Sulfur minimization in bacterial leaching

摘要

The production of sewage biosolids in Ontario in 1989 was estimated to be 7 million m~3 (1850 million US gallons) of wet sludge per year~1. Of this amount, land application accounts for between 20 and 30 percent of the total.~(1,2) In the United States, land application is the most popular disposal option used by small and mid-sized plants~3. Unfortunately, the use of sewage biosolids on agricultural land is often prohibited becasue of heavy metal contamination of the biosolids. Various metals may limit the application of biosolids to agricultural land. In Ontario cadmium is frequently the problem~2, in Quebec copper contamination is more common~4, while in the UK, zinc, copper and nickel are the usual cause for rejection of the biosolids.~5