WASTEWATER TREATMENT SYSTEMS BY: AHMED ALHAMADAT.
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Transcript of WASTEWATER TREATMENT SYSTEMS BY: AHMED ALHAMADAT.
WASTEWATER TREATMENT SYSTEMSBY: AHMED ALHAMADAT
What is (in) Wastewater?
Water Quality ConcernsContaminants of Concern: Pathogens
– Bacteria, viruses, protozoa
Inorganic chemicals – Total dissolved solids
Unregulated and unidentified trace organic chemicals– Pharmaceuticals– Personal care products and
household chemicals– Endocrine disrupting chemicals– Emerging disinfection by-products
Pharmaceutically active compounds (PhACs)
Coliform count is usually 105 – 106 /mL in raw sewage
Wastewater Characteristics Wastewater refers to liquid discharged from residential,
business buildings and institutions.Industrial wastewater is discharged from manufacturing
plants. Municipal wastewater is the general term applied to the liquid
collected in sanitary sewers and treated in municipal plants Domestic sewage is composed of human body waste and
sludge which is the wastewater resulting from personal washing, laundry, and cleaning of kitchen utensils
• Raw wastewater chemical constitutes (mg/l): BOD COD TSS metals TN TP 100-500 300-800 100-350 <1 20-85 4-15
Water recycling is reusing treated wastewater for beneficial purposes such as agricultural and landscape irrigation, industrial processes, toilet flushing, and ground water recharge – USEPA Region 9 Water Program
Recycled or reclaimed water is water that is used more than one time before it passes back into the natural water cycle. – Water Reuse Association
•Wastewater
- Environmental Problem- Finite Resources- Water Shortage
New Water Resource
“ Reuse”
WW Treatment
Energy
Technology
Experience
Treatment Technologies
Conventional Natural (CWs & MAR)
Low Energy
No Chemicals
Robust
Energy
Chemicals
WaterwithHigh
Quality
Objectives of WWT
Reduce organic content (BOD & COD) and TSS
Removal/reduction of nutrients i.e., N,P
Removal/inactivation of pathogenic microbes
Typical Stages in a Conventional Wastewater Treatment Operation
(Arani Kajenthira et al, 2012)
Wastewater production, treatment and reuse in Saudi Arabia, 2009
14% reused only
26% collected
80% treated
Potential energy savings from increasing the use of treated wastewater rather than desalination in the municipal sector
How do we clean our wastewater?
Energy:PumpingMixingAerationDisinfectionHeat for digester Chem
transportation
Chemicals:FlocculationPrecipitationDisinfection
Labor:O&M
Clean water
BioproductsBiosolids, Nutrients,
biopolymers
Unrecoverable waste
residuals
Energy?
Trace chemicals,
VOCs
CO2CH4
H2S
A more sustainable approach
Problems associated with WW reuse The real cost of the projects are usually considerably
higher than that estimated previously. This is in large part a result of insufficient planning before design and construction of water reclamation projects
Presence of pathogens in water, chemical contaminants or heavy metals because of insufficient treatment
The positive effects of using wastewater irrigation
Economic feasible water resource
It conserves potable water
It reduces pollution of receiving water bodies e.g. rivers, canals and other surface water resources
It decreases the needs for chemical fertilizers
It increases crop yields
It provides a reliable water supply to farmers
The potential negative effects of wastewater irrigation
Health risks for irrigators and communities with prolonged contact with untreated wastewater and consumers of vegetables irrigated with wastewater
Contamination of groundwater (nitrates)
Build-up of chemical pollutants in the soil (heavy metals)
Creation of habitats for disease vectors
Excessive growth of algae and vegetation in canals carrying wastewater (eutrophication)
Challenges associated with WW reuse
1. Social acceptance (farmers, retailers and consumers): This is the most sensitive area of this topic. Farmers are not going to reuse water, if their product cannot be sold. Consumers will not buy products where reuse water was used unless it is proven to be safe
2. Social issues: play a significant role in water reuse initiatives and should be adequately addressed. With adequate political will accompanied by awareness programmes these cultural, religious and social objections can be overcome.
3. Water quality monitoring: TE should be tested on regular basis to guarantee the matching with standards
The non-regulated use of treated water in agriculture The non-existing reuse criteria related to hygiene, public
health and quality control The non-existing reuse criteria related to irrigation
techniques, degree of wastewater treatment, and choice of areas and types of crops to be irrigated
The lack of efficient control and monitoring of urban wastewater treatment plants
The lack of trained personnel both in the competent authorities and the treatment plants
The low level of awareness of the farmers and the public at large
Wastewater as a renewable resource
A paradigm shift is underway!
http://www.sustainlane.com/reviews/getting-the-most-from-human-waste/ICF8A2T14UAQ9HTV27Q8VLQXRTOI
Graphics: Jeremy Guest
http://www.myfoxtampabay.com/story/18612577/could-a-new-energy-source-start-right-here
Thank Youand Any
Question?
Costs
Wastewater reclamation system costs are a function of facility capacity, end-use option and treatment process configuration
Costs can be identified estimating:
- facility construction costs
- equipment purchases and
- operation and maintenance fees
Site development and electrical cost are assumed as 10 and 15 percent of the total facility costs respectively
Reclamation system’s annual cost is comprised of treatment and distribution facility personnel salaries, operating fees (recurring power and chemical cost) and maintenance cost (equipment repairs and replacements)
Personnel requirements are a function of facility size and complexity
Maintenance cost (spare parts, replacements) are estimated generally as a percentage of equipment first cost (e.g. 5 %)
For pipelines and storage tanks, maintenance costs are projected as two percent of capital costs
Costs