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1.
Summary The European policy on energy focus on the search for alternative and renewable sources of energy where forest biomass plays a significant role. In this article, calorific values of different kinds of forest residues (leaves, thin branches, barks, etc.) are reported. These values were measured by combustion bomb calorimetry with the objective of understanding, through different risk indices, the behaviour of forest waste in the case of wildfires, and also to study the use of forest residues as raw materials to be used as energy sources. The study was complemented with determination of elemental analysis, flammability using a standard epiradiator, thermodegradation analysis, and different mechanical tests trying to get relationships between thermal behaviour and some physical properties. The study was carried out on Eucalyptus globulus Labill and Pinus pinaster Aiton, because these forest formations have both high economical and ecological interest in Galicia (NW Spain).  相似文献   

2.
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.  相似文献   

3.
啤酒酵母废菌体吸附Pd2+的物理化学特性   总被引:8,自引:0,他引:8  
以啤酒酿造厂的啤酒酵母废菌体为生物吸附剂,研究死的啤酒酵母菌体从PdCl2溶液中吸附Pd2+的物理化学特性.结果表明,该菌体吸附Pd2+受吸附时间、溶液pH值、菌体浓度和Pd2+起始浓度等因素的影响.菌体吸附Pd2+是个快速的过程,吸附45min时吸附量达最大,但在最初的3min内,吸附量可达到最大吸附量的92%.在5~60℃范围内,吸附作用不受温度影响.吸附作用的最适pH值为3.5.在Pd2+起始质量浓度为30~300mg/L范围内和菌体质量浓度为2g/L的条件下,菌体对Pd2+的吸附作用符合Langmuir和Freundlich等温吸附模型.在pH=3.5,Pd2+与菌体质量比为0.2和30℃条件下吸附60min,吸附量达94.5mg/g.从废钯催化剂处理液回收钯,吸附量为32.2mg/g.XPS分析表明,该菌体能吸附水溶液中的Pd2+.TEM结果表明,在无外加电子供体时,死的啤酒酵母废菌体能够吸附和还原溶液中的Pd2+成Pd0微粒,Pd0微粒可进一步形成有一定形状的钯晶粒;该菌体还能使吸附在γ-Al2O3上的Pd2+还原成Pd0.  相似文献   

4.
亚临界水中生物固体废弃物水解产物中氨基酸的HPLC分析   总被引:1,自引:0,他引:1  
朱宪  宋宏立  程洪斌 《应用化学》2006,23(9):1052-0
亚临界水中生物固体废弃物水解产物中氨基酸的HPLC分析;亚临界水;生物质;固体废弃物;高效液相色谱;氨基酸;分析化学  相似文献   

5.
Evaluation of CSC charcoal by standard thermoanalytical techniques shows that the dry material contains ⪞ 99% carbon having calorific value of about 16.32 mJ/kg; its hydrogen and ash contents are insignificant. On admixture with small amount of K2CO3 (seed for generation of combustion plasma) its combustion characteristics remain more or less unaltered though the combustion rates are greatly enhanced. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

6.
采用氧弹燃烧法对垃圾样品干燥基进行前处理,用碳酸钠(24 mmol/L)和碳酸氢钠(30 mmol/L)以及过氧化氢(2.5%)为吸收液,并用离子色谱法对其处理后吸收液中氯离子和硫酸根含量进行测定,最后换算为样品中氯和硫的含量。氯和硫酸根质量浓度分别在1~50 mg/L与色谱峰面积呈良好的线性相关,其线性相关系数都大于0.999。样品中氯的加标回收率为96.5%~99.1%,硫酸根的加标回收率为92.5%~101%,测定结果中样品的相对平均标准偏差均小于3%(n=5),并用质控样品对方法进行了验证,结果表明样品的前处理方法简单、样品损失少、准确度高,适合于垃圾样品可燃组分中氯和硫含量的测定。  相似文献   

7.
通过对比废弃塑料(PE)和渣油的热重曲线(TG/DTG),研究了两者的热解特性,论证了利用延迟焦化方法处理聚乙烯类废弃塑料的理论可行性;同时通过模拟延迟焦化实验,针对性地考察了废弃聚乙烯延迟焦化及废弃聚乙烯与渣油共延迟焦化的反应特性,采用模拟蒸馏方法分析了燃料油产物的成分组成,探讨了废弃聚乙烯延迟焦化方法制取燃料油的生产可行性。结果表明,PE的主要热解温区为350℃~480℃,渣油的为250℃~460℃,两者的热解特性有很大的相似性。PE热解的液体产物中汽油和柴油馏分达到62%,蜡油馏分为38%;PE热解的气相产物为小分子的烃类和氢气。PE与渣油共延迟焦化的液体产物中汽油馏分明显比渣油单独焦化的增加。  相似文献   

8.
Waste plastics are non-degradable constituents that can stay in the environment for centuries. Their large land space consumption is unsafe to humans and animals. Concomitantly, the continuous engineering of plastics, which causes depletion of petroleum, poses another problem since they are petroleum-based materials. Therefore, energy recovering trough pyrolysis is an innovative and sustainable solution since it can be practiced without liberating toxic gases into the atmosphere. The most commonly used plastics, such as HDPE, LDPE (high- and low-density polyethylene), PP (polypropylene), PS (polystyrene), and, to some extent, PC (polycarbonate), PVC (polyvinyl chloride), and PET (polyethylene terephthalate), are used for fuel oil recovery through this process. The oils which are generated from the wastes showed caloric values almost comparable with conventional fuels. The main aim of the present review is to highlight and summarize the trends of thermal and catalytic pyrolysis of waste plastic into valuable fuel products through manipulating the operational parameters that influence the quality or quantity of the recovered results. The properties and product distribution of the pyrolytic fuels and the depolymerization reaction mechanisms of each plastic and their byproduct composition are also discussed.  相似文献   

9.
The enormous environmental problems that arise from organic waste have increased due to the significant population increase worldwide. Microbial fuel cells provide a novel solution for the use of waste as fuel for electricity generation. In this investigation, onion waste was used, and managed to generate maximum peaks of 4.459 ± 0.0608 mA and 0.991 ± 0.02 V of current and voltage, respectively. The conductivity values increased rapidly to 179,987 ± 2859 mS/cm, while the optimal pH in which the most significant current was generated was 6968 ± 0.286, and the ° Brix values decreased rapidly due to the degradation of organic matter. The microbial fuel cells showed a low internal resistance (154,389 ± 5228 Ω), with a power density of 595.69 ± 15.05 mW/cm2 at a current density of 6.02 A/cm2; these values are higher than those reported by other authors in the literature. The diffractogram spectra of the onion debris from FTIR show a decrease in the most intense peaks, compared to the initial ones with the final ones. It was possible to identify the species Pseudomona eruginosa, Acinetobacter bereziniae, Stenotrophomonas maltophilia, and Yarrowia lipolytica adhered to the anode electrode at the end of the monitoring using the molecular technique.  相似文献   

10.
简单介绍了生物柴油的生产原料,综述了用废弃油脂生产生物柴油的现状和方法。废弃油脂生产生物柴油的方法主要有物理法和化学法,物理法主要有掺和法和微乳法,化学法主要有热裂解法和酯交换法。目前生产中采用化学法的酯交换法、以酸碱两步催化法的工艺为主,而生物酶法和超临界法是研究热点。  相似文献   

11.
从污水微生物合成聚羟基烷酸酯   总被引:1,自引:0,他引:1  
聚羟基烷酸酯(PHA)是一类具有生物相容性、光学活性、热塑性和完全生物降解性等的生物高分子,具有巨大的应用前景.PHA是一些微生物在不平衡生长条件下胞内能量和碳源储藏物质,可通过微生物发酵合成[1,2].目前大幅度降低PHA的成本一直是国内外研究者关注的难题.通常处理有机废水的活性污泥中含有多种可积累PHA的天然微生物[3],故可以利用污水中的有机物和混合菌种群合成PHA,降低PHA的成本[4,5].本工作以某纺织厂的工业废水和城市生活污水为原料,采用微嗜气-好气过程驯化活性污泥,研究了供氧量、碳源调节物浓度、培养时间、温度等因素…  相似文献   

12.
This paper discusses waste disposal of nuclear fuel from atomic power plants (APPs). The state of fragmentation platinum metals (ruthenium, palladium, and rhodium) and their distribution in waste disposal processes are analyzed. The state of fundamental research on the coordination chemistry of these metals in nitrite and nitrate solvents is characterized for technological design of methods for the separation of valuable components.  相似文献   

13.
The excessive use of fossil sources for the generation of electrical energy and the increase in different organic wastes have caused great damage to the environment; these problems have promoted new ways of generating electricity in an eco-friendly manner using organic waste. In this sense, this research uses single-chamber microbial fuel cells with zinc and copper as electrodes and pineapple waste as fuel (substrate). Current and voltage peaks of 4.95667 ± 0.54775 mA and 0.99 ± 0.03 V were generated on days 16 and 20, respectively, with the substrate operating at an acid pH of 5.21 ± 0.18 and an electrical conductivity of 145.16 ± 9.86 mS/cm at two degrees Brix. Thus, it was also found that the internal resistance of the cells was 865.845 ± 4.726 Ω, and a maximum power density of 513.99 ± 6.54 mW/m2 was generated at a current density of 6.123 A/m2, and the final FTIR spectrum showed a clear decrease in the initial transmittance peaks. Finally, from the biofilm formed on the anodic electrode, it was possible to molecularly identify the yeast Wickerhamomyces anomalus with 99.82% accuracy. In this way, this research provides a method that companies exporting and importing this fruit may use to generate electrical energy from its waste.  相似文献   

14.
采用超临界CO2萃取技术提取废次烟叶中的茄尼醇   总被引:1,自引:0,他引:1  
采用超临界CO2萃取技术提取废次烟叶中的有效成分茄尼醇,以乙醇为夹带剂,研究了萃取压力、萃取温度、CO2的流量、萃取时间、夹带剂的使用、分离温度和原料粒度等方面对萃取效果的影响,并对其中影响较为显著的因素进行了正交试验,通过极差和方差分析确定了萃取体系适宜的工艺条件。萃取压力为20 MPa,萃取温度为45℃,CO2的流量为15 L/h,萃取时间为2 h,夹带剂为95%的乙醇,分离温度为40℃,原料粒度为40~60目。  相似文献   

15.
This paper presents the results of research on the granulation process of leather industry waste, i.e., tanning shavings. It is economically justified to granulate this waste together with mineral additives that are useful in the processes of their further processing. Unfortunately, the granulation of raw, unsorted shavings does not obtain desired results due to their unusual properties. In this study, the possibilities of agglomeration of this waste were examined by a new method consisting of the production and then the granulation of wet pulp. During granulation, no additional binding liquid is added to the granulated bed. As part of this work, the specific surface of granulated shavings, the granulometric composition of the obtained agglomerates, and their strength parameters were determined. The use of a vibrating disc granulator, the addition of a water glass solution (in the pulp), dolomite, and gypsum made it possible to obtain durable, mechanically stable granules.  相似文献   

16.
固定化脂肪酶催化高酸废油脂酯交换生产生物柴油   总被引:42,自引:0,他引:42  
陈志锋  吴虹  宗敏华 《催化学报》2006,27(2):146-150
 探讨了固定化脂肪酶Novozym 435催化高酸废油脂与乙酸甲酯酯交换生产生物柴油. Novozym 435能催化高酸废油脂与乙酸甲酯的酯交换反应,反应24 h后甲酯产率为77.5%,但该值大大低于以精制玉米油为原料时的甲酯产率(86.2%). 系统研究了反应体系中的水、游离脂肪酸和乙酸对反应的影响. 当反应体系中的水含量低于0.05%时,水对酶反应速率和甲酯产率影响甚小,而水含量高于0.05%时,酶反应速率和甲酯产率随着水含量的增加而降低. 游离脂肪酸对反应有较大影响,甲酯产率随着游离脂肪酸含量的增加而急剧下降. 乙酸甲酯与游离脂肪酸反应产生的副产物乙酸是导致甲酯产率显著下降的原因. 在反应体系中添加适量(油重的10%)的有机碱三羟甲基氨基甲烷或三乙胺可有效提高酶促高酸废油脂的酯交换反应速率和甲酯产率,使反应12 h后的甲酯产率分别达到85.9%和80.8%; 碱的加入还提高了酶的操作稳定性,添加有机碱三羟甲基氨基甲烷或三乙胺可使反应10批次后Novozym 435的相对酶活力分别由对照值86%提高到97%和93%.  相似文献   

17.
18.
In the present paper, boron removal from aqueous solution by adsorption was investigated and 23 full factorial design was applied. Non activated waste sepiolite (NAWS) and HCl activated waste sepiolite (AWS) were used as adsorbents. Regression equation formulated for boron adsorption was represented as a function of response variables. The results obtained from the study on parameters showed that as pH increased and temperature decreased boron removal by adsorption increased. Adsorbed boron amount on AWS was higher than that of NAWS. Maximum boron removal was obtained at pH 10 and 20°C for both adsorbents. Adsorption data obtained from batch adsorption experiments carried out with NAWS and AWS fitted to the Langmuir equation. The batch adsorption capacities were found in mg/g: 96.15 and 178.57 for NAWS and AWS, respectively. The capacity value for column study was obtained by graphical integration as 219.01 mg/g for AWS. The Thomas and the Yoon-Nelson models were applied to experimental data to predict the breakthrough curves and to determine the characteristic parameters of the column useful for process design.  相似文献   

19.
Phosphorus raw materials are non-renewable, and their resources are shrinking faster and faster as a result of increased fertilizer production. This is due to the increasing population and the need to produce more food. Phosphorus, on the other hand, is one of the main nutrients of plants, without which it is impossible to conduct intensive agricultural production. There are no economically significant phosphate resources in Europe, so they must be imported. That is why it is so important to reduce losses and recover this element from waste streams, which was reflected in the new EU Regulation 2019/1009. A prospective option is to use waste phosphates from the production of polyether polyols. Previous studies show that they contain about 20% phosphorus. Due to their high water content, the most advantageous form of their application is the production of fertilizers in the form of a suspension. The aim of the study is to assess the possibility of using waste phosphates from the production of polyols as raw materials for the production of suspension fertilizers.  相似文献   

20.
环烷酸铈消烟助燃剂改善内燃机有害排放的研究   总被引:3,自引:0,他引:3  
消除柴油机排放污染应当主要限制柴油机颗粒排放水平。研究具有助燃与消烟作用的柴油添加剂自然成为降低柴油机颗粒排放的重要途径。通过台架试验考察环烷酸铈消烟助燃剂加剂前后发动机的排气烟度、速度特性、负荷特性,以及排气温度等指标,结果表明环烷酸铈消烟助燃剂可降低内燃机排放中的NO2,CO化合物或碳烟等有害物质,特别对碳烟、NO2排放平均下降幅度较大。  相似文献   

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