CONVERSION OF THE TAR WATER FROM SYNGAS PLANT INTO BIOGAS

• Дата: 2017
• Автор: Kliys, V.
• Формат: Стаття
• Мова: Ukrainian
• Опубліковано: Institute of Renewable Energy National Academy of Sciences of Ukraine 2017
• Теми: biogas; biomass; anaerobic digestion; substrate; gasification; tar water
• Онлайн доступ: https://ve.org.ua/index.php/journal/article/view/28
• Назва журналу: Vidnovluvana energetika

The purpose of the work is to determine and analyze the yield of methane and dynamics of methane formation during the digestion of manure wastes with the condensate from syngas   plant, which contain an insoluble tar. Evaluate the degree of destruction of manure organic matter and the degree of destruction of condensate organic matter. Four substrates containing condensate from 0% to 8% were prepared for experimental studies. One additional substrate was also prepared which contained only inoculum to determine the residual methane in the inoculum. Cow manure was taken as a manure wastes. The digestate was taken after anaerobic digestion of a mixture of cow manure and condensate from syngas plant as an inoculum. The condensate containing the insoluble tar was obtained during the gasification of chips in a gasifier of a reverse process with a moving gasification zone. The value of the volume of produced biogas was determined by the method of extrusion. The value of COD was determined by the photometric method. Parameters of the digestion were selected by the method of least squares approximating the experimental data to the Gompertz dependence with a limited growth potential. The mass concentration of dry matter and ash content were determined according to standard methods. The value of the volumetric carbon dioxide concentration was measured using a chemical gas analyzer. The pH of the medium was measured with pH meter. The experiment under anaerobic conditions lasted for 60 days at a temperature maintained in the range from 34.8 ºС to 35.2 ºС. For substrates in which tar water was introduced, a significant increase in the lag phase from 4,2 days in the control substrate (without tar water) to 12,9-19,8 days in model substrates (with tar water) was observed. The yield of methane for model substrates was lower than in the control ones until 32-39 days of digestion. By the end of the experiment the yield of methane in the model substrates was higher in 1.25-1.31 times than in the control ones. It was found that the degree of destruction of manure organic matter decreases and the degree of destruction of condensate organic matter increases. Summing up the experimental results one can state that it is possible to anaerobe utilize condensate in combination with manure wastes under a mesophilic regime.