外文翻译-中英文-冲天炉炼铁

外文翻译-中英文-冲天炉炼铁 毕业设计外文翻译 题 快递公司问题件快递公司问题件货款处理关于圆的周长面积重点题型关于解方程组的题及答案关于南海问题 目:Iron making in a cupola 冲天炉炼铁 学生姓名: 学 号: 专 业: 班 级: 指导教师 : Iron making in a cupola J.E. Rehder , President, Metkem Processes Ltd, Toronto ,Canada IT is well known that iron can be made by heating pellets of mixed iron ore and carbon. .There are considerable attractions to this procedure including the use of ore fines or dusts ,low-cost reduction carbon and possibility of operating economically at moderate rates of 50,000 to 300,000 ton/year .Various attempts have ,therefore ,been made to find a commercially successful route .Outlined here are the problem and a solution that is working very well at pilot plant scale . Metallurgy The basic procedure is to make a compact of finely divided iron oxide with enough carbon to completely reduce the oxide to metal ,and then to heat this compact until reaction is complete . Two course of action ,which have different results ,are possible . One is to heat the ore-carbon compacts to somewhat below their fusion point ,to make a product of solid state reduced iron mixed with gangue and carbon ash .This can be done in a rotary kiln ,on a traveling grate or in a vertical shaft furnace ,and considerable development work has been done on the first two methods .The product can be used as blast furnace feed or can be melted and refined to steel in an arc furnace .However ,it is now clear that use of reduced pellets as blast furnace feed does not give the best economics ,and melting refining of steel must contend with the added slag volume and sulfur brought in with the reduction carbon . The other course is to heat ore-carbon pellets to and through the fusion points of iron and gangue ,to produce hot metal and molten slag .This can and has been done in an arc furnace and in an induction furnace ,but the most economical way is in a fuel fired shaft furnace .The best known such furnace is a cupola ,such as is used in iron foundries .When ore-carbon pellets are charged to a cupola that is being operated under the right conditions ,hot metal and slag are readily produced and tapped with excellent recovery .This has been successfully done during a development program ,and at one stage a lean ore that produced 2 ton of slag/ton of hot metal was 1 satisfactorily handled .Scrap iron or steel is readily incorporated in the charge .The hot metal produced can be used directly in an iron foundry or converted to steel . The cupola At this point a clear distinction must be made between a cupola and a blast furnace .One is not a small or large version of the other since the modes of operation and internal conditions are quite different .In normal practice the cupola is operated solely as a heat generator to melt solid charge material ,whether iron ,bronze or stone ,and it does this with the highest thermal efficiency of any widely-used fuel-fired melting furnace .Fuel coke is burned under condition to create the maximum carbon dioxide content consistent with low oxidation losses of iron and alloys .This is normally 11 to 13% and means that more than in the blast furnace .The top gas is lean but is ample in heat content to recuperatively heat combustion air to the moderate degree required . When ore-carbon pellets are charged to a cupola ,a considerable amounts of carbon monoxide is generated from the reduction reactions and enriches the top gas .The top gas also is higher in volume due to the combustion of the increased amount of coke to supply large heat of reaction .The net result is 70,000 to 80,000 cu ft of top gas/ton of hot metal containing 25 to 30%carbon monoxide ,which gives a surplus after blast heating of about 5 MM Btu/ton of hot metal . Stock column height is relatively low ,20 to 50 ft ,and residence time is 1.0 to 1.5 hr . Blowing rate in cfm/sp ft of shaft cross section is about double that in the blast furnace ,but pressure is lower due to the shorter stock column and a higher permeability .Production rates of 4 to 5 ton of hot metal/sq ft /day appear practical .At this stage it is not known how large the cupola can be effective in this manner .The largest existing iron melting cupola is 12.5ft ID which could represent 600 ton of hot metal/day as smelter ,but there is evidence of a dead-man and some question as to whether the cupola mode of combustion can be maintained in this or larger cupolas . Due to lower blast pressure the cupola operated as a smelter can be tapped continuously through a siphon if desired .The cupola is also readily externally water cooled in the high temperature zone ,and is easily shut down for repair after a 3to 2 5-week campaign .These and other factors indicate that for example ,600 ton of hot metal/day would be more practically obtained from two 8.8 –ft dia cupolas than from one of 12.5 ft dia . Hot blast and oxygen enrichment Use of hot blast saves coke in linear proportion to air temperature and also increases production rate ,but in iron melting practice about 1200F(649C) is the maximum used .This is primarily due to the cost of higher temperature air heating equipment ,but at every high air temperature there is evidence of lower combustion efficiency tuyeres .The maximum economical air temperature for the smelting mode of operation is not presently known . Oxygen enrichment of combustion air is effective in decreasing coke consumption in iron melting and in smelting .The economy ,of course ,depend on local prices of oxygen and of coke . Both hot blast and oxygen enrichment are effective through increase in flame (i .e ,maximum bed )temperature ,and this is subject to different constraints in the cupola and in the blast furnace .The production of increased reducing gas by using tuyere injected fuel is useless in the cupola ,since the objective is a combination of maximum bed temperature with maximum heat production . Agglomeration Strength requirement of ore-carbon compacts for a cupola are much less severe than for blast furnace pellets ,since the stock column is shorter and in many cases the compacts can be made at the cupola site so that handling is minimal . Pelletizing , extrusion and briquetting have all been used ,and binders are carbonates ,silicates or asphalt .The principal limitation is that the compacts ,of course ,cannot be heated for hardening above the ignition temperature of the contained carbon ,unless autoclaved .There are several systems available and these will not be reviewed here . Economics and uses There is no question that smelting of ore-carbon compacts in a cupola is not expected to be economically competitive with the blast furnace ,or to operate in or 3 near its production rates and size ranges .However ,there does seem to be a place for moderate tonnages in suitable supply situations. Ore-supply Supply of iron ore fines can be an economic problem since the iron ore industry is organized to provide pellets or lump ore in large quantity ,and obtaining 150,000ton/year of clean concentrate for example could encounter high freight costs .Mill wastes ,such as blast furnace dust and mill scale ,can ,however ,be readily handled and are in reasonable quantity .There is basis for thinking that such wastes can be turned into hot metal at lower capital and operating cost in the cupola ,than by processing over a sinter strand and through a blast furnace .An added factor here is that volatile elements ,such as zinc ,should be more readily handled in the cupola than in the blast furnace . Coke It is essential to the economy of cupola operation to use coke of reasonable large lump size ,this being one of several differences from blast furnace operation . If a cupola is used to smelt mill wastes in or near a steel plant ,the economic course is to use the oversize coke from the coke plant primary screen or grizzly ,since this avoids the cost of crushing to blast furnace size ,and the production of hot metal/ton of coke is higher than from a blast furnace . If the cupola is used separately from a steel plant and such coke is not available ,foundry coke must be used but at considerably higher price .Lump anthracite can be used to replace a portion of the coke charge ,and briquetted calcined petroleum coke is an excellent cupola fuel . Reduction carbon The desirable properties of the carbon to be mixed with the ore are high fixed carbon content ,good reactivity ,and low sulfur ash and volatile matter contents .These can be met by a considerable variety of relatively low cost carbons ,and this is a principle reason for good economics in smelting ore-carbon compacts in the cupola .The total fixed carbon required/ton of hot metal will be in the order of 1250 to 1500 1b, but 40 to 45%of this does not require to be coked or coke able . 4 Uses There are three areas where cupola mode smelting can be economically interesting .These are treating mill oxide wastes ,providing hot metal for direct use in iron foundries and for mini steel mills based on small oxygen vessels . Processing of mill wastes is immediately interesting because of the ready supply of raw materials ,there is activity in more than one location in developing this route .The cost advantage will ,of course ,vary with local conditions ,such as whether an existing sinter plant is overloaded ,worn out or requiring extensive new air pollution control . Hot metal for medium size and large iron foundries can show every good economics from iron ore ,the main uncertainly at the present time being the availability and cost of iron ore fines .This depends on location and on the interest of iron ore suppliers in such a market .There would appear to be opportunity for a considerable independent business in the manufacture and sale of ore-carbon pellets or compacts . Operation of a mini steel mill or an oxygen vessel supplied by hot metal from a cupola can be economic depending on local prices .A feasibility study on a 300,000 ton/year mill using a 35-ton vessel showed very good costs .An added considerable advantage is the ability to incorporate steel scrap in the cupola charge ,giving valuable flexibility in raw materials . Summary The above outline of what can be done in smelting ore-carbon compacts in a cupola mode shaft furnace ,indicates that hot metal can be made economically in moderate volume from a variety of iron oxide sources .The equipment involved is well developed and is appreciably lower in unit cost than an equivalent blast furnace .There is considerable activity in the field and the prognosis appears good . 5 冲天炉炼铁 众所周知的，可以通过加热球团状的铁矿石和焦碳混合坯块来炼铁。现在有一种很有吸引力的炼铁 方法 快递客服问题件处理详细方法山木方法pdf计算方法pdf华与华方法下载八字理论方法下载 ，就是通过使用粉矿或者粉末等低成本的碳在可能的范围里稳步的使经济比率从50，000提高到300，000吨每年。因此，已经尝试各种途径去寻找一种能够成功运行的商业路线。简单的说下面是问题和解决问题的 答案 八年级地理上册填图题岩土工程勘察试题省略号的作用及举例应急救援安全知识车间5s试题及答案 ，在实验厂里的工作非常好的一种方法。 冶金 最基本的方法就是制造一个能使氧化铁和足够的焦碳合理的混合的坯块，从而使氧化铁降低氧化物从而得到金属，然后加热这个小坯块直到反应结束。有两种方法是可以实现的，这两种方法会出现不同的结果。 一种方法是加热矿石碳坯块到稍微低于它们的熔点温度，这样就获得一种混有矿渣和碳灰的固态还原铁。这个可以用回转炉,转动炉排或者竖式燃烧炉来完成,可观的试制工作已经开始做前两种方法。这种产品可以用着高炉炉料，还可 然而，现在 表 关于同志近三年现实表现材料材料类招标技术评分表图表与交易pdf视力表打印pdf用图表说话 pdf 明把这种还原球状颗粒当高炉炉料用并不以通过电弧炉提纯到钢。 能有最好的经济效应，同时，熔化状的钢提纯时，要考虑炉渣量的增加，硫和碳的含量降低等问题。 另外一种方法是加热球团状的矿石和焦碳使其通过铁和矿渣的熔点，从而得到液态金属和液态矿渣。这个能够并且已经在电弧炉和感应电炉上应用，但是最经济的方法是在燃料火竖炉上的应用。众所周知的这样的熔炉是一种冲天炉，就象现在许多铸铁厂用的。当球团状的矿石和焦碳被送进冲天炉时，正是它们发生反应的良好环境，液态金属和矿渣很容易的就产生了，同时加以很好的回收利用。这个已经在一个发展项目里成功完成，在这一阶段，低品位矿可以产生2吨矿渣和1吨热金属，是一种另人满意的处理。废铁或者钢轻易的被并如到原料里。液态金属可以直接用在铸铁厂或者去炼钢。 冲天炉 在这点上必须对冲天炉和炼铁高炉有明显的区别。这并不是一个和另一个大小的区别，而是它们工作方式和内部环境有着很大的区别。在正常的情况下，冲 6 天炉就象热风炉那样单独操作来熔化固体炉料，无论是铁，青铜或者是石头，它是现在广泛使用的各种燃料火熔融炉中热效率最高的。焦碳在合理的控制下燃烧以便产生最大量的二氧化碳，同时保证很小的铁和混合物的氧化损失。这个正常的是11%到13%，远远超过在炼铁高炉。高炉煤气虽然有点少，但富含热量可以稳定的满足中等强度的加热燃烧空气。 球团状的铁矿石和焦碳装入冲天炉，便能从还原反应和丰富的高炉煤气中产生相当可观数量的一氧化碳。高炉煤气在体积方面也很大，这是由于为了供应大量的反应热而不断的燃烧增加的焦碳产生的。最后的结果就是70，000到80，000立方英尺的高炉煤气每吨热金属里包含大约25%到30%的一氧化碳，通过热鼓风炉后就剩下不到5mm btu(英制单位)每吨热金属。 冲天炉的相对高度比炼铁高炉低20到50 英寸，同时停留时间是1.0到1.5hr每立方英尺/分/空间英尺的轴截面上鼓风量是炼铁高炉的两倍，但是较低的料柱和较高的透气性导致压力降低。生产率实际上大致是每天每平方米产4到5吨热金属。用这种方式计算还不知道多大的冲天炉才有实际效益。作为熔炉，现在最大的铁水冲天炉是内径为12.5英尺的，每天能产生600吨热金属，但是有些问题是冲天炉的燃烧方式能否维持到这个或者更大容量的冲天炉。 作为熔炉，由于鼓风压力的下降，冲天炉可以连续不断分别通过一个弯管，如果有这样的要求的话。在冲天炉上可以很容易的实现外部水冷，在3到5星期的炉期后，由于修理需要关闭时也很容易实现。这些以及其它因素表明，例如，每天要产生600顿热金属时，两个8.8英尺的冲天炉在实际应用中比一个12.5英尺的更容易获得。 热风和富氧 使用热风可以节省焦碳，提高生产率，但是在铁水冶炼过程中最大的使用量是1200F(649C)。 这个主要是由于高温空气用于加热设备了，但是也有证据表明高层温度是由于较低的鼓风口燃烧效率。在不同的冶炼方式最大的经济气温目前还不清楚。 在铁水冶炼过程中富氧空气燃烧减少焦碳的使用量。它的经济性决定于当地的氧和焦煤的价格比。 热风和富养在实际应用中都是通过增高火焰温度，但它们在冲天炉和炼铁高 7 炉是具有不同的限制条件的。在冲天炉中，通过在鼓风口喷吹还原气体来增加产量是没有用的，因为在冲天炉中产生最大的炉床温度同时伴有大量的热是主要目标。 烧结 冲天炉对碳和矿石坯块的强度要求没有炼铁高炉要求的严格，主要是因为料柱比较低，同时由于坯块的生产都在冲天炉附近，处理比较少。 烧结时使用的方法有粒化，挤出，以及压块，使用的粘合剂是碳酸盐，硅酸盐或者柏油。最大的限制条件就是压块能否在高于碳的燃烧温度加热变硬，除非在压热器中才能实现。有几种方法是可以利用的，在这里就不加于评论了。 经济效益和使用情况 在经济效益和生产规模方面冲天炉冶炼碳矿石坯块是不能和炼铁炉冶炼相比的。但是，在中等吨位的冶炼，以及在适当的地方还是比较适合使用冲天炉冶炼的。 矿石供给 铁矿的供给可以说是一个经济性的问题，因为铁矿工业是一个提供颗粒或者块状矿石的产业，每年需要150，000吨的精矿，还有很高的运输费用。象高炉灰和轧粉这样的磨料浪费可以轻易的处理，并且数量很大。把那些浪费转化成热金属是冲天炉的基本事情，并且与使用带式烧结机或者炼铁高炉相比，具有较低的资本和操作费用。这里还有一点是，象锌这种容易挥发性元属在冲天炉里比在炼铁炉更容易处理。 焦碳 使用大块状的焦碳是冲天炉操作不可缺少的一部分，这也是冲天炉操作和炼铁高炉操作几个不同点之一。如果冲天炉用做处理磨细的粉屑浪费或者作为炼钢厂，那么比较经济的办法是使用炼焦厂的一次筛或者是铁格筛下的大块焦碳，因为这样可以减少把焦碳压成炼铁高炉所使用的的规格的费用，并且每吨焦碳产生的热金属比炼铁高炉高。 如果冲天炉用在炼钢厂和焦碳分开的地方，焦碳也是必须用的但是价格比较高。块状无烟煤可以替代部分焦批，煤饼，锻烧石油焦也是极好的冲天炉燃料。 碳还原 8 在碳和铁矿石的混合物中的凝固碳里有许多可取物质，具有很强的反应能力，它们具有低硫性，以及很强的挥发性。这些物质可以看作是低成本的碳，这也是冲天炉冶炼碳矿石坯块具有很强的经济性的原因。产生每吨热金属大约需要1200到1500b的这种凝固碳，这里40%到50%是焦碳做的。 使用 冲天炉熔炼在以下三个方面应用是有很好的经济效益的。他们是处理磨料浪费，直接用于铸造和小规模的氧气炼钢。 处理磨料浪费是最具有直接经济效益的，因为原料都是准备好的，在这方面的应用已经不只在一个场所使用。处理废料的优势是随当地的具体情况而不同的，就象当地的烧结厂过量时，就会出台新的空气污染控制来加以控制。 从铁矿石里熔炼热金属用于中等或者较大点的铁铸造是具有比较好的经济效益的，现在最主要的不确定的因素就是可行性和铁矿粉末的费用。这个决定于地点和市场上铁矿石供应着的利润。这显示出将生产矿石碳球团或者坯块作为一个是独立的行业是一个时机。 通过冲天炉冶炼热金属来经营一个较小规模的炼钢厂或者氧气转炉炼钢的经济效益取决于当地价格。一个关于可行性研究表明用一个35吨的氧气转炉来供应一个每年300，000吨每年的轧机具有很好的价值。还有一个很重要的优势是可以把废钢直接作为原料放入冲天炉，给冲天炉提供很重要的柔性原料。 总结 初级经济法重点总结下载党员个人总结TXt高中句型全总结.doc高中句型全总结.doc理论力学知识点总结pdf 上述表明通过冲天炉冶炼碳矿石坯块可以作为中等容量氧化铁的来源。这套设备是很有发展前途的，生产相同容量下的热金属比炼铁高炉成本要低。在这方面是有竞争力的，呈现出较好的前景。 9