Advanced Materials Research Vols. 1008-1009

Abstract: In this paper, through the study of reducing sugar conditions of corn straw hydrolysis under acidic condition, looking for the production of experimental conditions relatively reasonable. Mainly by dilute sulfuric acid hydrolysis of corn straw by single factor test, effects of sulfuric acid concentration, temperature, reaction time, particle size, ratio of solid to liquid five factors, effects on sugar yield of corn straw. The dilute sulfuric acid concentration 5%, ratio of solid to liquid was 1:14, when the reaction time is 140 min, particle fineness of 120 mesh, the reaction temperature is 100 °C, corn stalk sugar yield reached a maximum 20.11%.

Abstract: The process of biodiesel made from waste cooking oil via acid catalyst was studied in order to eliminate the waste cooking oil pollution and realize the health of waste oil use. The optimum conditions of biodiesel made from waste cooking oil, effect of reaction time, alcohol-oil ratio and catalyst dosage to the biodiesel conversion were explored by using orthogonal experiment design. The results showed that the conversion of biodiesel is 95.2% under the conditions of the reaction time is 2h, the alcohol-oil ratio is 6:1, the catalyst dosage is 1.5%, and the influence factors can be arranged as follows: reaction time > catalyst dosage > alcohol-oil ratio.

Abstract: The average temperature is low in cold regions; therefore, under natural conditions, the gas production is more unlikely to be successful. When temperature drops below 6 °C in the biogas digester, it stops producing gas. By aiming household biogas digesters as subjects, from the test materials, experimental methods, experimental test results and economic analysis, this experiment studied the feasibility of heating with biomass energy for biogas digester to accomplish the digesters gas production in winter in in cold regions.

Abstract: Ethanol is a kind of basic biomass liquid energy , the conversion of biomass to ethanol has been studied extensively. The process of biomass pretreatment can change its physical and chemical properties, and these changes affect the chemical conversion of biomass products in quality and yield of late. This paper reviews the physical method, chemical method, biological method, three kinds of pretreatment technique, the related principle and development prospects are introduced.

Abstract: The composition of palm methyl ester (PME) was determined and quantified by Gas chromatography-Mass spectrometer (GC-MS). Cold flow properties of PME was studied by means of cold filter plugging point tester and kinematic viscosity tester and the solution crystallization theory, at the same time to observe the crystalline mechanism with low temperature phase contrast microscope. Experimental results showed that PME was mainly composed of saturated fatty acid methyl ester (SFAME) and unsaturated fatty acid methyl ester (UFAME), PME has a poor cold flow properties because of its more SFAME content. Observation results of the microscope showed that, the crystallization of PME at a steady cooling rate was lamellar crystal for rules. With the reduction of temperature, lamellar crystal increased gradually, and aggregated together. The higher the cooling rate was, the smaller the lamellar crystal and the irregular shape was.

Abstract: Anaerobic digestion of single dairy manure, single vegetable waste, mixture of dairy manure and vegetable waste was conducted to produce biogas. Startup characteristic, leachate parameters and inoculation amount were investigated. The experimental results showed that anaerobic digestion can start up quickly with acclimated thickening sludge as inoculation sludge and 30% was appropriate inoculation percentage. Digestion of single dairy manure and mixture of dairy manure and vegetable waste appeared better buffering ability with higher alkalinity than single vegetable waste. Compared to single digestion of dairy manure or vegetable waste, mixture of dairy manure and vegetable waste is more suitable for anaerobic digestion. Under the conditions of TS=10% and T=(36±1)°C, cumulative biogas production of mixture of dairy manure and vegetable waste is 5281 mL during the period of 30 days and average daily gas production is about 176 mL. These results could provide theoretical data for practical biogas engineering.

Abstract: Biomass energy is a kind of clean renewable energy, and the resources are abundant. With the rapid development in recent years, the biomass power generation has become one of the electric power new energy with the large-scale commercialization development prospects. The industry competitiveness evaluation of biomass power generation in China is the basis to explore the biomass power generation industry development strategy, which also can indicate the direction for the rapid and sound development of biomass power generation industry in China. To evaluate the industry competitiveness of biomass power generation scientifically and accurately, we defined the subordinate function and weight proportion and constructed the multi-level fuzzy comprehensive evaluation (FCE) model. The biomass competitiveness evaluation of biomass power generation showed that the results given by this model are reliable and precise.

Abstract: The analytical hierarchical process (AHP) was adopted in this study to determine the priority of the policy criterion related to promoting wind energy, considering the environmental practitioners’ points of view. The results were described as follows. The practitioners from environmental organizations suggested that the most important major criteria are in the following order: policy criterion layer, technical criterion layer, economy criterion layer, and energy education criterion layer. For the global weights of the criteria, the criteria with top five weights were in the order as follows: “active development of green energy industry by government”, “supply and consumption method of low-carbon and low-pollution energy”, “increase of percentage of power generation from renewable energy in total power supply”, “encourage manufacturers to develop new wind power generation technology”, and “continually develop the technology projects which has potential and prospects in the future”.

Abstract: For power grid with large-scale wind energy, the short-term wind power prediction is important to the grid’s scheduling and stable operating. The overall short-term forecast for wind power connected to the grid relies on the wind velocity and historical power data. Firstly, K-means clustering is introduced to model the power grid, so that the relationship between wind velocity and power can be perfectly described. Considering that there are multiple factors contributing to the prediction of wind velocity and power, we use real data of 15 wind generating set to obtain dependable weight factors of all those dimensions. With the support of mass data, the prediction of power is proved by several measurements (ME, MRE, MAE, RMSE) to be accurate.

Abstract: The turbulence intensity is an important parameter in wind energy resource assessment, and is the main basis of the wind turbine design and equipment shaping. This paper introduces the methods of turbulence intensity calculation, especially the method based on turbulence transport models in CFD. The CFD method of Meteodyn WT is applied to calculate turbulence intensity of wind farm site in complex terrain of some area, and the simulation is compared with measured date by the mast and the simulation based on the line model. The results show that CFD method of Meteodyn WT provides good results of turbulence intensity. It is significant that the CFD method is applied in wind resource assessment and micrositing of wind farm.