skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Wood ash to treat sewage sludge for agricultural use

Conference ·
OSTI ID:140337
 [1]
  1. Clemson Univ., SC (United States)

About 90% of the three million tons of wood ash generated in the United States from wood burning facilities is being landfilled. Many landfills are initiated tipping fees and/or restrictions on the disposal of special wastes such as ash. The purpose of this work was to evaluate (1) the feasibility of using wood ash to stabilize sewage sludge and (2) the fertilizer and liming value of the sludge/ash mixture on plant response and soil pH. Research showed that wood ash, when mixed with sludge, will produce a pH above 12.0, which meets US EPA criteria for pathogen reduction for land application on non-direct food chain crops. Different ratios of wood ash to sludge mixtures were tested and the 1:1 ratio (by weight) was found to be optimal. Five replications of wood ash from four sources were tested for moisture content, pH and fertilizer nutrients. The pH of the ash/sludge mixture (1:1) on day one ranged from 12.4 to 13.2. In most cases the pH remained the same over a 21 day test or only dropped 0.1 to 0.3 units. Analyses of the mixtures showed that heavy metal concentrations (As, B, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, S, Se, Zn) were low. The 1:1 ash/sludge mixture had a calcium carbonate equivalency of 17%. Green house pot studies using tall fescue grass were loadings of 300 to 750 pounds per acre of TKN-N than for 500 lb/acre of 10-10-10 commercial fertilizer. Plant tissue analysis showed N, P, K, Ca, and Mg levels to be within the sufficiency range for tall fescue.

Research Organization:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
OSTI ID:
140337
Report Number(s):
NREL/CP-200-5768-Vol.1; CONF-9308106-Vol.1; ON: DE93010050; TRN: 93:003926-0068
Resource Relation:
Conference: 1. biomass conference of the Americas: energy, environment, agriculture, and industry, Burlington, VT (United States), 30 Aug - 2 Sep 1993; Other Information: PBD: [1993]; Related Information: Is Part Of First Biomass Conference of the Americas: Energy, environment, agriculture, and industry; Proceedings, Volume 1; PB: 796 p.
Country of Publication:
United States
Language:
English