Economic comparison with

The future for these technologies is uncertain. Economic comparisons with fluorspar-based processes indicate that as long as fluorspar suppHes remain abundant, there is Httle justification to proceed with such processes. 

Deneuve E, Roncato JP (1981) Thermochemical or hybrid cycles of hydrogen production- technico-economical comparison with water electrolysis. Int J Hydrogen Energy 6 9-23... 

In analogy to photovoltaic and photoelectrochemical devices aimed at electricity production (see Sorensen, 2004), efforts have been made to modify the devices in question to deliver hydrogen directly rather than electricity. Of course, there is always the alternative to convert the electricity to hydrogen in a second step, e.g. by conventional electrolysis. This is conveniently used as a backstop technology for economic comparison with new proposals. 

Shinnar, Reuel, et al. Thermochemical and hybrid cycles for hydrogen production A differential economic comparison with electrolysis. ... 

A monomer of nyion-11, commercialized by ATO Chem, under the name of Riisan, U-aminoundecanoic add is prepared from castpr. oil. Hence its manufacture does not strictly form part of the field of petrochemicals. It is nevertheless discussed here to provide an example of synthesis from biomass, and for technico-economic comparisons with nylon-12, which has comparable properties, and whose monomer is of petrochemical origin., "... 

In summary, we have described an anaerobic process for singlecell protein from crude carbohydrates. The inhibitory by-products are simultaneously converted into methane. Mass transfer limitations can be avoided by using microfiltration rather than dialysis. Further study of the kinetics and improvements in yield will be necessary in order to make an economic comparison with other processes for single-cell protein. 

Economic comparison with traditional phenol processes shows the commercial significance of this newest process. ... 

Assume that further detailed work has located a new plant site at Natchez, Mississippi. Then a detailed economic comparison with the existing plant site at Parkersburg is made. The summary of results without itemized detail figures under investments and costs is listed in Table 7-3. These results are presented in report form to company management for a final decision. From an investment standpoint, the plant should be located at the existing site at Parkersburg, West Virginia. 

In practice, it is necessary to consider each electrolytic process on its merits and the economic comparison with any competing metal reduction process is sometimes favourable and on other occasions unfavourable. It has not generally been possible to bring the cost of rare metal production by electrolysis within striking distance of the bare cost of the electric power used, since substantial subsidiary materials costs arise and the maintenance and replacement rate of equipment is high. 

Since the area immediately adjacent to the pilot represented the average reservoir conditions of the entire field, the polymer flood pilot performance was scaled up to the full field basis so that an economic comparison with the actual waterflood operation could be made. A summary of this comparison is shown in Table 1. 

Erlach, B., Wirth, B., Tsatsaronis, G., 2011. Co-production of electricity, heat and biocoal pellets from biomass a techno-economic comparison with wood pelletizing. In Proceedings of World Renewable Energy Congress (Bioenergy Technology), Sweden. 

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... 

More up-to-date data of this process are employed in a study by Rase (Fixed Bed Reactor Design and Diagnostics, Butterworths, 1990, pp. 275-286). In order to keep the pressure drop low, radial flow reactors are used, two units in series with reheating between them. Simultaneous formation of benzene, toluene, and minor products is taken into account. An economic comparison is made of two different catalysts under a variety of operating conditions. Some of the computer printouts are shown there. 

Modifications of the existing plants to sequestrate and dispose of the CO2 will lead to a reduction in net thermal efficiency and an increase in capital cost both these features will lead to increased cost of electricity generation. Whether these plants will be economic in comparison with conventional plants of higher efficiency and less capital cost will be determined by how much the conventional plants will have to pay in terms of a carbon tax. 

Chiesa and Con.sonni [1,3] have made detailed studies of how a CO2 tax would affect the economic viability of several of these cycles when a tax and CO2 removal are introduced. Fig. 8.27 shows their results on the cost of electricity for natural gas-fired plants plotted against the level of a carbon tax (in c/kg CO2 produced), for two of the novel cycles studied here, in comparison with an existing CCGT plant with natural gas firing. 

A suction bell on the inlet of a vertical pump (or the inlet pipe of the suction side of a horizontal pump) is not necessary as far as pump or sump operation is concerned. If a bell is omitted, the entrance losses due to flow will be higher ith only a straight pipe, and this must be considered in pump operation. An economic comparison vsill help decide the value of the bell. Strainers should not be placed on suction bells unless this is the only arrangement. Inlet water should be screened with trash racks, bars and screens to keep the sump free of debris. 

Although these units find initial application in areas of limited water, they have not been limited to this situation. In many instances they are more economical than cooling tower systems and have been successfully applied in combination with cooling towers (see Figure 10-184). Economic comparisons should include such items as tower costs, basin, make-up facilities, water treatment, pumps for circulation, power supply, blow down, piping, etc. For small installations of air-cooled units, they should be compared... 

Briquettes of CaO with 5-20% excess powdered A1 are heated under vacuum to 1170°C in a Ni-Cr steel (15/28) retort in which the Ca vapor, produced by reduction of solid CaO by A1 vapor, is condensed in a zone at 680-740 C. Any Mg impurity is condensed in a zone at 275-350°C a mixture of the two metals condenses in an intermediate zone. The A1 content of the product can be reduced by passing the metal vapor, before it condenses, through a vessel filled with solid CaO. The adaptation of the FeSi thermal reduction process for Mg production (see 7.2.3.2.1) to Ca manufacture has also been described but is not economically viable in comparison with the above process. The thermal reduction of CaO with carbon has been proposed as for Mg production, however, the reversibility of the equilibrium ... 

Economic data relating to amisulpride are very few, despite the longstanding availability of this dmg in France. There appears to be only one published economic evaluation—a comparison with haloperidol (Souetre et al, 1992). In this French study, direct medical... 

Economics. Comparison of the material and energy balance for our process and the cobalt-based BASF higher olefin process (8), we foimd that our process reduced the capital investment required by over 50% due to the fact that we require far fewer unit operations, and because the operating pressure is much lower. In sutmnary, the thermomorphic solution developed by TDA allows easy catalyst recycle, which, when coupled with the lower pressure operation possible with Rh catalysts (compared to the cobalt-based process) lowers both capital and operating costs for current oxidation (oxo) plants of similar capacity. 

Another important consideration pertains to the metal content of the deposit. A deposit with a content of iron of about 20% can have little value as an iron ore since there are several deposits with 30-50% iron. Earlier, a copper ore with a minimum of 5% copper was regarded or accepted as a copper ore. However, today, thanks to advancements in technology, rocks with as little as 0.5% copper are mined and processed economically despite the fact that the price of copper, in comparison with those of some other metals, might be showing a downward trend. It is possible that in the future, other resources, which are not considered to be worth exploiting today (such as the manganese nodules or the clays), would become acceptable ores for manganese, copper, nickel, cobalt, and aluminum. 

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