Advanced Materials Research Vols. 805-806

Abstract: The influence of heating rate on pyrolysis characteristic and the products evolution performance of sorghum straw, maize straw and cotton straw had been investigated by thermogravimetric analyzer coupled with Fourier transform infrared spectrometry (TG-FTIR), and distributed activation energy model (DAEM) was employed to calculate the kinetic parameters. The results show that with the increasing heating rate, the initial pyrolysis temperature and the maximum weight loss temperature shift to high temperature zone, the maximum weight loss rate increases, and the pyrolysis peak of hemicellulose starts to appear. The pyrolysis characteristic parameters of three crop straws were different because of their physical, chemical characteristics and structure characteristics. The activation energy E of sorghum straw, maize straw and cotton straw is 150~223kJ/mol, 141~217kJ/mol and 155~242kJ/mol, while the corresponding pre-exponent factor distributes between 10¹³and 10¹⁹ s^-1, between 10¹³ and 10¹⁷ s^-1, and between 10¹⁴ and 10²⁰ s^-1,respectively. The main pyrolysis products of three crop straws are H₂O, CO₂, CO, CH₄, formic acid and phenol. The research provides certain theoretical reference for energy regeneration utilization of straw biomass.

Abstract: Thermogravimetric analysis (TGA) was employed to study the pyrolysis characteristics of four glucose-based and three fructose-based carbohydrates. Kinetic parameters were calculated based on the experiment data. The results indicated that the starting and maximal pyrolysis temperatures of the glucose-based carbohydrates were increased steadily as the rising of their degree of polymerization (DP). The fructose-based carbohydrates exhibited similar pyrolysis behaviors as the glucose-based carbohydrates, but the difference was smaller. Kinetic calculations revealed that the activation energy values of the glucose-based carbohydrates were higher than those of the fructose-based carbohydrates, indicating the glucose-based carbohydrates were more difficult to decompose than the fructose-based carbohydrates.

Abstract: The biomass replaces the petroleum as energy is involved in energy transformations. There are two grade transformations from the wheat which are the fuel ethanol and the marsh gas ferment. The study on their transformation mechanisms and how to improve their energy efficiency will be benefit for both the academic and practical significance. Studies have shown that at least 67.05% wheat energy changes into fuel ethanol and at least 15.46% the rest of accessory substance alcohol lees energy changes into marsh gas. The total energy transformation amount is not less than 82.51%.The ratio of the wheat fuel ethanol input to output is 1.04, and NEV is 1167 MJ. The result shows the values of energy gain are positive.

Abstract: In this work, a promising method for production of high value-added aromatic aldehydes from lignin was proposed. The concept is based on the use of metalloporphyin as catalyst and hydrogen peroxide as oxidant under alkaline condition. The biomimetic catalyst Co (TPPS₄) (TPPS₄=meso-tetra (p-sulphonatophenyl) porphyrin) was prepared and characterized by ¹H-NMR spectroscopy, FT-IR spectroscopy and UVvisible spectroscopy. It exhibited high activity in the catalytic oxidation of lignin. The main products were p-hydroxybenzaldehyde, vanillin, and syringaldehyde from catalytic oxidation of lignin, which in total were up to 75.09% of the identified compounds by GC-MS. The yield of the three aromatic aldehydes was 12.84 wt.%, compared to a poor 2.63 wt.% yield of the three aromatic aldehydes without Co (TPPS₄).

Abstract: Twenty three strains of oleaginous fungus were screened out from the excess sludge by Sudan black B staining method. After 26s rDNA sequence analysis and comparison, 10 of the strains were found to be Pichia jadini, 9 to be Trichosporon laibachii, and the other 4 to be Galactomyces geotrichum, which belong to molds. We focused on 7 strains of Tri. laibachii, and measured their biomass and oil yield. As a result, Tri. laibachii IEM-17 had the highest biomass, as well as the highest oil yield which reached 21.9%.

Abstract: Bioconversion of potato pulp to fuel ethanol, analysing the potato pulp chemical composition and determining the potato pulp in the role of microorganism produce ethanol under the best conditions is the major research. An analysis of the chemical composition of potato pulp showed that : the basic ingredients are Protein (9.72%), Starch (25.52%), Cellulose (17.90%). The effects of ethanol production rate of solid-liquid ratio, fermentation temperature, inoculumconcertration, fermentation time. The results showed that: the best conditions producting ethanol from potato pulp obtained by single factor experiments are: solid-liquid ratio: 1:15, fermentation temperature: 35°C, inoculumconcertration: 3mL, fermentation time: 20h. Under this occasion, the ethanol production rate was 0.183mL·g^-1.

Abstract: China is a big agricultural country, which had many kinds of biomass resources. Biomass energy belongs to clean energy, it was available to achieve zero co₂ emissions and substitute fossil fuels such as coal, oil and gas to be an important energy. Through the transformation of 35t/h coal-fired CFB boiler, which based on material and circulated carrier, burning biological energy, changed boiler from consuming one-time energy to the regenerative energy, which saved coal and prevented waste from directly emitting into the atmosphere to pollute the environment. It would save energy and increase the local farmers additional income by sell stem, which followed the trend of the national development strategy. The test data show that: this transformation of boiler is very successful, indicate that we can transform some original polluted boiler which consume coal to some degree and provide some experimental methods for these transformations.

Abstract: In order to give full play to PV/Wind hybrid system, a mathematic model of optimization design considering power supply reliability is proposed in this paper. Firstly, the structure of PV/Wind hybrid system is given, so are the mathematical models of wind generators, PV modulesand batteries are. Then,the mathematic model of optimization design is determined: in the case of meeting the power supply reliability, an objective function is constructed to minimize the total costs of system investment costs, operation and maintenance costs and system power loss cost, which are limited by realistic constraints. Finally, an PV/Wind hybrid system is employed to validate the model, results show that the mathematic model proposed in this paper is suitable to design a PV/Wind hybrid system.

Abstract: The performance experiments have been carried out by using the spiral Savonius wind rotor of which rotor has 2 blades, rotor diameter is D=420mm, rotor height is H=680mm and gap distance e =100mm. The static torque values at low wind speed and the power of the rotor have been measured. Experimental results show that the static toque values at different azimuths are almost constant and the maximum power coefficient can reach 0.113 at the tip speed ratio of λ= 0.49.

Abstract: The structure of the wind turbine generator system is complex and it is difficult to identify the fault signals because of fault frequency aliasing on the vibration characteristics. The wind turbine fault diagnosis method is raised on single component shock to solve the vibration signal feature extraction during the wind turbines operating. Based on the principle of Hilbert envelope demodulation, this envelope demodulation method is presented for the single IMF component which contains shock fault characteristic frequency to solve the possible problem which fault Frequency is difficult to identify when the original signal is directly asked to envelope. This method has been applied and verified when a wind farm CSC-855W wind turbine vibration monitoring device was presented. The results show that compared with the traditional envelope demodulation method, by this method wind turbine fault characteristic can be more effectively and directly extracted and the accuracy of fault diagnosis can be improved. It is of great practical value.