The Big and Small of Biosolids Composting

Bimlids ampstmg wntinues to be one of the more popular methods of biosolids management utilized in North America. According to the most recent BioCycle survey (Goldstein, 1995), 228 biosolids composting facilities were operational by the end of 1995 in the United States. The aerated static pile is still the most popular biosolids technology used with 101 facdities or 44% of the total being that variety. Many communities valuating biosolids management options are cmcemed with the cost of cornposting biosolids, the technolog used, and odors associated with the process. The technology used keds to have flexibility to manage varying quantities and characteristics of biosolids. Composting facilities must be operated free of odor problems and they must be able to process materials in a cost-effective manner. Two new biosolids ampstmg facilities which utilize the aerated static pile method of composting began operation in 1995. One facility is a large 28 dry ton per day ampstmg facility that p'ocesses yard wastes as well as biosolids in Davenport, Iowa. This facility is totayr enclosed f o r d OQr control. The other is a smaller 5.5 dry ton per day facility which is owned and operated by the Hamsonburg-Roclangtuun R e g i d Sewer Authority in Mount Crawford (Harrisonburg area), Virgma. Tlus paper pvi&s a dehled desaiption of the equipment and facilities included in each of these two static pile operations, provides a summary of the initial stages of operation, and provides a dehled cost comparison of actual capital costs and operation and maintenance costs of the two facilities. This dormation will provide valuable insight to various communities considering cornposting as part of their biosolids management programs.