1、and solve this problem. He knew that cholera would never be controlled until its cause was found.He became interested in two theories that possibly explained how cholera killed people. The first suggested that cholera multiplied in the air. A cloud of dangerous gas floated around until it found its
2、victims. The second suggested that people absorbed this disease into their bodies with their meals. From the stomach the disease quickly attacked the body and soon the affected person died.John Snow suspected that the second theory was correct but he needed evidence. So when another outbreak hit Lon
3、don in 1845, he was ready to begin his enquiry. As the disease spread quickly through poor neighborhoods, he began to gather information. In two particular streets, the cholera outbreak was so severe that more than 500 people died in ten days. He was determined to find out why. First he marked on a
4、map the exact places where all the dead people had lived. This gave him a valuable clue about the cause of the disease. Many of the deaths were near the water pump in Broad Street (especially numbers 16,37, 38 and 40) . He also noticed that some houses (such as 20 and 21 Broad Street and 8 and 9 Cam
5、bridge Street) had had no deaths. He had not foreseen this, so he made further investigations. He discovered that these people worked in the pub at 7 Cambridge Street. They had been given free beer and so had not drunk the water from the pump. It seemed that the water was to blame.Next, John Snow lo
6、oked into the source of the water for these two streets. He found that it came from the river polluted by the dirty water from London. He immediately told the astonished people in Broad Street to remove the handle from the pump so that it could not be used. Soon afterwards the disease slowed down. H
7、e had shown that cholera was spread by germs and not in a cloud of gas.In another part of London, he found supporting evidence from two other deaths that were linked to the Broad Street outbreak. A woman, who had moved away from Broad Street, liked the water from the pump so much that she had it del
8、ivered to her house every day. Both she and her daughter died of cholera after drinking the water. With this extra evidence John Snow was able to announce with certainty that polluted water carried the virus.To prevent this from happening again, John Snow suggested that the source of all the water s
9、upplies be examined. The water companies were instructed not to expose people to polluted water any more. Finally “King Cholera” was defeated. COPERNICUS REVOLUTIONARY THEORYNicolaus Copernicus was frightened and his mind was confused. Although he had tried to ignore them, all his mathematical calcu
10、lations led to the same conclusion: that the earth was not the centre of the solar system. Only if you put the sun there did the movements of the other planets in the sky make sense. Yet he could not tell anyone about his theory as the powerful Christian Church would have punished him for even sugge
11、sting such an idea. They believed God had made the world and for that reason the earth was special and must be the centre of the solar system.The problem arose because astronomers had noticed that some planets in the sky seemed to stop, move backward and then go forward in the loop. Others appeared
12、brighter at times and less bright at others. This was very strange if the earth was the centre of the solar system and all planets went round it.Copernicus had thought long and hard about these problems and tried to find an answer. He had collected observations of the stars and used all his mathemat
13、ical knowledge to explain them. But only his new theory could do that. So between 1510 and 1514 he worked on it, gradually improving his theory until he felt it was complete.In 1514 he showed it privately to his friends. The changes he made to the old theory were revolutionary. He placed a fixed sun
14、 at the centre of the solar system with the planets going round it and only the moon still going round the earth. He also suggested that the earth was spinning as it went round the sun and this explained changes in the movement of the planets and in the brightness of the stars. His friends were enth
15、usiastic and encouraged him to publish his ideas, but Copernicus was cautious. He did not want to be attacked by the Christian Church, so he only published it as he lay dying in 1543.Certainly he was right to be careful. The Christian Church rejected his theory, saying it was against Gods idea and p
16、eople who supported it would be attacked. Yet Copernicus theory is now the basis on which all our ideas of the universe are built. His theory replaced the Christian idea of gravity, which said things tell to earth because God created the earth as the centre of the universe. Copernicus showed this wa
17、s obviously wrong. Now people can see that there is a direct link between his theory and the work of Isaac Newton, Albert Einstein and Stephen Hawking.Unit 2 PUZZLES IN GEOGRAPHYPeople many wonder why different words are used to describe these four countries: England, Wales, Scotland and Northern Ir
18、eland. You can clarify this question if you study British history.First there was England. Wales was linked to it in the thirteenth century. Now when people refer to England you find Wales included as well. Next England and Wales were joined to Scotland in the seventeenth century and the name was ch
19、anged to “Great Britain”. Happily this was accomplished without conflict when King James of Scotland became King of England and Wales as well. Finally the English government tried in the early twentieth century to form the United Kingdom by getting Ireland connected in the same peaceful way. However
20、, the southern part of Ireland was unwilling and broke away to form its own government. So only Northern Ireland joined with England, Wales and Scotland to become the United Kingdom and this was shown to the world in a new flag called the Union Jack.To their credit the four countries do work togethe
21、r in some areas(eg, the currency and international relations), but they still have very different institutions. For example, Northern Ireland, England and Scotland have different educational and legal systems as well as different football teams for competitions like the World Cup!England is the larg
22、est of the four countries, and for convenience it is divided roughly into three zones. The zone nearest France is called the South of England, the middle zone is called the Midlands and the one nearest to Scotland is known as the North. You find most of the population settled in the south, but most
23、of the industrial cities in the Midlands and the North of England. Although, nationwide, these cities are not as large as those in China, they have world-famous football teams and some of them even have two! It is a pity that the industrial cities built in the nineteenth century do not attract visit
24、ors. For historical architecture you have to go to older but smaller towns built by the Romans. There you will find out more about British history and culture.The greatest historical treasure of all is London with its museums, art collections, theatres, parks and buildings. It is the centre of natio
25、nal government and its administration. It has the oldest port built by the Romans in the first century AD, the oldest building begun by the Anglo-Saxons in the 106os and the oldest castle constructed by later Norman rulers in 1066. There have been four sets of invaders of England. The first invaders
26、, the Romans, left their towns and roads. The second, the Anglo-Saxon, left their language and their government. The third, the Vikings, influenced the vocabulary and place-names年产5万吨氯化法钛白粉工程项目建议书二六年十二月第一章 总 论1.1项目名称、建设单位、企业法人及项目负责人1.1.1项目名称:年产5万吨氯化法钛白粉工程1.1.2建设单位:*总公司1.1.3企业法人:*1.1.4项目负责人:*1.2企业概况*
27、总公司公司采用国内外先进的生产技术,建成了年产1.5万吨硫酸法钛白粉装置,成为国内目前最大的钛白生产装置之一。该装置生产的锐钛型 BA0101 钛白粉,是一种优质白色原料,化学性质稳定,粒子细小均匀,光学性能佳,着色力高,广泛应用于涂料、橡胶、造纸、塑料、油墨等行业,产品畅销全国 20 多个省市。1.3项目提出的背景、投资必要性和意义钛白粉化学名称为二氧化钛,它具有较高的化学稳定性、耐热性、耐候性,良好的白度、着色力和遮盖力,是最重要的无机颜料和化工原料。颜料级钛白粉主要应用于涂料、造纸、塑料、橡胶、印刷油墨、化学纤维等行业,非颜料级钛白粉主要应用于搪瓷、电容器、电焊条等。 颜料级钛白粉分锐钛
28、型和金红石型两类,金红石型产品在性能上优于锐钛型,因而得到更为广泛的应用。由于钛白粉的应用领域不断扩展,对产品性能不断提出新的要求,众多的品种应运而生。据前几年不完全统计,全球市场上先后出现的钛白粉牌号多达600个,其中用于涂料的为375个,占总数的62.5。在375个涂料用牌号中,金红石占77,锐钛型占23。但在国外涂料工业实际应用中,锐钛型钛白粉数量很少,不足,而经过表面处理的金红石型钛白粉占99。 钛白粉工业生产方法有硫酸法和氯化法。硫酸法可生产锐钛型和金红石型两种产品,氯化法只能生产高档的金红石型产品。与国外先进水平相比,我国钛白粉工业存在生产技术落后、生产规模小、原料品位低和产品质量
29、不稳定等差距。在生产技术上,国外以氯化法为主,而我国基本上都是硫酸法生产。即使是硫酸法,我国大部分厂家在工艺技术、生产装备、自控监测、 “三废”治理等方面与国外也有很大差距。在生产规模上,国外钛白粉装置平均规模为年产6万吨,其中氯化法最大为30.5万吨,硫酸法为13.1万吨。而我国钛白粉生产装置平均规模仅为4000吨,最大的也仅为1.5万吨。生产规模小,造成了能耗高和生产成本高,也导致产品质量不稳定。在原料方面,国外硫酸法大都采用高品位酸溶性钛渣,而国内基本上直接使用钛铁矿。资源的品位低也影响了钛白粉产品质量。在产品质量上,国外以光学性能好和遮盖力、消色力、耐候性优异的金红石型钛白粉为主,其中
30、又以经过表面处理的金红石型钛白粉居多,并有各种专用钛白粉产品。国内硫酸法钛白粉以锐钛型产品为主,大部分未经过表面处理,专用产品极少。国产钛白粉白度差、消色力低、研磨分散性差,难以满足涂料、油墨、塑料、橡胶等行业的要求,大多只适用于造纸、化纤、搪瓷等生产。我国钛资源十分丰富,但钛白工业却相对落后。目前全国钛白粉人均消费量不足0.3千克,仅相当于北美地区的二十分之一,西欧的十分之一。随着国内经济的发展,人民生活水平的不断提高,尤其是人们环保意识的觉醒和对提高生活档次的追求,钛白粉的消费量将快速递增,国内钛白粉行业在产品质量档次方面距市场差距十分突出。2000年全国钛白总产量约29万吨,其中金红石型
31、产品仅5万吨左右,2001年全国钛白总产量达33万吨,其中金红石型产品仅5.7万吨。为满足国内市场对高档金红石型钛白的需求,2000年进口了14.6万吨,2001年进口15.5万吨,花费了大量外汇。以2000年为例,钛白粉57%用于涂料,22%用于塑料,12%用于造纸,其它行业占9%。塑料行业已取代造纸行业,成为钛白粉第二大用户,并且是未来增长最快,最有活力的行业。市场对钛白粉的需求结构,因此而产生重大影响。这些行业在国内主要集中在华东和华北地区,因此我国钛白粉消费的主体市场为华东和华北地区。我公司地处鲁北,位于华东和华北地区腹地,地理位置优越,市场前景广阔。我国唯一的氯化法钛白粉生产线(即攀
32、钢集团锦州钛业有限公司年产1.5万吨CR501金红石型氯化法钛白粉)已达产至设计生产能力,并通过国家投产鉴定,宣告了我国已经全部掌握了氯化法生产钛白粉的复杂工艺。因此,我公司开发建设年产5万吨氯化法钛白粉工程可依托国内技术。综上所述,*总公司依托自身的资源、技术、人才、市场等优势,建设年产5万吨氯化法钛白粉装置,对提高我国钛白粉行业规模、技术装备水平,扩大高档金红石型钛白生产能力,缓解国内市场高档钛白供应的紧张状况、替代进口产品、节省国家外汇,将具有重要的现实意义。第二章 市场分析2.1国际市场分析二氧化钛消费需求量与全球经济发展息息相关。50年代的二战后重建,使钛白粉的需求量剧增,每年以约7
33、%的速度增长,50年代末消费量达90多万吨。60年代发展较平缓,以约6%的速度增长。进入70年代,受两次石油危机的影响,其需求量大大下降,到70年代末,还不到200万吨。80年代,二氧化钛工业第一个发展期到来。1982-1989年,由于几家大二氧化钛生产厂的关闭及全球需求量的急剧增长(最高年增长率为8%),到1989年需求量达300多万吨。钛白粉市场出现供不应求的局面,每吨价格高涨到2900美元。1990年市场需求量突然下降5%,跌到290万吨。1991年、1992年继续走低,1993年才有所上升。与此同时,有6家二氧化钛厂(总产能约35万吨)陆续投产,产量的增长进一步加剧了供大于求的趋势。1
34、994年,需求量回升到340万吨。1995-1996年消费需求量仍保持在这一水平,但价格下跌严重,最低时只有1500美元/吨。从1997年初开始,全球二氧化钛工业缓慢复苏,市场需求量恢复到360多万吨,进入第二个发展期。1998-1999年末上升势头很明显。每吨价格也涨到2100美元。2000年更一跃到2300美元左右,且出现供不应求局面。因全球经济的复苏和涂料、塑料、油墨等相关行业需求的激增,估计这一轮增长还将持续一段时间。2.2国内市场现状随着我国国内经济的快速发展,国家增加投资、实施扩大内需的政策,促使了以城镇居民为对象的房地产市场升温,推动了涂料工业的发展,加上塑料、造纸等行业用量增加
35、,2002年国内总消耗量50万吨,其中进口高档钛白粉16万吨,出口锐钛型钛白粉6万吨,国内实际产量40万吨。我国钛白粉生产市场情况如下:(1) 国内钛白粉产量与需求量实现迅速增长(见表2-1)表2-1 钛白粉的国内表观消费量与产量变化情况年 份1985年1990年1994年2000年2002年产量(万吨)3.226.377.8128.9240.00表观消费量(万吨)5.016.7811.2737.5650.00(2) 产能极度分散,规模极不经济虽然国内年产钛白粉量达40万吨,但由56家企业生产,最大产能不超过2.5万吨(最大产量不超过1.8万吨),最小的近1000余吨,即没有达到经济规模的企业
36、,也没有达到经济规模的生产线。(3)钛白粉档次低,品种结构不合理与进口的同类钛白粉相比,国产钛白粉的质量均属于中档水平,国产钛白粉中又以锐钛型钛白粉产量占绝对主导,而国内市场量大、盈利能力强的却是金红石产品。表2-2 国产钛白粉品种结构情况表项 目金红石涂料级锐钛型搪瓷级锐钛型合 计30个主要钛白企业产量(万吨)7.519.03.029.5其余26个钛白企业产量(万吨)0.09.02.011.0合计(万吨)7.528.05.040.5各品种所占比例(%)17.570.012.5注:以2002年上半年生产数据为基础分析。(4) 国内钛白粉行业竞争结构国产钛白粉因质量原因难以进入国内高档次钛白粉市
37、场,高档市场基本被世界前七位生产商垄断。国内中档市场由国内部分钛白粉企业与国外中型钛白粉企业展开竞争,以国内为主;国内低档市场由国内钛白企业供应。表2-3 国内钛白粉市场竞争结构表钛白粉种类档次主要供应商金红石钛白粉高档杜邦公司、美礼联公司、科美基公司、克朗诺斯公司、日本石原、亨兹曼、凯米拉公司中档攀钢、锦州、渝钛白、四零四等国内企业与国外部分钛白企业锐钛型钛白粉高档日本石原、萨奇宾中档国外中型钛白粉企业与国内攀钢钛业、济南裕兴、镇钛等企业(4) 进出口情况进口绝对量保持快速增长,进口总量占国内表观消费的35%以上;出口以低挡钛白粉为主,出口绝对量增长缓慢并占国内产量的比例呈现下降趋势。表2-
38、4 国内进出口钛白粉情况项 目1990年1994年2000年2002年进口情况分析进口钛白粉量(万吨)2.355.4114.1916.00占国内消费量的比例(%)46.9136.6737.7736.22出口情况分析出口钛白粉量(万吨)1.41.95.66.0占国内产量的比例(%)21.924.419.415.0出口钛白粉的品种结构(以2002年上半年数据为依据分析)国产金红石涂料级锐钛型搪瓷级锐钛型合计出口钛白粉数量(吨)20.5415158361120823比例(%)10.072.717.3100.0第三章 建设规模及内容3.1 建设规模年产5万吨氯化法钛白粉工程3.2 建设内容本项目建设内
39、容主要包括四氯化钛的制备及精制(氯化)、四氯化钛的氧化(氧化)、二氧化钛的表面处理(后处理)三大工段。(1)四氯化钛的制备及精制工段包括:原料粉磨、氯化、分离、冷凝、除钒、蒸馏、蒸发、尾气的分离与净化等主要工序。(2)四氯化钛的氧化工段包括:预热、氧化、骤冷、分离、氯气回收等主要工序。(3)二氧化钛的表面处理工段包括:打浆、研磨、化学品制备、表面处理、过滤洗涤、喷雾干燥、微粉碎及成品包装等主要工序。3.3产品质量标准产品设计目标为通用型金红石型颜料级二氧化钛,质量指标可按中国国家标准GB1706-93或国际标准ISO591-1995生产,并可达到杜邦R902的产品质量标准,具体可按用户要求生产
40、。中国国家标准GB1706-93、国际标准ISO591-1995、杜邦R902的金红石型钛白粉技术指标分列如下: 表3-1 金红石钛白粉中国国家标准GB/T1706-93、国际标准ISO591-1977、杜邦R-902的质量标准对照表标 准GB/T1706-93ISO591-1977R-902BA01-03B类优等品一等品合格品R1R2R3TiO2含量/% 98929097908091颜色(与标样比)近似不低于微差接近商定样品98.5消色力(与标样比)/%10010090与商定样品相同105挥发分/% 1.01.01.00.5商定经232及相对湿度(505)预处理24h后105挥发物/% 1.
41、51.51.00.51.52.5水溶物/% 0.30.30.50.60.50.7水悬浮液 PH值6.56.66.6与商定样品相同8.7吸油量/(g/100g)8.08.08.5与商定样品相同17.0筛余物(45m筛余)/%2023260.100.10水萃取液电导率1005050与商定样品相同Al2O3典型含量/%SiO2典型含量/%相对密度4.0中位数粒径/m0.32最低电阻/K4.0炭黑底色11.5有机处理剂(以碳计)根据用户需要第四章 工艺技术方案4.1 工艺技术方案的选择目前,世界上二氧化钛的工业生产方法主要有硫酸法和氯化法两种。硫酸法是以钛铁矿为原料,通过硫酸使钛铁矿分解,钛铁矿中的T
42、iO2分解成TiOSO4,过滤除去钛液中的不溶矿物质,然后通过真空结晶除去钛液中的七水硫酸亚铁。钛液经水解变成TiO2H2O,洗涤除去其它矿物质产生的盐类,经煅烧除去水分并使其晶型转化制得。该法对原料品位要求不高,矿源丰富,价廉易得,但工艺流程长,“三废”排放较多。氯化法对于硫酸法而言是一个技术进步,是以金红石或高钛渣为原料,经氯化生产四氯化钛,然后在高温下氧化而制得。该方法生产流程短、产品质量好、可实现生产的连续化和自动化、氯气可循环利用、“三废”排放少,但对原料的品位要求高、技术复杂、对设备材质的要求高。国内目前几乎全都是采用硫酸法生产,氯化法工业化生产仅有攀钢集团锦州钛业有限公司一家;国
43、际上氯化法生产工艺已占主导地位,占世界总产能的58%;硫酸法生产工艺仅占世界总产能的42%,并有减少趋势。综上所述,本项目拟采用先进的氯化法生产工艺生产高档金红石型钛白粉。4.2 工艺流程简述*总公司年产5万吨氯化法钛白粉工程的流程示意图见图4-1,流程大致分三部分:氯化工段、氧化工段和后处理工段。4.2.1氯化工段主要设备是沸腾氯化炉,通常用钢制成,衬有耐火材料并罩有外部水冷套。金红石矿或高钛渣等富钛料经粉磨后,与一定比例的石油焦从沸腾层上方加入沸腾炉,从氧化工序返回的循环氯气从炉底加入,氯化反应在925-1010温度下连续进行,TiO2及铁、硅、矾、钙、镁及其他金属的氧化物被转化成相应的氯
44、化物,随气体离开氯化炉。反应气体先经旋风分离器将没反应的固体粉尘和不挥发的氯化物从反应气体中分离出来,随后进行逐级冷却冷凝,先分离出亚铁的氯化物,再分离中沸点的氯化物三氯化铁,然后用冷四氯化钛喷淋等办法冷凝收集低沸点的氯化物四氯化钛(内含四氯化硅和三氯氧矾等),经过滤除泥浆,得到粗制四氯化钛。粗四氯化钛经除矾(一般用矿物油),再经蒸馏除去四氯化硅等低沸点杂质,得到相对高纯度的精制四氯化钛。高温下的氯气和四氯化钛极具腐蚀性,所以氯化炉即便是采用优质耐火材料,其使用寿命也是相对有限的。氯化最初反应的热量来自于电加热,采用碳电阻块,但一旦开始后,氯化反应将放出足够的热量,无需进一步外部加热。事实上,
45、为了控制氯化温度,加入氯化炉的石油焦和钛原料的量必须精确。如果氯化炉的温度太低,原料中的TiO2转化成TiCl4将不充分,而且未反应的氯气将通过氯化炉排出。如果温度太高,氯化炉的材料将融化,氯化炉将被“堵塞”。石油焦中碳的主要目的是将钛原料脱氧,使所含金属氯化。只有在存在还原剂的条件下,才能氯化TiO2。4.2.2氧化工段核心设备是氧化反应器。经蒸发预热的精制四氯化钛、经预热的氧气以及反应所必需的成核剂、晶型转化促进剂等反应物以各种方式加入氧化反应器。氧化反应引发温度在800以上,主反应一般在1300-1800进行。从反应器出来的气流(夹带着反应生成的二氧化钛颗粒)用低温的循环氯气骤冷到700
46、以下,再经沿程管路冷却到200,逐级用旋风分离器和布袋收集器将二氧化钛从氯气中分离出来,二氧化钛经脱氯处理后送后处理工序。在将TiCl4氧化成适于钛白应用的TiO2产品时,对其粒度控制非常严密,这是新建厂需解决技术诀窍。在反应温度下,氯气和四氯化钛都有极强的腐蚀性。所以氯化器常用不锈钢制成并衬有耐火材料。氧化反应必须在气相中进行,而且最好是温度刚刚超过600。因此,防止TiCl4冷凝到反应器壁上至关重要。通常用较大的反应空间并在TiCl4入口周围连续不断地导入惰性氮气流,可以达到此目的。为增加TiO2的收率,需在能形成TiO2粒子的地方周围加固体晶核。为此,有时将氯化铝(AlCl3)加到TiC
47、l4的进料装置中。氯化铝氧化成氧化铝(Al2O3),以细粒形式固化,提供了所需的晶核剂。输入的空气/氧气气流中所带的少量蒸汽在快速冷却阶段形成水滴,这也可起到晶核的作用促进TiO2粒子的形成。除尘器上捕集的TiO2含有大量的吸附氯,通过加热或更通常的蒸汽处理除去,洗掉的氯被转化成了盐酸。最后,用含硼酸0.1%的蒸汽进一步处理,消除微量的氯和吸附在TiO2粒子上的盐酸。4.2.3后处理工段后处理工段由打浆、研磨、化学品制备、表面处理、过滤洗涤、喷雾干燥、微粉碎及成品包装等主要工序组成:氧化工序来的TiO2粉料进入打浆槽,分散剂、脱盐水计量后分别加入打浆槽;打浆合格的浆液送研磨工序。打浆工序来的浆料进砂磨机进料槽再分散后,经砂磨机