Cost estimation battery limits

ISBL, inside battery limits OSBL, estimated erected cost. outside battery limits EEC,... 

The battery limits investment may be estimated by applying installation factors to the cost of individual items of equipment ... 

As an example, the battery-limits capital cost can be estimated for the production of 10,000 t/yr of ethylene (qv) from ethanol (11). Seven processing blocks, ie, vaporizer, reactor, water quench, compressor, dryer, distillation, and energy recovery, can be identified. The highest temperature is 350°C (reactor), and the highest pressure is about 1.7 MPa (17 atm) (compressor, two towers). If a materials-pressure factor, + of 1.03 is assumed, then for N = 7 0 = 0.87 1/0 = 1 64 and f =0 K = 6.3. This gives the 1981 cost as 4.4 X 10 . The 1991 battery-Hmits investment can be obtained, by updating with the CE Plant Cost Index, as 5.3 x 10 . ... 

Base equipment includes all equipment within the battery limits whose cost is as significant as the cost of a pump. For example, storage tanks, knockout drums, accumulators, heat exchangers, and pumps are classed as main-plant items (MPl). Early in the development of the process-flow diagram, it is advisable to increase the estimated (MPl) cost by 10 to 20 percent to allow for later additions. When the scope of the process has been well defined, (MPl) costs should be increased by 1 to 10 percent. 

Early in the life of a project, information has not been developed to allow definitive cost estimates based on material takeoff and vendor quotes for equipment. Therefore, it is necessary to estimate the cost of a facility using shortcut methods. The first step is to develop or check flow-sheets, major equipment sizes, and specification sheets as described in earlier chapters. From the equipment specification sheets, the cost of each piece of equipment is estimated, using techniques discussed later. Once the major equipment cost has been estimated, the total battery limit plant cost can he quickly estimated using factors developed on a similar project. 

Total Offsite Costs. The offsite costs can range from 20% to 50% of the total cost of the project. If a preliminary built-up estimate of the offsites is less than 30% of the total costs, it should be suspect. Unless the offsites are very well defined, it would be better to use a factor of 50% to 75% of battery limits estimate as the offsite figure. 

An alternative to a factored estimate, in some cases, can be a scaled estimate if the battery limits cost of a similar plant is known, but the size is different. The cost of the new plant, C , is equal to the known plant cost, C, times the ratio of the two plants capacity raised to a fractional power. That is ... 

Solve the problem given in Example 9-4 using the Miller method. Let us assume that 10 of the pumps and all the storage tanks are not within the battery limits. The total estimated F.O.B. price of the equipment in 1972 is then 1,105,000. The cost of it delivered, assuming a 5% freight charge (sales tax is not included), is... 

This is a multiplier , which when applied to the purchase prices of major pieces of chemical process equipment, provides an estimate of the installed cost of the chemical process. b ISBL, inside battery limit. c OSBL, outside battery limit. 

Classification of Estimates There are two broad classes of estimates grass roots and battery limits. Grass-roots estimates include the entire facility, starting with site preparation, buildings and structures, processing equipment, utilities, services, storage facilities, raihoad yards, docks, and plant roads. A battery-limits estimate is one in which an imaginary boundary is drawn around the proposed facihty to be estimated. It is assumed that all materials, utilities, and services are available in the quality and quantity required to manufacture a product. Only costs within the boundary are estimated. 

Estimate by the turnover-ratio method the fixed-capital investment required for a proposed sulfuric acid plant (battery limit) which has a capacity of 140,000 tons of 100 percent sulfuric acid per year (contact-catalytic process) using the data from Table 19 for 1990 with sulfuric acid cost at 72 per ton. The plant may be considered as operating full time. Repeat using the cost-capacity-exponent method with data from Table 19. 

Estimated inside battery limits (ISBL) costs based on unit processing 158,000 mtpy of BT reformate feedstock with 68 LV% aromatics (US Gulf Coast site in 2003). 

Economics The solvent used in the Sulfolane process exhibits higher selectivity and capacity for aromatics than any other commercial solvent. Using the Sulfalane process minimizes concern about trace nitrogen contamination that occurs with nitrogen-based solvents. Estimated inside battery limits (ISBL) costs based on a unit processing 158,000 mtpy of BT reformate feedstock with 68 LV% aromatics (US Gulf Coast site in 2003). 

Economics Estimated inside battery limits (ISBL) erected and utility costs are given for a Parex-lsomar complex which includes the xylene splitter column and the o-xylene column, US Gulf Coast fourth quarter 2002. 

Typical methods are those of F. C. Zevnik and R. L. Buchanan [Chem. Eng. Progr., 59, 70-77 (Feb. 1963)] and J. H. Taylor Eng. 6-Proc. Econ., 2, 259-267, 1977). The former is mainly a graphical method of estimating the cost per functional unit Cp) based on the capacity, the maximum pressure, the maximum temperature, and the materials of construction. The Taylor method requires the determination of the costliness index, which is dependent on the complexity of the process. A simpler method was suggested by S. R. Timms (M.Phil. thesis, Aston University, England, 1980) to give the battery limits cost for gas phase processes only in U.S. dollars with a Marshall and Swift index of 1000. The simple equation is... 

Multiple-factor methods include the cost contributions for each given activity, which can be added together to give an overall factor. This factor can be used to multiply the total cost of dehvered equipment Z (Ceq)del to produce an estimate of the total fixed-capital investment either for grass-roots or for battery-limit plants. The costs may be divided into four groups ... 

For control purposes it is advisable to estimate startup cost and time beforehand and then try to stay within the estimates. The general parameters which can be used to estimate startup cost Cso, which are usually between 2 and 20 percent of the battery-limit fixed-capital cost, are as follows ... 

Based on the preliminary process design, battery limits capit2d and operating costs were estimated for mid-1988. Hie battery limits plant conprises equipment and systems directly associated with the supercritical extraction operation, as shown in the process flowsheet (Figure 1) Offsites, such as materied shipping and handling, buildings, land, etc., were not included. 

A battery limits cspital investment of 2.8 millicxi was estimated for the base case, and 6.2 million for the hi capacity design. A battery limits production cost for an average ioe of l.l/kg ( 0.50/lb) was estimated, based on raw material, for the base case plant. Production co declines significantly as plant size increases, reaching 0.5/kg ( 0.24/lb) for the hi capacity case. 

Catalytic distillation essentially eliminates catalyst fouling because the fractionation removes heavy coke precursors from the catalyst zone before coke can form and foul the catalyst bed. The estimated ISBL (inside battery limits) capital cost for 35,000bpd CDHydro/CDHDS unit with 92% desulfurization is US 25 million, and the direct operating cost including utilities, catalyst, hydrogen, and octane replace-... 

On the basis of the price levels as of spring 1979 and at the translation rate of 200 yen to one dollar, the construction cost of the Dry Process PUROX System in Japan is estimated to be about 13,000,000 for a 200 Mg/d facility ( 65,000 for Mg of refuse), exclusive of the land, utility supply facilities down to the battery limits, and fixtures and supplies. This is about 10% higher than the construction cost in Japan of the stoker incinerator, which is estimated to be about 58,500 per Mg of refuse. 

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