Wen Yan Li

Steam Gasification of Biomass Coupled with Lime-Based CO2 Capture in a Dual Fluidized Bed: A Modeling Study

Biomass is an important renewable energy and making hydrogen-rich syngas from biomass is promising. Dual fluidized bed gasification technology can increase hydrogen content in the syngas. Moreover, steam gasification of biomass coupled with lime-based CO2 capture in a dual fluidized bed can further improve the syngas quality . This paper established a dual fluidized bed gasification model using Aspen plus,in order to explore the effect of different gasification temperatures and steam to biomass ratios on hydrogen content in syngas, providing a theoretical basis for the optimization of operating parameters and process.

Density Functional Theory Study of Interaction between CO and Oxygen Carrier Fe2O3@SBA-15

Fe2O3@SBA-15 oxygen carrier models were built to investigate the reaction stoichiometry mechanism between the fuel gas CO and oxygen carrier Fe2O3 in chemical-looping combustion system. The binding energy of CO adsorption on Fe2O3@ SBA-15 is -0.402 eV, and the atomic structures, electronic proper of the CO/Fe2O3@SBA were also analyzed. The calculation results for the oxidation CO have an important understanding of the process of scientific significance, which will promote the fundamental understanding and applications of the oxygen carrier Fe2O3.

Overview of Chemical Characterization of Biomass Fast Pyrolysis Oils

Fast pyrolysis of biomass to produce bio-oil is one of the most promising technologies to utilize lignocellulosic biomass. Liquid bio-oil covers many potential application fields, to be used a fuel or a source for chemical extraction and production. Hence, it is necessary to understand the chemical properties of bio-oil. This review concentrates on the elemental and chemical properties of bio-oil, and also discusses the analysis and separation methods.

The Application and Development of IGCC Power Generation Technology in China

With the serious problems caused by environment distruction, the large attention was taken to environmental protection. The coal pollution as one of the critical problems isurgently need to solve. Integrated Gasification Combined Cycle (IGCC), an advanced clean coal power generation system, is a main hotspot in energy and power field all over the world. This paper mainly focuses on the technology, development trend and the problems of IGCC in Tianjin. The success of IGCC greatly enhances the international influence of our country in dealing with the global climate change,which also makes great significance in the development and storage of Chinas coal-fired power generation.

The Numerical Simulation Analysis of the Power Station Boiler Heating Surface Slagging

Slagging is a very complicated physical and chemical process which refers to several scientific cores such as combustion, multiphase flow, heat and mass transfer etc. This paper is to build a mathematical modeling of fuzzy comprehensive judgment and to predicate the distribution of slagging on the heated surface by utilizing the theory of fuzzy mathematics. Then a prediction is made in the boiler of Tuoketuo power plant from Datang Corporation with this method, the results are better consistent with the actual conditions.

Thermogravimetric Analysis of Raw and Demineralized Biomass Materials

Thermogravimetric analysis (TGA) was employed to study the pyrolysis characteristics of two biomass materials (poplar and pine wood) and their demineralized samples under nitrogen atmosphere. Based on the experimental results, the pyrolysis kinetics were calculated. The results indicated that the starting and ending time of devolatilization were delayed after the demineralization of the biomass. For all the materials, the temperature of the maximum weight loss rate occurred at around 390°C, while the maximum values increased a little after demineralization. The pine wood was more difficult to decompose than the poplar wood, due to its high activation energy values. In addition, after demineralization, the activation energy values of the pine wood decreased, while the values of the poplar wood were not significantly changed.

The Sintering Characteristics of Industrial Solid Waste Incinerator

Burning the industrial solid waste can form low melting point alkali salts to cause heavy sinters in the incinerator. The utilization of additives is proved to be effective to reduce the sintering in this work. Three additives (lime, kaolin and coal ash of an electric power plant) were mixed in different proportions with the industrial solid waste, and then an ash fusibility test was performed on the solid waste and the mixtures. The results show that, the solid waste exhibits a low melting point and the chemical additives can increase it efficiently. Furthermore, the anti-sintering mechanisms may conclude that the additives react with the alkali salts in the solid waste to form the high melting point materials.

Potassium Solubility of the Fly Ash from Corn Straw Power Plant

The industry of biomass power in China has been growing tremendously in recent years, but it is faced with many challenges now. The low efficiency of straw combustion in the boiler results in that the carbon content in the fly ash could reach 15~30%. The ash is also rich in silica, potassium, calcium and has a lot of microelements. A kind of fly ash from a biomass power plant mainly uses corn straw as feedstock was studied. XRF analysis showed that the contents of K2O, CaO and MgO in the ash were 7.22%, 13.61% and 7.22%, respectively. Leaching experiments were conducted to evaluate the solubility of nutritive elements K, Ca and Mg in the ash. The results indicated that acid could enhance the solubility compared with pure water. Under the optimal conditions of filtrate final pH neutral, leaching time 20min, ratio of liquid to solid (L/S) 2, reaction temperature 40°C and stirring time 1min just for homogenization, 36.9% of K, 42.8% of Ca and 10.1% of Mg in the ash could be extracted. These dissolution rates were still very low, that means, the thorough extraction is not very easy and further research should be continued to make the straw power industry ecological and sustainable.

Production and Characterization of Rice Husk Chars Obtained under Different Conditions

Rice husk was subjected to slow and fast pyrolysis under different reaction conditions, to investigate the effects of several pyrolysis factors on the physicochemical properties of the rice husk chars, including the pyrolysis heating rate, cooling rate and resident time. The results indicated that the char yield did not show great changes during the slow pyrolysis process, while it was gradually decreased along with the resident time during the fast pyrolysis process. With the elevating of the pyrolysis conditions, the carbon content of the chars was increased monotonically, while the oxygen content was decreased. Moreover, the rice husk and its chars greatly differed in their functional groups, resulting from various decompositon, decarbonylation and aromatization reactions during the pyrolysis process.

One Based Magnetic Oxygen Carrier Solid Fuel Chemical Looping Combustion System Simulation

In this paper, Computational Fluid Dynamics (CFD) was used to simulate the magnetic device for the separation of Fe-base oxygen carrier in chemical-looping combustion system. The simulation was based on the Euler multiphase flow model and the k-ε turbulence model, which uses UDF programming to increase volume source phase. Here, commercial computational fluid dynamics software fluent platform was used to build the air reactor cold flow mathematical model, magnetic field under the conditions of different flow conditions were added for separating the Fe3O4 and Fe2O3. And the simulation results has an important understanding of the process of scientific significance, and will promote the fundamental understanding and applications of the Fe-base oxygen carrier.