Shredded Rubber Tires as a Bulking Agent in Sewage Sludge Composting

Abstract

This study evaluated shredded rubber tires mixed with raw primary sludge to determine the optimum particle size and mix ratio for efficient composting. Of the three sizes and mix ratios tested, the 1.27-2.54 cm size and the rubber chip to sludge mix ratio of 2 : 1 were found to be optimum. Anaerobically digested and secondary biological sludges were then composted with the optimum size rubber chips. Due to their high moisture content and low C/N ratio, all three sludges required a moisture absorbing amendment and supplemental carbon. Sawdust was tested and found to be a suitable amendment. Heavy metal levels increased due to the concentrating effect as organic matter was decomposed. Rubber chips contributed zinc and iron to the finished compost. Although elevated after five cycles, the increases in zinc and iron were not high enough to limit the use of shredded rubber in composting sewage sludge.

Keywords

Composting sludge rubber tires size of shreds zinc iron.

Get full access to this article

View all access options for this article.

References

Allison, L.E. 1960, Wet combustion apparatus and procedure for organic and inorganic carbon in soil, Soil Science Society of America Proceedings, 24, 36-40.

Methods of Soil Analysis (1982), Part 2—Chemical and Microbiological Properties, 2nd Edition. American Soceity of Agronomy, Madison, Wisconsin.

Harding, G.T. , Romano, L.S. & Epstein, E. (1983), Woodchip rubber tire blend works in Windsor, BioCycle, 24 (6), 44-46.

Higgins, A.J. , Singley, M.E. , Nocitra, N. , Callanan, K. , Whitson, B. & Singh, A. (1980), Shredded rubber tires as a bulking agent, BioCycle, 21 (6), 20-23.

Higgins, A.J. , Kasper, V., Jr. , Derr, D.A. , Singley, M.E. & Singh, A. (1981), Evaluation of screens for sludge composting, BioCycle, 22 (3), 22-26.

Higgins, A.J. (1983), Reducing costs for bulking agents, BioCycle, 24 (5), 34-38.

Higgins, A.J. , Suhr, J.L. , Rahman, M.S. , Singley, M.E. & Rajput, V.S. (1986), Shredded Rubber Tires as Bulking for Composting Sewage Sludge. U.S. Environmental Protection Agency Project No. CR-810255-01 . Water Engineering Research Laboratory, Office of Research and Development, U.S. EPA, Cincinnati, Ohio.

Mortvedt, J.J. & Giordano, P.M. (1975), Response of corn to zinc and chromium in municipal wastes applied to soil, Journal of Environmental Quality, 4, 170-174.

Sikora, L.J. , Willson, G.B. , Collacicco, E. , Parr, J.F. , Frankos, N.H. & Trager, J. (1980), Materials balance in sewage sludge composting by the beltsville aerated pile method. In Proceedings of Conference on Municipal and Industrial Sludge Composting, Information Transfer Incorporated, Silver Springs, MD, U.S.A.

10.

Singley, M.E. , Higgins, A.J. & Frumkin-Rosengaus, M. (1982), Sludge Composting and Utilization: A Design and Operating Manual. New Jersey Agricultural Experiment Station, Cook College, Rutgers, The State University of New Jersey , New Brunswick, New Jersey, U.S.A.

11.

Standard Methods for the Examination of Water and Wastewater (1971), 13th edn. APHA-AWWA-WPCF, American Public Health Association, Washington, D.C., U.S.A.

12.

Williams, H. (1980), Official Methods of Analysis of the Association of the Official Analytical Chemists, 13th Edn, AOAC, Washington, D.C.