Plant costs correlating

Water Systems These systems usually form the third highest cost item in chemical-plant anxiharies, with cooling towers representing the largest part of the investment. Although the installed cost increases with the terminal temperature range, an approximate cost correlation is given by... 

The cost of the biofuel plants reported in the literature appeared to follow the same general laws as those of chemical and fuels plants [77, 78] irrespective of the technology applied, the plant cost showed a nice power-law correlation (R2 of 0.88) with the overall energy loss of the plant over two orders of magnitude. It correlated much less (R2 of 0.56) with capacity of the plant. 

All eleven references in this category relate directly to Section 6.1, the Economic Evaluation of this project. They contain capital costing methods, cost correlations, typical plant and equipment costs, and economic indicators to account for cost changes with time. 

Cost Estimates - Plant investment costs were developed using cost correlations based on actual plants constructed by Standard Oil Company of California. The important bases for these estimates are summarized in Table XVIII. Costs for the overall Case 1 refinery are broken down and detailed in Table XIX. Investments are categorized as "onplot," those directly concerned with the individual refinery process plants, and "offplot," for auxiliary or supporting facilities, such as utility plants, tankage, etc. The estimating allowances shown... 

Cost correlations based on actual plants constructed by Standard Oil Company of California from the 1960 s through mid-1970 s. In addition to adjustments for inflation, size and known differences in plant location, the base estimates include allowances for ... 

An alternative approach is Bridgewater s method, which correlates plant cost against number of processing steps (Bridgewater and Mumford, 1979). For plants primarily processing liquids and solids ... 

As an example of correlating plant costs, the cost data from a nylon intermediate plant constructed from stainless steel was accumulated and converted to factors as shown in Table 2. 

In a similar fashion, cost correlations for large wood-fired plants were developed from correlations available in the literature ( ) for installation cost, and operation and maintenance cost for coal plants. The costs for a wood-fired power plant were found to be 20 percent higher than those for a coal-fired plant of the same size. On this basis, cost equations for large wood-fired power plants are as follows (in 1976 dollars) ... 

The utility cost coefficients A and B are characteristic of the considered utility and can be given either by a single number, as in the case of purchased electricity (A = 0.00013 and B = 0.01), or by a correlation, as in the case of compressed air (A = 0.00005 In p and B = 0.0009 In p, where q and p are the total air-plant capacity and the delivered air pressure, respectively). Tabulated data on the utility cost coefficients are given by Ulrich [34,35]. The CE Index in Equation 65.6 is the Plant Cost Index reported monthly in Chemical Engineering. 

In order to calculate the CO2 avoidance costs, the capital investment costs are first calculated using a conceptual cost estimation method with an accuracy of 40%. In this method, the main equipment costs are estimated. The costs for blowers, the heat exchanger and the columns have been calculated using correlations reported by Seider et al. [24] and Loh and Lyons [25] and are updated to costs in 2010 using the Chemical Engineering Plant Cost Index (CEPCI). 

Many auxiliary/support facilities are complex units in their own way, they can be as complex as the primary production units they support. An estimate sfart-ing with item by item equipment design could be as time consuming as the primary plant estimate itself. Fortunately, with available cost correlations, the job of estimating costs associated with steam generating plants,... 

It can be shown that the plant costs for a variety of processes correlate with the energy transfer (heat transfer, compression) within die process scheme [289]. As an example, the energy consumption of ammonia production has decreased over the last 50 years from about 40 GJ/t to 29 GJ/t corresponding to a thermal efficiency (LHV) of 65% or 73% of the theoretical minimum [169] [420]. 

We present the simulation of a combined heat and power plant. There are different commercial tools that can perform the simulation (or the synthesis) very efficiently (e.g.. Aspen Utility PlannerT> or Ariane by ProSim ) using databases and cost correlations obtained directly from industrial applications. The objective here is to show that it is possible to simulate a complex system taking advantage of some of the particularities of Aspen HYSYS. 

SuperPro Designer estimates equipment cost using built-in cost correlations that are based on data derived from a number of vendors and literature sources. In addition, users have the flexibility to enter their own data and correlations for equipment cost estimation. The fixed capital investment is estimated based on equipment cost using various multipliers, some of which are equipment specific (e.g., installation cost) while others are plant specific (e.g., cost of piping, buildings, etc.). This approach is described in detail in the literatrue [6,142]. The rest of this section provides a summary of the cost analysis results for this example process. Table 15.2 shows the key economic evaluation results for this project. Key assumptions for the economic evaluations include 1) a new production suite will be built and dedicated to the manufacturing of this product 2) the entire direct fixed capital is depreciated linearly over a period of twelve years 3) the project lifetime is 15 years, and 4) 27,000 kg of final product is produced per year. 

Several rules of thumb have been developed for estimating operating costs. For instance, Grumer (Reference 3) suggests that the raw material costs can be estimated as a percentage of the sales price of the finished product. Correlations have been made that indicate the overall operating costs can be related to the lbs of products, i.e., the total operating costs are a constant cents/lb of finished product. This obviously will work only when history can be used to get the recent cost on a similar plant. 

The most difficult feature of this method is that for each type of plant or plant product as well as for each type of equipment there is a break-point where the 0.6 no longer correlates the change in capacity. For small equipment or plants in reasonable pilot or semi-works size, the slope of the cost curve increases and the cost ratio is greater than 0.6, sometimes 0.75, 0.8 or 0.9. From several cost values for respective capacities a log-log plot of capacity versus cost will indicate the proper exponent by the slope of the resultant curve. Extrapolation beyond eight or ten fold is usually not too accurate. 

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