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部分化學(xué)工程與工藝專業(yè)英語(yǔ)課文翻譯胡鳴劉霞編-資料下載頁(yè)

2024-10-24 23:25本頁(yè)面

【導(dǎo)讀】可以認(rèn)為它起源于工業(yè)革命其間,大約在1800年,并發(fā)展成為為其它工。業(yè)部門(mén)提供化學(xué)原料的產(chǎn)業(yè)。比如制肥皂所用的堿,棉布生產(chǎn)所用的漂白粉,玻璃制造業(yè)所。用的硅及Na2CO3.我們會(huì)注意到所有這些都是無(wú)機(jī)物。有機(jī)化學(xué)工業(yè)的開(kāi)始是在十九世紀(jì)。六十年代以WilliamHenryPerkin發(fā)現(xiàn)第一種合成染料—苯胺紫并加以開(kāi)發(fā)利用為標(biāo)志的。在世界化學(xué)產(chǎn)品市場(chǎng)上占有75%的份額。這要?dú)w因于新染料的發(fā)現(xiàn)以及硫酸的接觸法生產(chǎn)。和氨的哈伯生產(chǎn)工藝的發(fā)展。而后者需要較大的技術(shù)突破使得化學(xué)反應(yīng)第一次可以在非常高。的壓力條件下進(jìn)行。這方面所取得的成績(jī)對(duì)德國(guó)很有幫助。大仗的爆發(fā),對(duì)以氮為基礎(chǔ)的化合物的需求飛速增長(zhǎng)。這種深刻的改變一直持續(xù)到戰(zhàn)后。盡管這種發(fā)展的速度近年來(lái)?;瘜W(xué)工業(yè)的發(fā)展由于1950年以來(lái)石油化學(xué)領(lǐng)域的研究和開(kāi)發(fā)大部分在有機(jī)化。石油化工在60年代和70年代的迅猛發(fā)展主要是由于人們對(duì)于合成高聚物如聚。乙烯、聚丙烯、尼龍、聚脂和環(huán)氧樹(shù)脂的需求巨大增加。

  

【正文】 鋼發(fā)酵器。而在 第一次世界大戰(zhàn)中,死于傷口感染的士兵比直接死于戰(zhàn)場(chǎng)上的人還要多。注意到這一點(diǎn)不能不讓我們心存感激。 Process development for a new product depends on things such as the scale on which it is to be manufactured, the byproducts formed and their removal/recovery, and required purity. Data will be acquired during this development stage using semitechnical plant (up to 100 liters capacity) which will be invaluable in the design of the actual manufacturing plant. If the plant is to 10 be a very large capacity, continuously operating one, . petrochemical or ammonia, then a pilot plant will first be built and operated to test out the process and acquire more data, these semitechnical or pilot plants will be required for testing, ., a pesticide, or customer evaluation, ., a new polymer. 對(duì)一個(gè)新產(chǎn)品進(jìn)行開(kāi)發(fā)要考慮產(chǎn)品生產(chǎn)的規(guī)模、產(chǎn)生的副產(chǎn)品以及分離 /回收,產(chǎn)品所要求的純度。在開(kāi)發(fā)階段利用中試車(chē)間(最大容量可達(dá) 100 升)獲得的數(shù)據(jù)設(shè)計(jì)實(shí)際的制造廠是非常寶貴的,例如石油化工或氨的生產(chǎn)。要先建立一個(gè)中試車(chē)間,運(yùn)轉(zhuǎn)并測(cè)試流程以獲得更多的數(shù)據(jù)。他們需要測(cè)試產(chǎn)品的性質(zhì),如殺蟲(chóng)劑,或進(jìn)行消費(fèi)評(píng)估,如一種新的聚合物。 Note that byproducts can has a major influence on the economics of a chemical process. Phenol manufacture provides a striking example of this. The original route, the benzenesulphonic acid route, has bee obsolete because demand for its byproduce sodium sulfite ( tons/l ton phenol) has dried up. Its recovery and disposal will therefore be an additional charge on the process, thus increasing the cost of the phenol. In contrast the cumene route owes its economic advantage over all the other routes to the strong demand for the byproduct acetone ( tons/l ton phenol).The sale of this therefore reduces the cost of the phenol. 注意,副產(chǎn)品對(duì)于化學(xué)過(guò)程的經(jīng)濟(jì)效益也有很大的影響。酚的生產(chǎn)就是一個(gè)有代表性的例子。早期的方法,苯磺酸方法,由于它的副產(chǎn)品亞硫酸鈉需求枯竭而變的過(guò)時(shí)。亞硫酸鈉需回收和廢置成為生產(chǎn)過(guò)程附加的費(fèi)用,增加了生產(chǎn)酚的成本。相反,異丙基苯方法,在經(jīng)濟(jì)效益方面優(yōu)于所有其他方法就在于市場(chǎng)對(duì)于它的副產(chǎn)品丙酮的迫切需求。丙酮的銷(xiāo)售所得降低了酚的生產(chǎn)成本。 A major part of the process development activity for a mew plant is to minimize, or ideally prevent by designing out, waste production and hence possible pollution. The economic and environmental advantages of this are obvious. 對(duì)一個(gè)新產(chǎn)品進(jìn)行工藝開(kāi)發(fā)的一個(gè)重要部分是通過(guò)設(shè)計(jì)把廢品減到最低,或盡可能地防止可能的污染,這樣做帶來(lái)的經(jīng)濟(jì)利益和對(duì)環(huán)境的益處是顯而易見(jiàn)的。 Finally it should be noted that process development requires a big team effort between chemists, chemical engineers, and electrical and mechanical engineers to be successful. 最后要注意,工業(yè)開(kāi)發(fā)需要包括化學(xué)家、化學(xué)工程師、電子和機(jī)械工程師這樣一支龐大隊(duì)伍的協(xié)同合作才能取得成功。 ( 3) Process improvement. Process improvement relates to processes which are already operating. It may be a problem that has arisen and stopped production. In this situation there is a lot of pressure to find a solution as soon as possible so that production can restart, since ?down time‘ costs money. ( 3)工藝改進(jìn)。工藝改進(jìn)與正在進(jìn)行的工藝有關(guān)。它可能出現(xiàn)了某個(gè)問(wèn)題使生產(chǎn)停止。在這種情形下,就面臨著很大的壓力要盡快地解決問(wèn)題以便生產(chǎn)重新開(kāi)始,因?yàn)楣收掀诤馁M(fèi)資財(cái)。 down time: 故障期 More monly, 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 11 lowering the energy requirements of the process. An example of the latter was the introduction of turbo pressors in the production of ammonia by the Haber process. This reduced utility costs (mainly electricity) from $ to % per ton of ammonia produced. Improving the quality of the product, by process modification, may lead to new markets for the product. 然而,更為常見(jiàn)的,工藝改進(jìn)是為了提高生產(chǎn)過(guò)程的利潤(rùn)。這可以通過(guò)很多途徑實(shí)現(xiàn)。例如通過(guò)優(yōu)化流程提高產(chǎn)量,引進(jìn)新的催化劑提高效能,或降低生產(chǎn)過(guò)程所需要的能量??烧f(shuō)明后者的一個(gè)例子是在生產(chǎn)氨的過(guò)程中渦輪壓縮機(jī)的引進(jìn)。這使生產(chǎn)氨的成本(主要是電)從每噸 美元下降到 美元。通過(guò)工藝的改善提高產(chǎn)品質(zhì)量也會(huì)為產(chǎn)品打開(kāi)新的市場(chǎng)。 In recent years, however, the most important process improvement activity has been to reduce the environmental impact of the process, ., 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 (., 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 selfevident. 然而,近年來(lái),最重要的工藝改進(jìn)行為主要是減少生產(chǎn)過(guò)程對(duì)環(huán)境的影響,亦即防止生產(chǎn)過(guò)程所引起的污染。很明顯,有兩個(gè)相關(guān)連的因素推動(dòng)這樣做。第一,公眾對(duì)化學(xué)產(chǎn) 品的安全性及其對(duì)環(huán)境所產(chǎn)生影響的關(guān)注以及由此而制訂出來(lái)的法律;第二,生產(chǎn)者必須花錢(qián)對(duì)廢物進(jìn)行處理以便它能安全地清除,比如說(shuō),排放到河水中。顯然這是生產(chǎn)過(guò)程的又一筆費(fèi)用,它將增加所生產(chǎn)化學(xué)產(chǎn)品的成本。通過(guò)減少?gòu)U物數(shù)量提高效益其潛能是不言而喻的。 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,請(qǐng)注意,對(duì)于一個(gè)已經(jīng)建好并正在運(yùn)行的工廠來(lái)說(shuō),只能做一些有限的改變來(lái)達(dá)到上述目的。因此,上面所提到的減少?gòu)U品的重要性應(yīng)在新公廠的設(shè)計(jì)階段加以考慮。近年來(lái)另一個(gè)當(dāng)務(wù)之急是保護(hù)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 ine 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)應(yīng)用開(kāi)發(fā)。顯然發(fā)掘一個(gè)產(chǎn)品新的用處或新的用途能拓寬它的獲利渠道。這不僅能創(chuàng)造更多的收入,而且由于產(chǎn)量的增加使單元生產(chǎn)成本降低,從而使利潤(rùn)提高。舉例來(lái)說(shuō),PVC 早期是用來(lái)制造唱片和塑料雨衣的,后來(lái)的用途擴(kuò)展到塑料薄膜,特別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 12 effect, or particular use, or application which they have. This often means that there will be close liaison between the chemical panies‘ technical sales representatives and the customer, and the level
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