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水煤气行业的工业革命  两步法制造水煤气新工艺的的研发将大大提高了没得利用率。  水煤气行业的“工业革命”——“两步法水煤气制造工艺”  刚刚进入二十一世纪,人类就惊讶的发现,伴随新科技,新文明的到来.能源危机的红灯频频亮起.石油危机,煤炭危机,天然气危机等等,一次次发难,像一只只大手扼住人类赖以生存的血液.中国能源告急,西欧能源告急,北美能源告急,一时间能源问题实实在在摆在了人类面前.能源关乎国家的兴衰,民族的存亡,甚至关系到整个人类的生存。为应对能源问题,欧盟发布了《欧盟能源供应安全绿皮书》《能效行动计划》,日本颁布了《关于能源使用合理化的法律》即《节能法》、《促进石油替代能源的开发和导入的相关法令》即《石油替代能源法》,美国则推出了《国家能源政策法--2005》。中国也起草颁布了《能源法》和《可再生能源法》.一些高瞻远瞩的企业家也适时研发了新技术、新设备.”两步法水煤气制造工艺”就是洛阳豫燃煤气设备公司为应对新世纪能源问题而研发的环保节能技术.它具有高效、节能、环保等特性.符合党的“十七大”所提出的“抓好节能减排工作,着力推进资源节约型、环境友好型社会建设”所要求的成功典范.  专利技术与传统工艺的对比  两步法制气工艺(专利号:4)仍采用固定床煤气炉,利用加热的空气来吹风,高温高热的蒸汽制气,对加套锅炉进行特殊的保温处理;控制制气阶段气化区最下部未烬燃料温度,不低于碳氧反应的过渡控制温度,不使气化层下部未燃尽的炭层温度在制气后期降至复燃点以下,确保了整个循环过程中火层稳定不上移。这样,两步法制气工艺仅有短时吹风和上行制气两个过程,大大简化了工艺过程,提高了单炉生产强度,消除了间歇制气过程中各个步序频繁切换带来的低产高耗问题,并克服了富氧连续制气所需的高昂制氧成本。对于两步法仅有上行制气,炉上带出热量较多,可通过空气预热器、蒸汽过热器将空气和蒸汽预热,回收这部分热量再用于制气,这样就将热量损失降到了最低,同时也提高了供热水平,稳定了火层。  现今广泛使用的工艺仍是传统的五步法,该工艺主要是:空气吹风、上行制气、下行制气、二次上行制气、空气吹净五个阶段循环.由于共用管道多,每个阶段的实现靠阀门控制,阀门切换频繁,占用大量时间,导致制气强度降低。制气主要在上行制气阶段进行,在煤气产量达到最大值后,随着床层温度降低迅速下降,下行制气阶段煤气产量大部分时间低于平均值;二次上行制气主要目的是为了安全考虑,空气吹净阶段主要是为了回收煤气炉上部空间和管道里的煤气。因此整个循环过程制气强度不高,效率低下。由于多步循环难以实现高效短循环制气;制气阶段持续时间长,吸热量大,整个循环过程温度大起大落,平均温度低,蒸汽分解率低;同时由于整个循环多步交替,有效制气时间短,热损失大;防挂壁的加套锅炉设计增加了散热损失,因而能耗高,耗煤量大.  国内现在的中小型氮肥厂主要采用固定床常压制气.由于国家对环保问题的重视及建立节约型社会的要求,固定床造气审批有一定难度.而两步法工艺由于采取了多种措施对煤气进行降温和清洁处理:首先利用热交换器进行降温和粗除尘,再通过洗气箱、洗气塔、脱硫塔和填料塔进行洗涤、脱硫、和脱萘,使煤气的洁净度完全满足连续生产的需要,并符合环境保护和节约能源的要求.  二步法新工艺的实践  山西芮城县某医药包装业有限公司是一家新型现代化企业,建厂数年来一直使用液化气生产,随着液化气价格节节攀升,产品成本大幅增加,在市场竞争中处于劣势,陷于进退维艰的处境。在2006年5月引进洛阳豫煤燃气设备公司先进技术,率先在本企业使用两步法水煤气制造工艺,并于2006年7月装置建成后达到了出人意料的效果。设备运行至今,不仅给企业带来巨大的经济效益,而且也充分验证了两步法工艺确实有效的解决企业所面临节能减排的难题.  两步法制气新工艺的优点:  1 降低能耗幅度大  以在芮城安瓶厂煤气站耗煤7~8吨/天,与同等产气量的五步法制气装置的10~12吨/天相比,能耗降幅近30%;与每天使用两吨多液化气相比,节约能源费用近50%。  2 所产煤气稳定,热值高  经该厂化验室化验分析,煤气热值在2800~2900千卡/标准立方米。  3 煤气纯净度高  本装置运行所产的煤气满足了其生产技术改造和正常生产的要求,未出现过堵塞灯头现象。  4 同步优化效应  由于采用新工艺所产煤气热值高、稳定性好,使得企业的一些技术改造项目得以实施,以安瓶厂为例,班产达到22万只左右,增长率达20 %而且基本能达到无人操作的水平。由于能耗低,使安瓶生产成本大大降低,使企业摆脱了难以生存的困境,在全国安瓶行业站稳了脚跟。  新工艺的前景分析  当今中国已成为煤炭、钢铁、铜等世界第一大消费大国、继美国之后的世界第二大石油和电力消费大国.《南方网讯》报道”尽管石油、天然气消费迅速增加,但综合国内外的各种预测,到2020年,煤炭在中国一次能源消费结构中仍将占第一位,达60%左右.”中国煤炭工业协会会长范维唐在国务院发展研究中心主办的能源战略和政策国际研讨会上说,目前煤炭在中国的一次能源消费中占67%,而世界平均水平是25%.在利用煤炭过程中,存在环境污染严重的问题.为此中国政府已经出台相关政策,支持洁净煤技术发展。解决中国能源需求,提高能源的开发和利用效率应摆在首位。节约能源已经被专家视为与煤炭、石油、天然气和电力同等重要的“第五能源”.  洛阳豫燃煤气设备公司独创的两步法水煤气生产工艺,克服了五步法制气碳转化率低、热效率低的顽症,又克服了固定床富氧连续制气过程中二氧化碳含量高等问题,具有很高的经济效益和社会效2008/7/11益。如用于老厂改造,设备改动小,不中断生产,易于实施。芮城安瓶厂煤气站,仅以百余万元的投资在较短的时间内就取得了巨大的成就,就是一个很好的例证.  新工艺的经济效益和社会效益  现今全国大中型化肥厂及制碱厂有700余家,而90%的企业采用的仍是落后的即将被淘汰的五步法制气工艺。该工艺煤耗大,生产效率低,煤气热值低、清洁度低。如果引进两步法制气工艺或进行两步法制气工艺改造,则仅需600万至1000万元人民币,且不中断生产,易于实施。若以每家企业每天耗煤500吨计,再以适宜条件下最低18%的节煤率计算,那么每家企业每年至少可节省2000多万元的能源消耗成本,行业可节省数百亿元的能源资金。自2003年以来能源价格居高不下并以双位数的增率不停攀升,仅2008年1-6月份煤炭价格就上涨了48%,给耗煤企业带来巨大的生产和经济压力,因而两步法制气工艺所带来的经济效益将会越来越可观。节约就是盈利,节约就是增加竞争力,节约就是一个优秀国人爱国的具体体现。  单纯从资源量的角度看,中国煤炭资源如果按年产25亿吨原煤来推算也仅可供应80年。党的十七次代表大会明确提出建设环境友好型社会和资源节约型社会的科学发展观。改变透支资源求发展的方式,转换经济发展的路径和模式,扭转“高投入、高消耗,高排放、不协调、难循环、低效益”的粗放型经济增长方式,逐步建立起资源节约型产业体系和消费体系。节能与环保已成为时代的主题。洛阳豫燃煤气设备公司研发的“两步法制气工艺”以其高超的节约性能和优越的环保性能完全契合这个时代主题,是通向黎明的一道曙光。该工艺若在制气行业得到全面推广,将使整个制气行业接近或达到欧美发达国家同期先进水平。给整个制气行业乃至整个国民经济带来新的生机。两步法制气工艺的应用和推广蕴含着无尽商机。十七大为实现全面建设小康社会提出了更高的目标和要求,每一个有责任的企业家,每一个有理想的公民都应尽自己的一份力量。我们期待着两步法制气工艺全面推广的一天早日到来。  ------------------------------  The Industrial Revolution of Water-gas industry  Two-step method to create water-gas research and development of new technology will greatly improve the utilization rate did not have   Water-gas industry, "industrial revolution"  - "Water-gas two-step manufacturing process"  Just entered the twenty-first century, mankind on the surprising discovery, accompanied by new technology, the arrival of a new Energy crisis of the red light The oil crisis, the coal crisis, gas crisis, a meeting to launch an attack, like a big hand扼住the blood of human China's energy in an emergency, an emergency energy in Western Europe, North America, the energy in an emergency, and for a time before a real energy problem before the The rise and fall of national energy, national survival, or even related to the survival of humanity as a To deal with energy issues, the EU issued a "security of energy supplies the EU Green Paper" "energy efficiency action plan", Japan enacted the "rationalization of energy use on the law" that "energy conservation law", "to promote the development of alternative energy sources of oil and import the relevant decrees, "that is" oil-alternative energy method ", the United States launched the" National Energy Policy Act - " China is also drafting the promulgation of the "Energy Law" and "Renewable Energy L" Some far-sighted entrepreneurs are timely development of new technologies, new "Two-step manufacturing process water gas" is gas-fired equipment in Luoyang of Henan for energy issues to deal with the new century and the development of environmental protection and energy saving It has high efficiency, energy saving, environmental protection and other In line with the party's "big 17" by the "energy-saving emission reduction efforts work, making efforts to promote resource-saving and environment-friendly society" required by a successful   Patented technology with the traditional process of comparison  Process gas two-step method (patent number: 4) is still using fixed-bed gasifier, the use of heated air to hair, high-temperature gas steam heat, and special jacketed boiler heat treatment; control gasification gas phase the most the lower part of the fuel ash is not temperature, not less than the transition of control of carbon and oxygen reaction temperature, the lower layer so as not to gasification of the carbon unburned gas temperature in the late resurgence to the following points to ensure that the entire cycle of the process of stable fire M In this way, two-step method only short briefing process gas and gas up the two processes, greatly simplifying the process to improve the strength of the single-furnace production, the elimination of the intermittent gas-step process of each switch sequence brought about by frequent high-and low-yield consumption, and to overcome the oxygen-rich gas required for the high cost of Two-step method for the uplink, only gas, furnace heat to bring out more through the air preheater, steam superheater and steam air preheater, heat recovery for reuse in this part of gas, so that heat loss will reduced to a minimum, but also increased the level of heating, and stability of the   Technology today is still widely used is the traditional five-step method, the process is: air hair, upstream gas, downstream gas, the second upstream gas, the air blowing cycle of the net five Because of the shared pipeline, and the realization of each stage depends on the valve control, valve switching frequency, occupied a great deal of time, resulting in lower gas Mainly in the upstream gas-phase gas in the gas production reached the maximum, as the bed temperature to drop rapidly in the gas phase down production of gas is lower than the average of most of the time; the second uplink gas main purpose is to security considerations, the air blowing the net mainly to the recovery stage gas furnace in the upper space and the gas Therefore the entire cycle gas intensity is not high, and low Multi-step cycle as a result difficult to achieve a short cycle of high-performance gas; gas phase lasted for a long time, heat absorption, and the whole cycle of ups and downs of temperature, the average low temperature, low vapor decomposition; At the same time, the turn of the entire multi-step cycle, an effective system of air time short, large heat loss; anti-jacketed wall of an increase of boiler design heat loss, and thus high energy consumption, coal consumption   Domestic small and medium-sized fertilizer plant now used mainly to suppress regular fixed-bed As the importance of environmental issues and the establishment of a conservation-minded society, there is a fixed-bed gas is difficult to The two-step process as a result of various measures taken to lower the temperature of the gas handling and cleaning: First, the use of heat exchangers for cooling and coarse dust, and then through the gas washing boxes, gas washing towers, desulphurization towers and packed tower for washing, desulfurization, naphthalene and off so that the cleanliness of gas production to satisfy the needs of, and comply with environmental protection and energy conservation   Two-step process of the new practice  Ruicheng County, Shanxi Pharmaceutical Packaging C, L is a new type of modern enterprise, with liquefied natural gas plant has been producing the past few years, as rising gas prices, increased product costs, competition in the market at a disadvantage, caught in a peacekeeping difficult In May 2006 the introduction of Luoyang of Henan coal gas equipment's advanced technology, has taken the lead in the use of water-gas two-step manufacturing process, and in July 2006 after the completion of installation to achieve the unexpected Equipment has not only brought huge economic benefits for enterprises, but also to fully verify the effective two-step process to solve the energy companies are facing the problem of emission   Two-step method of the advantages of new technology gas:  Reduce power consumption rate of a large  Ruicheng security in the bottle factory gas station coal consumption from 7 to 8 tons / day of gas production with the same legal system of the five gas installations 10 ~ 12 tons / day compared to nearly 30 percent drop in energy consumption; with more than two tons per day compared to gas, energy costs nearly 50%  2 Gas production stability, high heat value  Analysis of laboratory tests by the plant, gas heat value in 2800 ~ 2900 kcal / standard cubic   3 high-purity gas  Operation of the device produced by the gas to meet its production technology and the requirements of normal production, does not appear to plug the lamp is   4 simultaneous optimization effect  As a result of new technology produced a high calorific value gas, good stability and makes a number of business transformation projects to be implemented in order to bottle factory security as an example, the middle class to reach about 220,000, a growth rate of 20% and can achieve the non-basic operator As a result of low energy consumption, so that security costs have greatly lowered the production of bottles, so that enterprises find it difficult to survive out of the plight of the industry in the country Bottle On firmer   Analysis of the prospects for new technology  Today's China has become the coal, iron and steel, the world's largest copper-consuming country after the United States the world's second largest consumer of oil and electricity "Reuters News" reported that "Although oil and natural gas consumption increased rapidly, but the forecast at home and abroad by 2020, coal in primary energy consumption structure in China will continue to rank first, amounting to 60%" China Fan Weitang Coal Industry Association, the State Council Development Research Center of Energy-sponsored international seminar on strategies and policies, the current coal in primary energy consumption in China accounted for 67%, while the world average is 25% Process in the use of coal, there is a serious problem of environmental For this reason the Chinese government has introduced policies to support the development of clean coal Solve China's energy demand, improve energy efficiency in the development and utilization should in the first Energy conservation experts has been regarded as coal, oil, natural gas and electricity as important as the "fifth "  Luoyang, Henan coal-fired gas equipment companies original two-step water-gas production process, the rule of law to overcome the five gas carbon conversion rate is low and the chronic problem of low thermal efficiency, but also to overcome the fixed-bed oxygen-rich gas for the process of the high carbon dioxide levels, with very high economic efficiency and social efficiency benefits 2008/7/ Such as that used for transformation of the old plant, equipment changes to small, non-interrupted production, easy to An Ruicheng bottle factory gas station just over a hundred million to invest in a short period of time made tremendous achievements, is a good   New economic and social benefits of technology  The current national system of large and medium-sized fertilizer plants and plant more than 700, and 90% of the enterprises is still lagging behind the soon-to-be out of the five-step process gas Coal consumption of the process, and low productivity, low calorific value gas, low If the two-step method to introduce process gas or gas two-step method for the transformation process, it takes only from 6 to 10 million yuan, and does not interrupt production, easy to If every company of 500 tons of coal per day, and then under appropriate conditions to a minimum 18% rate of coal, then at least every enterprise can save more than 2000 million in energy consumption costs, the industry can save tens of billions of element of the energy Since 2003, high energy prices and by double-digit rate of non-stop climb, only 1-6 months in 2008 on coal prices rose 48 percent, to a huge coal production enterprises and economic pressure, which two-step process the rule of law brought about by gas will become more and more significant economic Conservation is profitable is to increase the competitiveness of saving, saving is a good concrete manifestation of the patriotic   Purely from the perspective of resources, China's coal resources according to an annual output of 5 billion tons of coal to supply projections are only 80 Seventeenth Party Congress explicitly put forward the building of environment-friendly society and resource-saving society, the concept of scientific Advances the development of resources for the sake of change the way the conversion of economic development path and model, to reverse the "high input, high consumption and high emissions, lack of coordination, difficult cycle and low-effectiveness" of the extensive mode of economic growth, and gradually establish a resource-saving industries systems and consumer Energy-saving and environmental protection has become a theme of the Henan Luoyang gas-fired equipment research and development of "two-step filling process the rule of law" to save its high performance and superior environmental performance totally fit the theme of this day and age is to work together towards the dawn of the If the process gas industry to promote, the entire gas industry in Europe and America close to or reach the advanced level of developed countries over the same Gas industry to the whole national economy as a whole new Gas two-step method of application and promotion process contains endless business 17 has a well-off society to achieve a higher goal and requirements of the responsibility of every entrepreneur, every ideal of a citizen should do their We look forward to two-step process to promote the rule of law gas early arrival of the

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首先google scholar网站收录论文的数量比其他数据库要多。其次该网站的很多论文可以直接在检索页面下载,不用进入论文网站。

Open access的文献是可以免费下载的。推荐Open Access 图书馆(oalib)。

Web of Science数据库是国际公认的反映科学研究水准的数据库,其中以SCIE、SSCI等引文索引数据库,JCR期刊引证报告和ESI基本科学指标享誉全球科技和教育界。检索精确到文献被收录的期刊、出版公司、作者、日期、页码等。seek68文献馆中外文献数据库汇集地,检索方便,涉及学科全面。文献下载成功率非常高。proquest博士论文全文ProQuest商业信息、学术研究、应用科技数据库。Sciencedirect: 荷兰Elsevier Science公司出版的期刊是世界上公认的高品位学术期刊,它拥有1263种电子全文期刊数据库,并已在清华大学图书馆设立镜像站点。FindaRticles是一个强大的能够获取免费出版文献的搜索引擎,它收集到的大部分文献都可免费阅读或打印全文,其中包括医学期刊。Open Access Library(OALib)图书馆让学者可以免费下载学术文献和论文,并在这个平台上发表自己的论文。Ingenta是目前世界最大的期刊数据库之一, 该库收录期刊已超过18,000种,拥有期刊文章索引(或文摘)7百多万篇,广泛覆盖了自然科学与社会科学多种学科的主题。德国施普林格(Springer-Verlag)是世界上著名的科技出版集团, 通过Springer LINK系统提供学术期刊及电子图书的在线服务。

CALIS学术会议论文库真的是强烈推荐这个,这个是我知道的比较全的了,虽然我本人不用,毕竟用不到,但我的老姐会用到。据我老姐的评论也是很好的。

查文献的外文网站

推荐OA图书馆,里面查到论文都可以免费下载。因为很多期刊为了提高被引率,都开始免费提供下载了。OA图书馆收集了这些资料,并制作了搜索引擎。你可以很方便的查到你想要的论文。都是学术性的论文,中英文的都可以查。推荐使用

掌桥科研,维普期刊等等。用的比较多的是掌桥科研。

查外文文献的网站

在文库里找

Springer,中国知网,万方数据库 等最好去大学的电子图书馆查,大学一般都购买了数据库,下载时是免费的

外国查文献的网站

查询国外学位论文的途径可使用PQDD-B(UMI博硕士论文数据库):可查询欧美1000余所大学1861年以来的160多万篇学位论文的信息,其中1997年以来的部分论文不但能看到文摘索引,还可以看到前24页的原文。另外总结了几个查找国外文献的途径,与大家分享,如果您有更好的查找方法,欢迎补充。一、x-mol直接在百度搜索x-mol,这里可以查找到很多文献,好多都是可以直接下载,即使无法下载,也可以看到其doi,复制其doi去百度学术、谷歌搜索、sci-hub、web of science之类的网站搜索即可。基本思想就是找文献的doi,然后下载。二、Already Have Keywords假如你已经拥有了你想要寻找的文献关键词,那么你可以直接进入谷歌学术、sci-hub、ProQuest等的网站直接搜索。三、Pay Attention to Foreign Universities最后,我们还可以关注国外综合类大学的硕博士毕业论文,比如普林斯顿、耶鲁、麻省理工、斯坦福、(加州)伯克利等等。不过在翻译硕博士论文时,由于硕博士论文篇幅太长,大家一定要做好论文阅读攻略,否则可能会耗时很久翻译一篇文章,但结果却事与愿违。

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