Related Experiment Video
Updated: Aug 10, 2026

Agar-Block Microcosms for Controlled Plant Tissue Decomposition by Aerobic Fungi
Published on: February 3, 2011
Synergetic effect of gamma irradiation and moisture content on decontamination of sewage sludge
M Al-Bachir1, M A Al-Adawi, M Shamma
1Department of Radiation Technology, Syrian Atomic Energy Commission, P.O. Box 6091, Damascus, Syria. malbachir@aec.org.sy
Abstract:
Samples of concentrated municipal sewage sludge, stored for 2, 4 and 6 months, with moisture contents of 2%, 20%, 40%, 60%, and 80% were exposed to doses of 0, 1, 2, 3, 4 and 5 kilogray (kGy) of gamma irradiation. Immediately after irradiation, total microbial count and bacterial pathogens in sewage sludge were determined. The results indicated that in all tested sewage sludge samples, bacterial pathogens including Enterobacter sp., Klebsiella sp., Salmonella sp., and Escherichia coli were initially detected. All doses of gamma irradiation reduced the total counts of microorganisms. D(10) of total count decreased with increase in the moisture content of the sewage sludge. The lowest lethal dose for tested bacterial pathogens was 5 kGy in air dried sewage sludge. In addition for wet sewage sludge having more than 40% moisture, the lethal dose was 1 kGy, for samples taken at different storage periods 2, 4 and 6 months, and therefore the cost per unit could be decreased to half when wet sewage sludge (about 50% moisture) was used.
More Related Videos
15:19Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
09:39Production and Testing of Moisture Behavior and Thermal Properties of Rapeseed Straw and Ganoderma resinaceum Mycelium Bio-Composites
Published on: September 5, 2025
Related Concept Videos
Methods of Sterilization I: Physical Methods
Steam sterilization uses non-toxic, low-cost moist heat in the form of saturated steam under pressure, which is fast, microbicidal, and sporicidal, and quickly warms and penetrates fabrics. Autoclaves, or steam sterilizers, expose each item to direct steam contact for a predetermined time at the necessary...
Physical Methods for Controlling Microbial Growth: Radiation and Filtration
Microbial Bioremediation of Uranium
Microbial Bioremediation of Pesticides
Microbial Wastewater Treatment
Biological Treatment of Effluent and Waste Water