Study on effect of different Bio chars as adsorbents for Wastewater treatment

Abstract

Biomass based energy conversion systems at different scale produce heat, power, fuels and other by-products which can be used to meet the requirements of domestic and industrial applications. Using different biomass feed stocks; many useful by-products such as bio char can be obtained in addition to energy produced. This study is focused on investigation of effect of activated bio char for wastewater treatment processes. Three bio mass species as albizia, mango pit, and coconut shells were selected; pyrolysis temperature was maintained between 700- 1250 oC. Particle size for all three biomass species was 1.4-2 mm. After a complete cycle, the bio char obtained was cleaned, crushed and activated. Then activated bio char was used as an adsorbent in jar test conducted with palm oil mill effluent. Under constant volume of 300ml, of wastewater, adsorbent weight was varied as 5, 10, 15, and 20g. Performance of each activated bio char was investigated by measuring COD, BOD, Color, TDS, TSS, and the turbidity of the wastewater samples. At the highest adsorbent concentration, bio char from Albizia gives percentage reduction in COD, color, turbidity, TDS and TSS as 87%, 83%, 86%, 76.54%, 76% respectively. Bio char from the mango pit gives percentage reductions as COD; 92%, BOD; 88%, Color; 82.85%, TDS ; 76.59%, TSS; 76.59% and turbidity; 88%, Furthermore, bio char from Coconut shell gives the reduction in COD; 79.1%, BOD; 85.62% Color; 94.12%, TDS; 82%, TSS; 78.53% and turbidity; 96%. The highest color and turbidity removal efficiencies are achieved from the bio char obtained from co-conut shell. In addition, all three bio char types show the better performance efficiencies in the context of waste water treatment. These are readily available, more cost effective and environmental friendly than other commercially available adsorbents.