Anaerobic digestion of Chinese cabbage waste was investigated through a pilot-scale two-stage digester at a mesophilic temperature of 37 ℃. In the acidification digester, the main product was acetic acid, with the ma...Anaerobic digestion of Chinese cabbage waste was investigated through a pilot-scale two-stage digester at a mesophilic temperature of 37 ℃. In the acidification digester, the main product was acetic acid, with the maxi- mum concentration of 4289 mg·L^-1 on the fourth day, accounting for 50.32% of total volatile fatty acids. The oxidation reduction potential （ORP） and NH^＋-N level decreased gradually with hydraulic retention time （HRT） of acidification. In the second digestion phase, the maximum methanogenic bacterial concentration reached 9.6 × 10^10ml^-1 at the organic loading rate （OLR） of 3.5-4 kg VS·m^-3, with corresponding HRT of 12-16 days. Accordingly, the optimal biogas production was 0.62 m^3· （kg VS）^-1, with methane content of 65%-68%;. ORP and NH4^＋-N levels in the methanizer remained between -500 and -560 mV and 2000-4500mg· L^-1, respec- tively. Methanococcus and Methanosarcina served as the main methanogens in the anaerobic digester.展开更多
The biorefinery concept will be important to the energy industry as it allows a multi-process, multi-product biomass based industry. Continued increases in the prices of fossil fuels, the uncertainty of their availabi...The biorefinery concept will be important to the energy industry as it allows a multi-process, multi-product biomass based industry. Continued increases in the prices of fossil fuels, the uncertainty of their availability and the environmental impacts of their extraction are favouring the implementation of sustainable energy production. This article provides a literature review of algal biomass utilisation, process utilisation, technological and economic factors when applying the biorefinery concept to energy intensive industries （whether retro-fitting or new buildings）. This report focuses on opportunities in Finland for innovation, process integration and the development of supply chains whilst using flue gases as a feedstock for the microalgae. Currently, most research is on thermal combustion technologies. Microalgae provide an excellent opportunity to reduce carbon dioxide emissions by mitigation in such industries as pulp and paper. However, a beneficial driver would be feed-in tariffs or green trade certificates but are not necessary for the potential success within the industry. Reducing the overall economic costs with process integration and efficient technologies is beneficial for commercialisation of microalgae biorefineries. Microalgae biorefinery with a high efficiency could help improve the cost effectiveness of microalgae derived biofuels. The remaining algae after harvesting could be used for biogas production, which could be upgraded for vehicle fuel or the production of heat and power. An economically viable microalgae biorefinery with appropriate technologies and integrated for optimum efficiency is therefore possible.展开更多
The possibility of producing biogas and methane from two phases olive pomace was considered using anaerobic digestion and the microbial characteristic of digestate for the agrarian use was analyzed. In the work, the m...The possibility of producing biogas and methane from two phases olive pomace was considered using anaerobic digestion and the microbial characteristic of digestate for the agrarian use was analyzed. In the work, the main aim was to obtain biogas, made from at least 50% methane, and a digestate that can be used in the field of agronomy, from the anaerobic digestion of the substrates. The tests were carried out by digesting different mixtures of the two-phase pomace, mulberry leaves and mud civil wastewater （pre-digested） in a batch system and in anaerobic mesophilic conditions （35 ~C）. The substrates were properly homogenized in order to obtain mixtures of known and uniform composition. The initial and final STi （Total Solids） and initial SVi （Volatile Solids）, the concentration of chemical oxygen demand and total phenols were measured and the process yield （m3/t SV） was quantified with standard procedure. The objectives of the study were the analysis of microbial biodiversity developed during fermentation of mixtures based products and the microbial communities corresponding to Eubacteria, Archaea and Fungiwas analyzed. The suitability of the digestate for agronomical use was evaluated by estimating pathogens bacteria that may be present and by index of inhibition of plant organisms model.展开更多
基金the National Science-Technology Support Plan of China(2014BAD02B04)
文摘Anaerobic digestion of Chinese cabbage waste was investigated through a pilot-scale two-stage digester at a mesophilic temperature of 37 ℃. In the acidification digester, the main product was acetic acid, with the maxi- mum concentration of 4289 mg·L^-1 on the fourth day, accounting for 50.32% of total volatile fatty acids. The oxidation reduction potential （ORP） and NH^＋-N level decreased gradually with hydraulic retention time （HRT） of acidification. In the second digestion phase, the maximum methanogenic bacterial concentration reached 9.6 × 10^10ml^-1 at the organic loading rate （OLR） of 3.5-4 kg VS·m^-3, with corresponding HRT of 12-16 days. Accordingly, the optimal biogas production was 0.62 m^3· （kg VS）^-1, with methane content of 65%-68%;. ORP and NH4^＋-N levels in the methanizer remained between -500 and -560 mV and 2000-4500mg· L^-1, respec- tively. Methanococcus and Methanosarcina served as the main methanogens in the anaerobic digester.
文摘The biorefinery concept will be important to the energy industry as it allows a multi-process, multi-product biomass based industry. Continued increases in the prices of fossil fuels, the uncertainty of their availability and the environmental impacts of their extraction are favouring the implementation of sustainable energy production. This article provides a literature review of algal biomass utilisation, process utilisation, technological and economic factors when applying the biorefinery concept to energy intensive industries （whether retro-fitting or new buildings）. This report focuses on opportunities in Finland for innovation, process integration and the development of supply chains whilst using flue gases as a feedstock for the microalgae. Currently, most research is on thermal combustion technologies. Microalgae provide an excellent opportunity to reduce carbon dioxide emissions by mitigation in such industries as pulp and paper. However, a beneficial driver would be feed-in tariffs or green trade certificates but are not necessary for the potential success within the industry. Reducing the overall economic costs with process integration and efficient technologies is beneficial for commercialisation of microalgae biorefineries. Microalgae biorefinery with a high efficiency could help improve the cost effectiveness of microalgae derived biofuels. The remaining algae after harvesting could be used for biogas production, which could be upgraded for vehicle fuel or the production of heat and power. An economically viable microalgae biorefinery with appropriate technologies and integrated for optimum efficiency is therefore possible.
文摘The possibility of producing biogas and methane from two phases olive pomace was considered using anaerobic digestion and the microbial characteristic of digestate for the agrarian use was analyzed. In the work, the main aim was to obtain biogas, made from at least 50% methane, and a digestate that can be used in the field of agronomy, from the anaerobic digestion of the substrates. The tests were carried out by digesting different mixtures of the two-phase pomace, mulberry leaves and mud civil wastewater （pre-digested） in a batch system and in anaerobic mesophilic conditions （35 ~C）. The substrates were properly homogenized in order to obtain mixtures of known and uniform composition. The initial and final STi （Total Solids） and initial SVi （Volatile Solids）, the concentration of chemical oxygen demand and total phenols were measured and the process yield （m3/t SV） was quantified with standard procedure. The objectives of the study were the analysis of microbial biodiversity developed during fermentation of mixtures based products and the microbial communities corresponding to Eubacteria, Archaea and Fungiwas analyzed. The suitability of the digestate for agronomical use was evaluated by estimating pathogens bacteria that may be present and by index of inhibition of plant organisms model.
