大学化工专业英语Lesson.doc

WORD格式可编辑 技术资料 专业整理 Chlor-Alkali and Related Processes 氯碱工业与相关过程 Historically the bulk chemical industry was built on chlor-alkali and related processes. 纵观历史，大部分化学工业是建立在氯碱工业及其相关过程之上。 The segment is normally taken to include the production of chlorine gas, caustic soda（sodium hydroxide）, soda-ash（derivatives of sodium carbonate in various forms） and, for convenience, lime-based products. 该部分通常包括氯气、苛性钠（氢氧化钠）、无水碳酸钠（以各种形式存在的碳酸钠的衍生物），以及以石灰为基础的产品。 Soda-ash and sodium hydroxide have competed with each other as the major source of alkali ever since viable processes were discovered for both. 作为碱的主要来源，自从发现很多过程对于纯碱和火碱都是可行的，它们就相互竞争。 The peculiar economics of electrolytic processes mean that you have to make chlorine and caustic soda together in a fixed ratio whatever the relative demand for the two totally different types of product, and this causes swings in the price of caustic soda which can render soda-ash more or less favorable as an alkali. 电解过程的特殊经济性意味着，不管对氯气和氢氧化钠这两种不同类型的产品的相对需求量如何，你只有以固定的比例同时制备氯气和氢氧化钠。这引起了氢氧化钠的价格的摇摆不定，从而使得纯碱作为一种碱或多或少有利。 Both chlorine/caustic soda and soda-ash production are dependent on cheap readily available supplies of raw materials. 氯气/氢氧化钠和纯碱的生产都依赖于廉价的现成的原材料供应。 Chlorine/caustic soda requires a ready supply of cheap brine and electricity, soda-ash requires brine, limestone and lots of energy. 氯气/氢氧化钠需要廉价的现成的卤水和电力的供应，纯碱需要卤水、石灰石和大量的能量。 Soda-ash plants are only profitable if their raw materials do not have to be transported far. 如果纯碱厂的原材料不需要运输的话，它们是盈利的。 The availability of such supplies is a major factor in the location of many of the chemical industry’s great complexes. 在许多化学工业的重大复合物的位置中，这种供货的可行性是一个主要因素。 1. Lime-Based Products 1. 基于石灰的产品 One of the key raw materials is lime. 一种重要的原料是石灰。 Limestone consists mostly of calcium carbonate（CaCO3） laid down over geological time by various marine organisms. 石灰石主要由CaCO3组成，CaCO3是多种多样的海洋生物经过整个地质年代留下来的。 High quality limestones are often good enough to be used directly a