| While the continuous urban sewage treatment capacity rising of China, municipal sludge which produced in the process of wastewater treatment increased dramatically in recent years. Reasonable ways to dispose of municipal sludge has become a very urgent task. According to incomplete statistics, the production of municipal sewage sludge (dry sludge) of China has reached 30 million tons in 2008. Main methods of sludge disposal at this stage were landfill, incineration, discarded into the sea and land use. The principle of sludge disposal was stable, innocuous, reduction and recycling, sludge recycling was in line with our sustainable development strategy and was conducive to the establishment of circular economy.Land use was the mian methods of sludge recycling. But the pollution risk of organic pollutants and heavy metals in municipal sewage sludge constrained the large-scale land use of municipal sewage sludge. Brewery sludge was one of typical municipal sewage sludge.Relativing to the general municipal sewage sludge, brewery sludge has the less content of heavy metals and organic pollutants, the higher organic content, of organic matter, protein, and nitrogen, phosphorus; Calcium and magnesium were rich in it, which was more suitable for land use. For deal with this problem in a safe, reliable, under the premise of avoiding secondary pollution, this study builded complex bacterium which could remove odor during composting, curtailing compost process. The goal of the study was to research new technology to achieve the brewery sludge for land use by composting. So that it could help eliminate the pollution of brewery sludge, and reduce the agricultural production of fertilizer input costs.Otherwise, this study investigated the degradation of polycyclic aromatic hydrocarbon by composting of inoculating flora of DF-1 into municipal sewage sludge. It expanded the scope of application of flora of DF-1 to create feasibility.The conclusions of this study were following:1 Building high-performance bacterium for brewery excess sludge composting and the identification advantage strain of itDomesticating the bacterium of pickles,the bacterium at the bottom of haystack for years and the bacilli in rapeseed oil crushing workshop soil. The bacterium which could degradate of cellulose and eliminate odor was obtained. This bacterium was named DF-1, its function was stability.Bacteria and fungi were dominant strain of bacterium DF-1, while actinomycetes were not dominant bacteria. The dominant strain were Lactococcus lacti,Candida tropicalis and Trichoderma viride. The growth curves of three dominant strains were studied.2 The new brewery excess sludge composting technics and the optimization results of main parameters of brewery excess sludge composting, and the pilot technics of new brewery excess sludge compostingThe factors of composting process that affected the generation rate of humic acid sequence were:C/N ratio>amount of bacterium DF-1>moisture content. Visual analysis of the optimum conditions for composting process was:C/N ratio of 30:1, bacterium DF-1 adding amount of 0.5%, moisture content of 60%.Using rapeseed meal as a brewery sludge conditioning agents, brewery sludge and rapeseed meal were in accordance with mass ratio of 4:1 ratio (adding 0.5%mass fraction of urea, adjust C/N ratio 30:1, moisture content of 60%) in a mixture.50 kg was a unit which was packing a bag and sealed for fermentation. Or Using chicken manure as a brewery sludge conditioning agents, brewery sludge and chicken manure were in accordance with mass ratio of 1:1 ratio (adding 0.2% mass fraction of urea, adjust C/N ratio 30:1, moisture content of 60%) in a mixture.50 kg was a unit which was packing a bag and sealed for fermentation.Both of the product of composting were maturity after 21 d, which was loose and odorless. hygiene indicators had reached the national standard. Compared with traditional composting, this technology could remove water-soluble organic carbon for 62.2% in 21 d (chicken manure and sewage sludge compost water-soluble organic carbon removal rate could reach 54.1% in 21d). This technology fitted the requirements of "urban sewage treatment plant pollutant discharge standard" (GB18918-2002) on organic matter degradation. The quality of reduction of composting was 35% or more. The germination index reached 70%. And the product of composting was stable.3 The mechanism of bacterium DF-1 inoculated with brewery sludge compostingThe total number of bacteria,fungi and actinomycetes first increased and then decreased change in trend in the composting process of two compost pile. The total number of fungi and actinomycetes were significantly less than the total number of total number of bacteria. The change in the number of three kinds of microorganisms of brewery sludge and chicken manure pile was larger than the number of three kinds of microorganisms of brewery sludge and rapseed meal. The temperature-rising period in the two compost pile, the advantages of micro-organisms of DF-1 Lactococcus lactis, Candida tropicalis, and Trichoderma viride could be detected. Lactococcus lactis was detected in high temperature period of composting. Trichoderma viride was detected in cooling period and maturity period of composting. It showed there was an alternating process of evolution in the composting process of the advantage of micro-organisms of DF-1. And this process and the compost material composition and degradation of closely related to the situation.4 Biodegradation of polycyclic aromatic hydrocarbons in municipal sewage sludge after the inoculation bacterium DF-1 by compostingThe fate of 16 polycyclic aromatic hydrocarbons (PAHs) during the 94 days of composting of municipal sewage sludge with rapeseed meal was studied. The total PAHs calculated from the sum of the amounts of the 16 PAHs in the initial mixture of municipal sewage sludge was about 1.792 mg·kg-1. Then the content of total 16 PAHs was 0.153 mg·kg-1 at the final of composting. The level of total PAHs fell by about 91.5%(P<0.05) at the end of composting. The tight adsorption of PAHs with high molecular weight (N≥4) plus phenanthrene makes them inaccessible for biodegradation. The high molecular weight PAHs showed a greater reduction of their bioavailability than low molecular weight (except benzo[b]fluoranthene).
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