Enhancing Biogas Production by Using Slaughterhouse Wastewater and Domestic Sludge to Cover Energy Demand for Wastewater Treatment Plant in Nablus Governorate
جامعة النجاح الوطنية
In this study, enhancement in biogas production from using Co-digestion of slaughterhouse wastewater (SHW) mixed with primary sludge (PS) was evaluated, and compared with biogas production from digest the SHW, and PS individually. In order to carry out this evaluation, lab experiments were conducted under mesophilic condition (35±2°C) by using bench scale batch digesters at laboratories of An-Najah National University. In all experiments, total solids (TS), total volatile solids (VS), and pH, alkalinity (ALK), also volatile fatty acids (VFA) were measured before and after digestion process. Further to these, the daily biogas and methane (CH4) production were also measured. Results indicated that Co-digestion system achieved the maximum biogas yield which was (499.8 Nml Biogas /g VS fed), while the biogas yield for digest each of PS, and SHW in individual digester were (411.5 Nml biogas per g VS fed, and 433.8 Nml biogas /g VS fed), respectively. It was found that the implementation of the Co-digestion of SHW with PS has improved the biogas yield comparing with what can be achieved by digest SHW and PS separately. Results also revealed that the CH4 yield from the Co-digestion was the maximum value of 220.3 Nml CH4/g VS fed, while the value of 200.1 Nml CH4/g VS fed was produced from digest PS separately, and the lowest value of 186.9 Nml CH4/g VS fed was achieved in case of SHW digestion separately. A result that prove along with the accumulation of VFA in the reactor the occurrence of inhibition in methanogenesis activity when the SHW was digested as individual substrate. The biodegradability of organic matter in Co-digestion system was found greater than SHW digestion individually, since organic removal was 44.4% in case of Co- digestion system, and it was 29.1% in case of digest SHW individually, while the maximum degradation was in case of digest PS individually which was 49.0%, and this make an indication that PS sample has less complex substrate comparing with SHW and Co-digestion samples. Results proved that implementation of anaerobic digestion to digest SHW, represents an alternative for biogas production, especially when it was applied in Co-digestion system. This study results has given useful answers for improving the efficiency of West Nablus Wastewater Treatment Plant (WN-WWTP) and about the appropriateness of SHW treatment to enhance the waste biodegradation and enhance biogas production within anaerobic digestion stage in the treatment plant, without causing financial, operational, technical, and environmental impacts on the treatment system.
Biogas, Methane, Anaerobic digestion, Co-digestion, Domestic Sludge, Slaughterhouse wastewater, Blood, WWTP