Process cost

Cosmetics industry Cosmic radiation Cosmid vectors Cosmocil CQ CoS04 7H20 Cosorb process Cost estimates... 

Table 5. Estimated U.S. Processing Costs of Waste Disposal Method ...

Polymer recycling process costs for various operations are summarized in Table 6. 

Process costs for the methanolysis and glycolysis of PET to produce monomers are similar. Cost estimates are summarized in Table 8. 

M-type ferrites are mainly used as permanent magnet material. They have largely replaced the alnicos as preferred permanent magnet material, as a result of the lower material and processing costs. These ferrites were first introduced under the trade name Ferroxdure, the isotropic form in 1952 (22) and the anisotropic (crystal oriented) form in 1954 (23), and are widely available commercially under various trade names such as Oxid and Koerox. They cover about 55% of the world market of permanent magnet materials, corresponding to 1100 million U.S. doUars (1991), as weU as 55% of the U.S. market, at 300 million. 

Solvent extraction removes chlorophyll and other pigments to give a light-colored product but increases processing costs. Furthermore, solvent extraction removes p-carotene and reduces vitamin A activity (89) (see Terpenoids Vitamins). Supercritical CO2 extraction at 30 and 70 MPa (4,350 and 10,150 psi) and 40°C removed 90 and 70% carotene and lutein, respectively, from alfalfa LPC (96). This process avoids organic solvent residues and recovers valuable by-products. 

The need to meet environmental regulations can affect processing costs. Undesirable air emissions may have to be eliminated and Hquid effluents and soHd 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. 

Process Costs, Wulff Acetylene," Chem. Process. Eng. 47(2), 71 (1966). 

Some of the economic hurdles and process cost centers of this conventional carbohydrate fermentation process, schematically shown in Eigure 1, are in the complex separation steps which are needed to recover and purify the product from the cmde fermentation broths. Eurthermore, approximately a ton of gypsum, CaSO, by-product is produced and needs to be disposed of for every ton of lactic acid produced by the conventional fermentation and recovery process (30). These factors have made large-scale production by this conventional route economically and ecologically unattractive. 

Processing costs include those for size reduction, size classification, minerals concentration and separations, soHd—Hquid separation (dewatering), materials handling and transportation, and tailings disposal. Size reduction, one of the most expensive unit operations in minerals processing, could account for as much as 50% of the total energy consumed. This cost varies considerably from deposit to deposit and quite often from one area of a deposit to another. Ore bodies are extremely heterogeneous and the associated minerals Hberation, complex. 

Separation Processes. Separation of the catalyst from the products is a significant expense the process flow diagram and the processing cost are often dominated by the separations. Many soluble catalysts are expensive, eg, rhodium complexes, and must be recovered and recycled with high efficiency. The most common separation devices are distiUation columns extraction is also appHed. 

In 1976, over 3,000,000 tons of soda ash were produced in the United States using the Solvay process. This process has been discontinued in the United States because of pollution problems and high processing costs. It is stUl an important process in other countries. 

Economic Aspects. Several pubUcations probe the various areas of electroorganic process cost. CeUs (90), overaU process costs (41,91—93), economic optimization (94,95), and a comparison between the chemical and electrochemical methods (91,96) are aU discussed. 

Sensitivity Analysis An economic study should pinpoint the areas most susceptible to change. It is easier to predict expenses than either sales or profits. Fairly accurate estimates of capital costs and processing costs can be made. However, for the most part, errors in these estimates have a correspondingly smaller effecl than changes in sales price, sales volume, and the costs of raw materials and distribution. 

In practice there are two major classifications of cost accounting systems, job costing and process costing. In the former, costs are col-lec ted for each job or batch irrespective of the accounting period. This system is normally used in construction work. Process costing is normally used in continuous and semicontinuous processes. Costs are collected for a specific accounting period. 

Let us consider the manufac ture of metal ornaments. The processing cost, exclusive of material, may vaiy veiy httle for a wide range of materials. However, the direct materials cost will be much greater for precious than for base metals. In this case, an overhead allocation on the basis of direct material costs could be veiy misleading, while one based on direct labor cost could be quite accurate. 

The mamifac turing cost of a product is the sum of the processing or conversion cost and the cost of raw materials. The processing cost can be roughly broken down into three parts investment-related cost, labor-related cost, and utility cost. 

Let us consider a plant of fixed-capital cost Cfc- If the annual property taxes are taken as 0.02 Cfc, insurance as 0.01 Cfc, and maintenance as 0.06 Cfc, the annual investment-related cost woiild be 0.09 Cfc- Annual utilities cost is A. The annual processing cost Ap can be represented by... 

The annual processing cost Apo for a similar plant of a different size designed for an annual produc tion rate Ro can be approximately calculated from an equation of the form... 

The processing cost per unit of production for a plant with an annual production Ro can be approximately calculated from... 

Equation (9-208) can be used to compute data for plots such as Fig. 9-40, which shows the decrease in processing cost per unit of production ApoIRo with increasing plant size. 

FIG. 9-40 Decrease in processing cost against increase in plant size. 

They are, potentially or actually, cheap. Most ceramics are compounds of oxygen, carbon or nitrogen with metals like aluminium or silicon all five are among the most plentiful and widespread elements in the Earth s crust. The processing costs may be high, but the ingredients are almost as cheap as dirt dirt, after all, is a ceramic. 

It is obvious that the range of possible formulations based on poly(vinyl chloride) and related copolymers is very wide indeed. For each end-use the requirements must be carefully considered and a formulation devised that will give a compound of adequate properties at the lowest cost. In assessing cost it is not only important to consider the cost of the compound but also comparative processing costs, the possible cost of storing additional materials and many other cost factors. 

---