Conversion of leather wastes to useful products

The main objective of the present study is to investigate the production of useful materials from different kinds of leather waste. Three different types of tannery wastes (chromium- and vegetable-tanned shavings, and buffing dust) were pyrolyzed in a fixed bed reactor at temperatures of 450 and 600 °C under N₂ atmosphere. Gas, oil, ammonium carbonate and carboneous residue were obtained by pyrolysis. The effect of temperature and type of leather waste on product distribution of pyrolysis was investigated. Buffing dust gave the highest yield of oil (ca. 23%), while other wastes recorded yields of ca. 9%. Results of elemental analysis and column chromatography showed that pyrolysis oils could be used as fuel or chemical feedstock after re-treatment. The yields of carboneous residue (chars) were between 37.5% and 48.5% and their calorific value was between 4300 and 6000 kcal kg⁻¹, suitable for use as solid fuel. In addition, these chars were activated by CO₂ to obtain the activated carbon. The activated carbon having highest surface area (799.5 m² g⁻¹) was obtained from chromium-tanned shavings. Activated carbons prepared from chromium-tanned leather were presented as an adsorbant for the adsorption of dyes from aqueous solution.     

矿井竖巷内火灾燃烧模拟实验研究

简要介绍了矿井竖直巷道内火灾燃烧模拟实验系统和所进行的多次火灾模拟实验情况及其结果,研究分析了火灾时期井下几种常见的固体可燃材料（坑木、风筒布、运输胶带,电缆和煤炭等）的火源燃烧过程和特点,以及沿竖直巷道轴向上火灾烟流的温度参数在火源不同燃烧阶段的变化规律。     

Energy recovery from solid waste fuels using advanced gasification technology

Since the mid-1980s, TPS Termiska Processer AB has been working on the development of an atmospheric-pressure gasification process. A major aim at the start of this work was the generation of fuel gas from indigenous fuels to Sweden (i.e. biomass). As the economic climate changed and awareness of the damage to the environment caused by the use of fossil fuels in power generation equipment increased, the aim of the development work at TPS was changed to applying the process to heat and power generation from feedstocks such as biomass and solid wastes. Compared with modern waste incineration with heat recovery, the gasification process will permit an increase in electricity output of up to 50%. The gasification process being developed is based on an atmospheric-pressure circulating fluidised bed gasifier coupled to a tar-cracking vessel. The gas produced from this process is then cooled and cleaned in conventional equipment. The energy-rich gas produced is clean enough to be fired in a gas boiler (and, in the longer term, in an engine or gas turbine) without requiring extensive flue gas cleaning, as is normally required in conventional waste incineration plants. Producing clean fuel gas in this manner, which facilitates the use of efficient gas-fired boilers, means that overall plant electrical efficiencies of close to 30% can be achieved. TPS has performed a considerable amount of pilot plant testing on waste fuels in their gasification/gas cleaning pilot plant in Sweden. Two gasifiers of TPS design have been in operation in Grève-in-Chianti, Italy since 1992. This plant processes 200 tonnes of RDF (refuse-derived fuel) per day. It is planned that the complete TPS gasification process (including the complete fuel gas cleaning system) be demonstrated in several gas turbine-based biomass-fuelled power generating plants in different parts of the world. It is the aim of TPS to prove, at commercial scale, the technical feasibility and economic advantages of the gasification process when it is applied to solid waste fuels. This aim shall be achieved, in the short-term, by employing the cold clean product gas in a gas boiler and, in the longer-term, by firing the gas in engines and gas turbines. A study for a 90 MWth waste-fuelled co-generation plant in Sweden has shown that, already today, gasification of solid waste can compete economically with conventional incineration technologies.     

大空间建筑防排烟系统性能化设计

为了获得合理有效的大空间建筑排烟系统设计方案,从排烟方式的选择、排烟量(排烟面积)的确定以及烟控系统排烟的效果评估和验证三个方面对大空间建筑防排烟系统的性能化设计进行了探讨,并指出:建筑防排烟系统的选择及其排烟量(排烟面积)的确定应结合建筑功能特点、可燃物分布、安全性能目标、补气条件、环境条件等进行综合考虑并进行核算;在条件允许情况下,应尽量采用数值模拟计算、模型试验以及开展实地场所的热烟测试进行防排烟系统的效果验证。本研究结果可为大空间建筑防排烟系统的合理性设计提供参考。     

Mitigation of greenhouse gases by adoption of improved biomass cookstoves

Greenhouse gases especially CO₂ can be reduced with the help of improved biomass cookstoves. This paper deals with the design and development of biomass stoves (single pot and double pot) with better efficiency for meeting household cooking energy requirement. Thermal performance, flue gas emission of carbon monoxide (CO) and carbon dioxide (CO₂) have been investigated. It was seen from the result that the flue gas emission is within permissible limit as recommended by World Health Organization. The design of improved biomass stove sent to Palampur (32^o10’N,76^o30’E) center situated in Himalaya in hilly terrain of India, where the acceptability of double pot stoves (85%) is quite high compared to single pot stoves (30%). Thermal efficiencies of both single and double pot stove were recorded about 21% and 25% respectively. An improved biomass cookstove can save about 161 kg of CO₂ annually. Improved cookstoves was found eco-friendly in nature and suitable for the cooking requirement of hilly areas.     

自吸式文丘里旋流板油烟净化设备研究与开发

文章指出了餐饮业油烟的危害和特性,归纳了餐饮业油烟净化技术分类,介绍了一种集多种湿法除油烟技术之长处于一体的自吸式文丘里旋流板餐饮油烟净化设备,分析了该设备结构尺寸对除油烟效率及系统阻力的影响;采用清水、1%NaOH溶液、Y吸收剂的净化实验表明:油烟专用吸收液Y吸收剂可以明显提高除油烟效率,有效去除油烟异味。     

生物质发电工程的环保设计

简要介绍生物质发电工程环保设计的重点,确保环保达标;并总结工程设计中遇到的常见问题,给出优化设计结果,以促进生物质发电工程的不断发展。     

袋式除尘器在20t／h锅炉除尘器改造中的应用

燃煤锅炉在运行过程中会排放出大量的烟尘,而使用电除尘器除尘,效率较低,已经不能满足新的排放要求,采用低压脉冲袋式除尘器对原电除尘器进行技术改造,结果表明,袋式除尘器的除尘效率达到99．9％,使烟尘排放浓度≤50mg／Nm^3,达到了当地环保部门的排放要求,取得了良好的社会和环境效益。     

长廊型建筑前室缓冲区对排烟效果的影响

高层建筑发生火灾时,采用加压防烟将会有大量的新鲜空气被送入着火层。这些新鲜空气稀释了烟气,从而降低了机械排烟效率。提出了高层建筑条形走廊前室缓冲区的设想,并通过高层建筑内烟气流动的数学模型,采用双方程三维紊流模型,对相同排烟量情况下前室缓冲区对排烟效果的影响进行了模拟计算和对比分析。结果表明：对条形走廊,前室缓冲区能够提高机械排烟效率近3.6%,同时在前室门附近走廊内形成一段相对安全的区域,有利于人员逃离着火层。