Waste capital cost

The capital cost of most aqueous waste treatment operations is proportional to the total flow of wastewater, and the operating cost increases with decreasing concentration for a given mass of contaminant to be removed. Thus, if two streams require different treatment operations, it makes no sense to mix them and treat both streams in both treatment operations. This will increase both capital and operating costs. Rather, the streams should be segregated and treated separately in a distributed effluent treatment system. Indeed, effective primary treatment might mean that some streams do not need biological treatment at all. 

Particle Segregation Mechanisms. Segregation is the process by which an assembly of soHd particles separates as it is being handled. This often results in cosdy quaUty control problems due to the waste of raw or finished materials, lost production, increased maintenance, and capital costs required to retrofit existing faciUties. 

The unit cost approach is widely used for quick estimates of the capital cost of utiUties, waste treatment faciUties, and buildings, where data in /kW, /t of waste, /m, etc, are available. 

ACC Annualized capital costs MSW Municipal solid waste... 

Pollutants that require an unusually high level of control or that require the fabric filter bags or the unit itself to be constructed of special materials, such as Gore-Tex or stainless steel, will increase the costs of the system. The additional costs for controlling more complex waste streams are not reflected in the estimates given below. For these types of systems, the capital cost could increase by as much as 75 % and the operational and maintenance (O M cost could increase by as much as 20%. 

It is most economical when high-grade ores are used, becoming less economical with poorer feed materials containing iron, because of the production of chloride wastes from which the chlorine cannot be recovered. By contrast the sulfate process cannot make use of rutile which does not dissolve in sulfuric acid, but is able to operate on lower grade ores. However, the capital cost of plant for the sulfate process is higher, and disposal of waste has proved environmentally more difficult, so that most new plant is designed for the chloride process. 

Thermal power plant is more commonly associated with very large central power stations. The capital cost for thermal power plant, in terms of cost per installed kilowatt of electrical generating capacity, rises sharply for outputs of less than some 15 MW. It is for this reason that thermal power plant is not usually considered for industrial applications unless it is the combined cycle or combined heat and power modes. However, for cases where the fuel is of very low cost (for example, a waste product from a process such as wood waste), then the thermal power plant, depending on output, can offer an excellent choice, as its higher initial capital cost can be offset against lower running costs. This section introduces the thermal power cycle for electrical generation only. 

Production costs include capital-dependent costs, e.g. depreciation, interest, insurance, and taxes and operating costs such as costs of raw materials and auxiliaries, costs of utilities, waste-disposal costs, labour costs, maintenance costs, and overheads. 

Figure 3.1 Recovery of heat from a waste steam involves a trade-off between reduced energy cost and increased capital cost of heat exchanger.

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