessel holds sufficient water to meet a large draw-off at peak times.

2. It may be possible to use cheaper, lower grade fuel oil, coal, natural gas or other solid fuel.

3. The boiler can be housed in its own room, keeping noise and dust out of the main building.

4. One boiler plant reduces maintenance. PARTS OF CENTRALIZED HOT WATER SUPPLY

1. Heating element/ boiler 3. Range boiler/ hot water storage tank 2. Thermostat 4. Hot water pipes

• Heating element- the size of the heating element has a direct bearing on the heating up time, which is also related to the size of the storage cylinder. A general guide for adequate supply is: 135 liters � 1500 watts

180 liters � 2000 watts

Both the 180 liter with a 2000 watt element and the 135 liter with a 1500 watt element will reach a temperature of 60 degrees centigrade in 5 hours and 15 minutes, based on cold water entering the cylinder at 10 degrees centigrade. Caution: It is not uncommon for higher wattage elements to be installed, up to 3000 watts in a 135 liter cylinder, but when this is done in an old installation, the wiring should be checked to avoid electrical overloading that may result to fire.

• Thermostat- is the key to a satisfactory and economical water heater, automatically switching off the power when the preset temperature is reached and switching on again when hot water is drawn off, or the temperature drops through heat loss. Recommended thermostat settings for average family requirement are 65 to 0 degrees centigrade. Where there are smaller demands, 60 degrees centigrade is more economical temperature. Some savings can be made by lowering the temperature setting during summer.

• Range boiler/ hot water storage tank- the hot water tank serves the domestic hot water system in a storage capacity. There are two types of tanks used for the storage of hot water:

1. Range boiler- the small cylindrical hot water tank that varies in size from

300 mm to 600 mm in diameter and is not more than 1800 mm long. The range boiler is made of galvanized steel sheet of standard and extra heavy gauge. It can be used in either horizontal or vertical position.

2. Storage tank- the large cylindrical hot water tank with a range of diameter at 600mm to 1350 mm and not more than 4500 mm long.

The proper size of the hot water storage tank depends on the following:

1. The design of the building 2. The number of occupants and 3. The heating capacity of the supply device

• Hot water pipes- should be as short as possible in order to avoid the use of “dead legs”. A “dead leg” is a long pipe run whereby it takes a long time to push out the cold water for the sake of a small amount of hot water. The smallest size of piping that will provide a satisfactory flow should be used. Short, small sized pipes are less expensive and they waste less heat and less water.

HOT WATER DISTRIBUTION SYSTEM

The storage tank and heating device of a hot water distribution system are so assembled as to create a circulation of water within them. The movement of the water is the result of molecular activity. The application of heat to a body of water caused it to expand and become less dense, which give it a natural tendency to rise. The inequality of weights between the hot and the cold water contained in the tank results a circulation of the liquid. The operation and efficiency of the hot water distribution system is dependent upon the following:

1. Type of heating system used a. Direct system b. Indirect system

2. Type of tank connection used

a. Vertical position b. Horizontal position c. Pipes, valves and fittings

3. Types of installation used

a. Upfeed and Gravity return b. Overhead feed and gravity return c. Pump circuit system

DIRECT HEATING SYSTEM In this system the water that is being heated by the boiler is actually used out of the hot water faucets. Direct water heaters are classified into four categories:

1. Range boilers a. Range boiler and furnace coil b. Range boiler and heater

2. Gas water heaters a. Side-arm gas heater b. Gas water heater

3. Oil-Fired water heater 4. Electric water heater

Each type should have a temperature and pressure relief valve and sediment drain at the lowest part of the tank. Relief valves are set to allow water to blow into a drain line when the temperature exceeds 100 degrees centigrade or when the pressure exceeds 860 kPa.

• Range Boiler and furnace coil- the range boiler is usually mounted upright on a stand. A drain is placed at the bottom to remove sediment; a temperature and

pressure relief valve is placed at the top for safety. The furnace coil is located in the furnace box.

• Range boiler and Heater- the range boiler is usually installed horizontally on a stand. The heater maybe fired by coal, gas or oil.

• Side-Arm Gas Heater- is used mostly during summer months in temperate countries to support furnace oil heaters.

• Gas water heater- a galvanized iron, copper, or porcelain- lined steel tank enclosed in an insulating jacket. A gas (LPG) burner provides the heat. The thermostat controls the temperature of the water in the insulated tank. Its operation is automatic and will keep water at any temperature from 45 to 75 degree centigrade, according to the setting of the thermostat. Gas water heaters provide an efficient and inexpensive way to supply hot water at all times.

• Oil-Fired water heaters- are similar to the gas water heater, except that a vaporizing or pressure oil burner supplies the heat.

• Electric Water Heater- normally has two immersion type heating elements. The upper heater usually has higher wattage than the lower. Thermostats control these elements to ensure that the operation is automatic. The heater does not need a flue or smoke stack since there are no burning products. The electric water heater may be located in a closet.

INDIRECT HEATING SYSTEM In this system the water that is heated by the boiler is never used out of the hot water faucets, but circulates through a heat exchanger. This takes the form of a coil pipe within the hot water storage tank. The heated water circulates through the system and in turn heats the water held within the storage tank, then results to the boiler to be reheated. The advantages of this system are:

1. Since the water in the boiler does not mix with the water in the storage tank, the risk of rusty water being drawn off through the faucets is eliminated.

2. It keeps the carbonate deposits to a minimum level because once the temporary hardness of the water has been released it will not recur as the same water is reheated over and over again.

3. It can use steam as the heating medium instead of water. There are 3 types of indirect heating system currently used in buildings, these are:

1. Primatic Cylinder 2. Calorifiers 3. Annular Cylinder

1. Primatic cylinder- is a single feed cylinder with a patented internal heat

exchanger. It is designed with two air locks, which prevent the mixing of the heated water with the useable water.

2. Calorifiers- is a continuous coil of pipe within a vertical cylinder. In hospitals and factories where steam is already being generated for other uses, it can be used to heat the water by the indirect method through the calorifier. The steam enters the coil through the top connection. The strainer removes any solid matter suspended in the controlled. The thermostat prevents overheating or boiling of the stored water. A steam trap, fitted near the outlet of the coil, prevents the steam from leaving the coil until it condenses.

3. Annulars cylinder- is a horizontal calorifier that works in a similar way to that described above. This best suited for areas with limited headroom.

NOTE: Where water is being used for heating , the “rule of thumb” to determine the heating surface is approximately 1000 cubic centimeter of heating surface per 10 liters of water in the storage tank. For 180 liters of stored water, this works out to approximately 21 meters of a 15 mm diameter pipe or 16 meters of a 20mm diameter pipe.

Indirect water heating with an annular cylinder

STORAGE TANK CONNECTION

It is advisable to seat the tank in a vertical position on small installations and in a horizontal position on the larger installations. In both the vertical and horizontal position, the tank must be set above the heater to allow the heated water to rise and permit a more rapid circulation. Other necessary connections to the tank are:

a. Cold water supply- delivered into the tank via a boiler tube that extends to within 150mm of the tank bottom. The purpose for this is to avoid the possibility of cooling the hot water which accumulates at the top of the tank. This cold water line must have a small hole within 150mm from the top of the tank. This hole serves as a vacuum breaker and prevents siphonage. The supply line into the tank must be equipped with a control valve located as close to the hot water tank as possible.

b. Flow connection- is connected to an opening on the tank somewhere above its center point. This line is called the flow connection because the heated water flows from the heater in the tank.

c. Return connection- is connected to a tapping on the bottom of the tank. This line is called the return connection because it returns the colder water from the bottom of the tank of the heater.

d. Drain valve- is located at the lowest point of the storage tank. e. Hot water distribution pipe- is connected to a tapping on the top of the tank at

the point near the flow inlet. f. Blow-off valve- is installed to the storage tank to control the temperature and

pressure and to prevent serious difficulties should the tank become overheated. HOT WATER DISTRIBUTION: Types of installations The installation for hot water distribution consists of the piping work that conveys the heated water from the storage tank to the plumbing fixtures.

• Upfeed and Gravity Return system - Commonly used in residential installations - The purpose of this system is to permit circulation of hot water within the

piping arrangement - The circulating return is economical since it eliminates water waste. - The principle on which this system functions is provided in the unequal

weights of 2 columns of heated water of uniform height. The inequality of weight is the result of a variation in temperature in the 2 columns.

FEATURES OF THE UPFEED AND GRAVITY RETURN SYSTEM:

a. The distribution main is connected to a tapping on the top of the storage tank close to the flow from the heater. This pipe is usually suspended from the basement ceiling.

b. Hot water rises are generally connected to the distribution main by means of 45 degree connection.

However, this practice may vary according to the length of the risers, in order to avoid one riser circulating faster and more thoroughly than the others. For example, should an installation consists of 3 risers of varying heights, the longest can be connected to the main horizontally; the shorter riser by a vertical connection; and the third riser maybe connected with a 45 degree fitting.

c. The flow riser is passed as near the fixtures as possible. Swing joints are provided in the supports of risers to allow for expansion and prevent breakage of the pipes. The flow riser is equipped with a control valve and a drip at its base.

d. The circulating return is connected to a tee that is installed in the riser below the highest fixture to overcome air lock. The return is usually one size smaller that the flow riser. It is connected to a return main often suspended from the basement ceiling. The return riser is also equipped with a drip and a control valve at its base.

e. The circulating main is usually suspended from the basement ceiling and installed with a slope to a Y fitting installed in the return connection between the storage tank and the heating unit. A valve must be placed at this connection.

f. All valves used in the system should be of the gate valve type in order to be assured of a full way water flow and to overcome trapped water lines- a fault which occurs in the use of disc or globe valves.

g. The largest diameter of the pipe is at the bottom of the riser, the size diminishing as it passes through the upper floor s of the building.

OVERHEAD FEED AND GRAVITY RETURN SYSTEM - The most efficient method of delivering hot water to fixtures. - It is generally used in multi-storey buildings. - It is dependent on the natural laws governing expansion and gravity - Its advantage is that it allows continuous circulation even if there is a

mechanical defect in the system. - The operating principle of the overhead system is based on the fact that in a

closed system of piping, water rises when heated. After it has reached the high point of the system, natural forces of gravity return it to the storage unit.

FEATURES OF THE OVERHEAD FEED AND GRAVITY RETURN SYSTEM

a. The storage tank should be located at the lowest point of the distribution piping. b. Overhead feed riser is connected to a tapping at the top of the storage tank close

to the flow connection of the heater. This riser must be extended as direct and free from offsets as possible to the work space or the ceiling above the top floor of the building. This riser must not have connections from fixtures.

c. Distribution main is connected to the top of the riser, and is suspended from the ceiling or the building framework by means of metal hangers. The main must be pitched away from the riser so that the water will flow to the last drop. The main shoulder be located so as to make the horizontal runs of the riser as short ans as equal in length as possible.

d. The horizontal riser branch is connected into the main by means of inverted 45 degree fitting and is pitched to the drop or vertical riser proper. The horizontal riser branch must be equipped with a valve installed as close as may be practical.

e. The largest pipe diameter is at the top of the riser, the size diminishing as it passes through the lower floors.

f. The circulating return main is a line suspended from the basement or lowest floor. It is pitched and connected to a Y located at the return piping between the heater and the storage tank.

g. The return risers are connected to the circulating return main. h. The system is equipped with a relief vent that eliminates the accumulation of air

(air bound) at the top most point of the distributing piping. Air bound is a condition in the pipe works that retards or prevents the circulation of hot water. There are two methods to provide a relief vent in the system; 1 connects an uncirculated riser to the highest point of the overhead distribution main. It is possible to relieve the air lock from time to time by opening the fixture/ faucet that the riser serves. 2, by installing an air relief valve, which opens when the air accumulates and automatically closes when the air is released. The relief valve is equipped with a drain pipe that allows water to drip to an open fixture.

PUMP CIRCUIT SYSTEM -The circulation of hot water to the plumbing fixture by means of mechanical device, usually a centrifugal pump. The rotary motion of the impeller of the centrifugal pump creates an even movement of hot water flow in the pipes which makes this pump practical to use. - this is used in buildings where it is impossible to produce a circulation of hot water. FEATURES OF THE PUMP CIRCUIT SYTEM

a. The pump is installed on the circulating return main as close to the heater as possible.

b. The circulating return is connected to the inlet side of the pump and the outlet side of the pump is connected into the return of the heater.

c. It is advisable to equip the pump with a by-pass, which is done by inserting tees of the same diameter as the circulating return ahead of the valves. The tees are connected and the line is equipped with a gate valve. Should the pump get out of order, the control valves may be closed and the hot water will circulate around the pump into the return pipe of the heater. This practice serves as a temporary means of water circulation. When the by-pass is not in use, the valve with which it is equipped must be closed. The valves on either side of the pump must be open at all times when the pump is in operation.