Organic manures sewage sludges

Farm manures, sewage sludges, domestic composts—heavy metals, viruses, pathogens, organic pollutants... 

Materials handled include food products, chalk, coal, organic chemicals, clays, spent coffee grounds, sewage sludge and chicken manure. Where exhaust gases have unpleasant odours, after-burners can be supplied to raise the temperature and bum off the organic and particulate content causing the problem. 

Figure 4.2. Carbon released as C02 from unamended soil and soils amended with pig slurry (PS), poultry manure (PM), cattle farmyard manure (FYM), aerobic sewage sludge (SS), municipal solid waste fuse compost (RC), and rye straw (RS) at a rate of lOgkg1 during incubation at 22 °C. Reprinted from Levi-Minzi, R., Riffaldi, R., and Saviozzi, A. (1990). Carbon mineralization in soil amended with different organic materials. Agric. Ecosyst. Environ. 31, 325-335, with permission from Elsevier.

Figure 4.3. Gel permeation chromatograms of humic acids isolated from a soil either unamended (A) or amended with 25tha 1yr 1 of cattle manure for 4 years (B) and 25, 50, and 100tha 1yr 1 of sewage sludge for 4 years (C, D, and E, respectively). Reprinted from Piccolo, A., Zaccheo, E, and Genevini, P. G. (1992). Chemical characterization of humic substances extracted from organic-waste-amended soils. Bioresource Technol. 40, 275-282, with permission from Elsevier.

There are two major pathways responsible for decomposing organics (plant residue, manures, synthetic organics, sewage sludges, etc.) in the soil-water environment. One pathway involves aerobic processes, and a second involves anaerobic processes. During aerobic decomposition, carbohydrates are converted to carbon dioxide and water as follows ... 

In China and other countries, the application of C-rich organic materials to heavy metal-contaminated soils is a common practice. However, the potential risk of metal mobilization should not be overlooked when metal dissolution facilitated by DOM released from organic wastes exceeds metal immobilization caused by particular organic matter. Figure 10.8 demonstrates that addition of DOM derived from green manure, pig manure, peat, rice litter, and sewage sludge to a Cu-contaminated soil caused an increase in soil water-soluble Cu contents. Compared to the control (no... 

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