Solids processing costs

Processing Costs of Waste Materials in a Municipal Solid Waste Incinerator, Report TNO-MEP R96/248, TNO-MEP, Apeldoom, the Netherlands, 1996. 

For the factored estimate a list is made of all pieces of equipment, and the delivered cost of each item is obtained. This could be determined by inquiring from manufacturers, from past records, or from published data. The delivered cost of all the equipment is summed and multiplied by an appropriate factor. According to Lang this factor would be 3.10 for a solids process plant, 3.63 for a solid-fluid plant, and 4.74 for a fluid plant. These factors are referred to as Lang factors. This estimate is often used in the preliminary stages of engineering, but is not extremely accurate. 

The evaluation sited a number of factors that could affect process costs for groundwater treatment, including flow rate, type and concentration of contaminants, groundwater chemistry, physical site conditions, site location, availability of utilities, and treatment goals. Assumptions made for the cost estimate include any suspended solids are removed prior to CPFM treatment, the influent has an optimum pH of 8 to 9, and the ambient temperature of the influent is between 20 and 35°C. It was assumed that the system would be operational on an automated, continuous-flow mode, 7 days per week, 24 hours per day. This would lead to approximately 52.4 million gallons of water being treated in a 1-year period (D10957J, p. 22). 

The need to meet environmental regulations can affect processing costs. Undesirable air emissions may have to be eliminated and liquid effluents and solid residues treated and disposed of by incineration or/and landfilling. It is possible for biomass conversion processes that utilize waste feedstocks to combine waste disposal and treatment with energy and/or biofuel production so that credits can be taken for negative feedstock costs and tipping or receiving fees. 

The most common solvent is water. Water dissolves a great many gases, liquids, and solids, and is much used for this purpose. Other liquids similarly dissolve many substances without reacting chemically with them. Important considerations in connection wfith the choice of solvent for a given case are (1) vapor pressure and boiling point, (2) solvent power under stated conditions of temperature. (3) ease and completeness of recoverability by evaporation and condensation, and completeness of separation from dissolved material by evaporation. (4) heat of vaporization, (5) miscibility with water or other liquid, if present, (6) inertness to chemical reaction with the materials present, and with the apparatus, (7) inflammability and explosiveness. (8) odor and toxicity (9) cost of solvent, loss in process, cost of recovering. 

Another feature of these AOTs is that they are destructive types of water pollution removal processes because they eliminate compounds rather than transfer them to another medium. Thus, carbon adsorption or stripping transfers pollutants from one phase (water) to another phase such as a solid phase (carbon) or a gas phase (air). In the latter case, purification of air is required so that an additional step (i.e., carbon adsorption) is also needed, which implies higher processing costs. 

The purchased cost of equipment for a solid-processing plant is 500,000. The plant is to be constructed as an addition to an existing plant. Estimate the total capital investment and the tied-capital investment for the plant. What percentage and amount of the fixed-capital investment is due to wst for land and contractor s fee ... 

The reasons why incineration is viewed as an attractive recovery option are outlined and environmental challenges facing the incineration industry are considered. The overall European situation with regard to residue generation and processing costs is discussed and the progress being made towards the voluntary commitment of the PVC industry in relation to municipal solid waste incineration and other recovery processes. 15 refs. 

The three types of processes considered are a solids process - such as a process producing lime, a solid-fluid process - such as a powdered-coffee process, and a fluid process - such as a methanol-synthesis process. No sharp division exists among these process types so that you must use some judgment to classify a process. Table 2.6 contains average cost factors for these process types. The factors for process equipment depend on the material of constmction. Thus, Table 2.7... 

Dewatering is the removal of the vast majority of solids from a slurry to produce a cake that has body and integrity. The objective is to produce a conveyable/ truckable cake, increase the fuel value, or reduce the processing cost of the feed solids by removing the liquid, which is usually water. 

---