Green energy production from chicken manure with closed loop membrane supported biogas process

Chicken manure (CM) which has been generated from an important economic activity in our country has serious technical problems in biogas production due to its high nitrogen content (CM contains 5-6% nitrogen). Nitrogen impose risk of inhibition to anaerobic bacteria during the biochemical degradation of organic material. Therefore, the most common application method is either the dilution of raw material with fresh water or co-digestion with other available organic substrates in order to dilute the raw chicken manure's nitrogen content down to a non-toxic level. The addition of huge level of fresh water becomes a residual after fermentation and it needs to be stored for a long time of period until it can be used as fertiliser. This approach has high capital cost for storage and other practical problems in operation. In this thesis, "the use of nitrogen selective membranes" is aimed in order to remove the nitrogen from the circulation line and de-nitrogenated circulation water could be continuously used for many times as feed water in the inlet. Thereby, fresh water requirement would be decreased significantly and need for huge amount of storage investment would also be eliminated. For this purpose, the thesis began with the characterization chicken waste and in the first part of the project, batch membrane studies focused on the selection of appropriate membrane and optimization of operating conditions. Afterwards, continuous membrane operation was carried out in connection with operating fermentor. Within this study, it was reported that the use of membrane supported biogas production systems could provide a feasible solution not only at national but also international level in terms of recovery of bioenergy content of chicken manure which is an improtant alternative energy potential. Keywords: biogas, membrane, chicken manure, renewable energy.