Slaughterhouse wastewater treatment by trickling filter and activated sludge process | |
| Author | Rajbhandari, Annu |
| Call Number | AIT Thesis no. EV-91-15 |
| Subject(s) | Sewage--Purification--Filtration Sewage--Purification--Activated sludge process Factory and trade waste |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | The Pilot Scale Trickling Filter and Laboratory Activated Sludge Process were operated with the wastewater from a laughter house in Bangkok, Thailand. The Trickling Filter was fed with effluent from the anaerobic reactor and dissolved flotation unit. The total COD removal in the first case was 41 and 35 % for loading rate of 0.87 kg COD/(m3.d) and 0.4 kg COD/(m3.d) respectively. With the influent from dissolved flotation unit with 100 % recycle the total COD and BOD removal was 45 and 56 respectively for loading rate of 1.6 kg COO/(m3.d). Activated Sludge Process was studied for two different system; single stage and two stage. For two stage process, two units were operated at two different loading rate of 3.7 and 6.5 kg COD/(m3.d). As the unit was overloaded the effluent quality decreased when high concentrated water entered inside the reactor for the first loading rate. Nitrification occurred in the second unit of the first stage when the MLSS was 3300 mg/l in the first unit with loading rate 3.7 kg COD/(m3.d). For the second loading rate there were fluctuations in MLSS and COD effluent. Computer controlled feeding was done for activated sludge process with loading rates 0.8, 2.1, 4.3 and 8.5 kg COD/(m3.d) respectively. Feeding was done for 2, 5, 10, 20 minutes per hour simultaneously and stopped for 23 minutes and restarted again. The units with COD loading rates 0.8 and 2.1 kg COD/(m3.d) gave COD removal efficiency of 84 and 89 % respectively. Ammonia reduced to 0 mg/l in the unit with loading rate 2.1 kg COD/(m3.d) when the MLSS was between 1940-2355 mg/l. The trickling filter as a single unit was inadequate to meet the required effluent standards. The activated sludge process with a loading rate 2.1 kg COD/(m.d) was proposed as an alternative treatment system for treating slaughterhouse wastewater of the factory. Equalization tank with Activated Sludge process was recommended as there was a high variation in COD of the slaughterhouse wastewater. The activated sludge process gave an effluent filtered COD of 47 mg/l for a loading rate 2.1 kg COD/(m3.d) which is less than the effluent COD (78 mg/l) from the existing full scale ponds system. The total BOD with the same loading rate was 20 mg/l for the activated sludge process which met the BOD effluent standard of Thailand which is between 20- 60 mg/l. |
| Year | 1991 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Environmental Engineering and Management (EV) |
| Chairperson(s) | Verink, Johan |
| Examination Committee(s) | Harada, Hideki ;Kiran Bhattarai |
| Scholarship Donor(s) | Government of Germany (DAAD); |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1991 |