Costs recovered value

Fig. 28-2. Control equipment cost with value recovered.

The average net cost for this technology is 30 to 45 per ton of soil treated. As shown in the following table, the net cost per unit volume is reduced by subtracting the recovered value of the reusable product. The following table provides a comparison between asphalt-stabilized base/engineered backfill and other remediation options and disposal (D16903T, p. 4). 

In batch distillation, as the overhead composition varies during operation, a number of main-cuts and off-cuts are made at the end of various distillation tasks or periods (see Chapter 3). Purities of the main-cuts are usually determined by the market or downstream process requirements but the amounts recovered must be selected based on the economic trade off between longer distillation times (hence productivity), reflux ratio levels (hence energy costs), product values, etc. Increasing the recovery of a particular species in a particular cut may have strong effects on the recovery of other species in subsequent cuts or, in fact, on the ability to achieve at all the required purity specifications in subsequent cuts. The profitable operation of such processes therefore requires consideration of the whole (multiperiod) operation. 

An economic model has been provided by die American Plastics Council [6] of the current and potential commercial infrastmcture that recovers value from a portion of the ten million vehicles disposed of annually in the United States. The model provides for identification of transactions, costs, values and other factors that strongly affect decisions regarding plastics disposal, and could serve as the basis for modelling the recovery of plastics from a range of industries producing large arisings. 

The costs are presented per nitrogen assimilated. Values in parentheses are calculated on the synthesis and assimilation costs alone minus costs recovered from metabolism of PGA, but excluding the cost of the carbon skeleton. 

Bottom hole assemblies and certain types of downhole equipment (e.g. logging tools, MWD tools) cost several US 100,000. Some logging tools will have radioactive sources which may need to be recovered or isolated for safety and legal reasons. However, prior to commencing fishing operations, a cost - benefit assessment will have to be made to establish that the time and equipment attributable to the fishing job is justified by the value of the fish or the cost of sidetracking the hole. 

Mercury from these accumulated wastes is generally best recovered by total degradation in stills, where metallic mercury is condensed and collected. The recovery costs are amply compensated by the value of the metal recovered. Moreover, disposal problems are either eliminated or severely diminished. 

The throwaway fuel cycle does not recover the energy values present ia the irradiated fuel. Instead, all of the long-Hved actinides are routed to the final waste repository along with the fission products. Whether or not this is a desirable alternative is determined largely by the scope of the evaluation study. For instance, when only the value of the recovered yellow cake and SWU equivalents are considered, the world market values for these commodities do not fully cover the cost of reprocessing (2). However, when costs attributable to the disposal of large quantities of actinides are considered, the classical fuel cycle has been the choice of virtually all countries except the United States. 

Economic Analysis. The economic success of recycling programs is subject to the following inequaUty where X = the cost to recover recyclable materials, Y = the cost of disposal, and Z = the value of the resource recovered. 

When goods consigned to a shipper s warehouse or terminal are damaged, disputes frequentiy arise as to their value. Usually, the carrier contends that shippers should not earn profit on sales not made, and the shipper contends that it should not be required to produce goods merely to recover its costs. Such disputes are sometimes resolved by payment of the sales price less costs not incurred, such as the cost of deHvery from the warehouse to the consignee. 

Cost. The catalytically active component(s) in many supported catalysts are expensive metals. By using a catalyst in which the active component is but a very small fraction of the weight of the total catalyst, lower costs can be achieved. As an example, hydrogenation of an aromatic nucleus requires the use of rhenium, rhodium, or mthenium. This can be accomplished with as fittie as 0.5 wt % of the metal finely dispersed on alumina or activated carbon. Furthermore, it is almost always easier to recover the metal from a spent supported catalyst bed than to attempt to separate a finely divided metal from a liquid product stream. If recovery is efficient, the actual cost of the catalyst is the time value of the cost of the metal less processing expenses, assuming a nondeclining market value for the metal. Precious metals used in catalytic processes are often leased. 

Chemical MF is used in several apphcations to recover caustic values from cleaning or processing streams. An example is the caustic solution used to clean dairy evaporators, which may be cleaned for reuse by passing it through a microfilter. Significant savings in caustic purchase and disposal costs provide the incentive. Acids are also recovered and reused. Ceramic microfilters are most commonly used in these apphcations. 

The fuel value of most solid wastes is usually sufficient to enable self-supporting combustion, leaving only the incombustible residue and redlicing the volume of waste eventually consigned to sanitaiy landfills to only 10 to 15 percent of the original volume. The heat released by the combustion of waste can be recovered and utilized, although the cost of the recoveiy equipment or the distance to a suitable point of use for the heat may make its recoveiy economically infeasible. 

If the material recovered has some economic value, the picture is different. Figure 28-2 shows the previous cost of control with the value recovered curve superimposed on it. The plant manager looking at such a curve would want to be operating in the area to the left of the intersection of the two curves, whereas the local air pollution forces would insist on operation as far to the right of the graph as the best available control technology would allow. 

Now that you have determined the likely savings in terms of annual process and waste-treatment operating costs associated with each option, consider the necessary investment required to implement each option. Investment can be assessed by looking at the payback period for each option that is, the time taken for a project to recover its financial outlay. A more detailed investment analysis may involve an assessment of the internal rate of return (IRR) and net present value (NPV) of the investment based on discounted cash flows. An analysis of investment risk allows you to rank the options identified. 

This value corresponds to a corresponding y-scale composition of 0.0012, which is less than the supply mass fmction of phenol in either waste stream as well as the pinch composition. Hence, it is thermodynamically feasible for Sf to recover phenol from R] and R2. In addition, miy amount of phenol removed by S5 does not overlap with the load handled by the process MSAs. Therefore, the operating cost of air needed to remove 1 kg of phenol can be evaluated as follows ... 

In the previous problem, it is desired to compare the total annualized cost of the benzene-recovery system to the value of recovered benzene. The total annualized cost TAC for the network is defined as ... 

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