Screens capital cost

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. 

Furthermore, it is possible today to enter the field of combinatorial chemistry relatively easily, and achieve the immense economies of scale shown in Table 24.1. For example, it is possible to buy ready-made combinatorial libraries built around specific molecular themes and consisting of many thousands of compounds, and it is also possible to create a high-throughput screening system for that library using automated, off-the-shelf instrumentation. This may enable one to be using combinatorial chemistry very quickly, and is one of the key characteristics of the field today it can be considered a commodity, available to anyone for a modest capital cost. 

GenSim s structure makes sensitivity analysis easy. A representative screen (solar PV) is shown in Figure A3. This screen allows the user to compare LCOE costs at either comparable capacity factors (i.e., all at 50%), or at default or user defined capacity factors (i.e., solar PV at 20% with nuclear at 90%). LCOE estimates are displayed at the top of the graph. These estimates change as the user changes key assumptions using either the sliders or number boxes on the bottom half of the screen. For example, changing the assumed capital costs for solar PV from 3868 to 1500 /kW reduces the LCOE from 26.0 to 10.4 cents/kWh. 

This system has many advantages over the screening method used in the USA (Newman and Hannan, 1978). The sereening process is really only suitable for the separation of meat bones. Meat separation is more efficient using pressure methods, and very little heat is generated. It is not necessary to crush the bones prior to separation. The machines themselves are also easier to use and clean. One drawback is the extra capital costs associated with pressure machines. Economically there are only certain types of bones that are suitable for the production of MSM. Generally, the bones around the ribs and sternum are used, as these contain most meat. Some separation machines use whole bones others exploit ground bones. 

Three HiGee units were installed by Dow Chemicals in the US for stripping hypochlorous acid, used as the reactive chemical in a process. The rotating packed-bed used for stripping was selected after other alternatives such as a spray distillation tower were rejected for capital cost reasons. The packing selected was a woven wire screen, with the gas flowing counter-current to the liquid. Various packing surface areas were tested, with 2000-3000 m /m area densities, but these exhibited no performance differences so the lower value was used. 

All the techniques that have been discussed in this chapter use the fixed capital cost and the operating costs in order to evaluate the profitability of a process. Clearly, the accuracy of such predictions will depend on the accuracy of the estimates for the different costs. When screening alternative processes, it is sometimes useful to evaluate the difference between the revenue from the sale of products and the cost of raw materials. This difference is called the profit margin or sometimes just the margin. 

Some options (such as procedural changes) may involve limited capital costs and may be implemented in a short time frame. The screening step should consider the ease of implementation. If such an option is clearly desirable and indicates a potential cost saving, it should be considered for further study. 

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