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991.
Min-Gu Lee Dongwoo Kang Hoyong Jo Jinwon Park 《Journal of Material Cycles and Waste Management》2016,18(3):407-412
In this study, we propose a process making calcium carbonate and calcium sulfate and recovering absorbent using ammonia absorbent, carbon dioxide, and industrial waste. The main objective of this study is to confirm the possibility of carbon capture and utilization based on waste materials. We assumed desulfurization gypsum and construction waste (ready mixed concrete washing water, waste concrete, etc.) are CaSO4, Ca(OH)2, respectively. And concentration of simulated carbon dioxide gas was 15 vol% similar to flue gas. Calcium carbonate was produced by combination reaction between ionic CO2 in absorbent and metal ion in the solid waste. Experiments were conducted at normal temperature and pressure. Furthermore, the generated products were characterized by X-ray diffraction, and scanning electron microscope. 相似文献
992.
Anh Van Ngo Ha Thi Nguyen Chieu Van Le Rajeev Goel Mitsuharu Terashima Hidenari Yasui 《Journal of Material Cycles and Waste Management》2016,18(2):239-247
Microbial response on volatile fatty acids (VFAs) is a key for methane fermentation processes since accumulation of VFAs often causes an acidic failure, especially treating such organics as food wastes composed of mostly readily biodegradable materials. To evaluate the impact of VFA accumulation, a lab-scale continuous experiment was performed for 110 days with sequential feeding of heterogeneous food wastes. When the volumetric loading rate was increased from 6 to 8 kg-COD/m3/day, a sudden decrease of methane production was observed with an accumulation of acetate and propionate in the fermenter. After discontinuation of feeding for 10 days, the digestate in the fermenter was centrifuged and washed with tap water to reduce the VFAs to be acceptable concentration below 1000 mg-COD/L. Nevertheless, no recovery of methane production was observed and VFA concentrations consistently increased. To model the event, a modification of ADM1 was made assuming the methanogens in the fermenter were irreversibly inactivated under very high VFA. Also considering the different nature of the fed food wastes over 11 samples, decomposition kinetics of individual food wastes were manipulated. The modified ADM1 with methanogenic activity decay reasonably reproduced the responses for soluble material concentrations and methane gas production rate over the experimental period. 相似文献
993.
Dongjin Lee Jisu Bae Jungu Kang Kiheon Kim 《Journal of Material Cycles and Waste Management》2016,18(3):445-454
This study was to find out potential of methane yield on food waste and food waste leachate as biomass in Korea. The seven biogasification facilities were selected for comparison of theoretical methane yield and actual methane yield. The theoretical methane yield was calculated based on organic constituents (carbohydrate, protein, fat) and based on element analysis. The actual methane yield was investigated based on volatile solids and CODcr. Theoretical methane yields by organic constituents were 0.52 Sm3CH4/kg VS and 0.35 Sm3CH4/kg CODcr and these by element analysis were 0.53 Sm3CH4/kg VS and 0.36 Sm3CH4/kg CODcr. Actual methane yields were 0.36 Sm3CH4/kg VSin and 0.26 Sm3CH4/kg CODcrin. Considering the average removal efficiency of organic materials of seven FWL biogasification facilities, actual methane yields were 0.48 Sm3CH4/kg VSrem and 0.33 Sm3CH4/kg CODcrrem. Methane yield by organic constituents is very similar to that by element analysis and actual methane yields of volatile solids and CODcr were similar to theoretical value. The actual methane yield in this study showed approximated boundary values with previous other references which conducted in lab-scale or biochemical methane potential (BMP) tests. In conclusion, Korean food waste and food waste leachate have sufficient potential of methane yield in the ongoing biogasification facilities. 相似文献
994.
Ye Sun Yuan Meng Xiaoyan Guo Tianle Zhu Hongju Liu Wenpei Li 《Journal of Material Cycles and Waste Management》2016,18(4):618-624
Experiments were conducted using a bubbling reactor to investigate nitrogen oxide absorption in the calcium sulfite slurry. The effects of CaSO3 concentration, NO2/NO mole ratio and O2 concentrations on NO2 and SO2 absorption efficiencies were investigated. Five types of additives, including MgSO4, Na2SO4, FeSO4, MgSO4/Na2SO4 and FeSO4/Na2SO4, had been evaluated for enhancing NO2 absorption in CaSO3 slurry. Results showed that CaSO3 concentration had significant impact on NO2 and SO2 absorption efficiencies, and the highest absorption efficiencies of SO2 and NO2 could reach about 99.5 and 75.0 %, respectively. Furthermore, the NO2 absorption was closely related to the NO2/NO mole ratio, and the existence of NO2 in flue gas may promote NO absorption. The presence of O2 in simulated flue gas was disadvantage for NO x removal because it can oxidize sulfite to sulfate. It was worth pointing out that FeSO4/Na2SO4 was the best additive among those investigated additives, as the NO2 removal efficiency was significantly increased from 74.8 to 95.0 %. IC and in situ FTIR results suggest that the main products were NO3 ? and NO2 ? in liquid phase and N2O, N2O5 and HNO3 in gas phase during the CaSO3 absorption process. 相似文献
995.
Kazuyuki Oshita Xiucui Sun Koji Kawaguchi Kenji Shiota Masaki Takaoka Kazutsugu Matsukawa Taku Fujiwara 《Journal of Material Cycles and Waste Management》2016,18(4):608-617
Ash produced from the combustion of livestock manure contains large amounts of phosphorus (P), which is an important resource as a fertilizer. Some studies have extracted and recovered P from incinerated biomass ash using inorganic acid or alkaline agents, which produce wastewater that requires treatment and is expensive due to the cost of chemicals. Livestock manure ash contains not only P, but also water soluble salts, which could be a negative influence on plant growth and shall be preferably removed from the recovered fertilizer. In this study, we removed salinity from cattle manure incineration ash by simple aqueous leaching, while retaining the P content. The optimal condition was a 20 min leaching time at a liquid/solid (L/S) ratio of 10 mL g-ash?1. Under this condition, over 90 % of Cl and 20 % of Na in the original ash was removed, while over 99 % of the P was retained in the leached residue. The leached residue met the fertilizer standard in Japan in terms of citrate soluble fertilizer components and contained few heavy metals. X-ray analyses of the ash indicated that Cl was mainly present as KCl in the original ash, while P was mainly present as Ca compounds in the ash. 相似文献
996.
Waste-to-energy is one effective waste management approach for a sustainable society. The purpose of this study was to clarify the potential for energy recovery and greenhouse gas (GHG) reduction that could be achieved by introducing anaerobic digestion (AD) facilities in the process of reconstructing aging incineration facilities in Japan. Using statistical data from 1068 incineration facilities, four future scenarios were considered and compared with the current situation. As results, compared with the current situation the amount of electricity generated could increase by 60 % in 2030, by combining AD facilities for food waste with new, high-efficiency incineration facilities for remaining municipal solid waste (MSW). From a life cycle perspective, net energy recovery in 2030 was approximately three times greater than in 2011, and GHG emission could be reduced by 27 %. The introduction of AD facilities is attractive for small authorities, which currently treat <100 t/day of MSW through incineration facilities without energy recovery. An AD facility is also beneficial for large authorities. On the contrary, in middle-scale authorities that treat 100–299 t/day of MSW, the reconstruction of incineration facilities to include electricity production capabilities requires careful consideration, because it will significantly influence energy recovery and GHG reduction effects. 相似文献
997.
Joung-Soo Sun Jin-Man Kim Jong-Hyun Sung 《Journal of Material Cycles and Waste Management》2016,18(4):752-762
Currently, wet bottom ash is not sufficiently utilized due to its content of unburned coal, chloride and moisture. In contrast, bottom ash discharged from the recently introduced dry process spends a longer time on the clinker conveyer in the lower part of the boiler and consequently contains a significantly smaller amount of unburned coal. Consequently, it has high potential for use as a lightweight aggregate for construction material because of properties such as high porosity, low unburned coal content, non-chloride, and non-moisture. However, it is not frequently used for construction because the ash particle has a flat and thin shape, coarse surface and unfavorable structural strength. Against this backdrop, this study has conducted a range of experiments to identify the shapes, structure, density, absorption, percentage of floating particles, unit volume weight, solid volume, characteristics of air bubbles and micro pores, crushing strength of bottom ash, and the following results were observed. Though the dry bottom ash has sharp and angular edges, its flat and thin shapes lead to vulnerable structures. Dry bottom ash of the size of 0.6 mm or larger has 50–60 % of the total pore rate and 30–50 % of the closed pore rate. Considering these qualities, by removing the relatively fragile surface parts and making the particles more globular, dry bottom ash can be used as a lightweight aggregate for construction field having outstanding performance in terms of light weight and insulation. 相似文献
998.
Along with the world population increase, meat requirement has been also increasing; thus, massive livestock manure has been released leading to problems due to surplus nutrients. To overcome this situation, we should consider availing some nutrient removal or reuse technology. The commonest way to recover resources from livestock manure is by producing liquid fertilizer and compost. However, some technologies are required to make it easier and safer for transportation and handling of manure fertilizer due to various problems such as poor fertilization quality with low maturity, emission of odor, nutrient loss, and disharmony due to fluctuating seasonal and regional supplies and demands. In this study, available technologies for resource recovery from animal wastes were introduced with economic benefits, and an integrated system was proposed including energy flow. The system consisted of anaerobic digestion or microbial fuel cell, struvite precipitation for P recovery, nitrogen enrichment by mechanical vapor compression distillation, and incineration processes (optional). Consequently, the energy output from the system could be sufficient for operating the entire system without the need for extra energy input. 相似文献
999.
Junya Yano Takanori Muroi Shin-ichi Sakai 《Journal of Material Cycles and Waste Management》2016,18(4):655-664
Increasing attention is currently given to the management of end-of-life (EoL) hybrid electric vehicles (HEVs), because approximately two decades have passed since they were first introduced to the market. A HEV would be one of the largest consumers of rare earth elements (REEs), and hence represents the greatest potential for REE recovery in the future. The purpose of this study is to clarify the present and future recovery potential of REEs that are disposed of as EoL HEVs. This study first estimated the numbers of EoL HEVs during fiscal years (FYs) 2010–2030, and then clarified the potential for recovery of REEs from two HEV-specific components—the hybrid transmission and NiMH battery unit. The results suggest that 0.51–0.65 million HEVs will reach the EoL stage in FY2030, compared with only 11,000 HEVs in FY2010. As of FY2030, REE recovery potentials will increase to 220 tons and 2900 tons for EoL hybrid transmission and NiMH battery units, respectively. A total of 49,000 tons of REEs will be contained within HEV-specific components of HEVs still in use. Moreover, the potential for recovery of REEs from EoL hybrid transmissions and NiMH battery units is estimated to equal 35.4 and 92.1 % of respective demand. 相似文献
1000.
于2010年12月以及2011年6月采集了大亚湾9个站点的表层水样,利用PCR-变性梯度凝胶电泳(PCR-DGGE)技术对浮游细菌DNA指纹进行了分析.结果显示,大亚湾海域浮游细菌DNA指纹比较丰富,冬季和夏季样品中分别共得到32条和33条条带,每个样品得到的条带数为18~25条.DNA指纹的Shannon-Weaver多样性指数(H')和Pielou均匀度(J)的变化范围分别为2.48~2.88和0.80~0.93.DNA指纹条带数与温度和盐度明显正相关,而与p H、DO、透明度呈明显负相关关系.结果说明PCR-DGGE技术可以在一定程度上反映细菌的群落结构和多样性,但需要与其他技术相结合方能较全面反映细菌的结构与功能. 相似文献