Feedstock production, economics

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. 

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. 

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. 

Companies seek to make their plants more efficient and cost competitive. New catalysts are screened, alternative feedstocks tested, and changes in process equipment evaluated to improve product quality and production economics. The risk of making changes in a plant without laboratory or pilot plant work is usually too great, although here are exceptions. 

Indeed, an apparent disadvantaged technique could benefit from specific cooside-radons (adaptation to available feedstock, product quality, financial conditions of a preject) to offset an economic inferiority in relation to the competitioa... 

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. 

The book is based on a series of workshops and specialist seminars given by the author dating Ifom 1996 in Singapore and Kuala Lumpur. The workshops focussed on production economics, improving plant profitability, feedstock supply and cost. The book is an updated and expanded version of the author s workshop notes. 

Note that these economic results are not readily transferable to other regions of the country most data of this type are site-specific. Biomass feedstock production costs are highly variable in different regions and depend on the climate, production technology, on-farm costs, and capital costs (cf. Table 4.15). Electricity costs are also highly variable in different regions of the... 

Figure 1.6 indicates where a lubricant base oil plant fits into the process flow scheme of a typical refinery - if ever there is such a thing. Although the scheme is simplified, the inter-relationship between the base oil plant and other process units and product streams is evident. In a sense, the base oil plant and the fuel-upgrading plant, such as the catalytic cracker, compete for feedstock from vacuum distillation. These interactions are very important to the logistics and production economics of producing base oils. 

This variety allows biorefineries to be spread into different geographical regions, but it also requires different technological approaches. Chapter 6 elucidates different biorefinery concepts and shows different possible products. Economic and production advantages increase with the level of integration in the biorefinery-it is one of the conclusions drawn in this chapter. This means that the more competitive a biorefinery is the more products it is able to produce from its feedstock... 

Attached are relevant data on feedstocks, product specifications, utilities and economic data that should be useful for this design project. Additional data are also available in several articles in the library. For this production rate there are several competing technologies. To produce a competitive design, we would like to consider all of these technologies. These articles form only the start of your literature search. You will need to investigate potential ideas for this project thoroughly. 

Because of the concerns about an adequate and reliable supply of petroleum due to the pricing actions of the Organization of Petroleum Exporting Countries (OPEC), the 1970s also saw an interest in the development of bio-based feedstocks for the production of plastics and elastomers. In recent years this area has seen renewed attention as companies pursue their sustainability objectives and look to replace nonrenewable feedstocks with renewable feedstocks where economically and environmentally sustainable. 

A basic plant flowsheet-linked economic model, which simulates the process and calculates both capital and operating cost/revenue impUcations of different process configurations, capacities, feedstock, product slate, etc. as may be required. Such models are commercially available for plants emplo5ung more standardized unit-processes built in high numbers, such as oil refineries, but can of course be built up for any plant. 

The benchmark feeds indicated in Table 11.2 have been extensively tested in both laboratory and commercial settings and are known to produce MES products of low color and disalt content suitable for use in liquid and powder products. The C16 is preferred over C16-C18 for a sulfonation feedstock because it makes a better color MES and has proven product quality and excellent detergency characteristics it will become more widely available as a feedstock, the economics of producing detergent-grade ME favors C16 (requires less hydrogenation). 

Methanol production economics highly depend on the feedstock selection and feedstock prices. Methanol can be manufactured from any hydrocarbon source naphtha, oil, coal, wood, biomass, LPG, etc. The naphtha, fraction of crude oil... 

Table 14.4 shows a list of CALB lipase-catalyzed transesteiilicalion reactions using methanol as the acyl acceptor. Althongh methanol is the cheapest sonrce of acyl acceptor, it has a harmful effect on biocatalysts, hi countries whoe ethanol production firam renewable feedstocks is economically feasible, ethanol is the more preferable acyl acceptor (IQijima et al 2004). 

In many cases it is of interest to an ammonia producer to improve the production economics of an existing plant by the addition of new equipment or modification of existing equipment, by optimization of the operation, for example by installation of new and more efficient catalysts, or in some cases by a change of feedstock, etc. An important element in such a modernization of an ammonia plant, which is most often referred to as a revamp of the plant, is in many cases a modernization of the converter system. 

A detailed study of the properties of the potential products is of prime technical and economic importance, because it allows the refiner to have a choice in selecting feedstocks for his different units for separation, transformation and conversion, to set their operating conditions, in order to satisfy the needs of the marketplace in the best ways possible. 

Since 1960, the Hquid-phase oxidation of ethylene has been the process of choice for the manufacture of acetaldehyde. There is, however, stiU some commercial production by the partial oxidation of ethyl alcohol and hydration of acetylene. The economics of the various processes are strongly dependent on the prices of the feedstocks. Acetaldehyde is also formed as a coproduct in the high temperature oxidation of butane. A more recently developed rhodium catalyzed process produces acetaldehyde from synthesis gas as a coproduct with ethyl alcohol and acetic acid (83—94). 

Olefin Sources. The choice of feedstock depends on the alcohol product properties desired, availabiUty of the olefin, and economics. A given producer may either process different olefins for different products or change feedstock for the same appHcation. Feedstocks beheved to be currentiy available are as follows. 

Coal is used ia industry both as a fuel and ia much lower volume as a source of chemicals. In this respect it is like petroleum and natural gas whose consumption also is heavily dominated by fuel use. Coal was once the principal feedstock for chemical production, but ia the 1950s it became more economical to obtain most industrial chemicals from petroleum and gas. Nevertheless, certain chemicals continue to be obtained from coal by traditional routes, and an interest in coal-based chemicals has been maintained in academic and industrial research laboratories. Much of the recent activity in coal conversion has been focused on production of synthetic fuels, but significant progress also has been made on use of coal as a chemical feedstock (see Coal CONVERSION processes). 

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