Ethylene crackers

Pyrolysis gasoline is a by-product of the steam cracking of hydrocarbon feeds in ethylene crackers (see Ethylene). Pyrolysis gasoline typically contains about 50—70 wt % aromatics, of which roughly 50% is benzene, 30% is toluene, and 20% is mixed xylenes (which includes EB). 

M. Dente and co-workers, "Ethylene Cracker Transferline Exchanger Fouling," paper presented atMJOE Meetings Houston, March 1983. 

The success of Linde s process and engineering contracting business is discussed. Its proprietary technology includes petrochemical projects, largely ethylene crackers, which account for roughly half of its sales, and over 300 processes protected by 1500 patents. 

Traditional olefin plants have more than one alias. One is even fraudulent. They are variously called ethylene plants after their primary product steam crackers because the feed is usiuilly mixed with steam before it is cracked or whatever aacker, where whatever is the name of the feed (ethane cracker, gas oil cracker, etc.). Olefin plants are sometimes referred to as ethylene crackers, biit only those who don t know any better, use that misnomer. Ethylene is not cracked but rather is the product of cracking. 

Together with China Petroleum Chemical Corp. (Sinopec) in a 50-50 partnership, BASF planned to build its first Verbund project in East Asia - an integrated petrochemical site (IPS) on 220 hectares of land. The core of the project was an ethylene cracker with a capacity of 600,000 tons per year. Nine new plants downstream would be supplied by the cracker, producing 1.7 million metric tons of chemical products for local consumption, including ethylene, aromatics, poly-ethylenes, ethylene oxide and ethylene glycols, acrylic acid, acrylates, oxo alcohols, formic acid, propionic acid, methylamine, and dimethylformamide. 

Acetylene hydrogenation. Selective hydrogenation of acetylene to ethylene is performed at 200°C over sulfided nickel catalysts or carbon-monoxide-poisoned palladium on alumina catalyst. Without the correct amount of poisoning, ethane would be the product. Continuous feed of sulfur or carbon monoxide must occur or too much hydrogen is chemisorbed on the catalyst surface. Complex control systems analyze the amount of acetylene in an ethylene cracker effluent and automatically adjust the poisoning level to prepare the catalyst surface for removing various quantities of acetylene with maximum selectivity. 

Total domestic capcity of MTBE in the US is, however, limited by the availability of isobutylene. The most available source of isobutylene is from ethylene crackers and if all from that source were utilized to produce MTBE this would yield only 50,000 bbl/day of MTBE. All available isobutylene would produce 200,000 bbl/day of MTBE. At blends of 7%, this would only satisfy the existing unleaded gasoline market, but not that being opened up by the phasing down of lead in gasoline scheduled for October of this year. 

Likewise, Dow Chemical Company, instituted a major corporate restructuring in 2009 which included the shutdown of as many as 20 manufacturing plants, including an ethylene cracker in Louisiana, and ethylene derivative facilities in Louisiana and Texas. The closings reduced Dow s ethylene demand by... 

Another opportunity for advancement in ethylbenzene synthesis is in the development of liquid phase processes that can handle low cost feedstocks, including dilute ethylene such as ethane/ethylene mixtures. The use of dilute ethylene has become increasingly attractive since it has the potential to debottleneck ethylene crackers. Currently higher temperature, vapor phase technologies can tolerate contaminants that enter with the dilute ethylene feed from FCC units. However, these same contaminants can accelerate catalyst aging in lower temperature, liquid phase operations because they are more strongly adsorbed at the lower temperatures. Acid catalysts that tolerate elevated levels of contaminants would facilitate the development of dilute ethylene-based processes. These same catalysts could be useful in applications where lower cost or lower quality benzene feeds are all that are available. 

Application Separation of pure C4 olefins from olefinic/paraffinic C4 mixtures via extractive distillation using a selective solvent. BUTENEX is the Uhde technology to separate light olefins from various C4 feedstocks, which include ethylene cracker and FCC sources. 

Indian Petrochemical Corporation Ltd. (IPCL) is a government owned corporation with the remit to expand the petrochemical and plastics production of India. It has a naphtha based ethylene cracker at Vadodara (132,000 t/y), and large gas based complexes at Nagothane near Mumbai (Bombay 400,000 t/y) and Dahej near Bharuch in Gujarat (300,000 t/y). The company produces polymers, fibre intermediates, catalysts and absorbents. 

Gas Authority of India (GAIL) is a government authority that markets gas produced by various upstream producing consortia. GAIL operates a 300,000 t/y ethylene cracker at Pata in Uttar Pradesh. The ethylene is processed downstream to HDPE and LLDPE. 

The performance of the PPR for NOx removal by the Shell low-temperature NOx reduction has been investigated extensively [20]. In the first commercial application of the Shell process with parallel-passage reactors, flue gases of six ethylene cracker furnaces at Rheinische Olefin Werke at Wesseling, Germany, are treated in a PPR system with 120-m catalyst in total to reduce the nitrogen oxide emissions to about 40 ppm v. Since its successful start-up in April 1990, the unit has performed according to expectations... 

Note S-995,3-mm spheres, in a semi industrial fixed-bed reactor treating a slip stream of flue gas from a commercial ethylene cracker furnace. (From Ref. 19.)... 

Thermal conductivity, H/C ratio, specific volume and specific heat vary during the chemical evolution of the deposit. Unfortunately, there is very small quantity of data in the literature on thermal conductivity. In fact, what little there is refers to coke or bitumen and provides limited or sometimes contradictory information because of the high dependency on the structure and composition of the solid. More reliable data refer to disordered graphite, similar to an aged deposit, without hydrogen and with a low porosity. The available experimental data on the time evolution of pressure drop and tube metal temperature in pyrolysis coils of ethylene crackers only permit rough estimates of the overall and average thickness and thermal conductivity of the deposit. 

Hj/Ught hydrocarbons Ethylene cracker old trains Cryogenic distillation PmSP PMP Pd-based Pilot plant Lab scale... 

BASF also found that while this reaction works well with pure butadiene, it will also work with "crude" butadiene, the C4 olefin cut from an ethylene cracker. The butenes in the C4 cut are inert under the reaction conditions. 

It is important to visualize a typically high-technology, very capital-intensive industry, where an individual plant and its control equipment can cost hundreds of millions of dollars. All large plants run on a continuous basis, and complete automatic control by computer or microprocessor is quite common. Some of these giants (mainly ethylene crackers) have capacities in excess of 500000 tonnes per annum. Development of more cost-effective routes and advances in technology have quite often meant that existing plant and processes have rapidly become redundant. For example, development of the cumene route to phenol meant that the benzenesulphonic acid route became obsolete some years ago. 

Somewhat similar net figures are obtained for the autot hermal cracking of crude oil if the ethylene coproduct is credited at 2 MJ/mol. Even with chemical values attached to co-products, the petrochemical processes consume over 3 MJ/mol for the production of acetylene. Furthermore, the capital costs for these processes are appreciably higher than for ethylene crackers. Thus, while the production costs of acetylene show considerable variations from one location to another, it is invariably dearer, by 30% to over 100%, than ethylene. 

Although it may be unhelpful to push the distinction too far, there are noticeable differences in terms of process wastes between the commodity/ bulk/heavy chemical sector and fine chemicals. The former are generally much more efficient at putting atoms of reagent into product [21] which is just as well bearing in mind the scale on which they operate In most cases the product is the desired one although in some, for example cracking of hydrocarbons such as naphtha to produce ethylene, the yield of ethylene leaves room for improvement, and it has been said by some in the industry that operation of ethylene crackers takes one into businesses, due to the coproducts, which one has no wish to be in. 

Against this background of global warming and CQ2 emissions reduction initiatives, this paper presents a flare reduction option for an existing ethylene plant during plant start up and shutdown. This study is conducted at Qatar Chemical Company in the Ras Laffan Olefins Company, ethylene cracker with a capacity of 1.3 MTPA production which was started up in April 2010. 

Treated gas H2S content specification of 4 ppm vol. can never be violated whereas the CO2 content limit of 1% vol. can be marginally deviated without violating the specification limit of Ethane rich gas supplied to Ethylene crackers and Lean gas supplied to the Industrial consumers. 

Flaring and venting are two activities associated with oil and gas production. It is a combustion process used to dispose gases through vertical stacks or ground flares. Qatar is a world leader in gas and hydrocarbon processing. It has a world class Ethylene Cracker, Ras Laffan Olefins Company Limited (RLOC), of 1.3 million mtpa capacity. RLOC started up in April 15, 2010 and is operated by Qatar Chemical Company (QChem). 

Mol, A., How Various Parameters Affect Ethylene Cracker Run Lengths, Hydrocarbon Processing, July, 1974. 

Feedstocks. Feedstocks for the oil-fumace process are heavy fuel oils. Preferred oils have high aromaticity, are free of suspended solids, and have a minimum of asphaltenes. Suitable oils are catalytic cracker residue (once residual catalyst has been removed), ethylene cracker residues, and distilled heavy coal tar fractions. Other specifications of importance are freedom from solid materials, moderate to low sulfur, and low alkali metals. The ability to handle such oils in tanks, pumps, transfer lines, and spray nozzles is also a primary requirement. 

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