Correlation analysis of bacterial growth and heavy metal concentration in composting of leachate sludge and municipal sludge

Abstract

The composting is an alternative solution that can be used to this environmental problem to control the increase in waste generation. The unused leachate waste and municipal sewage sludge could be treated and reused it into compost that can be used for any beneficial purpose such as bio-fertilizer for plant growth. The objectives of this study were to analyze the trend of microbial growth and heavy metal concentration in compost from municipal sewage sludge and leachate sludge. The correlation between both parameters also was identified to determine the relationship between both parameters. Four design ratios were prepared to determine which ratio of compost has the most efficient compost in term of microbial growth and heavy metals concentration. The result showed that mesophilic and thermophilic bacteria population were increases in ratio 1, 2 and 3. The compost of ratio 2 and ratio 3 were found to meet the Malaysian standard of organic fertilizer in terms of the heavy metal concentration. There is correlation between bacteria population and heavy metal concentration in both composts. This composting method could be developed and practised by any institutions or treatment plant so that the amount of sludge waste generated could be reduced and help decreased the environmental pollution crisis in this country.