Total Production Cost

The total annual production cost equals the sum of the cost of manufacture and general expenses. 

Continuous plant operation Feedstock MCB product Benzene co-product HCl gas co-pioduct Total bare-module costs, Cxbm Cost of site preparation and service facilities, 

Allocated costs for utilities and related facilities, Cauoc Cost of contingencies 18% of Cdpi 

The total depreciable capital, using Table 16.9, is computed as follows  

For this moderate-size plant, with one section, use 2 operators/shift. Using Table 17.1 with the above data, the following annual costs are computed 

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Secunda discharges no process water effluents. AU. water streams produced are cleaned and reused in the plant. The methane and light hydrocarbons in the product are reformed with steam to generate synthesis gas for recycle (14). Even at this large scale, the cost of producing fuels and chemicals by the Fischer-Tropsch process is dominated by the cost of synthesis gas production. Sasol has estimated that gas production accounts for 58% of total production costs (39). 

As can be seen from this analysis, the natural gas feedstock and capital charges amount to over 93% of the total production cost before return on investment. Therefore, energy consumption and capital investment are the key factors in determining ammonia production profitabiUty. 

An estimate of total product cost is an important part of economic evaluation and management planning. Total product cost can be viewed as the sum of the manufacturing cost and the general expense. 

General expense can be approximated as 15—20% of the total product cost. Typical category factors, as percentage of total product cost, are 3% for administration, 10% for sales, and 4% for research and development (R D) (1). 

The modern trend is for overhead costs to become an increasing proportion of total product costs. This results from the ever-greater sophistication of process plants. Therefore, it is highly desirable that chemical engineers should have some say in the location of overheads and that this should not be left entirely to accountants. 

Maintenance costs are a major part of the total operating costs of all manufacturing or production plants. Depending on the specific industry, maintenance costs can represent between 15 and 40 per cent of the costs of goods produced. For example in food related industries, the average maintenance cost represents about 15 per cent of the cost of goods produced while in iron and steel, pulp and paper and other heavy industries maintenance represents up to 40 per cent of the total production costs. 

The tables that follow give the costs of various SCP production processes in comparative rather than in actual form. To see what this means examine Table 4.9. The production cost of raw materials for yeasts grown on n-alkanes is given as 58.5. This means that tire cost of raw materials accounts for 58.5% of the total production costs of this process. The same cost for bacteria grown on methanol is 73.8. This means that in this case 73.8% of the total production cost is accounted for by raw materials. This does not mean that the actual cost of raw materials for tire methanol process is more titan that for the n-alkanes process, as the total costs of the two processes are not necessarily similar. 

The total production costs will be increased with sales and administration plus research and development, so the final production costs will be 13.04 kg 1 + ( 2.6 to 350) giving a total production cost at 100% capacity of 15.64 to 1654 per kg of phenylalanine. 

The substrate contributes least to production cost when it is a waste. See Table 4.9 -Sulphite waste liquor is the waste and contributes only 17% to total production cost... 

Aeration comprises 88.9% of the running costs of fermentation (Table 4.12). Running costs of fermentation comprise 67.9% of the Total running costs (Table 4.11). Running costs comprise 23.8% of the total production cost (Table 4.9). 

Ammonia comprises 11.1% of total production costs (Table 4.9). Ammonia thus contributes 0.42 x 11.1/100 = 0,046 per kg biomass. 

Example 2 activity, yield, and total production cost of proteins from fermentation units... 

As a rough estimate the cost can be taken as 20 to 30 per cent of the operating labour cost, or 2 to 4 per cent of the total production cost. 

Some optimization techniques minimize the cost of product of a system or a component. The optimum total production cost rate with respect to NTU is obtained from... 

When the specified production capacities are low, processes based on batch reactors will usually have lower capital investment requirements than processes calling for continuous operation, so batch reactors are often preferred for new and untried processes during the initial stages of development. As production requirements increase in response to market demands, it may become more economic to shift to continuous processing but, even in these cases, there are many industrial situations where batch operation is preferable. This is particularly true when the operating expenses associated with the reactor are a minor fraction of total product cost. At low production capacities, construction and instrumentation requirements for batch reactors are usually cheaper than for continuous process equipment. Moreover, it is generally easier to start up, shut down, and control a batch reactor than a comparable capacity continuous flow reactor. 

Several factors contribute to the total production costs of household appliances ... 

Minimize total production costs per average production costs with respect to time per fraction conversion. 

Location Hydrogen production Feedstock cost (electricity cost) (Ct/kWhH2) (ct/kWhJ Plant-related costs (Ct/kWhH2) Total production costs (ct/kWhH2)... 

Obviously, a single collection area of 25 km radius could only feed a plant of half the size assumed here. Since plant costs scale with the plant capacity raised to the power 0.65-0.8, such a two-fold smaller plant would have a 20-25% higher capital charge (per ton of product). This would result in additional processing cost and total production cost of 1-2 GJ 1 for biocrude plant, 2-5 GJ-1 for a biofuel plant and 5-6 GJ-1 for a power plant. 

In Phases 2 and 3, it is not only the results of the catalyst tests (selectivity, activity, productivity, catalyst costs, etc.) but also the total product costs that decide whether the catalytic route will be further developed, or abandoned. 

For more expensive enzymes the continuous use of enzymes made possible by their iimnobihsation can result in considerable savings. By comparison typical chemical catalysts represent a smaller proportion of the total manufacturing costs. Thus the catalysts used in ammonia, cyclohexane and styrene manufacture have been estimated to cost approximately only 0.7, 0.6 and 0.6% of the total production costs respectively. Thus biocatalysts are still in general comparatively expensive compared with chemical catalysts. 

Power Consumption Power consumption sometimes becomes important in industrial bioprocesses, because the power used for aeration and agitation can be highly expensive. The cost of power consumption occupies approximately 15-20% of total production cost in aerobic fermentation processes. 

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