0.1. 1. 10. 100. 1000. 10000. 100000. Raw Sample (Nov). Inland Surface water. Public Sewerage System connected totreatment at second stage. Irrigated Land.
A Comparative Study on Biological and Physicochemical Treatment Process of Leachates at Matuail Landfill Md. Delwar Hossain, Misbah-ul-Aziz Mostazi, Mohiuddin Imran, Md. Imran Hossain and Arif Hoosain Department of Civil Engineering, Bangladesh University of Engineering and Technology ,Dhaka ,Bangladesh
Background
Result Analysis (Seasonal Variation for Raw Sample)
Treatment of landfill leachate has become an issue of great concern for all the developing countries as the cost related to this is unaffordable for them.
100000 10000
t
1000
Research work is being done to find an economic means of protecting the environment from leachate pollution.
100 10
Matuail Landfill leachate was being analyzed.
1 0.1
Objective
0.01
• Analysis of seasonal variation of pollutant of leachate from Matuail Landfill and assessment of existing biological leachate treatment process. • Physio chemical treatment process as an alternative of Matuail Landfill Leachate Treatment, which includes:
0.001
Raw Sample (Nov)
Inland Surface water
Public Sewerage System connected totreatment at second stage
Irrigated Land
Fig: Comparison between Raw sample from November, 2014 and Discharge Standards Set by Department of Environment (DoE), Bangladesh on ECR, 97(Unit: mg/L)
Leachate treatment by air stripping Leachate treatment with by coagulation Leachate treatment by Granular Activated Carbon adsorption • Comparison between the biological and standard set of LPI and recommended the best alternative for the treatment of Matuail landfill project as well as other landfills in Dhaka city.
Result Analysis (Comparison Among Treated & Untreated Sample) 40 35 30 25
Current Condition of Matuail Landfill
20 15 10 5 0 LPIor
LPIin
LPIhm
Overall LPI
Raw sample form September,2014
Standard (Indland)
Standard (Second Stage)
Standard (Irrigated)
24 hour air stripped supernatant
Alum coagulated supernatant (2000)
GAC (2000)
Biologically Treated
Fig: Comparison between Raw sample from November, 2014 and Discharge Standards Set by Department of Environment (DoE), Bangladesh on ECR, 97(Unit: mg/L)
Findings
Assessment of Existing Leachate Treatment Process (Biologically Treated Effluent)
Seasonal variation for leachate generation in Matuail landfill was found greater for the month of November rather than that observed from March or September.
The LPI of the raw leachate collected in September is 12.94 The Three discharge standards, Inland water discharge standard, Public sewerage system connected to treatment at second stage Discharge standard ,Irrigated land discharge have LPI of 6.11,9.08, 6.29.The raw leachate does not satisfy any of standard and it to be treated. The LPI of Biologically treated effluent from Matuail Leachate Treatment Plant is 6.55 only Which only satisfies public Sewerage system connected to the treatment at second stage discharge standard .Alternative treatment is required.
Biological treatment satisfies the Second Stage Discharge Standards Set by Department of Environment on ECR, 97, it does not satisfy the other two standards. GAC method along with aerated sample and alum dose met all the standards and thus capable of removing all impurities from the sample water.
Recommendations
Physiochemical Treatment Process as an Alternative Treatment Method
Results show that physicochemical method along with GAC adsorption is more efficient than biologically treated method. There are some drawbacks in using GAC along with alum and aerated sample. Firstly, pH level 6.0 should be strictly maintained otherwise total system can be failed. Secondly, size of GAC should be within 0.5-1 mm which rare in market. Improper size could create color and TSS problem in the supernatant and may jam the total filter paper and can be a cause of total failure of this project.
Methodology When the data for all the leachate pollutant variables included in LPI is not available, the LPI can be calculated using the concentration of the available leachate pollutants.
The leachate pollutant variables selected for the LPI are grouped into three components so as to formulate three sub-LPI’s: LPI organic (LPIor), LPI inorganic (LPIin) and LPI heavy metals (LPIhm). Aggregation of the three sub-LPIs to get the overall LPI using the equation: LPI = 0.232 LPIor+ 0.257 LPIin+0.511 LPIhm
.
References
1. Kurniawan, T.A., Lo, W.H. and Chan, G.Y., 2006. Physico-chemical treatments for removal of recalcitrant contaminants from landfill leachate.Journal of hazardous materials, 129(1), pp.80-100. 2. Renou, S., Givaudan, J.G., Poulain, S., Dirassouyan, F. and Moulin, P., 2008. Landfill leachate treatment: Review and opportunity. Journal of hazardous materials, 150(3), pp.468-493. 3. Kumar, D. and Alappat, B.J., 2005. Evaluating leachate contamination potential of landfill sites using leachate pollution index. Clean Technologies and Environmental Policy, 7(3), pp.190-197
