Advanced oxidation combined with a membrane : bio-reactor for landfill leachate treatment | |
| Author | Sumanaweera, Sumitha |
| Call Number | AIT Thesis no.EV-04-21 |
| Subject(s) | Sanitary landfills--Leaching Leachate Bioreactor landfills Membrane reactors |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. EV-04-21 |
| Abstract | Treatment of landfill leachate is a challenge to the present day environmental scientist because direct impact of environmental protection costs is unaffordable to the developing countries. However intangible benefits of such treatment, creates a demand for better treatment techniques. Due to this environmental research is needed toward economic means of protecting the environment. The effort made in this research into the treatment of landfill leachate is a step towards this goal. This work is a study of a biological process combined with a physico chemical method to treat landfill leachate. Use of membrane technology and advanced oxidation by ozonation are being proven to improve the efficiency of treatment of leachate. This study focuses on comparing the efficiency of a Membrane bioreactor (MBR) in landfill leachate treatment at its standalone status supp01ied by ammonia stripping as a pretreatment with continuous recirculation of ozonated effluent into the MBR. Efficiency of the process in terms of COD and BOD5 are mainly studied. Molecular weight cutoff study (MWCO) is used to identify refractory and non refractory fractions of influent and effluent. The systems pretreatment process, ammonia stripping was found to be 59% efficient. Also about 25% BOD5 removal occurred during ammonia stripping reducing BOD5/COD from 0.42 to 0.37. MBR organic loading was in the range of 2 to 3.5 kg/m3/d. Food to microorganism ratio was in the range of 0.25 to 0.44 kg/kg.d of MLSS. MBR process was 71.5% efficient in COD removal and 93% efficient in BOD5 removal. Also it showed a TKN removal efficiency of 35%. This efficiency was achieved with an average MLVSS/MLSS ratio of0.55 in MBR. DSVI of MBR sludge was 22 mL/g on average indicating sludge was difficult to settle. Also the drop in protein to carbohydrate ratio characterizes MBR sludge as difficult to settle. Continuous recirculation of ozonated MBR effluent in 1: 1 ratio with ammonia stripped leachate improved efficiency of MBR in terms of COD from 31 % to 46%. Also TOC removal efficiency increased from 31 % to 37%. The BOD5 removal showed a drop from 93% to 83%. Therefore it can be concluded that recirculation of ozonated effluent causes improvement ofMBR efficiency in a low magnitude. |
| Year | 2004 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. EV-04-21 |
| 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) | Visvanathan, Chettiyappan; |
| Examination Committee(s) | Shim, Shang-Gyoo; Thammarat Koottatep; |
| Scholarship Donor(s) | JJ/WBGSP;Asian Institute of Technology |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2004 |