Sand intermittent filtration technology for safer domestic sewage treatment

Abstract

The present investigation was undertaken to find out pollution reduction potential of Sand intermittent filtration bed in term of physico-chemical and microbiological characteristics of domestic sewage. The domestic sewage was filtered through Sand intermittent filtration beds of mixture of sand and soil at different ratio i.e. 1:1; 1:3; 3:1 and one set of 100% of each sand and soil were also taken. Results revealed that there was a significant pollution reduction in various physico-chemical and microbiological parameters of domestic sewage in sand soil mixture. In general sand and soil beds have shown better performance than only sand or soil bed for sewage treatment. Albeit Sand soil bed of 2 feet depth has been found better in term of pollution reduction ability than other depths used in the present study, but variation of pollution reduction potential has been recorded for different parameters in sand and soil bed of the same ratio. Mixture of Sand soil bed at ratio 3:1 has yielded better results in general than all other used ratio but for certain parameters stands equal with 1:1 ratio. Maximum percentage of reduction in pH i.e. 16.7% and in Temperature 27.9% was found at 2 feet depth in mixed sand and soil bed of 1:1 ratio. Maximum pollution reduction potential of intermittent filtration bed was recorded at 2 feet depth of sand and soil mixture at ratio of 3:1. Percentage of pollution reducing potential was found in CO2 83.4%, BOD 72.5%, COD 69.9%, Total alkalinity 37.9%, Total solids 88.5%, Total dissolved solids 86.1%, Total suspended solids 91.2%, MPN 82.4% and SPC 78.4%. Minimum reduction ability was found in 100% sand and soil bed without mixture.

Journal of Applied Sciences and Environmental Management Vol. 10(1) 2006: 73-77