Factors Affecting Costs

Price fluctuations, 154 Probability distribution, 745-746 Process design deflnition of 2 development of 2-4, 14-19 Process engineering, deflnition of 2 Process synthesis, 112, 117-125 Product cosf estimation of 192-209 Production costs, factors affecting, 154-157... 

Statistical designs for experiments maximize information and reduce research time and costs. These techniques are less likely to miss synergistic factors affecting performance or product quaUty, minimize the element of human bias, eliminate less productive avenues of experimentation by taking... 

Two principal factors affected the U.S. sulfuric acid industry in the 1980s. The first was the increased availabiUty of recovered sulfur vs Frasch sulfur (see SuLFURREMOVAL AND recovery). This occurred because of environmental concerns and regulations forcing more sulfur to be recovered at refineries, power plants, etc. The effect of this change was that the cost of sulfur in the marketplace became driven largely by the cost of nonsulfur industries, rather than by the traditional discretionary sulfur producers, and tended to stabilize U.S. sulfur prices. 

The cost and price of sulfuric acid depend in large part on raw material cost and on freight costs. In many areas, the deUvered cost of sulfur is the most important factor affecting sulfuric acid pricing. By-product raw material, ie, SO2, costs at smelters are essentially zero, but the remote locations of many smelters make freight costs significant. Nevertheless, the nondiscretionary nature of smelter acid means that it must be sold if the smelter is to operate. 

Cost and Quality. Many factors affect catalyst support cost including which raw materials are used, the purity of the raw materials, the chemical processing steps required, the fabrication method used, the severity of calcination conditions, and the extent of the quaHty assurance procedure. In... 

As indicated, one of the factors affecting the selection of a filter is total cost of carrying out the separation with the selected machine. An important component of this cost item is the installed cost of the filter, which starts with the purchase price. 

Other considerations enter into the operation of the magnetic element, such as the desired range of leakage inductance for each winding, electrostatic shielding, etc. (see Appendix D). These factors affect the size and cost of the final magnetic element. 

It would be possible to remove all of the heat by pumping cold reflux from the distillate drum to the top of the tower and thus eliminate the cost of the pumparound circuit. Where more than one sidestream is withdrawn, however, it is usually economical to withdraw part of the heat in a pumparoimd reflux system farther down the tower. The following economic factors affect the choice ... 

Chase lists these factors affecting the overall costs ... 

Crucial factors affecting overall cost are the responsiveness to medication (for example, less than 70% of patients are lithium responders ), adherence to recommended treatment, and adverse events resulting from medication. A particular hazard of lithium treatment is the risk of rapid re-emergence of mania, which occurs in up to 50% of patients if the dmg is abruptly discontinued (see Cookson, 1997). Disappointingly, it has not been found that the introduction of widespread treatment with lithium has been associated with a reduction in the number of patients admitted and discharged from hospital with a diagnosis of mania. In order to achieve the best result with the available... 

The fourth factor affecting sampling frequency is efficiency, that is, to collect the minimum number of samples needed to address the key questions. The costs of collecting and analyzing samples are substantial, and the oversampling of a particular indicator would reduce resomces available for monitoring other indicators or other sites. 

Other factors affecting performance include the presence of toxic material, the redox potential, salinity of the groundwater, light intensity, hydraulic conductivity of the soil, and osmotic potential. The rate of biological treatment is higher for more permeable soils or aquifers. Bioremediation is not applicable to soils with very low permeability, because it would take a long time for the cleanup process unless many more wells were installed, thus raising the cost. 

Limited cost data are available for the construction and operation and maintenance (O M) of ET cover systems. The available construction cost data indicate that these cover systems have the potential to be less expensive to construct than conventional cover systems. Factors affecting the cost of construction include availability of materials, ease of installation, and project scale. Locally available soils, which are usually less costly than imported clay soils, are typically used for ET cover systems. In addition, the use of local materials generally minimizes transportation costs.3945... 

While the construction cost for an ET cover is expected to be less than that for a conventional cover, uncertainty exists about the costs for O M after construction. Several factors affecting the O M cost include frequency and level of maintenance (e.g., irrigation and nutrient addition), and activities needed to address erosion and biointrusion. In addition, when comparing the costs for ET and conventional covers, it is important to consider the types of components for each cover and their intended function. For example, it would generally not be appropriate to compare the costs for a conventional cover with a gas collection layer to an ET cover with no such layer. Additional information about the costs for specific ET cover systems is provided in project profiles, discussed in Section 25.9. 

Several factors affect the overall economics of PHA production. These include PHA productivity, PHA content, yield of PHA on carbon source, carbon substrate cost, and recovery method employed. Figure 1 shows the production costs of P(3HB) by various P(3HB) contents and P(3HB) productivities [29]. The effect of P(3HB) productivity on the production cost is only related to the cost of the fermentation equipment [18]. However, the P(3HB) content has multiple effects on the volume of the fermentation equipment and the recovery process [17,18]. The increase of P(3HB) yield on carbon source and the use of less expensive carbon substrates reduce the cost of carbon substrate [17, 29]. Development of an efficient recovery method, which will be different for each bacterium employed, is also important to overall economics of PHA production. When the actual fermentation processes employing many different re-... 

Extraction of PHA from plants is likely to be a major factor affecting the production cost of PHA from crops and, therefore, the economic viability of this approach. In contrast to production of PHA from bacterial fermentation, where the production system is designed to produce only PHA, an agricultural production of PHA is likely to be most viable only through the recovery of not only PHA but also all other useful components of the harvested crop, i.e., oil, proteins, and carbohydrates. This fact, combined with the lower level of PHA accumulation in plants in comparison to micro-organism, is likely to make PHA recovery from plants a challenging task. 

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