Thermal conversion of rice husks and sawdust to liquid fuel

The paper focuses on studying the conversion of rice husks and sawdust into liquid fuel. Rice husks, sawdust and their mixture are pyrolyzed at temperatures between 420 and 540 degrees C, and the main product of liquid fuel is obtained. The experimental result shows that the yield of liquid fuel depends on various factors such as feedstock and temperature. The maximum yields for rice husks, sawdust and their mixture are 56%, 61% and 60% at 465, 490 and 475 degrees C, respectively. Analyses with GC-MS and other apparatus show that the liquid fuel is a complicated compound with low caloric value and can be directly used as a fuel oil for combustion in a boiler or a furnace without any upgrading. Alternatively, the fuel can be refined to be used by vehicles.     

Prediction of higher heating value of solid fuel produced by hydrothermal carbonization of empty fruit bunch and various biomass feedstock

Journal of Material Cycles and Waste Management - There are many influencing variables when it comes to designing a thermal conversion system for biomass and other fuels. One of the most important...     

Treatment of residual lubricating oil using rice husk-based material as ecological adsorbent

Journal of Material Cycles and Waste Management - One of the most significant environmental problems the world population faces is the inadequate disposal of petroleum derivatives. Lubricant oil is...     

Evaluation of carbonization as a thermal pretreatment method for landfilling by column leaching tests

To evaluate carbonization as a thermal pretreatment method for landfilling, the releasing characteristics of organic and inorganic constituents from carbonization residue derived from shredded residue of bulky waste was investigated by means of batch and column leaching tests. Shredded residue of bulky waste itself and its incineration ash were tested together to compare pretreatment methods. In batch leaching tests at a liquid/solid ratio of 10, the release of organic carbon from carbonization residue was at a remarkably low level. Besides, carbonization contributed to immobilize heavy metals such as chromium, cadmium, and lead within its residue. In column tests, the discharges of organic constituents were lowest from carbonization residue under aerobic conditions due to microbial activity. The leaching of Cd, Cr, Pb, and Cu from carbonization residue was suppressed under anaerobic conditions; however, this suppression effect tended to be weaker under aerobic conditions. From the results showing that the total releasing amounts of organic and inorganic constituents from carbonization residue are so low as to be comparable to that of incineration ash, carbonization can be considered as one of the thermal pretreatment methods of organic wastes.     

Thermal conversion of municipal solid waste via hydrothermal carbonization: comparison of carbonization products to products from current waste management techniques

Hydrothermal carbonization (HTC) is a novel thermal conversion process that may be a viable means for managing solid waste streams while minimizing greenhouse gas production and producing residual material with intrinsic value. HTC is a wet, relatively low temperature (180-350 °C) thermal conversion process that has been shown to convert biomass to a carbonaceous residue referred to as hydrochar. Results from batch experiments indicate HTC of representative waste materials is feasible, and results in the majority of carbon (45-75% of the initially present carbon) remaining within the hydrochar. Gas production during the batch experiments suggests that longer reaction periods may be desirable to maximize the production of energy-favorable products. If using the hydrochar for applications in which the carbon will remain stored, results suggest that the gaseous products from HTC result in fewer g CO(2)-equivalent emissions than the gases associated with landfilling, composting, and incineration. When considering the use of hydrochar as a solid fuel, more energy can be derived from the hydrochar than from the gases resulting from waste degradation during landfilling and anaerobic digestion, and from incineration of food waste. Carbon emissions resulting from the use of the hydrochar as a fuel source are smaller than those associated with incineration, suggesting HTC may serve as an environmentally beneficial alternative to incineration. The type and extent of environmental benefits derived from HTC will be dependent on hydrochar use/the purpose for HTC (e.g., energy generation or carbon storage).     

Characterizations of biochar from hydrothermal carbonization of exhausted coffee residue

The aim of this study was to produce renewable energy from exhausted coffee residue, which is a form of biomass. As coffee preference continues to increase, the importation of coffee beans has been increasing sharply. However, the amount of coffee that is actually consumed is only about 0.2% of coffee beans, while the spent coffee beans are discarded in the form of exhausted coffee residue. Hydrothermal carbonization is a method of producing an improved fuel from renewable energy sources by changing the physical and chemical properties of biochars. Biochars were obtained from a variety of reaction temperatures during hydrothermal carbonization and analyzed using elemental analysis, ultimate analysis, and calorific value measurement. The atomic C/O and C/H ratios of all obtained biochars decreased and were found to be similar to those of lignite and sub-bituminous coal. The highest energy recovery efficiency of biochar indicates that the optimum reaction temperature for hydrothermal carbonization was between 210 and 240 °C, which produced biochars with calorific value of approximately 26–27 MJ/kg. The spectra of biochars obtained from Fourier transform infrared spectroscopy (FTIR) showed fewer C–O and aliphatic C–H functional groups, but more carbonyl C=O functional groups and aliphatic CH _x groups. The results of this study indicate that hydrothermal carbonization can be used as an effective means to generate highly energy-efficient renewable fuel resources from coffee residue. The thermogravimetric analysis provided the changing combustion characteristics due to increased fixed carbon content.     

Using liquid waste streams as the moisture source during the hydrothermal carbonization of municipal solid wastes

Hydrothermal carbonization (HTC) is a thermal conversion process that can be an environmentally beneficial approach for the conversion of municipal solid wastes to value-added products. The influence of using activated sludge and landfill leachate as initial moisture sources during the carbonization of paper, food waste and yard waste over time at 250 °C was evaluated. Results from batch experiments indicate that the use of activated sludge and landfill leachate are acceptable alternative supplemental liquid sources, ultimately imparting minimal impact on carbonization product characteristics and yields. Regression results indicate that the initial carbon content of the feedstock is more influential than any of the characteristics of the initial liquid source and is statistically significant when describing the relationship associated with all evaluated carbonization products. Initial liquid-phase characteristics are only statistically significant when describing the solids energy content and the mass of carbon in the gas-phase. The use of these alternative liquid sources has the potential to greatly increase the sustainability of the carbonization process. A life cycle assessment is required to quantify the benefits associated with using these alternative liquid sources.     

福州经济技术开发区产业低碳化转型研究

在构建福州经济技术开发区产业低碳化转型评价指标体系的基础上,运用主成分分析法与标准离差法进行模糊Borda组合评价的综合评价模型,对不同情景进行定量分析,提出福州经济技术开发区产业低碳化转型的重点调整部门和重点发展部门,为福州经济技术开发区的产业低碳化转型提供参考.     

Survey of carbonization facilities for municipal solid waste treatment in Japan

The operations of carbonization facilities for municipal solid waste treatment in Japan were examined. Input waste, system processes, material flows, quality of char and its utilization, fuel and chemical consumption, control of facility emissions, and trouble areas in facility operation were investigated and analyzed. Although carbonization is a technically available thermochemical conversion method for municipal solid waste treatment, problems of energy efficiency and char utilization must be solved for carbonization to be competitive. Possible solutions include (1) optimizing the composition of input waste, treatment scale, organization of unit processes, operational methods, and quality and yield of char on the basis of analysis and feedback of long-term operating data of present operating facilities and (2) securing stable char demands by linking with local industries such as thermal electric power companies, iron manufacturing plants, and cement production plants.     

Effect of mixing ratio of woody waste and food waste on the characteristics of carbonization residue

Biomass such as woody waste and food waste can be converted to a renewable energy source by means of carbonization processes. The basic characteristics of woody waste and food waste, such as proximate analysis and heating value, were evaluated before carrying out carbonization tests. Carbonization tests were carried out to obtain the basic characteristics of carbonization residue on changing the proportion of food waste from 0% to 30% in the mixture of woody waste and food waste. The effect of the food waste was estimated by basic characteristics of the residue such as the heating value, yield, and fuel ratio. As increased the food waste content, the bulk density, yield and chlorine content of the carbonization residue increased, but fuel ratio, the carbon content and heating value of the residue decreased. From the results of the basic characteristics of the residue, the optimum food waste content in carbonization tests was found to be 20%. Even if food waste is combined with woody waste at levels up to 30%, the sulfur and chlorine concentrations in the residue were much lower than the regulatory standard levels. From the results for the fuel ratio and heating value of the residue, the carbonization residue is suitable for use as a renewable energy source and can be categorized by the second grade level of solid fuel products.     

用带式压滤机处理含油污泥

对中油集团锦州石化分公司污水处理场的含油污泥装置进行了改造，介绍了带式压滤机处理含油污泥的机理，特点及工艺流程，从装置近10个 月的运行效果看，生产运行指标，达到了设计要求，同时，带式压滤机处理含油污泥仍具有一些不足之处。     

重金属吸附剂高岭石的改性研究进展

综述了重金属吸附剂高岭石的有机、无机改性方法研究进展,重点介绍了高岭石的无机改性方法(无机酸活化,过渡金属、金属氧化物、无机盐改性)对高岭石结构性质以及吸附性能的改善效果,并与同步改性的蒙脱石进行了比较,针对改性过程中仍然存在的一些不足,结合实际应用的要求,探讨了进一步研究中值得关注的问题.     

Estimation of biogas produced by the landfill of Palermo, applying a Gaussian model

In this work, a procedure is suggested to assess the rate of biogas emitted by the Bellolampo landfill (Palermo, Italy), starting from the data acquired by two of the stations for monitoring meteorological parameters and polluting gases. The data used refer to the period November 2005-July 2006. The methane concentration, measured in the CEP suburb of Palermo, has been analysed together with the meteorological data collected by the station situated inside the landfill area. In the present study, the methane has been chosen as a tracer of the atmospheric pollutants produced by the dump. The data used for assessing the biogas emission refer to night time periods characterized by weak wind blowing from the hill toward the city. The methane rate emitted by the Bellolampo dump has been evaluated using a Gaussian model and considering the landfill both as a single point source and as a multiple point one. The comparison of the results shows that for a first approximation it is sufficient to consider the landfill of Palermo as a single point source. Starting from the monthly percentage composition of the biogas, estimated for the study period, the rate of biogas produced by the dump was evaluated. The total biogas produced by the landfill, obtained as the sum of the emitted component and the recovered one, ranged from 7519.97 to 10,153.7m3/h. For the study period the average monthly estimations of biogas emissions into the atmosphere amount to about 60% of the total biogas produced by the landfill, a little higher than the one estimated by the company responsible for the biogas recovery plant at the landfill.     

柴油低温临界吸收法回收装车挥发油气

研究了采用柴油低温临界吸收法回收装车挥发油气的效果。实验结果表明：按装车挥发油气中的总烃体积分数为20.88%、装车挥发油气流量为280 m³/h、年运行时间为2 668 h计,装置年回收油气量为291 t,装置年最大运行功率为206.770 MW,装置投资回收期为3 a;处理后净化气中的总烃体积分数为1.24%,排放质量浓度低于25 g/m³,油气回收率达95%。处理后净化气满足GB 20950—2007《储油库大气污染物排放标准》,取得了较好的环保效益和经济效益。     

共基质和无机盐对原油降解菌株降解原油效果的影响

从大港油田石油污染土壤中分离筛选出1株原油降解菌X3,对原油的降解率达72．6％,经鉴定X3菌株属于假单胞菌属（Psedomonas）。利用生物摇床对X3菌株降解原油的实验发现,共代谢基质α-乳糖对X3菌株降解原油有促进作用,可使原油降解率提高到80．3％;而葡萄糖和蔗糖对X3菌株降解原油有抑制作用。Fe2＋对X3菌株的降解原油也有促进作用,在α-乳糖和Fe2＋的共同作用下,X3菌株对原油的降解率可达82．3％;K＋和Mg2＋对X3菌株降解原油则有抑制作用。在FeSO4质量浓度为0．2～0．3mg／L时,X3菌株对原油的降解率最高,FeSO4质量浓度继续增加,X3菌株对原油的降解率下降。     

微生物菌剂强化处理油砂

研究了微生物菌剂对油砂的处理效果,并通过第15天和第30天两次追加微生物菌剂和营养物质来加速分解石油类污染物。试验结果表明,经过56d的处理,菌剂强化处理单元最终油去除率达到47．4％;添加营养物质和农家肥的对照单元油去除率为23．6％,证明土著菌种在得到适宜的营养和共代谢基质后降解了部分石油;未做任何处理的原始油砂单元含油量基本没有变化。通过气相色谱一质谱联用分析表明,微生物菌剂对于较少碳原子数的有机物质有较好的降解效果。处理单元中随着石油分解过程的进行,系统pH会有一个明显的下降过程。通过对照单元细菌数的检测发现,改善营养物质和氧含量,可以提高土著菌种的石油降解件能。     

电絮凝法去除SAGD工艺高温采出水中的硅

采用电絮凝法,以新疆油田蒸汽辅助重力泄油(SAGD)工艺高温采出水为研究对象,考察了电流、反应时间、反应温度和初始pH等实际生产中较为可控的工艺条件对电絮凝除硅效果的影响.实验结果表明:在1.0 L的反应器中,反应时间不少于4 min,电流不小于0.8 A,即可达到较好的除硅效果,过大的电流无法提高电絮凝除硅能力;反应...     

微波法稻壳制备活性炭研究

稻壳是稻米加工后产生的大宗农业废弃物,高效、高附加值利用稻壳,对促进循环经济发展具有重要意义。以稻壳为原料,氯化锌为活化剂,采用微波处理,制备出微细孔发达的商业级活性炭。微波法生物质制活性炭,加热时间短,能耗低,是具有商业前景的绿色化学工艺。     

Hydrothermal carbonization of food waste and associated packaging materials for energy source generation

Hydrothermal carbonization (HTC) is a thermal conversion technique that converts food wastes and associated packaging materials to a valuable, energy-rich resource. Food waste collected from local restaurants was carbonized over time at different temperatures (225, 250 and 275 °C) and solids concentrations to determine how process conditions influence carbonization product properties and composition. Experiments were also conducted to determine the influence of packaging material on food waste carbonization. Results indicate the majority of initial carbon remains integrated within the solid-phase at the solids concentrations and reaction temperatures evaluated. Initial solids concentration influences carbon distribution because of increased compound solubilization, while changes in reaction temperature imparted little change on carbon distribution. The presence of packaging materials significantly influences the energy content of the recovered solids. As the proportion of packaging materials increase, the energy content of recovered solids decreases because of the low energetic retention associated with the packaging materials. HTC results in net positive energy balances at all conditions, except at a 5% (dry wt.) solids concentration. Carbonization of food waste and associated packaging materials also results in net positive balances, but energy needs for solids post-processing are significant. Advantages associated with carbonization are not fully realized when only evaluating process energetics. A more detailed life cycle assessment is needed for a more complete comparison of processes.