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Economic requirements

The economic factors must be considered in every application. It is important to find a technique that will meet both the technical and economical requirements. In short, pollution control costs depend on the system characteristics and the application. Some cost equations that generalize the economics of the managing systems are available in the literature. Most of these equations give rough estimates and have an accuracy of only about 30% to 50%. For a comprehensive cost comparison of different units, a detailed cost analysis based on the equipment tender proposals and the special characteristics of the project is necessary. [Pg.1255]

On the basis of this better performance of the Pall ring, a smaller diameter tower must be selected and the tower reevaluated based on the new mass flow rates with this packing. The economics require that the higher packing cost, smaller tower diameter, new total packing volume, and tower pressure drop be considered. [Pg.367]

In a particular service situation, other considerations may preclude some approaches to prevention for example, weight, strength or economic requirements may dictate the use of an alloy susceptible to cracking. More-... [Pg.1192]

Manufacturing economics require that many devices be fabricated simultaneously in large reactors. Uniformity of treatment from point to point is extremely important, and the possibility of concentration gradients in the gas phase must be considered. For some reactor designs, standard models such as axial dispersion may be suitable for describing mixing in the gas phase. More typically, many vapor deposition reactors have such low L/R ratios that two-dimensional dispersion must be considered. A pseudo-steady model is... [Pg.426]

Today we face a different challenge. Environmental pressure is pushing away from S)mthetic or petro-chemically derived products, while economic factors are pulling back from often more expensive "green" options. This paradox is what fuels research into materials and products whose properties fulfill environmental and economic requirements. [Pg.228]

Physical, Technical and Economical Requirements on Phase Change Materials... [Pg.260]

A schematic diagram of the liquid solvent extraction process is illustrated in Figure 1. Where the production of liquid hydrocarbons is the main objective an hydrogenated donor process solvent is used, whereas in the production of needle coke this is not necessary and a coal derived high boiling aromatic solvent may be used (e.g. anthracene oil). An essential economic requirement of the process is that a high extraction yield of the coal is obtained and this will depend upon the coal used and the digestion conditions. [Pg.115]

In other words the economic area of greater Germany is too small to satisfy the military economic requirements as to mineral oils. The new and successful contacts with southeastern Europe show us that the only hopeful possibility to insure supplies for the mineral-oils economy completely for many years is by securing this area by means of the Wehrmacht. [Pg.252]

To plan the tests correctly and economically requires knowledge of the performance of the material at the start. It is easy to select temperatures which lead to failure in times either too short to satisfy the standard, or too long to wait for. Adding a contingency for this adds considerably to the cost of testing. [Pg.156]

Effective design of a remediation system for dissolved hydrocarbons in groundwater requires consideration of more than only the effectiveness of the technological process involved. At many sites a variety of techniques are capable of completing the cleanup. However, design of a project that is efficient in all aspects — technically, in terms of time, and economically — requires an evaluation of the entire life cycle of the project from inception to closure. Typically, at sites where remediation is expected to continue over a 4-year project life, operation and maintenance account for between 50 and 80% of the total project cost. These percentages increase each year thereafter. The principal components of operation and maintenance are power, labor, and parts. Identification and quantification of these components are critical to the overall cost of a project. [Pg.344]

Catalysis Issues in SOFC Catalytic processes play in important role in the operation of in particular, the SOFC anode and cathode, and the major challenges for the further development of SOFC towards a commercial project are largely related to improving catalytic activity and robustness. The critical technical issues for SOFC are reliability and lifetime, while economic requirements impose low manufacturing and materials costs. [Pg.328]

Each category comprises both mass-production and high-tech products, with stringent economic requirements for the former and specific performances for the latter. [Pg.110]

Thermoplastics are used for insulation and housings, allowing a broad choice according to the technical and economic requirements, for example ... [Pg.114]

Launching new polymers of medium-range performance is a difficult operation economically, as proved by the case of the aliphatic polyketones. New polymer families are rarely marketed but there are some examples where they provide improved processing performances, which is a particularly needed property to satisfy economic requirements. Modification of existing polymers is also an interesting route. Let us quote some examples ... [Pg.843]

Obviously one of the important economic requirements for electroplating industry is that as much material is plated in as short a time as possible. Therefore industrially the process is run at high currents for maximum discharge rate (Faraday s first law). However higher discharge rates mean that the surface concentration of the ions at the... [Pg.232]

In summary, an ozonation system from a customer s viewpoint has to meet the following technical and economical requirements ... [Pg.34]

Modification of some design parameters, Figure 8.13(c), then rerating the design to meet thermal and hydraulic specifications and economic requirements. [Pg.200]

Bioprocess economics require the engineer or scientist to be able to quickly recognize limiting technical parameters that are likely to be encountered upon scale-up. Processing schemes that minimize operational... [Pg.232]

Arrangement of membranes into long or short cells has no bearing upon cost. The economic requirement on design is only that it ensure the optimum current density at every point in the cell. A technical requirement, however, imposes a further restriction upon design that the current density be maintained in the neighborhood of the diffusion limiting current. ... [Pg.231]

User requirement specifications cover more aspects than only the GMP requirement, because the URS is not written only for the validation procedure in fact, a URS is a very important project document covering technical as well as economic requirements of the technical system. Pharmaceutical manufacturing departments not only check the GMP aspects of a system additionally, following good engineering practice they will review the technical and economic aspects of a technical system. Obviously, the more experience a company gains, the more comprehensive a URS become. Past experiences such as project faults, inefficient technical systems, and bad commissioning can be included in a URS. [Pg.488]

These and further economic requirements have dictated the trend towards reducing the reactor size for a given thermal power. In order to achieve an adequate increase of the plasma power density higher values of P (Eq. 8) have to be used (Eq.9). A convenient way to achieve this requirement is to use plasmas of a noncircular cross section (Fig. 7). [Pg.58]

For a fiber with a length of 1 km and with a core of 50 um diameter, a total of about 5 g of oxide material is needed. In order to be economical the process should be capable of a deposition rate of 0.1-1.0 g/min at least. It is clear therefore that the rate had to be some orders of magnitude higher than the rates used by earlier investigators in order to fulfill the economic requirements. [Pg.114]


See other pages where Economic requirements is mentioned: [Pg.509]    [Pg.45]    [Pg.71]    [Pg.265]    [Pg.139]    [Pg.109]    [Pg.122]    [Pg.261]    [Pg.379]    [Pg.93]    [Pg.47]    [Pg.35]    [Pg.154]    [Pg.20]    [Pg.52]    [Pg.698]    [Pg.81]    [Pg.72]    [Pg.3]    [Pg.207]    [Pg.509]    [Pg.200]    [Pg.426]    [Pg.488]    [Pg.239]    [Pg.402]    [Pg.80]   
See also in sourсe #XX -- [ Pg.20 ]




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