Ethylene production economics

The light hydrocarbons produce only minor amounts of by-products, while naphtha and heavier feeds produce substantial quantities of propylene, butadiene, and aromatics. Thus, while in the United States these products are obtained generally from other routes at present, in Europe and Japan ethylene production serves as a major source of these chemicals. As discussed in greater detail later, by-product outlet considerations can play an important role in feedstock selection, and by-product realizations can have a major effect on the ethylene production economics. 

Plant size is important in ethylene production economics as in most manufacturing operations. The economy of scale for ethylene stems... 

The many factors involved in the ethylene production economics are interrelated in a complex manner. The more important variables relate to feedstock types and prices, by-product volumes and valuations, plant size, and severity of operation. 

Most by-product acetylene from ethylene production is hydrogenated to ethylene in the course of separation and purification of ethylene. In this process, however, acetylene can be recovered economically by solvent absorption instead of hydrogenation. Commercial recovery processes based on acetone, dimetbylform amide, or /V-metby1pyrro1idinone have a long history of successfiil operation. The difficulty in using this relatively low cost acetylene is that each 450, 000 t/yr world-scale ethylene plant only produces from 7000 9000 t/yr of acetylene. This is a small volume for an economically scaled derivatives unit. 

Ethanol to Ethylene. The economics of this process depend on the availabiUty and price of ethanol. High volume production of ethylene... 

Ethylene glycol industry, 24 270 Ethylene glycol monobutyl ether, acrylamide solubility in, l 290t Ethylene glycol production, economic aspects of, 12 652-653 Ethylene glycols (EGs), 10 664-665 12 113, 644-660. See also Glycols derivatives of, 12 656-660 diethers of, 12 658 from ethylene oxide, 10 596 health, safety, and environmental factors related to, 12 653-655 manufacture of, 12 648-652 monoethers of, 12 656-658 properties of, 12 645-648, 649t uses for, 12 645, 655-656... 

Perhaps the most important of these factors involves the raw material employed for this purpose and the by-product volumes and prices. In this connection we discuss the product distributions from potential various feedstocks and current trends in feedstock selection, illustrating the significant role feedstocks play in the ethylene commercial picture. In addition, the effects on production economics of the factors of plant size and severity of operation are investigated. 

Feed and By-Product Pricing Basis. Table V shows the feed and by-product price basis used in our economic calculations. Separate price structures are shown for the United States and Europe. For each case the by-product prices are assigned two values (a) fuel value and (b) premium or chemical value. Pricing the by-products on each basis yields two values of ethylene production costs for each case considered. These... 

Consumers can also negotiate with feedstock suppliers on upfront payments or payment terms under which they pay a higher price than the lowest market price at the trough, but pay lower prices when product prices spike. An interesting application of this is the potential for an ethane cracker operator to convert the economics of its cracker to those of a virtual naphtha cracker, by paying an integrated gas producer-processor a price for ethane indexed to naphtha-based ethylene production costs. 

Ethylene production has increased many fold in the last 40 to 50 years. In the United States, from 1960 to 2000, ethylene production increased from about 2.6 to 30 million metric tons/year while propylene production increased from 1.2 to 14 million tons/year. The growth rates on a yearly basis have, of course, depended in this time period on economic conditions in both the United States and worldwide. In 2000, worldwide production of ethylene was about 88 million tons/year the production capacity was 104 million tons/year. In 1960, about 70% of both the ethylene and the propylene produced was in the United States. Relative growth rates in the last few years of both ethylene and propylene production have... 

Economics For increase in naphtha-cracker ethylene production from 247,000 mtpy to 330,000 mtpy, based on U.S. Gulf Coast ... 

The key features of the thermodynamics of ethane pyrolysis are illustrated in Figure 2.1, which shows the free energy relationship of ethane to the product ethylene and other compounds of interest over a range of ten ratures. This graph illustrates several points which are central to the technology and production economics of ethylene production ... 

The sensitivity of the production economics for LSWR is illustrated in Figure 9.12 for the open system (all products sold at market price). This shows the production cost is very sensitive to the prevailing price of the feedstock. However, despite an increase in capital relative to the naphtha case, the production cost for ethylene is lower than the naphtha case due to the marked lower feedstock price by about 200/t for each of the scenarios. 

Ethylene glycol production by hydration of ethylene oxide. Economic data (France conditions, mkt-1986)... 

Table III shows the effect of shifting furnace operation from propane fresh feed to ethane. Data are from Schutt and Zdonik (54). The reduction of propylene yield from ethane to negligible levels in favor of increased ethylene production cannot be done if a plant has propylene commitments. Because propylene requirements cannot be satisfied with ethane feed, Ericsson (14) has concluded that propane will continue to be the preferred feedstock to make ethylene. Actually, 85% of the U.S. ethylene plants are located in the Gulf Coast area so that they can obtain and operate on economical ethane and propane feeds. The need for propane pyrolysis has resulted in a renewal of experimental interest in this area, and in-depth studies have been made by Crynes and Albright (17) and by Buekens and Froment (7).

The Energy Research Centre of The Netherlands (ECN) examined the feasibility of a number of routes to ethylene production, including the use of gas turbine reactors and heat exchanger reactors (Hugill et al., 2005). The aim of the study at ECN was to see if the economics of the production of ethylene from natural gas by the oxidative coupling of methane (OCM) could be improved, as at the time it was considered economically unfeasible. The study was based on the work of Swanenberg (1998),... 

The world s 140 million metric tons of annual ethylene capacity almost exclusively employs steam cracking of hydrocarbon feedstocks [5]. The majority of the feedstocks come from petroleum refining, such as by cracking of naphtha, but some producers use liquefied natural gas as a feedstock. In Brazil, where sugar cane is plentiful, Braskem has built a 200,000 metric ton per year ethylene plant based upon the dehydration of sugar-derived ethanol [6]. In the United States, natural gas liquids, a mixture of ethane, propane, butane, and other hydrocarbons, are available from shale deposits. The ethane is separated and cracked to make ethylene. Depending on the cost of oil and natural gas, this can be an economic advantage. In 2012, about 70% of United States ethylene production was from ethane [7]. 

PET production comprises two steps the esterification of TPA with EG and polycondensation, in which PET is formed via a trans-esterification reaction. For high-viscosity PET grades, the process includes a chain extension after an additional process step (Rieckmann and Volker, 2004). Accordingly, EG and TPA are derived from petroleum however, they can be alternatively produced via bio-based routes. Conventionally, EG is produced via the hydrolysis of ethylene oxide, a product of the oxidation of ethylene. The route for bio-based ethylene production has been exploited since 1989 with India Glycols. This route seemed to be technically and economically feasible however, the production of bio-based TPA is not as simple. 

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