Anaerobic Digestion Residues Dispose Research

With the number of the large anaerobic plan increased in homeland, more and more anaerobic digestion residues(AD residues) need to be disposed and manage normative. But there is still not a regulation about AD residues in domestic. And less technology in this areas to support the management. Cause AD residues may contained some pollutants like heavy metal ion, persistent organic contaminants, pathogen, etc. if do not deal with that properly, discard that at will, it may be caused the seriously secondly pollution.In this research paper, according domestic status the author designed a system, which can deal with AD residues problem. As the post-treatment technology of the anaerobic digestion plant, the system can make anaerobic digestion plant more popular everywhere. AD residues be separated into sludge and liquid with sedimentation tank. Contained more than 50 percent of organic substance, may some heavy metals ion and pathogens in sludge. Aim to achieve a harmless, energize volume reduction and stabilization purpose, the sludge was composted and crushed for pretreating, compost for 4 days and crushed for 10 min is the best option. Choosed temperature, C/N, TS, as the main parameters experiment anaerobic digestion effect. Proved by the experiment the optimum parameters are temperature was 55℃, C/N was 20, TS was 10%.The liquid from AD residues, contained high concentrate organic, may contained some pollutants like heavy metal ion, persistent organic contaminants. Drained the liquid at will would cause serious environmental pollution. The liquid which was treated in our system can recycle water. The liquid which overflowed from sedimentation tank was absorbed by filter tower. The contaminations in liquid would be absorbed and filtered by biomass sorbent. Proved by experiment that the period of the fist filter tower is about 5 days. And second is 10 days. The tow filter tower decreased the pollutants, the effect was :SS 50.55%, CODCr 41.17%, BOD 35.09%, TN 23.6%, TP 13.24%. The sewage out from the second filter tower went into wetland, and get a further treatment. Wetland makes treat the sewage clean, and get rid of SS 88.34%, CODCr 82.8%, BOD5 88.7%, TN 61.84%, TP 90.19%. the out water from wetland up to recycle standard.