Cost-Effective Selection

This generally falls somewhere between these extremes and includes consideration of many other factors. In most instances, there will be different alternative materials that may be considered for a specific application. Calculation of true long-term costs requires estimation of the following  

It should be realized that the costs of processed products, such as sheet, plate, sections, and forgings will be much higher than ingot. Every process and every heat treatment will give added value and increase the final material cost. Also the process of alloying will mean that, generally, the costs of alloys will be higher than those of unalloyed metals (see Tables 4.6 and 4.7) 

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In practice, adequate and cost-effective selection of monitoring wells requires some prior basic knowledge of the main characteristics of the aquifer system under consideration, including at minimum some information on ... 

There would seem to be a need for a new cost-effective, selective, and high-capacity adsorbent for the removal of P2M- Hypercrossfinked networks are undoubtedly prospective materials. 

Various types of FBDs have been studied, developed, and operated in many industrial processes according to the respective process, product, operational safety, and environmental requirements. It is important to become familiar with the specific characteristics of different fluidized bed types in order to make a logical and cost-effective selection. It should be noted that in many instances, several different types may provide similar performance at the same cost. 

From an industrial perspective, the use of carbohydrate-active enzymes as cost effective, selective catalysts of biomass hydrolysis has been growing steadily over the last century (5). In particular, carbohydrases play key roles in the starch processing, animal feed, textile, and pulp and paper industries (5-7) (Table 1). The observation that enzymatic starch processing alone accounted for nearly 10% of the U.S. 1.4 billion enzyme market (1998 values) further underscores the importance of these catalysts (6). The use of (hemi)cellulose-degrading enzymes to saccharify biomass as a precursor to biofuels production and other bioreflnery purposes are of particular contemporary interest in the quest to reduce fossil fuel dependence (5,8,9). 

It has been shown that the machine requires a separator device, which is automated to some extent. The cost-effective selection has already been partly covered by the decision to have two levels of separation, rather than rating the maximum system flow at the lowest level. 

One of the most cost effective forms of maintenance is to train the operators to visually Inspect the equipment on a daily basis. Careful selection of staff, appropriate training and incentives will help to improve what is often called first-line maintenance. 

In an economic comparison of these three common abatement systems, a 1991 EPA study (58) indicates extended absorption to be the most cost-effective method for NO removal, with selective reduction only matching its performance for small-capacity plants of about 200—250 t/d. Nonselective abatement systems were indicated to be the least cost-effective method of abatement. The results of any comparison depend on the cost of capital versus variable operating costs. A low capital cost for SCR is offset by the ammonia required to remove the NO. Higher tail gas NO... 

HP Alkylation Process. The most widely used technology today is based on the HE catalyst system. AH industrial units built in the free world since 1970 employ this process (78). During the mid-1960s, commercial processes were developed to selectively dehydrogenate linear paraffins to linear internal olefins (79—81). Although these linear internal olefins are of lower purity than are a olefins, they are more cost-effective because they cost less to produce. Furthermore, with improvement over the years in dehydrogenation catalysts and processes, such as selective hydrogenation of diolefins to monoolefins (82,83), the quaUty of linear internal olefins has improved. 

In most cases volume requirement is the primary consideration for selecting the most cost-effective process. However, in many cases a lower volume process may be used during initial phases of a program and then be replaced by a higher volume process when the product has gained field acceptance. 

The combination of the cost model and the optimization method will then give an augmented model from which the allocation of the component tolerances are optimized for competitive results. Optimization methods have also been extended to include procedures that select the most cost-effective manufacturing process for each component tolerance in the assembly stack (Chase and Parkinson, 1991). 

If the critical impurities are known, then only a selected list of elements need to be examined, with some improvement in the cost effectiveness of the analysis. However, the list of elements to be included in the qualification analysis is often historical and related to the limitations of the analytical methods previously used for qualification rather than for technological reasons related to the end use of the metal. As a result, problems in application can arise for no obvious reason. The time and cost of extending the impurity list for GDMS analysis to include essentially all elements is minimal, considering the additional information gained. 

Flue gas treatment (FGT) is more effective in reducing NO, emissions than are combustion controls, although at higher cost. FGT is also useful where combustion controls are not applicable. Pollution prevention measures, such as using a high-pressure process in nitric acid plants, is more cost-effective in controlling NO, emissions. FGT technologies have been primarily developed and are most widely used in Japan. The techniques can be classified as selective catalytic reduction, selective noncatalytic reduction, and adsorption. 

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