SOLAR DRYING TECHNOLOGY YIELDS CLASS A BIOSOLIDS

摘要

Small wastewater treatment plant in northern California installs solar drying beds to manage 340 dry tons/year of biosolids. THE Town of Discovery Bay, California, a hamlet about 40 miles west of San Francisco, is facing growing population pressures.New home development is expected to double the population. Biosolids from the town s 2.2 mgd wastewater treatment plant, which currently receives about 1.7 mgd of wastewater, had been stored in a lagoon and eventually removed and disposed by a contractor. With the anticipated rise in population, Virgil Koehne, Discovery Bay's general manager, began looking for alternative management options for the approximately 340 dry tons/year of biosolids generated. "I was very aware that our options for disposing of the Class B biosolids we had been producing were becoming increasingly limited," says Koehne. "The State of California issues fewer and fewer Class B permits to farmland owners each year, and it does not allow Class B biosolids to be burned."