Operating economics

In electrolytic processes, the anode is the positive terminal through which electrons pass from the electrolyte. Anode design and selection of anode materials of constmction have traditionally been the result of an optimisation of anode cost and operating economics, in addition to being dependent on the requirements of the process. Most materials used in metal anode fabrication are characteristically expensive use has, however, been justified by enhanced performance and reduced operating cost. An additional consideration that has had increasing influence on selection of the appropriate anode is concern for the environment (see Electrochemical processing). 

The selection of a particular type of reduction depends on technical feasibiUty and the economics of the process as well as on physicochemical considerations. In particular, the reducing agent should be inexpensive relative to the value of the metal to be reduced. The product of the reaction, RX, should be easily separated from the metal, easily contained, and safely recycled or disposed of. Furthermore, the physical conditions for the reaction should be such that a suitable reactor can be designed and operated economically. 

No SCR catalyst can operate economically over the whole temperature range possible for combustion systems. As a result, three general classes of catalysts have evolved for commercial SCR systems (44) precious-metal catalysts for operation at low temperatures, base metals for operation at medium temperatures, and 2eohtes for operation at higher temperatures. 

Interest in the application of turboexpanders turbine to FCC unit is very high, and deservedly so. The power recovery turboexpander offers practical improvement in FCC unit operating economics. Modern designs that encompass the entire system have fully overcome problems and concerns that may have existed decades ago. Expander metallurgy is available to vastly reduce erosion rates experienced when... 

Favorable operational economics and good management practices require high levels of control of the ozonation system. Depending on the specific process of ozone applications, plant size, and design philosophy, the control system may be simple or complex. The trend in Europe is toward highly sophisticated and centralized control. 

With the operating economics of pumping system, such as the water industry networks receiving attention, it is of... 

The ultimate goal of process development is to achieve feasibility where it is possible to produce amino adds on a large scale at a production cost per kg of amino add comparable to, or cheaper than, the processes currently used by other companies. If we presume that the technical performance (fermentation and recovery) are sorted out on a laboratory scale and scaling up looks promising, then it is time to find out whether it is possible to operate economically on a large scale. 

The description of the association of heterocychc chemistry and microwave irradiation has also shown that performing microwave-assisted reactions should be considered with special attention. A few of these considerations can be applied generally for conducting microwave-assisted reactions and include the following (a) the ratio between the quantity of the material and the support (e.g., graphite) or the solvent is very important (b) for solid starting materials, the use of solid supports can offer operational, economical and environmental benefits over conventional methods. However, association of liquid/solid reactants on solid supports may lead to uncontrolled reactions which may result in worse results than the comparative conventional thermal reactions. In these cases, simple fusion of the products or addition of an appropriate solvent may lead to more convenient mixtures or solutions for microwave-assisted reactions. 

The various examples discussed have shown that electronics play their part in all basic functions of state-of-the-art washing machines and that it would be difficult to imagine a future without them. Above all, electronic control is crucial if washing machines are to be operated economically. Fig. 3.15 gives a final summary of the most important points. 

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 ... 

The operating economics are characterized primarily by the recovery of oxygen. Recovery is defined as the quantity of O2 delivered by the process divided by the quantity of O2 that was present in the feed air. 

In an endothermic reaction, the reactant temperature will fall as reaction proceeds unless heat is supplied from an external source. With a highly endothermic reaction, it may be necessary to supply a considerable amount of heat to maintain a temperature high enough to provide a rate of reaction and equilibrium conversion which are large enough for the process to be operated economically. Under these circumstances, the rate of heat transfer may effectively determine the rate of reaction and so dominate the problems involved in the reactor design. 

According to the vendor, the Ultimate Solution can only operate economically in large treatment systems. The vendor supplied cost estimates for treating municipal solid waste, industrial hazardous waste, radioactive waste, and hospital solid waste at various treatment rates and... 

The location of several modules at a single site would achieve many of the operating economics of a single larger plant. 

If unreacted A can be recovered from the product mixture at low cost and then recycled, the relative yield is the more significant, and the reactor can probably be operated economically at quite a low conversion per pass. If it cannot be recovered and no credit can be allotted to it, the operational yield is the more relevant, and the reactor will probably have to operate at a high conversion per pass. 

In addition to process design it is essential to design the drinks factory such that it can be operated economically and cleanly. It is also important that its design is of minimal capital cost and consistent with production to desired quality standards. 

Many of the uncertainties shrouding the development of this technology could be eliminated if we could provide actual investment costs, operating economics, environmental information, etc. However, without federal assistance—particularly some type of financial incentive—it appears unlikely that any commercial High-Btu Gas plants will be built. The federal role could be to assist the private sector in capital formation spreading the financial risk appropriately among project beneficiaries—be it industry, gas users or the public. 

Starch recovery, as presently practiced, depends on a continuous supply of fresh root. Hence, factories are located close to the root producing areas. In Brazil, the processing season can be as short as six months. In Thailand, continuous processing is possible, although some starch producers are known not to operate during part of the rainy season when the starch content of cassava root is low and operating economics are less favorable. 

Multiple-step variable-speed fan control, type d. is best applied with steam-turbine drives. In aplant with ac auxiliary motor drives, slip-ring motors with damper integration must be used between steps, making the installation expensive. Although dc motor drives would be less costly, few power plants other than marine propulsion plants have direct current available. And since marine units normally operate at full load 90 percent or more of the time, part-load operating economics are unimportant. If steam-turbine drive will be used for the fans, plot the power-input curve LMD, using data from the fan manufacturer. 

The models of components are joined together so that it is possible to simulate the whole Ecoflame-system Fig. 2). In this paper the model of the hoiler is not described. However, some computational results concerning operational economics are shown. 

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