Energy operating costs

At filling stations, the GH2 pressure is usually increased from 200 to 400 bar (3,000-4,500 psig). This compression increases the energy cost of the total operation by about 2% HHV. Naturally, in addition to the operating energy costs, there will also be infrastructure, depreciation, operating, and maintenance costs. 

Distillation columns should be optimized considering both capital cost and operating (energy) cost. The heuristics of using a reflux ratio of 1.03-1.3 times the minimum reflux ratio is in line with both the capital cost and the operating cost for binary distillation systems. 

In addition to the process benefits, there are cost and environmental benefits associated with the supercritical process. The supercritical fluid process has low operating energy costs when compared to other alternative solvent processes and the cost of the carbon dioxide used to supply the system is orders of magnitude less than the purchase costs of chlorofluorocarbons, especially with the added taxes imposed by the federal government. In addition, carbon dioxide is a more environmentally friendly material and does not have the disposal costs associated with other alternatives. 

The use ofoxygen instead of air might lead to improvements, such as a higher rate of oxidation and an increased productivity, the use of milder reaction conditions, a lower capital and operating energy costs, lower purge streams and a reduced cost for the treatment of vent gas. In fact, several companies already use O2 instead of air. Safety concerns are greater than with air operation, but the safety issues have been solved. 

When installing a piping system, both the best pipe and the best pump must usually be selected to deliver a prescribed flow. The term best in this case refers to that combination of pipe and pump that will minimize the total system cost, including both the capital cost of the pipe and pump stations as well as operating (energy) cost, i.e.. 

Relatively high operation energy costs, especially for high-efficiency systans that have large pressure drops. 

An NGL plant was selected to analyze several distillation assisted heat pump processes when compared to conventional distillation. The depropanizer column which is the third column of the NGL plant was suitable for retrofitting by heat pump systems. This conventional process, along with top vapour recompression, bottom flashing and absorption heat pumps, were simulated using the Aspen Plus software, in order to determine economically the best alternative. Distillation with both top vapor recompression and bottom flashing heat pumps allows reduction of operation (energy) costs by 83.3% and 84%, respectively. This improves the economic potential (incorporating capital costs) by 53% and 54%, respectively. 

It is obvious that temperature has an influence on catalytic oxidation efficiency however, in general the temperature required for complete oxidation of a VOC cannot be used independently as a controlling factor. This is because the reaction temperature varies according to the VOCs present, their concentrations, and the catalyst employed. The use of high temperatures wiU increase the efficiency of destruction of VOCs, but it can also accelerate catalyst deactivation, resulting in a reduction of activity. When applied industrially, relatively low temperatures are preferred so that operational energy costs can be minimised. 

Distillation capital costs. The classic optimization in distillation is to tradeoff capital cost of the column against energy cost for the distillation, as shown in Fig. 3.7. This wpuld be carried out with distillation columns operating on utilities and not integrated with the rest of the process. Typically, the optimal ratio of actual to minimum reflux ratio lies in the range 1.05 to 1.1. Practical considerations often prevent a ratio of less than 1.1 being used, as discussed in Chap. 3. 

Total annual fuel and energy costs Wages of engineers and operators A.nnual maintenance allowances... 

Food Processing. One of the first appHcations of RO was ia the food processiag (qv) iadustry. The primary advantage of RO over the traditionally used processes ia the food iadustry is that RO operates at low temperatures which can prevent the denaturation of some materials used ia foodstuffs. Because high temperatures are not required, energy costs are reduced as well. Moreover, RO is relatively simple ia terms of the equipment design. These factors lead ultimately to a reduction ia capital and operating costs, accompanied by an iacrease ia product quaUty. 

Because zinc-based alloys have low melting points, energy savings in the melting operation are substantial and the foundry operation is essentially free of fume. With the current trend of increasing energy costs and pollution control, cost benefits can be considerable (114). 

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