Vienna 2- 4 July 2007

Expert Group meeting On “Designing Mechanisms to Facilitate the Removal of Barriers to CFC-Chiller Replacements”

Vienna 2 -4 July 2007

Absorption Technology

Case Studies in Egypt

Dr. Alaa Olama

Vice Chairman, GasCool

Absorption Technology / Case Studies in Egypt

Contents:

1.0- Introduction

2.0- Absorption Technology

3.0- Advantages of Absorption Vs Mechanical Vapour Compression

4.0- District Cooling/Heating

5.0- Advantages of District Cooling/Heating

6.0- District Cooling/Heating at Smart Village (Cairo-Egypt)


7.0- District Cooling/Heating & Co-generation at the AUC

8.0- District Cooling/Heating at Petrosport

9.0- District Cooling/Heating at Echem

10.0- Absorption Vapour Compression benefits compared to M.V.C.

8-1 Environmental Impact

8-2 Economical Impact

8-3 Social Impact

11.0 -Conclusions and Recommendations

1- Introduction:

• The Egyptian Co. For Refrigeration by Natural Gas - GasCool has was established on September 29, 2004


1.1 -GasCool Shareholders:• Egyptian Natural Gas Holding Co. (EGAS) 20%• The Egyptian Natural Gas Co. (GASCO) 25%• PETROJET 20%• EGYPT GAS 20%• Dr. Alaa Olama (Vice Chairman) 10%• TOWN GAS 5%

1.2 -GasCool Capital:

• Paid Capital is LE 40 million ( $ 7.1 million). • Authorized Capital is LE 110 million ( $ 19.3 million).

Low Side

MECHANCIAL VAPOUR COMRESSIONHigh Side

Evaporator

CondenserPOWER

(kW)

Compressor

E.D.

CondenserHEAT (Q):Natural GasDiesel Steam Hot Water

High Side

Low Side

VAPOUR ABSORPTION MACHINEGenerator

AbsorberEvaporator

E.D.


2.0 Absorption Technology:

2.1-Comparison between Mechanical Vapour Compression Cycle and Absorption Vapour Cycle:

1. The heating causes the solution to release the absorbed refrigerant in the form of vapour. This vapour is cooled in a separate chamber to become liquid refrigerant.


2.0 .Absorption Technology (Cont.) 2.2 .Absorption Theory :

2. Boiling point of the water is a function of pressure. At atmospheric pressure water boils at 100 deg. C. When maintained at high vacuum, water will boil and subcool itself. The boiling point of the water at 6 mmHg (abs) is 3.7 deg. C.

3. Lithium Bromide (LiBr) has the property to absorb water due to its chemical affinity. At higher concentration and lower temperature LiBr absorbs water vapour (refrigerant vapour) very effectively.

4. As Lithium Bromide becomes dilute it loses its capacity to absorb water vapour. It thus needs to be re-concentrated using a heat source. Heat source may be Steam or Flue gases or even Hot water.


2.0 .Absorption Technology (Cont.) 2.3 .A Direct Fired Absorption Chiller:

3.0- Advantages/Disadvantages of Absorption Vs

Mechanical Vapour Compression:

3.1. Disadvantages:• Bulkier than comparable capacity Mechanical Vapour Compression system.

•Sluggish response to rapid variable loads when compared to Mechanical Vapour Compression system.

• Needs chimneys for flue gases that may be objectionable ecstatically.

•Fine leveling and a larger cooling system are a hindrance when water cooled.

•Crystallization is a concern that needs to be addressed with care.

•Must be water cooled at large capacities which may be prohibitive where water scares.


•Saves about 70-80% of the required electrical power needed for equivalent capacity mechanical compression systems.•Saves from 30% to 40% of operating expenses compared to mechanical compression systems in Egypt.•Mechanical wear is low.•Relatively low noise operation.•Low maintenance cost.•The Refrigerant (water) is environment friendly compared to refrigerant of the equivalent mechanical compression systems (CFC or HCFC).•Longer life expectancy , 20-22 years without major overhauls, compared to 15-18 years for equivalent mechanical compression systems after a minimum of one major overhaul.

3.0- Advantages/Disadvantages of Absorption Vs Mechanical Vapour Compression (Cont.):3.2. Advantages:


4.0 .District Cooling/Heating



4.0 .District Cooling/Heating (Cont.)

•The centralized production and distribution of

cooling/Heating energy.

•A Piping network is used for distribution.

•A central plant or more meets the cooling/heating energy

demand of dozens of buildings.

•The Centralized production of cooling energy is more

environmentally friendly.

•District Cooling/Heating is more cost-effective than

distributed individual building cooling.

• Centralization improves operational reliability.

•Individuals can be billed according to their usage through

energy meters.


5.0 .Advantages/Disadvantages of District Cooling/Heating

5.1 Disadvantage

-Can only be used effectively for large cooling/heating loads.

-Needs large initial budgets.

-The piping network cost constitute a large investment.

-Care should be given when calculating the piping network losses as those may be sizable.


5.0 .Advantages/Disadvantages of District Cooling/Heating (Cont.)

5.2 Advantages

- Total chillers installed capacity is lower than the algebraic sum of individual buildings capacities

which allow for less chillers installed in the

district (15 to 20%).– Highly efficient at large cooling/heating loads,

which reduces emissions harmful to the atmosphere. – Highly dependable specially at peak loads.– Allows for stand –by capacity at economic cost.– Decreases cost of O&M in individual buildings when

compared to central plant O&M cost.– Reduces initial cost for individual buildings.

6.0 .District Cooling/Heating at Smart

Village (Cairo-Egypt) :

Contract duration is 50 years; GasCool was awarded The First District cooling/heating Project in Egypt. The contract was signed on 16 May 2004. The LE 290 million (US $ 51 million) , BOO (Build, Own and Operate) project will be built in phases according to this IT companies conglomerates village needs.



Village (Cairo-Egypt) (Cont.) :The first phase of the project is now operational and consists mainly of:

The plant:The plant consists of eight modules of 1200 Ton Refrigeration (nominal capacity), N. gas fired absorption chiller units. The units provide both chilled water and hot water to the piping network.

Piping network:Piping network is a four pipes system connecting the plant to the buildings, with a total length about 42 KM with diameters ranging from 42" to 6."


Electrical sources:The project is supplied with the required electrical energy through 11KV/38OV transformers sub-station.

Control system:The plant is connected to a Building Management System for performance monitoring.The first stage of the project was inaugurated in April 2006, with a total refrigeration capacity of 8000 Tons.


Village (Cairo-Egypt) (Cont.) :


7.0. District Cooling/Heating & Co generation at the American University in Cairo:7.1- Definitions of the BOO project of the AUC

– Definitive agreement signed Feb. 9th ,2006.

– AUC pays for consumption through tariffs for: • Cooling / Heating per TR/hr.• Electricity per KWhr.• Domestic hot water per KW Thermal.

– Installed capacities:• 5 000 TR Cooling.• 6 900 KW Heating.• 7 000 000 TR.hr yearly cooling energy.• 1 600 X 3 KW N. Gas Electric Generating sets.


7.2- Description of the plant.

7.2.1 Cooling• 4 X 1 200 TR,nominal Absorption N. Gas fired chillers• 1 X 700 TR, nominal Absorption N. Gas fired chiller• 5 Induced draft cooling towers. • 6 CH.W. Primary pumps, C.S.• 6 C.W. Pumps, C.S.• 5 CH.W Secondary pumps, V.S.• Controls, electric works& ancillaries.

7.2.2 Heating• 2 X 3 500 Kw Hot water boiler• 3 Hot water pumps.• Controls,electric works& ancillaries.

7.0. District Cooling/Heating & Co generation at the American University in Cairo (Cont.):


• 7.2.3 Electricity and Cogeneration

3 X 1 600 Kw. Gas fired Gen. sets.

3 X 2 MVA Cast resin, dry type transformer.

2 X 2.5 MVA Cast resin, dry type transformer.

3 X 920 Kw Heat recovery boilers.

1 X 2 500 Kw Stand-by hot water boiler.

3 Hot water circulating pumps.

Controls, electric works &

ancillaries.



7.3- Description of the pumping system.



Primary-secondary-tertiary pumping.

8-0: Absorption Vapour Compression benefits compared to M.V.C.:

8.1.Enviromental Impact:• Mechanical chiller uses specific amount of CFC which will

be released to the atmosphere on average twice in the

life of the chiller (0.5 kg CFC for every TR).

• Absorption chiller uses environmentally friendly refrigerant (water) and environment friendly absorbent (LiBr).

• Uses 20 % of the electrical power to drive an Absorption chiller when compared to a CFC based chiller which means reducing global warming.

• Equipment overhead transition lines, step up, down transformer, electric distribution grid and electrical switching gear are reduced by 80% which means better economical performance.


• Indirect fired absorption chillers uses recovered heat from Gas turbine exhaust resulting the following :

1- Improve the thermal efficiency of the system.2- Reduce exhaust temperature to the atmosphere.

8.2.Economical Impact

• Higher initial cost that is recovered with lower operating cost.•Lower infrastructure cost for electrical power generation & distribution.


8-0: Absorption Vapour Compression benefits compared to M.V.C. (Cont.):

8.1.Enviromental Impact (Cont.):


8-0: Absorption Vapour Compression benefits compared to M.V.C. (Cont.):

8.3.Social Impact:

-Redirect valuable electrical energy to improve quality of life standards.

- Shave off peak electrical demands in summer helping reduce frequent power outage in a rural area.

- Redirect saved electrical power to socially vital functions.

Vienna 2- 4 July 2007

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Transcript of Vienna 2- 4 July 2007