Wastewater Treatment SYSTEMS By: Ahmed alhamadat

What is (in) Wastewater?

Pharmaceutically active compounds (PhACs) Water Quality Concerns Contaminants 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

- Environmental Problem - Finite Resources - Water Shortage Wastewater New Water Resource “ Reuse” WW Treatment Energy Technology Experience

Treatment Technologies Conventional Natural (CWs & MAR) Low Energy No Chemicals Robust Energy Chemicals Water with High 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

Wastewater production, treatment and reuse in Saudi Arabia, 2009 14% reused only 26% collected 80% treated (Arani Kajenthira et al, 2012)

Potential energy savings from increasing the use of treated wastewater rather than desalination in the municipal sector

How do we clean our wastewater? Trace chemicals, VOCs CO2 CH4 H2S Energy: Pumping Mixing Aeration Disinfection Heat for digester Chem transportation Chemicals: Flocculation Precipitation Labor: O&M Clean water Bioproducts Biosolids, Nutrients, biopolymers Energy? Unrecoverable waste residuals 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 main problems that have to be dealt with are: 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! Graphics: Jeremy Guest http://www.sustainlane.com/reviews/getting-the-most-from-human-waste/ICF8A2T14UAQ9HTV27Q8VLQXRTOI

http://www. myfoxtampabay http://www.myfoxtampabay.com/story/18612577/could-a-new-energy-source-start-right-here

Thank You and 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

Costs 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