Performance evaluation of different cost effective leachate treatment methods suitable for developing countries

Leachate has a number of environmental problems and it is characterized by high concentration of organic matter, nitrogen, heavy metals, and chlorinated organic and inorganic salts. Organic content of leachate is generally measured in terms of biological oxygen demand (BOD5) and chemical oxygen demand (COD). Higher concentrations of pollutants in leachate are the potential source of contamination of both ground and surface waters. Therefore, it necessitates the proper treatment of landfill leachate prior to discharge into natural water sinks. However, on-site "high-tech" treatment systems are unsustainable to low income countries due to large constructional and operational cost. Hence, there is a particular need for low-cost and low-maintenance leachate treatment systems. The main purpose of this study was to identify the efficiency of different cost effective methods to remove pollutants in leachate. A constructed wetland with an area of 16 m2 planted with typhalatifoliawas used to assess its efficiency in removing pollutants. In addition, column study was conducted to evaluate efficiency of low- cost filter materials as a new method to treat leachate. Different mixtures of sand, clay and activated carbon were tested by loading columns with leachate. The efficiencies of column study and wetland were assessed and constructed wetland was found to perform best and it showed good removal efficiency for COD (88.3%), BOD5 (92.1%) and N03-N (66.7%) while 75.1% of COD, 71.2% of BOD5 and 49.3% of N03-N were removed by the mixture of activated carbon, clay and sand (1:1:1 by volume). The results showed that the wetland and mixture of activated carbon, sand and clay filter materials could be used as low-cost alternatives for the treatment of landfill leachat

Assessment of sub-leachate pollution index (Sub – Lpihm) to determine the heavy metal pollution potential of landfill leachate at Thirupperumthurai landfill site, Batticaloa

Solid waste management may be defined as the discipline associated with controlling the generation, storage, collection, transfer and transport, processing and disposal of solid waste in a manner that is accordance with the best principles of health, economics, engineering, conservation, aesthetics and other environmental consideration. Solid waste management is a major challenge in urban areas throughout the world. Solid wastes are mainly disposed to landfill because landfill is the simplest, cheapest and most cost-effective method of disposing of waste. Leachates from landfill site cause environmental degradation and health hazards due to resultant ground water pollution. A technique to quantify the leachate pollution potential of solid waste landfills on a comparative scale is the use of index known as the leachate pollution index (LPI). The sub-LPIhm is a quantitative tool by which the leachate pollution potential of heavy metal of the landfill can be reported uniformly. The sub-leachate pollution index for heavy metal provides a convenient means of summarizing complex heavy metal pollution data and facilitates its communication to decision makers and the general public. This study was attempted to assess sub-LPIhm of Thirupperumthurai landfill site which is located in Batticaloa district. Leachate samples were collected during the period of September 2015 to January 2016. Samples were analyzed to determine the concentration of heavy metals such as Lead, Zinc, Nickel, Chromium and Arsenic. The sub-LPIhm was calculated by using Delphi technique. The sub-LPIhm values of each points (A, B and C) were 1.4705, 1.4974 and 1.4957 respectively. The overall sub-LPIhm value of Thirupperumthurai landfill site was 1.4997. The results of this study will be used in developing site specific remediation technologies in landfill leachate treatment

Estimation and characterization of municipal solid waste generation in Thirukkovil Pradeshiya Sabha, Ampara District

Municipal Solid Waste is a growing problem in urban areas of Sri Lanka and this problem is aggravated due to absence of proper solid waste management systems at Local Authorities. The management of solid waste requires in depth studies on waste generation and characterization. Thus, an evaluation study was conducted to assess the generation and composition of solid wastes in Thirukkovil Pradeshiya Sabha, Ampara district. Solid waste collected from households and shops by Local Authority were quantified. Then, collected samples were separated into different material categories of wastes. The questionnaire surveying covered 60households in study area. Finally, data were analyzed using Microsoft Excel and SPSS.The results manifested that the average waste generation per household is 2.24 kilogram. Approximately, 16.345 tons of solid waste were found to be generated per day by household sector and has contributed more than 45.64% of the total waste generation. Correlation study revealed that the household waste generation showed a moderate positive correlation (P<0.01) with monthly income and family size. The average composition ofthe household waste in weight basis is organic waste (92.94%), plastic (3.96%), metal (0.86%), glass (1.67%), and hazardous waste (0.57%). Average solid waste generation per shop is 1.56 kilogram.Approximately 74.88 kilogram of solid waste were generated per day and the average composition of the shop waste is organic waste (89.26%), plastic (9.10%), glass (0.94%), metal (0.62%), and hazardous waste (0.046%). The total solid waste collected by the Local Authority is 250.65 tons per week. The average composition of the solid waste collected by Local Authority was organic waste (93.69%), plastic (2.73%), glass (1.03%), metal (0.56%) and hazardous waste (1.96%). The biodegradable material can be utilized for compost making to reduce the materials at home leve