Input feedstock

A chemical plant is an arrangement of processing units (reactors, heat exchangers, pumps, distillation columns, absorbers, evaporators, tanks, etc.), integrated with one another in a systematic and rational manner. The plant s overall objective is to convert certain raw materials (input feedstock) into desired products using available sources of energy, in the most economical way. 

The ABE fermentation is an established industrial process but has, over the last century, struggled to compete with fluctuating commodity prices that affect both the input feedstock cost and the product pricing. These factors have a huge impact... 

Industries that consume finished fibers include weaving mills that produce febrics and textiles from all manner of fibers, including glass, basalt, and carbon. These fibers are then used accordingly, for clothing, composites, or other uses. Cordage manufecturers use finished fibers as an input feedstock to produce every type of cordage, from fine thread to coarse rope. 

The heat loss due to heating up input feedstock was calculated as ... 

The pretreatment stage usually generates an amount of residue which will not enter the fermentation process and is well above 10 wt% of the input feedstock. In the case of low contamination of the feedstock, these residues are still predominantly made of materials of biogenic origin, potentially suitable for composting. 

Before designing a process scheme it is necessary to know the specification of the raw material input (or feedstock) and the specification of the enc/procfucf desired. Designing a process to convert fluids produced at a wellhead into oil and gas products fit for evacuation and storage is no different. The characteristics of the well stream or streams must be known and specifications for the products agreed. 

The quality and yield of carbon black depends on the quaUty of the feedstock, reactor design, and input variables. The stmcture is controlled by the addition of alkaU metals to the reaction or mixing 2ones. Usual practice is to use aqueous solutions of alkaU metal salts such as potassium chloride or potassium hydroxide sprayed into the combustion chamber or added to the make oil in the oil injector. Alkaline-earth compounds such as calcium acetate that increase the specific surface area are introduced in a similar manner. 

A typical reactor operates at 600—900°C with no catalyst and a residence time of 10—12 s. It produces a 92—93% yield of carbon tetrachloride and tetrachloroethylene, based on the chlorine input. The principal steps in the process include (/) chlorination of the hydrocarbon (2) quenching of reactor effluents 3) separation of hydrogen chloride and chlorine (4) recycling of chlorine to the reactor and (i) distillation to separate reaction products from the hydrogen chloride by-product. Advantages of this process include the use of cheap raw materials, flexibiUty of the ratios of carbon tetrachloride and tetrachloroethylene produced, and utilization of waste chlorinated residues that are used as a feedstock to the reactor. The hydrogen chloride by-product can be recycled to an oxychlorination unit (30) or sold as anhydrous or aqueous hydrogen chloride. 

Converting Heat to Work. There has been a historic bias in the chemical industry to think of energy use in terms of fuel and steam (qv) systems. A more fundamental approach is to minimise the input of work potential embedded in the fuel and feedstock, as well as work purchased direcdy as electricity. Steam is really just a medium of exchange, like money in an economy. 

By cooling the gas is condensed and then available as hydrocarbon feedstock for other processes (some 85% of the MPW input). The light hydrocarbon gas (15% of the MPW input) that remains after cooling is compressed, reheated and returned to the reactor as fluidising gas. It can also be used as a fuel for the cracking process, though other recovery options are being studied as well. 

As indicated in the former chapter most processes for feedstock recycling have limitations with regard to the maximum allowable chlorine input. This makes those processes problematic for the treatment of PVC-rich MPW. Hence, a number of initiatives has been developed for the treatment of PVC waste. All these processes seek to recover the chlorine present in PVC in a usable form (HCl or a saleable chloride salt). The processes include ... 

Most industrial hydrogen is manufactured by the following hydrocarbon-based oxidative processes steam reforming of light hydrocarbons (e.g., NG and naphtha), POx of heavy oil fractions, and ATR. Each of these technological approaches has numerous modifications depending on the type of feedstock, reactor design, heat input options, by-product treatment,... 

Thus, by considering the overall mass balance, i.e., looking at the inputs and outputs of the process, one can gain many insights into a process and also identify opportunities for C02 emissions reduction and enhancing feedstock utilization. 

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