外文翻译--太阳能增温丘陵地区沼气厂实地考察.doc

沈阳农业大学学士学位论文外文翻译外 文 翻 译题 目： 太阳能增温丘陵地区沼气厂实地考察 太阳能增温丘陵地区沼气厂实地考察摘要：目前的研究客观的表明采用塑料材料代替传统的砖材料作为沼气厂保温材料效果更好。在装有太阳能研究及其对沼气生产的影响的小村庄该领域的研究进行了一年（2005年10月，2006年9月）。在夏季（4月-6月）温度达到最高21-25c，达到最低10-13c。在冬季（10月-12月）温度达到最高16-21c，最低达到2c一下。在研究区的太阳辐射范围从250-600w/m2。这项研究涉及控制常规模型（印度的标准模型，在印度的大部分现行仅适用于砌体结构）和实验类似容量瓶的温室塑料桶。能源可持续发展在实验室规模的沼气池采用塑料材料超过其它材料的试验结果给了我们很大的信心，进一步开展该试验的研究。在继续的研究里，一年时间使用55天，生产沼气的目的是用来烹饪和照明。这一年里控制温度在22.4-26.3c，沼气池所在环境温度为17c。由此可以得出结论辅助日光温室塑料厂的沼气，可以有效地在丘陵地区的一些小的调整，开始采用的温度分布在沼气生产中扮演了重要作用。关键词：太阳能温室；沼气厂；温度1.介绍沼气发电消耗大约四分之一的粪便，但可用热气体比直接燃烧的牛粪全部数额得到的多20左右。这主要是由于利用率高效率（60）的沼气与效率低下直接烧牛粪饼（11）的原因。几千年的沼气发电厂已建成在发展中国家。仅在印度，有估计超过250万头牛和粪的三分之一，如果每年从这些生产可用于生产沼气，可以安装超过12万沼气。除此之外，在现有的设计和厂房建设细看可以导致沼气的优化理论。沼气厂的设计，可以优化为轻度钢沼气的成本，而不是仅仅的整体成本。尝试用不同的材料的基础上，安装成本是高度依赖沼气厂制造。大多数金属沼气池放在地下，沼气池进度对地面平均气温的温度可以维持温度较高，但成本，运行和维护，腐蚀问题和传热性能使得它不合算。在传统的水泥设计，在添加挖裂缝的形成和扩展的安装时间被认为是主要的缺点。pvc温室结构安装允许从18的地底下太阳能加热到约37。对这些研究的效率进行研究，然而，由于重视不够，能量增益和损失机制的意义有限。在冬季的最佳状态，需要一个封闭的环境中。这条件是，取得了抗紫外线的透明塑料盖，一般被称为冬季温室。但紫外线稳定聚丙烯是不能耐温度高于50c，并因此变得脆弱和其随时间变化透明度降低。传统的沼气利用太阳能建议增加保温材料温度，避免影响沼气的输出。据观察，从一个传统的比较研究和太阳能加上辅助温室沼气工程，泥浆温度可从20c（在传统的植物）提高到近35，以达到厌氧发酵的最佳温度。在拉瓦尔大学在冬季寒冷地区已制定一个新的温室设计。已发现减少30-40的要求相比的一个标准的双层塑料覆盖温室加热。一般情况下，虽没有法则，但最佳工艺条件稳定，应仔细调节工作温度。作为一项安全措施，它是一种常见的做法，要么埋在地面上的土壤有利的绝缘性能的帐户中的沼气池，或使用温室覆盖。它已被证明，利用太阳能（温室效应）期间实现沼气生产的最佳温度降低。在寒冬季节，在印度北部丘陵地区的环境温度低于10。由于温度较低，沼气有利于生产急剧下降，并可能会停止。由于温度较低，沼气有利于生产急剧下降，并可能会停止。因此，为提高沼气生产，较高的蒸煮温度比环境温度是必需的。此外，期间所需的沼气产率，实现最适宜的温度应降低。沼气系统的规模和成本可以降低。绿色房子的概念应纳入更大容量的生物气体工厂。2材料和方法在丘陵地区进行实地考察，它坐落在海拔900-2636以上平面。其纬度和纵向尺寸为130公里（纬度：10-38wp11-49n）其经度和横向尺寸为185公里（东经：76.0-77.15e）沼气厂的安装费用由建设材料，其中许多参数是一个重要的影响。编造材料，如锡的导热性，铜，砖石，水泥混凝土，干土，湿土，塑料，铁，不锈钢。实验的沼气厂建在地上的塑料水箱分别为高度，直径和厚度157厘米，135厘米和6毫米。实验沼气厂被置于太阳下与印度传统的水泥标准沼气厂（迪恩- abandhu模型）作对照。做饭利用沼气厂产生的气体（燃烧器）和照明（灯）的目的。一年半连续研究是从2005年10月-2006年9月，2006年的平均值分别采用皮尔逊积差相关系数法统计表。保留时间保持在55天。环境和泥浆温度记录每小时的基础上，使用所有的实验和每天的平均年龄校准的热电偶（由上午七时至下午6时）。每小时监测太阳辐射（上午七时至下午6时），为所有的实验使用校准太阳辐射。天然气产量记录得每天一个一公升容量（insref气体的流量计，印度）和甲烷气体的湿式气体流量计的研究中使用气相色谱仪（aimil nucon月两次系列，印度）。物理化学分析sis（elico系列-li610，印度），如ph值，总固体，添加到进水和作废的污水沼气的挥发性固体在一个月内两次是1992年采用的方法分析。四名成员组成的家庭的沼气用于做饭和照明的应用也被记录，每月两次。3.结果与讨论有人企图利用沼气厂作为非腐蚀性等物理和化学性能关系的一些选择的原因可以归结为制造塑料材具有良好的绝缘体热，较轻的重量和更大的耐用性。此外，塑料材料具有强大到足以承受的工作温度及长时间暴露在阳光下。塑料沼气厂是相对便宜，从这些材料制作，其性能已经发现，要加强。目前的研究进行了一场大型沼气厂2.0m3在不同条件下的能力。协助温室和控制沼气厂，是传统的模型，并在丘陵地区作了比较集中的制作材料和温度的影响塑料桶的沼气植物。每年的平均值记录在实验组和对照沼气理化参数下，在黄土丘陵区的比较研究如表1所示。在实验组和对照沼气监测年均温度为下列数据，分别为26.3c和22.4c对17.0c和在泥浆温度记录相应上升的环境温度下的环境条件比高出35.3和24.0。在实验的沼气厂地面和环境条件的温度变化与太阳辐射方面的代表见图.1。年均温室室温度记录是29.1c。沼气植物每年平均产气率分别为39.1公斤和34.6公斤每1天。在冬季的天然气产量低于其他月份。在实验的沼气厂的平均天然气产量在冬季季风后，夏季季风前季节的分别为1053.3，1193.3，1263.3和1183.3公斤每天。从实验和控制沼气的产气率记录得最大的天然气生产在夏季时，周围只有18c，由31.5c温室室内温度的热量转移到水泥砂浆的28.3c。记录得最大的天然气生产在夏季环境温度在19下时，泥浆温度在23.6c。在生产沼气的差异率为33.7。在冬季的几个月里沼气生产速率与暑假期间生产的沼气厂相比削减约77。在环境温度变化下影响植物比影响传统的植物更有效果。表1.物理化学参数的实验和控制沼气厂（每年）参数塑料油箱（实验）沼气厂（对照组）沼气厂ts（）初始最后7.60.6vs(%)初始75.461.92.7最后49.16.3ph初始6.66.5最后7.0沼气的甲烷比例（）64.13.059.94.5平均产气率（新鲜的输入每公斤每天）39.13.634.63.1天然气产量（固体减少每公斤每天）0.7太阳辐射（w/m2）3904539045浆料温度（）26.31.722.41.1地面温度（）17.61.317.31.3环境温度（）17.01.317.01.3温室温度（）29.11.829.11.8注：值的范围是“”表示在平原地区的实验和控制沼气植物每年平均甲烷气体分数值分别为64.1和59.9。甲烷气体的平均分数在实验沼气厂是61.4,61.8，67.3和65.9，在冬季季风后，夏季和预季风季节和相应的甲烷沼气厂控制分数值是56.8，55.8，64.0和63.1。据观察，记录在实验沼气厂的甲烷气体分数为6.5。甲烷气体方面的实验和控制沼气ph值记录数据，在实验组和对照沼气厂的进水ph值平均为6.6和6.5。在实验组和对照沼气纯植物每年的平均ph值地区分别为7.0和7.2。研究结果还表明，其次是ph值7.0时最佳的天然气生产速率，ph值4.0出现过生产的天然气呈酸性。最适ph值介于7.0和7.2，但天然气产量是6.6和7.6之间相当稳定。当ph值低于6.6时，有发生甲烷菌显着的抑制作用，当它下降到了6.2的价值，沼气池内容易使这些细菌产生毒性。图1.太阳辐射温度的变化，实验组和对照沼气（按季节）在做饭和照明时，产生沼气在黄土丘陵区的比较研究在实验组和对照植物（按季节）的时间消耗在表2所示。在这项研究中，做饭没有在冬季期间，由于可用性低沼气，并在此期间产生的气体利用照明应用，使沼气灯照明，也解放了的热辐射，提高最终用户的舒适室温条件下。主要部分产生的沼气利用，对在本研究中的植物实验组和对照沼气做饭照明应用。白天和晚上的温差很大，它会影响细菌的生长速率。因此，在性能上减少遇到在现有的常规设计。但是，使用沼气厂制造的塑料将克服上述所有问题。一旦安装传统设计，则所有传统设计不能迁往其他任何场合。但是，在目前这个研究确定塑料沼气厂可在任何时候转移到任何方便的地方。表.2实验和控制沼气厂（按季节）用于做饭和照明的时间消耗季节消耗的时间（小时：分钟）温室篷（实验）沼气厂没有温室篷（对照组）沼气厂做饭照明做饭照明冬季（2005年10月至12月）-0:28-0:18季风（2006年1月至3月）0:250:420:150:28夏季（2006年4月至6月）1:260:470:270:33季前风（2006年7月至9月）0:250:330:130:22每年的总时间消耗4:104:502:053:054.结论在本研究中，作为替代建材沼气厂在丘陵地区日光温室，塑料测试，证明是有效的，在印度的大部分地区被采纳的模型比其他传统的砖石效果要好的多。在环境温度为17时，控制沼气发电厂年均泥浆研究期间记录得的气温是26.3和22.4。显而易见的是，记录在塑料和常规控制沼气浆料温度分别比环境条件上升为35.3和24.0，在实验的沼气厂年均温室室内温度记录是29.1。据观察，比对照沼气厂，记录在实验沼气厂的天然气产量是11.5。本次调查的实验产生的数据库的基础上，可以得出结论，有一个良好的范围，聘请沼气工程建设，并进一步研究塑料材料证明了这种方法的可行性。由爱思唯尔有限公司主办2008z3-d0491原文出处：department of bio-energy,school of energy,environment and natural resources,madurai kamaraj university,madurai 625 021,tamil nadu,india received 17 april 2007;received in revised form 1 december 2007;accepted 18 march 2008 available online 14 april 2008solar greenhouse assisted biogas plant in hilly regiona eld studyabstract:the present study was undertaken with the objective of evaluating plastic as an alternative material for biogas plant on a par with conventional brick material material.the eld study was carried out for one year(october,2005september,2006) in a small hamlet at nilgiris incorporating solar energy to study its inuence on biogas production. during summer (apriljune) the temperature reaches to the maximum of 2125and the minimum of 1012.during winter(octoberdecember),the temperature available is maximum of 1621 and minimum of 2.the solar insolation in the study area ranges from 250 to 600w/m2.in continuation,a semicontinuous study was conducted for one year with the retention time of 55days.the gas generated from the biogas plants was utilized for cooking(burner) and lighting purposes.the yearly average slurry temperatures recorded during the study period was 26.3 and 22.4 in experimental and control biogas plants against ambient temperature of 17.0.the yearly average gas yield from the experimental and control biogas plants were 39.1and34.6lkg-1day-1respectively.gas productions in the winter season registered lower than other months.it can be concluded that the solar greenhouse assisted plastic biogas plant can be eciently adopted with minor modications in hilly regions since the temperature prole plays a major role in biogas production.keywords:solar;greenhouse;biogas plant;temprature1.introductionbiogas generation consumes about one-fourth of the dung, but the available heat of the gas is about 20% more than that obtained by burning the entire amount of dung directly. this is mainly due to the high efficiency(60%) of utilization compared to the poor efficiency(11%) of burning dung cakes directly.several thousand biogas plants have been constructed in developing countries.in india alone,there are an estimated over 250 million cattle and if one third of the dung produced annually from these is available for production of biogas,more than 12 million biogas plants can be installed.in addition to this,a closer look at the existing designs and plant construction can lead to an optimization theory for biogas plants.biogas plant designs could be optimized for the overall costs rather than merely for the cost of the mild-steel biogas oating drum as those were being done earlier.the fabrication of biogas plant is tried with different materials based on which the cost of installation is highly dependent.most metal digesters are placed underground,where the temperature of the digester progress towards the average temperature of the ground that could maintain higher temperatures but cost,operation and maintenance,corrosion problem and the heat transfer properties makes it uneconomical.in conventional cement designs,in addition to digging the formation of cracks and the extended installation time are considered to be major drawbacks.installation of pvc greenhouse type structure over a biogas plant allowed solar heating of the substrate from18 to about 37.considerable efforts have been devoted in this direction,which resulted in the development of several conceptsviz.constructing greenhouse and shallow solar pond over the dome,use of insulation around the digester. the investigations carried out for studying the efficiency of these concepts, however,have limited signicance due to inadequate attention to the mechanism of energy gain and loss.this condition is achieved in a greenhouse constructed with uv-resistant transparent plastic cover,generally known as winter greenhouse.but uv-stabilized propylenelm is not resistant to temperatures higher than 50,and it therefore becomes brittle and its transparency decreases with the time.this was most probably due to the increasing opacity of the cover and the increasing number of throne areas.the use of solar canopy over the conventional biogas plants was suggested for increasing the slurry temperature and hence the output of biogas.it has been observed from a comparative study of the conventional and the solarassisted greenhouse coupled biogas plant that the temperature of the slurry can be raised from 20to nearly 35,the optimal temperature foranaerobic fermentation.a new design of greenhouse had been developed for colder regions at laval university during winter season.a reduction has been found in the heating requirements of 3040% compared to a standard,double layered plastic covered greenhouse.in general,there is no rule of thumb,but for optimum process stability, the temperature should be carefully regulated within a narrow range of the operating temperature.as a safety measure,it is a common practice either to burry the digesters in the ground on account of the advantageous insulating properties of the soil,or to use a greenhouse covering.due to the lower temperature, biogas production decreases drastically and may stop.thus,for enhancing biogas production,a higher digester temperature than ambient temperature is required.also,for a required production rate of biogas,the period to achieve the optimum temperature should be reduced. the size and cost of the biogas system can be reduced.the greenhouse concept should be integrated for larger capacity biogas plant.2.materials and methodsthe eld study was carried out in a small hamlet namely kadaladu 9 km from nilgiris.it is situated at an elevation of 9002636m above msl.its latitudinal and longitudinal dimensions being 130km (latitude:1038wp1149n)by 185km(longitude:76.077.15e).the installation cost of biogas plant is inuenced by many parameters among which construction material is an important one.the experimental biogas plant was constructed from over head plasticwater tank with height,diameter and thickness of 157cm,135cm and 6mm,respectively.experimental biogas plant was placed above ground covered with greenhouse canopy(experimental biogas plant) which was compared against indian standard conventional cement biogas plant which serves as control.the gas generated from the biogas plant was utilized for cooking(burner) and lighting purpose.semi-continuous study was conducted for one year from octoberseptember,2006 and the averaged values were tabulated statistically adopting pearsons product moment correlation coefficient method retention time was maintained at 55days.ambient and slurry temperatures were recorded on an hourly basis (from 7a.m. to 6p.m.) using calibrated thermocouples for all the experiments and averaged per day.solar insolation was also monitored on an hourly basis (from 7a.m.to 6p.m.) using calibrated suneters for all the experiments and averaged per day.gas production was recorded on a daily basis with wet type gas ow meters of one litre capacity(insref gas ow meter cat.no.iri.06a,india) and methane in the gas was studied twice in a month using gas chromatograph.the application of biogas (family of four members) for cooking and lighting was also recorded twice a month.3.results and discussionan attempt was made earlier by utilizing plastic materials for the fabrication of biogas plant,the reasons for the selection can be attributed to some of their physical and chemical properties such as noncorrosivity,good insulator for heat,light in weight and greater durability.in addition,plastic material is strong enough to withstand operating temperatures and prolonged exposure to sunlight,refabricable and attractive.the plastic biogas plant is relatively cheaper to fabricate from these materials and also its performance has been found to be enhanced.the present study was carried out in field-scale biogas plants of 2.0m3capacity at different conditions.the experimental biogas plant was made of plastic tank assisted with greenhouse and the control biogas plant was the conventional deenabandhu model and comparison was made focussing on fabrication material and effect of temperature in hilly region.the averaged values per year recorded for physicochemical parameters in experimental and control biogas plants under the comparative study in hilly region are shown in table1.he yearly average slurry temperatures on itored in experimental and control biogas plants was26.3and 22.4,respectively against ambient temperature of 17.0 and corresponding rise in slurry temperature recorded was 35.3 and 24.0% higher than the ambient condition.the temperature variation in slurry, ground and ambient condition with respect to solar insolation is represented in fig.1.the yearly average greenhouse chamber temperature recorded was 29.1in the experimental biogas plant.the yearly average gas yield from the experimental and control biogas plants were 39.1 and 34.6lkg-1 day-1.gas production in the winter season was lower than other months.average gas yidld in experimental biogas plant experimental were1053.3,1193.3,1263.3and1183.3kg-1day-1during winter,postmonsoon,summer and pre-monsoon seasons respectively.the methane content of biogas of both the plants was almost identical,but the moisture in the gas was 43% higher in the rubber-balloon plant than the plant.the changes in ambient temperature affected the rubber-balloon plant more than they affected the conventional plant.table 1physico-chemical parameters for experimental and control biogas plant(annual basis)parametersplastic tank(experimental)deenabandhu(control) biogas plantts(%) initial12.112.1ts(%) final0.4vs(%) initial74.574.5vs(%) final49.16.361.92.7ph initial6.66.5ph final7.0methane fraction of biogas (%)64.13.059.94.5slurry temperature ()26.31.722.41.1ground temperature ()17.61.317.31.3ambient temperature ()17.01.317.01.3greenhouse chamber temperature()29.11.829.11.8note:the range of values is indicated by ”the values of yearly average methane fraction of gas for the experimental and control biogas plants in plain region was 64.1 and 59.9%,respectively.the average methane fraction of gas in experimental biogas plant was 61.4,61.8,67.3 and 65.9% during winter,post-monsoon, summer and pre-monsoon seasons and the corresponding methane fraction value in the control biogas plant was 56.8,55.8,64.0 and 63.1%.it is observed that methane fraction of gas recorded in experimental biogas plant was 6.5% higher than the control biogas plant.the average ph value in the inuent in the experimental and control biogas plants was 6.6 and 6.5. the yearly average ph value in the experimental and control biogas plants in plain region were 7.0 and 7.2, respectively.the ph in the post- monsoon season (juneaugust,2006) recorded near neutrality than other months.the results also show that optimal gas production occurs at ph of 7.0 followed by 9.0 while ph of 4.0 appears too acidic for meaningful gas production.the optimum ph lies between 7.0 and 7.2,though gas production is fairly stable between 6.6 and 7.6.when ph drops below 6.6,there occurs a signicant inhibition of methanogenic bacteria and when it drops to a value of 6.2,the digester contents become toxic to these bacteria.fig.1.temperature variations with respect to solar insolation for experimental and control biogas plants (seasonal basis)the time consumption for cooking and lighting from generated biogas (seasonal basis) in experimental and con- trol biogas plants under the comparative study in hilly region is shown in table2.during this study,the cooking was not done in winter period due to low availability of biogas and the gas generated during this period was utilized for lighting application so that the illumination from the biogas lamp also liberated heat radiation to raise the room temperature conditions for comfort of endusers.the major portion of the biogas yielded was utilized for lighting application against cooking both in experimental and control biogas plants in the present study. the temperature reversal during day and night variationsdiffers far from the ambient conditions;it affects the bacterial growth rate.thus,reduction in the performance is encountered in the existing conventional designs.but,use of plastic in biogas plant fabrication will overcome all the above problems.all the conventional designs once installed can not be relocated on any other occasions.but,the plastic biogas plant identied in this present study can be shifted to any convenient place at any time (can be placed outdoors in summer season and indoors during winter season). the sand and sediment depositions in the conventional indian standard design if not removed at regular intervals will bring down the retention time and ultimately the drop in its performance.more over,the gas yield recorded in experimental biogas plant was 11.5% higher than the control biogas plant.table 2time consumption for cooking and lighting from experimental and control biogas plant (seasonal basis)seasonstime consumption(hrs:min)plastic tank with greenhouse canopy (experimental)biogas plantdeenabandhu without greenhouse canopy (control)biogas plantcookinglightingcookingl