Advanced Materials Research Vols. 512-515

Abstract: This paper gives the description of the scheme of solar energy lighting system. In the stated scheme, constant voltage tracking technology is used to complete the solar battery charging. The intelligent charging technology is used to implement over-current protection, over-voltage protection, and over-temperature protection.

Abstract: This article describes the solar hot water system, and establishes the computational model of hot water system. It analyzes the economical efficiency of solar water heaters which equipped with electric water heaters, gas water heaters and air-source heat pump water heaters. The results show that the initial investment of the system which equipped with an electric water heater and a gas water heater is almost, but the operating cost which equipped with a gas water heater system is lower. The operating cost which equipped with an air-source heat pump water heater is the lowest, though the initial investment is the highest. The solar hot water system which equipped with an air-source heat pump water heater has important reference value for going low-carbon economy road in China.

Abstract: Our country building energy consumption is amazing, building ventilation energy consumption is about more than 20% of the whole energy consumption , its energy saving potential is very great, How to reduce ventilation energy consumption and still keep good indoor air quality, makes the indoor natural ventilation ways becoming the focus of attention. This paper studies the solar chimney，one of ways of solar strengthening natural ventilation，strengthening natural ventilation；At the same time use FLUENT software simulate solar chimney model，Analysis the calculated results, get a reasonable solar chimney thickness and the air flow to meet the indoor ventilated requirements, so as to provide theoretical basis for the practical application.

Abstract: Combined solar thermal and electric system is a combination of solar thermal system and solar electric system, such that both electric power and hot water can be produced at the same time. The solar collecting system includes a concentrator, frames, and a solar tracking system. The hot water system includes a flat collector, flow channels, water tubes, a storage tank, and a water pump. The power generation system is composed of thermoelectric modules and the associated controller. A miniature system was established and its performance was tested in this study. It was found that at the solar radiation flux of 800 W/m2, a total efficiency of 50% could be achieved. However, most of the solar energy has been converted to thermal energy instead of electricity. Our thermal electric system’s total efficiency can reach 43% and power generation of thermoelectric modules is only 0.6%.

Abstract: The Palos Verdes (P-V) modified model for gas generation rate was given, to resolve the supposition for critical point of the gas generation peak in the P-V model. The laboratory experiments of biolysis reaction with typical ratio of waste component (the organic fraction of readily degradation is 55%, 30%, and 15%, respectively) were conducted. At the first stage, the reaction coefficient k1 was equal to 0.01512, 0.00792 and 0.00756day-1, and the reaction coefficient k2 was equal to 0.0317, 0.0181 and 0.0145day-1, respectively ,at the second stage. And the initial production potential was equal to 5900, 2800, and 486 m3 /ton, respectively. The gas generation in the first stage was effected obviously by the waste component. The gas generation occurred in the first stage must be considered to evaluate the landfill gas production. Moreover, the reliability and practicability of the P-V modified model was approved by the better fitting from the simulation result and the testing data of the gas generation rate.

Abstract: Nowadays, the utilization of the by-product glycerol has become a common problem with the large amount of biodiesel production. This paper studied the conversion of the by-product glycerol of biodiesel production by Klebsiella pneumonia to 1,3-propanediol. The crude glycerol could be used directly without refining by a lactate dehydrogenase deficient K. pneumoniae and the lactic acid concentration was very low. In the fed-batch fermentation of 7L fermenter, 93.3g/l 1,3-propanediol was obtained and lactic acid concentration was just 2g/l. Analysis showed that D-type lactic acid synthesis was reduced obviously. The fermentation also was scaled up on the 42L fermenter. 1,3-propanediol and 2,3-Butanediol concentration reached 81.5g/l and 33.8g/l, respectively. No lactic acid was detected. The demonstration fermentation in 5000L fermenter was also successfully performed. The final 1,3-propanediol concentration and productivity was 87g/l and 1.2g/(lh). This work was considered useful to the integrated production of biodiesel and 1,3-propanediol.

Abstract: Heterogeneous catalysts not only can provide as much reactive activity as homogeneous catalysts but they are very much more environmentally benign.This paper introduced a two-step catalyzed process for biodiesel production from low-quality feedstocks, then emphatically reviewed various heterogeneous acid catalysts for pre-esterification and base catalysts for transesterification during this process.

Abstract: The anaerobic fermentation characteristics of green and dried corn straw pretreated by steam explosion method were investigated. The steam pressure and retention time were 1.0Mpa and 90s, TS of fermentation liquid were 2% and 4%. It was shown that the fermentation cycle of green straw is shorter than that of the dried one by 4-7 days, the gas productivity of green straw is 220 mL/gVS, which is higher than that of dried one (153 mL/gVS) while TS is 2%, but there is no significant difference between the green and dried corn straw while TS is 4%, the average methane content in biogas produced from green straw is slightly less than that of the dried one.

Abstract: In the preparation of hydrogen, the bio-oil from pyrolysis of biomass must be further upgraded (catalytic steam reforming)SO as to improve its quality．However the catalyst used in the steam reforming reaction is easy to lose its activity due to being coked' SO that it is important to study the coke formation and its efects on the catalyst activity in the steam reforming process．Fourier Transform Infrared Spectroscopy were used to analyze the precursor of coke on the catalyst Ni/MgO-La₂O₃-Al₂O₃ used in steam reforming reaction and the mechanism of coking Was also discussed based on it．The results indicate that precursors of coke deposited inside the pore of the molecular sieve are mainly paraffin, alcohols, aldehydes and ketones, and aromatic compounds.

Abstract: As the effective and efficient means of resources utilization, biomass energy has become a very valuable and reliable source of alternative energy in China, especially for remote areas and countryside. First, in order to facilitate the development of biogas applications and promote the economic, social and ecological benefits from comprehensive utilization of biogas in rural areas in Urumqi (Capital of Xinjiang Uygur Autonomous Region, XUAR), the biogas potential was estimated, the biogas engineering construction and biogas comprehensive utilization were evaluated, and the existing problems of biogas development were analyzed, in this study. Second, countermeasures and recommendations were proposed in trying to resolved existing problems, based on international practical experience. And, according to local climatic situation and regional characteristics in Urumqi, ecological agriculture was proposed in this study as the development mode for the rural areas in Urumqi, based on the development of biogas technologies and international practical experience.