氧弹燃烧法测定固体的分解焓

以碳酸钡分解焓测定为例,探讨了用氧弹热量计测定固体分解焓的方法,建立了固体分解焓氧弹法测定技术。准确称取一定量的测试样品和基准物质,均匀混合后压片,放入氧弹中充入高压纯氧,然后将测试样品在氧弹中完全灰化,并记录燃烧前后时间与量热计温度变化数据,将测试数据用自编的氧弹燃烧法数据处理系统进行分析。结果表明,用氧弹燃烧法测定固体的分解焓是可行和可靠的,对进一步拓展用氧弹法测定煤炭、污泥、饲料、建筑材料等材质的热值具有参考价值。     

Overall Kinetics of Heat Treatment of Municipal Solid Waste

A mathematical model of the overall kinetics of heat treatment of municipal solid waste was developed. The model considers the main initial substances and products of the reaction of municipal solid waste treatment at high temperatures (1300–1500°C) in a tubular flow reactor.     

Energy Recovery from Municipal Solid Waste in Small Communities

The heating values of municipal solid waste generated in three towns with a population of less than 50 000, situated in Galicia (Spain), were measured with a static bomb calorimeter. Samples of raw refuse were burnt either as received or after sorting of the different combustible components. A study was made of samples from controlled and uncontrolled landfills. The calorific values were compared with those corresponding to a commercial residual derived fuel in order to study the possibility of using municipal solid waste as a source of recovered energy. This revised version was published online in July 2006 with corrections to the Cover Date.     

Plasma-Assisted Treatment of Municipal Solid Waste: A Scenario Analysis

Small-scale thermal treatment of municipal solid waste (MSW) was investigated using mass and energy balances based on the assumption of thermodynamic equilibrium. A typical average MSW composition from the literature was used as basis for modelling of a one ton per day waste gasification facility (plant). Syngas production by pyrolysis, stoichiometric O₂ addition and auto-thermal (gasification with oxygen and/or air where no external heat input is required) combustion were considered. These cases were evaluated for production of electricity only, and steam. From purely thermodynamic considerations, it was observed that auto-thermal oxygen gasification produces the most electricity (47.00 kWe) and oxygen plasma gasification produces a positive net amount (4.07 kWe) on a 1 ton per day scale. Although auto-thermal air gasification also produces a net positive amount, the calorific value of the syngas is too low to fuel an internal combustion engine. As expected, the amount of steam generated by the different scenarios is high due to higher process efficiencies. The close-coupled auto-thermal oxygen process proved to be the most efficient. The cost of additional oxygen generation was however not taken into account, and may change the picture significantly.     

Ethanol Production from the Organic Fraction Obtained After Thermal Pretreatment of Municipal Solid Waste

In this work, the use of organic fraction from municipal solid waste (MSW) as substrate for ethanol production based on enzymatic hydrolysis was evaluated. MSW was subjected to a thermal pretreatment (active hygienization) at 160?°C from 5 to 50 min. The organic fiber obtained after 30 min was used as substrate in a simultaneous saccharification and fermentation (SSF) and fed-batch SSF process using cellulases and amylases. In a fed-batch mode with 25% (w/w) substrate loading, final ethanol concentration of 30 g/L was achieved (60% of theoretical). In these conditions, more than 160 L of ethanol per ton of dry matter could be produced from the organic fraction of MSW.     

用铝粉与生活垃圾焚烧底灰制备复合材料的试验研究

以生活垃圾焚烧底灰为增强相,用液相烧结粉末冶金方法,对制备废旧金属铝/生活垃圾焚烧底灰复合材料进行了试验研究.结果表明:当废旧金属铝与生活垃圾焚烧底灰配比为8:2,烧结温度为900℃,保温时间为1.5h,在纯N2保护性气氛的条件下制得的复合材料具有良好的机械性能.如热膨胀系数为0.3×10-6,密度为2.43g/cm3,弹性模量为3014.3Mpa,耐磨性能比铝镁合金的提高了1.3倍.     

Municipal Solid Waste Landfill Leachate Treatment and Electricity Production Using Microbial Fuel Cells

Microbial fuel cells were designed and operated to treat landfill leachate while simultaneously producing electricity. Two designs were tested in batch cycles using landfill leachate as a substrate without inoculation (908 to 3,200 mg/L chemical oxygen demand (COD)): Circle (934 mL) and large-scale microbial fuel cells (MFC) (18.3 L). A total of seven cycles were completed for the Circle MFC and two cycles for the larger-scale MFC. Maximum power densities of 24 to 31 mW/m² (653 to 824 mW/m³) were achieved using the Circle MFC, and a maximum voltage of 635 mV was produced using the larger-scale MFC. In the Circle MFC, COD, biological oxygen demand (BOD), total organic carbon (TOC), and ammonia were removed at an average of 16%, 62%, 23%, and 20%, respectively. The larger-scale MFC achieved an average of 74% BOD removal, 27% TOC removal, and 25% ammonia reduction while operating over 52 days. Analysis of the microbial characteristics of the leachate indicates that there might be both supportive and inhibiting bacteria in landfill leachate for operation of an MFC. Issues related to scale-up and heterogeneity of a mixed substrate remain.     

Elemental uptake of radish grown near a Municipal Solid Waste dumping site by EDXRF

Radish plant was collected along with root and soil from the nearby area of a Municipal Solid Waste dumping site of the metropolitan city of Kolkata, West Bengal, India and analyzed for a wide range of elements using the EDXRF technique with a ¹⁰⁹Cd point source and a Si(Li) detector. The samples comprized of the root-soil, root and leaves. For quality control purposes, NIST standard reference material (SRM) 1648 Urban Particulate Matter had also been analyzed using the same procedure as for the samples. Concentrations of elements with X-ray energies in the range of 3–20 keV in the soil around the root and their uptake pattern by the root and the leaves have been estimated.     

X射线荧光光谱法测定垃圾焚烧炉渣中主要成分

使用X射线荧光光谱仪,采用粉末直接压片制样,以研磨的方式克服粉末样品的粒度效应,理论α系数法校正基体效应,建立了垃圾焚烧炉渣样品中SiO2、Fe2O3、MgO、Al2O3、CaO、K2O、TiO2、P2O5八组分的分析方法.用标准化法进行强度漂移校正,用内控标样制做校准曲线,测定结果的精密度和准确度可以满足日常分析要求.     

Influence of a Municipal Solid Waste Landfill on the Soil Levels of Heavy Metals at Adjacent Territories

Russian Journal of General Chemistry - The levels of heavy metals (Cr, Cu, Zn, Ni, Pb) in the soils of the areas adjacent to the Sharra municipal solid waste landfill located about 7 km...     

An Insight into the Anaerobic Co-digestion of Municipal Solid Waste and Food Waste: Influence of Co-substrate Mixture Ratio and Substrate to Inoculum Ratio on Biogas Production

Applied Biochemistry and Biotechnology - The unbalanced nutrients of municipal solid waste (MSW), particularly high carbon contents, were regarded as a major limiting factor to anaerobic digestion...     

Combustion Rate of Solid Fuels in the Superadiabatic Mode

Theoretical and experimental dependences of the combustion front propagation velocity in a layer of a solid carbon fuel on various external factors and conditions were examined in the case of filtration of the gaseous oxidizing agent. Particular attention was given to the superadiabatic modes with heat accumulation. It was shown that, in the case of a superadiabatic filtration combustion mode, the combustion velocity is primarily determined by the supply rate of the oxidizing agent and by the stoichiometric process ratio for particular conditions.     

Cu—La和Pd—Sn二元合金混合焓的预测

采用Miedema模型对Cu-La和Pd-Sn二元合金混合焓进行了预测。预测结果与文献中的试验数据吻合良好,进一步证明了采用Miedema模型预测二元合金混合焓的适用性。     

Gasification of Powdered Solid Fuel in the Filtration Combustion Mode

A new procedure for gasification of powdered solid fuel in a flow of a gaseous oxidant in the course of filtration of the mixture through an inert packing was suggested and tested. This procedure allows the productive capacity of a single reactor to be increased owing to acceleration of the reactions, i.e., to an increase in the reaction surface area with a decrease in the fuel particle size. As shown in cold (without ignition) experiments, the powdered fuel was partially accumulated in the inert porous packing, which led to the pressure buildup in the reactor. In gasification experiments with ignition, the powdered fuel was not accumulated in the reactor if the temperature in the fuel feeding zone was no less than 500°С. In this case, the linear velocity of the gas increased owing to thermal expansion, and this velocity was sufficient for the coal particles fed to the reactor to be entrained by the flow.     

Combustion of Waste Waters Containing Organic Alkaline Salts

Abstract

The biological treatment of waste waters from chemical industry containing organic and inorganic salts causes problems because these materials inhibit the metabolic activity of the bacteria. One possible and economically feasible way to convert the organic materials into less toxic forms is a thermal oxidation process, which can take place either in a fluidized bed combustor or in a vertical combustion chamber.

The process is described and parameters of the process are discussed. Results from particle measurements on a vertical combustion chamber for the combustion of various artificial waste waters are presented. The chemical analysis of the particulate matter from different stages of the process allows a detailed characterization of the decomposition of the organic material. Conclusions are drawn both with respect to the process and the environment.     

Gasification of Municipal Solid Wastes in Plasma Arc Medium

Many thermal processes have been developed in order to eliminate the municipal solid wastes or produce energy from them. These processes include a wide range of applications from the simplest burning system to plasma gasification. Plasma gasification is based on re-forming of molecules after all molecules convert to smaller molecules or atoms at high temperatures. In this work, the production of fuel gas is aimed by plasma gasification of municipal solid wastes in high temperatures. Because of this, a plasma reactor of the capacity of 10 kg h^?1 was designed which can gasify municipal solid wastes. Plasma gasification with and without steam and oxygen was performed in temperatures of 600, 800, 1000, 1200, 1400 and 1600 °C in the reactor. A gas mixture containing methane, ethane, hydrogen, carbon dioxide and monoxide, whose content varies with temperature, was obtained. It was found that plasma gasification (or plasma pyrolysis, PG), plasma gasification with oxygen (PGO) and plasma gasification with steam (PGS) were more prone to CO formation. A gas product which was consisted of 95% CO between 1200 and 1400 °C was produced. It was observed that a gas with high energy capacity may be produced by feeding oxygen and steam into the entrance of the high temperature region of the reactor.

     

HRGC-LRMS测定垃圾焚烧炉布袋飞灰中的二噁英类物质

利用高分辨气相色谱-低分辨质谱(HRGC-LRMS)测定了某垃圾焚烧厂布袋飞灰中的二(口恶)英类物质,结果表明对于测定二(口恶)英类浓度相对较高的垃圾飞灰而言,采用HRGC-LRMS是一种可行的方法,回收率在74％～114％之间。该飞灰样品中以二(口恶)英为主,呋喃的含量相对较低,二(口恶)英／呋喃值为4.6,二(口恶)英类物质总量为211.7ng／g,折算到毒性当量为0.69ngI-TEQ／g。     

Determination of Organochlorine Pesticides and Polychlorinated Biphenyls Residues in Municipal Solid Waste Compost by Gas Chromatography with Electron−Capture Detection

A simple and efficient method for the simultaneous gas chromatographic determination of ten organochlorine pesticides (α-HCH, β-HCH, γ-HCH, p,p’-DDT, o,p’-DDT, p,p’-DDD, p,p’-DDE, aldrin, endrin, and dieldrin) and six congeners of PCBs (PCB 28, 52, 118, 138, 153, and 180) in municipal solid waste compost is described. The procedure involves a solid-phase dispersion matrix using celite as dispersant sorbent, alumina as clean up sorbent and hexane-dichloromethane (7:3, v/v) mixture as eluting solvent. An additional purification step with copper was necessary to eliminate sulphur. Analysis of the sample was performed by GC-ECD. The method was validated with fortified samples at two concentration levels (0.025 and 0.05 mg kg^?1). Average recovery ranged from 77 to 121% with relative standard deviation between 1 and 18%. The detection limits, which ranged from 0.003 to 0.01 mg kg^?1, were lower than those established by the Baden–Württemberg directive (0.033 mg kg^?1).     

量子化学的Gaussian－2理论及其应用与化合物的标准生成焓预测

本文较为全面地综述了Ｇａｕｓｓｉａｎ－１，Ｇａｕｓｓｉａｎ－２（简称Ｇ１，Ｇ２）理论以及简化的Ｇ２（ＭＰ２），Ｇ２（ＭＰ３）理论，将其主要结果进行了比较分析。关于Ｇ２理论的应用，除了较为详细地综述了几年来理论在重现实验数据、评价实验数据、预测实验数据及研究化学反应途径等方面的应用外，还结合我们近期研究结果的主要结论讨论了该理论在研究等电子－等自旋，价层等电－等旋，等旋及非等旋化学反应的能量计算中的应用情况，以及该理论在预测化合物的标准生成焓方面的应用情况。     

Effect of the Pyrolysis Step on the Filtration Combustion of Solid Organic Fuels

Russian Journal of Applied Chemistry - The results of filtration combustion of various types of wood and wood charcoal are compared. Data on the temperature and composition of the gas in...