Single feedstock

Phase I biorefinery (single feedstock, single process and single major product)... 

A practical approach we have used in the past is to define a simple empirical model for the decomposition of feedstock (single or mixed feeds). Then yields, product gas composition, expansion on cracking, partial pressure, and so forth, are all calculated by using a back-up program which relates yields to decomposition or other internal measures of severity and to the other conditions of cracking (reaction time, average partial pressure). 

If air is used, then a single pass with respect to each feedstock is used and no recycle to the reactor (Fig. 10.4a).-Thus the process operates at near stoichiometric feed rates to achieve high conversions. Typically, between 0.7 and 1.0 kg of vent gases are emitted per kilogram of dichloroethane produced. ... 

In a single stage, without liquid recycle, the conversion can be optimized between 60 and 90%. The very paraffinic residue is used to make lubricant oil bases of high viscosity index in the range of 150 N to 350 N the residue can also be used as feedstock to steam cracking plants providing ethylene and propylene yields equal to those from paraffinic naphthas, or as additional feedstock to catalytic cracking units. 

In a single stage with liquid recycle, total conversion to products lighter than the feedstock is possible. The yield of kerosene plus diesel is between 70 and 73 weight %. 

If a linear mbber is used as a feedstock for the mass process (85), the mbber becomes insoluble in the mixture of monomers and SAN polymer which is formed in the reactors, and discrete mbber particles are formed. This is referred to as phase inversion since the continuous phase shifts from mbber to SAN. Grafting of some of the SAN onto the mbber particles occurs as in the emulsion process. Typically, the mass-produced mbber particles are larger (0.5 to 5 llm) than those of emulsion-based ABS (0.1 to 1 llm) and contain much larger internal occlusions of SAN polymer. The reaction recipe can include polymerization initiators, chain-transfer agents, and other additives. Diluents are sometimes used to reduce the viscosity of the monomer and polymer mixture to faciUtate processing at high conversion. The product from the reactor system is devolatilized to remove the unreacted monomers and is then pelletized. Equipment used for devolatilization includes single- and twin-screw extmders, and flash and thin film evaporators. Unreacted monomers are recovered for recycle to the reactors to improve the process yield. 

Plasma fractionation is unusual in pharmaceutical manufacturing because it involves the processing of proteins and the preparation of multiple products from a single feedstock. A wide range of unit operations are utilized to accompHsh these tasks. They are Hsted in Table 3 some are common to a number of products and all must be closely integrated. The overall manufacturing operation can be represented as a set of individual product streams, each based on the processing of an intermediate product derived from a mainstream fractionation process (Fig. 1). 

One of the conveniences afforded by curing PPS is that a single uncured feedstock can give rise to an entire family of cured polymers. The flow rates, ie, the extent of cure, of the cured polymers are optimized for specific appHcations. Table 1 shows typical melt flow values of cured PPS polymers for various types of appHcations. 

Steam-Reforming Natural Gas. Natural gas is the single most common raw material for the manufacture of ammonia. A typical flow sheet for a high capacity single-train ammonia plant is iadicated ia Figure 12. The important process steps are feedstock purification, primary and secondary reforming, shift conversion, carbon dioxide removal, synthesis gas purification, ammonia synthesis, and recovery. 

Transportation and Distribution Cost. Although much ammonia serves as feedstock for other processes, the largest single use in the United States is as a direct appHcation fertiliser without further processing. This direct appHcation consumption is mosdy in the farm belt and ammonia produced in the Gulf Coast states is shipped to terminal faciUties and then distributed by retail outlets to the farmer. 

By virtue of the nature of the paraffinic feedstocks readily available, commercial chlorinated paraffins are mixtures rather than single substances. The degree of chlorination is a matter of judgment by the manufacturers on the basis of their perception of market requirements as a result, chlorine contents may vary from one manufacturer to another. However, customers purchasing requirements often demand equivalent products from different suppHers and hence similar products are widely available. 

CycE 3.nd the variable manufacturing expense per unit of raw material will be The unit of raw material may be either a single material or a mixture of several components. I. Leibson and G. A. Trischman [Chem. Eng., 78, 69-74 (May 31, 1971)] showed the effects on manufacturing expenses of alternate feedstocks having different compositions and costs for producing the same produces. 

Normal paraffins in this range are important intermediates for alkylating benzene for synthetic detergents production (Chapter 10). They are also good feedstocks for single-cell protein (SCP). 

The regenerator design, either single-stage or two-stage, should provide uniform catalyst regeneration, increase flexibility for processing a variety of feedstocks, and minimize thermal and hydrothermal deactivation of the catalyst. 

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