Costing processes

High demands are placed on the substrate material of disk-shaped optical data storage devices regarding the optical, physical, chemical, mechanical, and thermal properties. In addition to these physical parameters, they have to meet special requirements regarding optical purity of the material, processing characteristics, and especially in mass production, economic characteristics (costs, processing). The question of recyclabiUty must also be tackled. 

Solvent extraction is a relatively high cost process, owing to the specialty organic extractants required and the expenses of recovery and storage of... 

Manufacturing. Almost all the THE in the United States is currendy produced by the acid-catalyzed dehydration of 1,4-butanediol [10-63-4]. Only one plant in the United States still makes THE by the hydrogenation of furfural (29). Du Pont recendy claimed a new low cost process for producing THE from / -butane that they plan to commercialize in 1995 (30—32). The new process transport-bed oxidizes / -butane to cmde maleic anhydride, then follows with a hydrogen reduction of aqueous maleic acid to THE (30). 

Production cost Process selection Machine tools Operator skill Tooling, fixtures inspection precision Assemblability Scrap and rework... 

SCR units require handling, storage, and continuous injection of the reducing agent. The temperature level is critical because the SCR operates in a narrow temperature range between 550°-750°F (260°-399°C), and thus an exchanger is necessary to cool the exhaust stream. This leads to a complicated and costly process system that must be added to the engine exhaust. 

Developing new chemical engineering design tools to deal with the multiple objectives of minimum cost process resilience to changes in inputs minimization of toxic intermediates and products and safe response to upset conditions, start-up, and shutdown. 

These chemicals have all been produced since the beginning of the chemical industry by various and sometimes changing processes. When process changes were made, it was almost always for economic reasons, that is, to make products at lower cost. It seems unlikely that still lower cost processes will be developed, but there may be future process changes for some of these chemicals because of environmental concerns. 

The cost price of a bulk chemical is determined primarily by the cost of raw materials, which could represent > 80% of the total costs. Process development/improvement in bulk chemicals is, hence, focused on decreasing these variable costs, e.g. for a product with a volume of 100,000 tpa and a raw materials quote of 2/kg, 1% increase in yield corresponds to savings of 2 million per annum. In fine chemicals, in contrast, emphasis is placed on the reduction of fixed costs, which are relatively high, by process simplification. For example, for a product with a volume of 100 tpa and fixed costs of 40/kg, if the volume yield (amount produced per unit reactor volume) is doubled, this corresponds to savings of 2 million per annum. 

Rhodium catalyzed carbonylations of olefins and methanol can be operated in the absence of an alkyl iodide or hydrogen iodide if the carbonylation is operated in the presence of iodide-based ionic liquids. In this chapter, we will describe the historical development of these non-alkyl halide containing processes beginning with the carbonylation of ethylene to propionic acid in which the omission of alkyl hahde led to an improvement in the selectivity. We will further describe extension of the nonalkyl halide based carbonylation to the carbonylation of MeOH (producing acetic acid) in both a batch and continuous mode of operation. In the continuous mode, the best ionic liquids for carbonylation of MeOH were based on pyridinium and polyalkylated pyridinium iodide derivatives. Removing the highly toxic alkyl halide represents safer, potentially lower cost, process with less complex product purification. 

One very basic factor worth listing perhaps in the very beginning is the necessity of size reduction. It is a costly process not only in terms of money, but also in terms of energy. It may be more advantageous to buy already sized material or to alter some other stage of processing, in order to avoid the size reduction operation altogether. 

DAF is controlled under laminar hydraulic flow conditions using a very small volume of air flow amounting to about 1 to 3% of the influent groundwater flow. DAF only requires 3 to 5 min of detention time therefore it is a low-cost process for the decontamination of groundwater. 

From the detail shown above, it is easy to see why drag discovery and development is such a costly process. One drag in every 5000-10000 entering preclinical studies makes it to the clinic. A recent estimate put the cost of bringing one drag to market as US 500 million [75], and up to 70% of that cost is associated with compound failures in these studies. DiMasi et al. have suggested that reductions... 

There is currently great commercial interest in plastic alternatives to conventional silicon-based components in electronic devices. Polymeric architectures offer flexible, low-cost, processable materials for this lucrative global market, and can be designed with more emphasis on device performance. The principal goals of improved band filling, dimensionality and new conductance mechanisms remain the same, and provide a subtly different challenge to the materials chemist. 

There is already much practical experience available on the osmotic treatment itself. To fulfill consumer, industrial, and environmental expectations, however, some problems remain to be solved. Osmotic treatments have been applied frequently as a low-cost processing method neglecting process optimization, but the current interest in this technique and the development of industrial applications on a large scale demand controlled processes. For successful process control and optimization, efforts have to be made in the following key areas (Figure 2). 

Water atomization is intrinsically a high volume, low cost process. Therefore, it is generally more cost-effective compared to other commercial atomization methods. However, powder purity,... 

MTBE is a well known enhancer of the number of octanes in gasoline and as excellent oxygentated fuel additives that decrease carbon monoxide emissions. Therefore, MTBE has been one of the fastest growing chemicals of the past decade. MTBE is produced by reacting methanol with isobutylene from mixed-C4 stream liquid phase over a strong acid ion-exchange resin as catalyst. An excess of methanol is used in order to improve the reaction conversion. This excess has to be separated from the final product. The pervaporation technique, more energy efficient and with lower cost process, has been proposed as alternative to distillation [74],... 

The large volumes of PET produced for fibers, films, blow-molding and injectionmolding grades have led to large-scale, low-cost processes for making terephthalic acid, and to a lesser degree, dimethyl terephthalate (DMT) (2). 

A review of alloy and process development of the TiAl alloy has been published by Wu (2006). The main conclusions are that TiAl development is now relatively mature the major requirement is the promotion of low cost processing coupled with the supply of high-quality raw material the future application of net shape powder process routes could be cost effective both for complex large components and for some small components. Special attention is dedicated in this review to alloys based on Ti-(45—46)Al-(5-8)Nb (at.%) and Ti-48Al-2Cr-2Nb (at.%). 

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