Solvent capital cost

If the feed, solvent, and extract compositions are specified, and the ratio of solvent to feed is gradually reduced, the number of ideal stages required increases. In economic terms, the effect of reducing the solvent-to-feed ratio is to reduce the operating cost, but the capital cost is increased because of the increased number of stages required. At the minimum solvent-to-feed ratio, the number of ideal stages approaches infinity and the specified separation is impossible at any lower solvent-to-feed ratio. In practice the economically optimum solvent-to-feed ratio is usually 1.5 to 2 times the minimum value. 

Cost. The cost of fresh solvent is reflected in the operating costs in the form of solvent make-up charges. Avoidance of solvent losses, and hence a reduction of operating costs, may be obtainable through better plant design which is usually associated with increased capital costs. 

Vapor Permeation Vapor permeation is similar to vapor perva-poration except that the feed stream for permeation is a gas. The futnre commercial viability of this process is based npon energy and capital costs savings derived from the feed already being in the vapor-phase, as in fractional distillation, so no additional heat inpnt wonld be req iired. Its foreseen application areas wonld be the organics recov-eiy from solvent-laden vapors and pollntion treatment. One commercial nnit was installed in Germany in 1989 (Ref. 26). 

Cascade adsorption will increase the initial capital cost you should evaluate whether the increase in solvent recovery justifies the added expense. 

When investigating the suitability of a particular resin-bound separations process, the following factors are often important (i) resin consumption (ii) solvent usage (iii) productivity-chemical, optical and volume yields (iv) total number of separations steps and (v) capital costs. For any particular process, these factors differ in their relative importance. However, when evaluating a new separations method it is useful to examine each of these factors. The nonchromatographic separation method... 

In the optimization of the solvent extraction process for the recovery of copper using LIX 64N, Robinson [77] described the eost funetion in terms of the sum of the operating and capital costs. The operating eosts were taken as resulting from losses of eopper and solvent ... 

The size of settlers is determined by the rate of phase disengagement, which, here, is a function of the solvent concentration of LIX 64N and the aqueous phase feed rate. The capital cost of extraction equipment is a function of the number of tanks, the size of the tanks, and the solvent inventory [9] ... 

Obviously, no solvent satisfies all these requirements, and the selection of a desirable solvent involves a compromise between these and other factors. When a preliminary selection has been made, a secondary screening can be performed based on simplified calculations of minimum energy requirement, since the capital costs for similar process configurations will not vary too much. 

Between 1993 and 1994, UVB technology was demonstrated at a solvent disposal site on the DOD s March Air Force Base in California. The capital cost for one UVB well was approximately 180,000. First and second year O M costs were approximately 75,000 and 42,000, respectively. The treatment costs for the trichloroethene-(TCE)-contamination was approximately 260 per 1000 gal of treated groundwater. The UVB well was designed to treat 1,000,000 gal per year (D188709, p. 9). 

In 1992, researchers developed an engineering and costing design for a fixed unit that operated at a rate of 2 tons per hour. Costs were estimated to be 149 (Canadian) per metric ton of soil treated. This estimate was based on the following assumptions the unit used medium naphtha as a solvent operations were 24 hours per day, for 260 days per year utilization factor of the facility was 83% capital costs were 2,548 million (Canadian) and capital amortized over 10 years at 10%, two payments per year. The estimate stipulated that the recovered oil was of suitable quality to be sold to offset process costs. It was estimated that the largest component of process costs would be labor ( 56 per ton of waste treated). Other cost components listed were capitalization costs ( 38 per ton), utilities ( 29 per ton), insurance ( 9 per ton), trucking and maintenance (each 5 per ton), equipment rental and site excavation and restoration (each 3 per ton), and waste disposal was estimated to cost 1 per ton (D17896F, p. 8). 

The entire remediation budget for the San lose solvent site was 948,000 for capital costs and 1,172,000 per year for operation and maintenance costs. The budget included remediation activities using several different technologies. The SIVE pilot test was estimated to cost 100/yd (D19966K, p. 3 D10330Q, p. 10). 

Originally, extractive distillation was limited to two-component problems. However, recent developments in solvent technology enabled applications of this hybrid separation in multicomponent systems as well. An example of such application is the BTX process of the GTC Technology Corp., shown in Figure 6, in which extractive distillation replaced the conventional liquid-liquid extraction to separate aromatics from catalytic reformate or pyrolysis gasoline. This led to a ca. 25% lower capital cost and a ca. 15% decrease in energy consumption (170). Some other examples of existing and potential applications of the extractive distillations are listed in Table 6. 

Capital costs for a Sulfinol unit are lower than alkanolamine units that have the same capacity. This is because the equipment is smaller as a result of less foaming and lower circulation rates. However, certain treating applications may not be ideal for the Sulfinol process. A reclaimer may be needed to remove DIPA degradation products when C02 partial pressure is high. Also, aromatic and hydrocarbon co-absorption occurs when solvent -to-gas ratios are high260-... 

Solvent recovery systems would also necessitate the specification of condenser duties, distillation tower sizes, holding tanks, piping, and valves. It is important to note that the engineering design of an adsorption system should be based on pilot data for the particular system. Information can usually be obtained directly from the adsorbent manufacturer. The overall size of the unit is determined primarily by economic considerations, balancing the operating costs against the capital costs. 

Purification can also be achieved in other ways, through precipitation with salts, crystallization, and through aqueous two-phase extraction. Some of these methods are associated with substantial capital cost, low throughput, low yields, or waste issues. Fractional precipitation, one of the oldest protein separation technologies, can be surprisingly effective to separate a compound of interest from a complex broth. For instance, the process of fractional solvent precipitation of blood plasma components has been used since World War II. 

Solvent extraction. Lab tests indicate that acetone extraction will produce the required product. Capital costs are estimated at 5.4M. Operating cost... 

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