Study On The Technology Of Synchronizing Leach Heavy Metals With Strengthen Hydrolysis-acidification

The heavy metal pollution in the livestock manure has received increasing attention. How to enhance the process capacity of livestock manure and avoid heavy metal pollution is a problem to be solved urgently. This paper adopted two-phase anaerobic technology to remove heavy metal in the livestock manure,add acid into the acidogenesis phase of two-phase anaerobic digestion to enhance efficiency,on the one hand, the reaction rate of hydrolysis and acidogenesis was improved,on the other hand, the heavy metal in the livestock manures was leached into liguidoid and could be removed and recycled by crystallization, then the fementation liquid was used for gas production.In this way,not only the process capacity of livestock manure increased,but also reach the goal of removing heavy metals. The main conclusions of this paper were as follows.(1) The results of studies on the factors of hydrolysis and acidogenesis process showed that the the optimal temperature conditions of 10% TS composite organic material was 35℃,acidification rate decreased with the increase in TS.(2) The optimal conditions of 10% TS chicken manure in adding acid acidogenesis process was that the 20%HCL amount used 2.1%,initial pH 5,temperatures 35℃,retention time 3d.On this conditions,the CODs and VFA from hydrolysis and acidogenesis process was increased by 15% and 20% compared with the conditions without acid.(3) The optimal conditions of heavy metal leaching was that the 20%HCL amount used 3.5%, initial pH 4, retention time 3d.Compared with bioleaching and chemical leaching, the way of adding acid acidogenesis leaching need less content of acid ,retention time and treatment costs. (4) This paper presented that the introduction of disintegration in ADM1 is unreasonable, hydrolysis is the first progess of anaerobic digestion,this paper adopted Monod equation to simulate the process of hydrolysis and acidogenesis of 10%TS chicken manure,which proved that the rate of hydrolysis and acidogenesis can be increased by adding acid from the dynamic point of view, and got dynamic equation on different acid consumption conditions(5) This paper analysed the actual running effect of two-phase anaerobic reactor,on the conditions that initial pH 5,temperature 35℃, retention time 3d,the average acidification rate was 14.9 %,the average total removal rate and unsteadystate removal rate of Cu,Zn and Cd was 31% and70%,47% and 74%,40% and 60% separately,the COD and VFA removal rate of methanogenic reactor was 80% and 95% separately.After running, The diameter and inorganic level of granular sludge in the reactor increased and so the number of methanogenic bacteria in granular sludge.