Waste water in USJP and water treatment Methods
A presentation Done by the 1st Year Students (Group 5) of the Department of Forestry and Environmental Sciences, University of Sri Jayewardenepura for the Environmental Chemistry Assignment..
3. Introduction Wastewater is any water that has been adversely affected in quality by anthropogenic influence. It comprises liquid waste discharged by domestic residences, commercial properties, industry, and/or agriculture and can encompass a wide range of potential contaminants and concentrations. In the most common usage, it refers to the municipal wastewater that contains a broad spectrum of contaminants resulting from the mixing of wastewaters from different sources. Since our project was about on waste water ,we concern about the waste water coming from university premises. we have taken waste water samples of , boys and girls hostels and did some experiments inorder to take an idea about the influence on surrounding by the releasing waste water. in addition to that we concern about the places where waste water ultimately releasing from canteens and laboratories of the university premises.
4. Waste Water in Canteens When consider about the Wastewater in canteens of University of Sri Jayewardenepura, We have checked what is happening for the waste water coming from those places. For this we consider about all the canteens in the University including those inside the hostels. All the waste water coming from the canteens are directly connected to the septic tanks which were placed near each canteen. These waste water will be will be removed when those are filled out.
5. Waste Water From the Laboratories of University When we consider about the laboratories of University mainly following labs in the Faculty of Applied Sciences can be taken, Chemistry Laboratories Organic Inorganic Physical Forestry and Environmental Science Laboratories Food Science and Technology Laboratory Aquatic Science Laboratories Botany Laboratories Zoology Laboratories
8. Physical Chemistry Laboratories Waste water is sending to the three septic tanks because of the chemicals use in those laboratories are different from each other
22. Waste water from Hostels There are more than 750 boys and more than 1200 girls inside the hostels. Here we consider about the waste water coming from the bathrooms of those. waste water of the hostels directly go to some cannels without any pre-treatment. Rahula Girls Hostel – Delkanda Cannel Soratha and Dharmapala Girls Hostels – Raththanapithiya Cannel Boys and Clergy Hostels - Raththanapithiya Cannel
28. Discussion The increase of pH on sample than the tap water since the sample contain detergents, soaps in high concentration. Due to the high concentration of soap and detergents in the sample the ion concentration is also increase therefore the conductivity of the sample was also increased than the tap water. Since the sample water is mixing thoroughly (when it’s flow) the DO value was increased then the tap water.
31. Septic tank…. Kind of Treatment sedimentation, sludge stabilization Kind of wastewater Treated wastewater with main pollution by settleable solids, esp. domestic Advantages simple, durable, little space because of underground construction Disadvantages low treatment efficiency, effluent not odourless
33. Imhoff tank Kind of Treatmentsedimentation, sludge stabilization Kind of wastewater Treated wastewater with main pollution by settleable solids, esp. domestic Advantages durable, little space because of underground construction, odourless effluent Disadvantages less simple than septic tank, needs very regular desludging
35. Anaerobic filter Kind of Treatment anaerobic degradation of suspended and dissolved solids Kind of wastewater Treated pre-settled domestic and industrial wastewater of narrow COD/BOD ratio Advantages simple and fairly durable if well constructed and wastewater has been properly pre-treated, high treatment efficiency, little permanent space required because of underground Construction Disadvantages costly in construction because of special filter material, blockage of filter possible, effluent smells slightly despite high treatment efficiency
37. Baffled septic tank Kind of Treatmentanaerobic degradation of suspended and dissolved solids Kind of wastewater Treated pre-settled domestic and industrial wastewater of narrow COD/BOD ratio, suitable for strong industrial wastewater Advantages simple and durable, high treatment efficiency, little permanent space required because of underground construction, hardly any blockage, relatively cheap compared to anaerobic filter Disadvantages requires larger space for construction, less efficient with weak wastewater, longer start-up phase than anaerobic filter
39. Constructed wetlands (Horizontal gravel filter) Kind of Treatment aerobicfacultativeanaerobic degradation of dissolved and fines suspended solids, pathogen removal Kind of wastewater Treated domestic and weakly polluted industrial wastewater after removal of settleable and most suspended solids by pretreatment Advantages high treatment efficiency if properly constructed, pleasant landscaping possible, no wastewater above ground, cheap in construction if filter material is locally available, no odour nuisance Disadvantages high permanent space requirement, costly if right quality of gravel is not available, great knowledge and care required during construction, intensive maintenance and supervision during first years
41. Anaerobic pond Kind of Treatment sedimentation, anaerobic degradation and sludge stabilization Kind of wastewater Treated heavily and medium polluted industrial Wastewater Advantages simple in construction, flexible with respect to degree of treatment, low maintenance requirements Disadvantages wastewater pond occupies open land, there is always some odour, at times strong, mosquitoes are difficult to control
43. Aerobic pond Kind of Treatment aerobic degradation, pathogen removal Kind of wastewater Treated weakly polluted, mostly pre-treated wastewater from domestic and industrial sources Advantages simple in construction, reliable in performance if properly dimensioned, high pathogen removal rate, can be integrated well into natural environment, fish farming possible if large in size and loading is low Disadvantages large permanent space requirement, mosquitoes and odour can become a nuisance if undersized; algae can raise effluent BOD
44. Thank You! Department of Forestry and Environmental Science, University of Sri Jayewardenepura, Gangodawila, Nugegoda, Sri Lanka.