Production costs From various feedstocks

Figure 6 indicates the ethylene production costs from various feedstocks in a U.S. billion lbs/yr ethylene plant based on premium valued by-products. If the predicted ethane and propane increases did in fact... 

Table 45. Ammonia production costs from various feedstocks in 1998 (600000 t/a)...

Simply looking at the feedstock prices or price ratios is iasufficient to accurately identify the most attractive feedstock because the values of all of the co-products and by-products must also be taken iato account. This is usually accompHshed by calculating the cost to produce ethylene with all other coproduct and by-product yields credited against the cost of ethylene. An example of the cost of ethylene is presented ia Table 4. The cash costs of ethylene from various feedstocks are compared for the months of July and November of 1991. Cash costs reflect all plant manufactufing costs except depreciation and are a measure of the out-of-pocket cash costs generated by the operation. 

Methanol and ethanol are alcohol fuels that can be produced from various renewable sources. Alcohol fuels are converted from biomass or other feedstocks using one or several conversion techniques. Both government and private research programs are finding more effective, less costly methods of converting biomass to alcohol fuels. Methanol was originally a by-product of charcoal production, but today it is primarily produced from natural gas and can also be made from biomass and coal. 

Determine the relative economics (cash cost and full cost) and available future supply of product from various regions and technologies. Consider potential technology developments and potential changes in relative prices of feedstocks. 

For the preparation of poly(isoprene), the monomer 2-methyl-1,3-buta-diene (= isoprene = IP) is required as feedstock. This monomer can be obtained by various condensation methods that utilize four principles to create the C5 skeleton. In the more modern process IP is obtained from the C5 cracking fraction which contains various double-bond containing hydrocarbons with 5 C-atoms (e.g. among other C5-compounds the fraction contains cyclopentadiene, various pentadienes and pentenes) [478]. The preparation of pure IP by either of these two routes is cost intensive. By the direct and selective polymerization of IP in the crude C5 cracking fraction the cost intensive isolation of pure IP is avoided. Thereby production costs for IR are considerably reduced [264,265]. The selective polymerization of IP in the crude C5 cracking fraction is achieved by the application of a NdP-based catalyst system. The latest patent of Michehn claims a process in which dehydrogenation of the C5 cut is applied prior to polymerization. In this way an IP-enriched C5-fraction is obtained which does not contain a high quantity of disubstituted alkynes, terminal alkynes and cyclopentadiene. The unpurified C5-fraction is used as the feedstock for polymerization [591,592]. 

This paper discussed the relative sensitivities of hydrogen cost to capital, feedstock, and utility prices for various different types of production processes, outlines some process selection criteria for different applications, and indicates what changes in process economics might be anticipated from new technical developments. 

The book critically compares the alternatives so that the most attractive options for petrochemical production can be identified for specific locations and conditions. For this purpose, technology capital and operating costs have been compared on the same basis (US Gulf location to a late 2007 cost base). From this, the production costs are estimated for various feedstock prices and compared to the traded prices of the products where appropriate. 

The use of waste materials as feedstocks for PHA biosynthesis constitutes a viable strategy for cost-efficient biopolymer production and supports various agro-industrial branches to overcome existing waste disposal problems. The subsequent Table 7.2 provides a compilation of selected carbon-rich waste streams that are reported to be potential feedstocks for microbial PHA production. Such carbon substrates that are of importance for human nutrition, like pure starch or edible oils from olives, soya or palm trees, are not included in this compilation. 

A methodology was described to assess the feasibihty of success in making commodity chemicals from renewable resources. The methodology uses a five-step process in the assessment. The first step is portfolio selection, and some of the key selection criteria are high theoretical yields from substrate, high market interest, and volume. The second phase involves initial economic screening and uses an economic criterion called the Fraction of Revenue for Feedstock (FRF). In this calculation, the cost of the feedstock is divided by the value of all the products, and the products that show the most promise are those where the fraction is smallest. This value takes into account the yields of the products derived from the various feedstock components. The third phase is a comparative analysis of bioprocessing routes that uses a raw material cost ratio, which... 

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