pressure to find a solution as soon as possible so that production can restart, since ?down time‘ costs money.
（3）工艺改进。工艺改进与正在进行的工艺有关。它可能出现了某个问题使生产停止。在这种情形下，就面临着很大的压力要尽快地解决问题以便生产重新开始，因为故障期耗费资财。
down time: 故障期
More commonly, however, process improvement will be directed at improving the profitability of the process. This might be achieved in a number of ways. For example, improving the yield by optimizing the process, increasing the capacity by introducing a new catalyst, or lowering the energy requirements of the process. An example of the latter was the introduction of turbo compressors in the production of ammonia by the Haber process. This reduced utility costs (mainly electricity) from $6.66 to %0.56 per ton of ammonia produced. Improving the quality of the product, by process modification, may lead to new markets for the product.
然而，更为常见的，工艺改进是为了提高生产过程的利润。这可以通过很多途径实现。例如通过优化流程提高产量，引进新的催化剂提高效能，或降低生产过程所需要的能量。可说明后者的一个例子是在生产氨的过程中涡轮压缩机的引进。这使生产氨的成本（主要是电）从每吨6.66美元下降到0.56美元。通过工艺的改善提高产品质量也会为产品打开新的市场。
In recent years, however, the most important process improvement activity has been to reduce the environmental impact of the process, i.e., to prevent the process causing any pollution. Clearly there have been two interlinked driving forces for this. Firstly, the public‘s concern about the safety of chemicals and their effect on the environment, and the legislation which has followed as a result of this. Secondly the cost to the manufacturer of having to treat waste (i.e., material which cannot be recovered and used r sold) so that it can be safely disposed of, say by pumping into a river. This obviously represents a charge on the process which will increase the cost of the chemical being made. The potential for improvement by reducing the amount of waste is self-evident.
然而，近年来，最重要的工艺改进行为主要是减少生产过程对环境的影响，亦即防止生产过程所引起的污染。很明显，有两个相关连的因素推动这样做。第一，公众对化学产品的安全性及其对环境所产生影响的关注以及由此而制订出来的法律；第二，生产者必须花钱对废物进行处理以便它能安全地清除，比如说，排放到河水中。显然这是生产过程的又一笔费用，它将增加所生产化学产品的成本。通过减少废物数量提高效益其潜能是不言而喻的。
Note, however, with a plant which has already been built and is operating there are usually only very limited physical changes which can be made to the plant to achieve the above aims. Hence the importance, already mentioned, of eliminating waste production at the design stage of a new plant. Conserving energy and thus reducing energy cost has been another major preoccupation in recent years.
然而，请注意，对于一个已经建好并正在运行的工厂来说，只能做一些有限的改变来达到上述目的。因此，上面所提到的减少废品的重要性应在新公厂的设计阶段加以考虑。近年来另一个当务之急是保护能源及降低能源消耗。
(4) Applications development. Clearly the discovery of new applications or uses for a product can
increase or prolong its profitability. Not only does this generate more income but the resulting increased scale of production can lead to lower unit costs and increased profit. An example is PVC whose early uses included records and plastic raincoats. Applications which came later included plastic bags and particularly engineering uses in pipes and guttering.
（4）应用开发。显然发掘一个产品新的用处或新的用途能拓宽它的获利渠道。这不仅能创造更多的收入，而且由于产量的增加使单元生产成本降低，从而使利润提高。举例来说，PVC早期是用来制造唱片和塑料雨衣的，后来的用途扩展到塑料薄膜，特别是工程上所使用的管子和排水槽。
Emphasis has already been placed on the fact that chemicals are usually purchased for the effect, or particular use, or application which they have. This often means that there will be close liaison between the chemical companies‘ technical sales representatives and the customer, and the level of technical support for the customer can be a major factor in winning sales. Research and development chemists provide the support for these applications developments. An example is CF3CH3F. This is the first of the CFC replacements and has been developed as a extracting natural products from plant materials. In no way was this envisaged when the compound was first being made for use as a refrigerant gas, but it clearly is an example of applications development. 我们已经强调了化学产品是由于它们的效果，或特殊的用途、用处而得以售出这个事实。这就意味着化工产品公司的技术销售代表与顾客之间应有密切的联系。对顾客的技术支持水平往往是赢得销售的一个重要的因素。进行研究和开发的化学家们为这些应用开发提供了帮助。CH3CH3F的制造就是一个例子。它最开始是用来做含氟氯烃的替代物作冷冻剂的。然而近来发现它还可以用作从植物中萃取出来的天然物质的溶解剂。当它作为制冷剂被制造时，固然没有预计到这一点，但它显然也是应用开发的一个例子。
3.Variations in R&D Activities across the Chemical Industry
Both the nature and amount of R&D carried out varies significantly across the various sectors of the chemical industry. In sectors which involve largescale production of basic chemicals and where the chemistry, products and technology change only slowly because the process are mature, R&D expenditure is at the lower end of the range for the chemical industry. Most of this will be devoted to process improvement and effluent treatment. Examples include ammonia, fertilizers and chloralkali production from the inorganic side, and basic petrochemical intermediates such a ethylene from the organic side.
3．化工行业中研究与开发活动的变化
化学工业的不同部门所进行的R&D的性质与数量都有很大的变化。与大规模生产的基础化工产品有关的部门中，化学产品和技术变化都很慢，因为流程已很成熟。R&D经费支出属于化工行业中低的一端，而且大部分的费用是用于过程改进和废水处理。无机方面的例子有氨、肥料和氯碱的生产，有机方面的如乙烯等一些基础石油化学的中间产物。
At the other end of the scale lie pharmaceuticals and pesticides (or plant protection products). Here there are immense and continuous efforts to synthesize new molecules which exert the desired, specific biological effect. A single company may generate 10,000 new compounds for screening each year. Little wonder that some individual pharmaceutical company‘s annual R&D expenditure is now approaching $1000 million! Expressing this in a different way they spend in excess of 14% of sales income (note not profits) on R&D.
不一样规模生产的是药品和除草剂。人们付出了巨大而持续的努力以合成能产生所希望的、特殊的生物作用的新分子。一家公司每年可能要合成10,000新化合物以供筛选。可以想象一些医药公司其每年的R&D经费支出高达100亿美元。换句话说，他们把超过14%的销售收入投入在R&D上。
Unit 3 Typical Activities of Chemical Engineers
化学工程师的例行工作
The classical role of the chemical engineer is to take the discoveries made by the chemist in the laboratory and develop them into money--making, commercial-scale chemical processes. The chemist works in test tubes and Parr bombs with very small quantities of reactants and products (e.g., 100 ml), usually running ―batch‖, constant-temperature experiments. Reactants are placed in a small container in a constant temperature bath. A catalyst is added and the reactions proceed with time. Samples are taken at appropriate intervals to follow the consumption of the reactants and the production of products as time progresses.
化学工程师经典的角色是把化学家在实验室里的发现拿来并发展成为能赚钱的、商业规模的化学过程。化学家用少量的反应物在试管和派式氧弹中反应相应得到少量的生成物，所进行的通常是间歇性的恒温下的实验，反应物放在很小的置于恒温水槽的容器中，加点催化剂，反应继续进行，随时间推移，反应物被消耗，并有生成物产生，产物在合适的间歇时间获得。
By contrast, the chemical engineer typically works with much larger quantities of material and with very large (and expensive) equipment. Reactors can hold 1,000 gallons to 10,000 gallons or more. Distillation columns can be over 100 feet high and 10 to 30 feet in diameter. The capital investment for one process unit in a chemical plant may exceed $100 million!
与之相比，化学工程师通常面对的是数量多得多的物质和庞大的（昂贵的）设备。反应器可以容纳1000 到10,000加仑甚至更多。蒸馏塔有100英尺多高，直径10到30英尺。化工厂一个单元流程的投资可能超过1亿美元。
The chemical engineer is often involved in ―scaling up‖ a chemist-developed small-scale reactor and separation system to a very large commercial plant. The chemical engineer must work closely with the chemist in order to understand thoroughly the chemistry involved in the process and to make sure that the chemist gets the reaction kinetic data and the physical property data needed to design, operate, and optimize the process. This is why the chemical engineering curriculum contains so many chemistry courses.
在把化学家研制的小型反应器及分离系统“放大”到很大的商业化车间时，通常需要化学工程师的参与。为了彻底了解过程中的化学反应，化学工程师必须与化学家密切合作以确保能得到所需要的反应的动力学性质和物理性质参数以进行设计、运转和优选流程。这就是为什么化工课程要包括那么多的化学类课程的原因。
The chemical engineer must also work closely with mechanical, electrical, civil, and metallurgical engineers in order to design and operate the physical equipment in a plant--the reactors, tanks, distillation columns, heat exchangers, pumps, compressors, Control and instrumentation devices, and so on. One big item that is always on such an equipment list is piping. One of the most impressive features f a typical chemical plant is the tremendous number of pipes running all over the site, literally hundreds of miles in many plants. These pipes transfer process materials (gases
and liquids) into and out of the plant. They also carry utilities (steam, cooling water, air, nitrogen, and refrigerant) to the process units. 化学工程师还必须与机械、电子、土木建筑和冶金工程师密切协作以设计和操作工厂的机械设备—反应器、槽、蒸馏塔、热交换器、泵、压缩机、控制器和仪器设备等等。在这张设备单上还有一大类是管子。化工厂最典型的特征之一就是数目庞大的管道贯穿所有生产间。可以毫不夸张地说，在许多车间都有几百英里长的管道。这些管道输入和输出车间的反应物质进行传递，同时还可携带有用的东西（水蒸气、冷却水、空气、氧、冷却剂）进入操作单元。
To commercialize the laboratory chemistry, the chemical engineer is involved in development, design, construction, operation, sales, and research. The terminology used to label these functions is by no means uniform from company to company, but a rose by any other name is still a rose. Let us describe each of these functions briefly. It should be emphasized that the jobs we shall discuss are ―typical‖ and ―classical‖, but are by no means the only things that chemical engineers do. The chemical engineer has a broad background in mathematics, chemistry, and physics. Therefore, he or she can, and does, fill a rich variety of jobs in industry, government, and academia.
要把实验室研究商业化，化学工程师要参与进行开发、设计、建筑、操作、销售和研究工作。各个公司用来表示这些工作的名词不完全一样，但万变不离其宗。让我们简单地把每个工作描述一下。应该强调的是，我们所讨论的工作是“典型的”和“经典的”，但并不意味着化学工程师只能做这些事。化学工程师在数学、化学和物理学方面都有很好的知识基础，因此，他或她能够而且确实适应工业、政府部门、大专院校等非常广泛的职业要求。
1. Development
Development is the intermediate step required in passing from a laboratory-size process to a commercial-size process. The ―pilot-plant‖ process involved in development might involve reactors that are five gallons in capacity and distillation columns that are three inches in diameter. Development is usually part of the commercialization of a chemical process because the scale-up problem is a very difficult one. Jumping directly from test tubes to 10,000-gallon reactors can be a tricky and sometimes dangerous endeavor. Some of the subtle problems involved which are not at all obvious to the uninitiated include mixing imperfections, increasing radial temperature gradients, and decreasing ratios of heat transfer areas to heat generation rates. 1. 开发
开发工作是从实验室规模向商业化规模转化所必需的中间阶段。开发阶段所涉及的“中试”流程所使用的反应器容量为5加仑，蒸馏塔直径为3英寸。开发通常是化学流程商业化的一部分。因为“放大”规模是一个非常困难的问题。直接从试管研制跳到在10.000加仑反应器里生产是非常棘手的有时甚至是危险的工作。一些（在实验室研究阶段）根本不明显的未加以考虑的细微问题，如混合不均匀，温度梯度辐射状升高，热交换面积逐渐降低以及热交换速度下降等（在后一阶段变得影响很大）。
The chemical engineer works with the chemist and a team of other engineers to design, construct, and operate the pilot plant. The design aspect involves specifying equipment sizes, configuration, and materials of construction. Usually pilot plants are designed to be quite flexible, so that a wide variety of conditions and configurations can be evaluated.
化学工程师与化学家和其他一些工程师协作对中师车间进行设计、安装和运行，设计方面包