Plant Design and Cost

CONCEPTUAL DESIGN PRELIMINARY DESIGN DETAILED DESIGN CONSTRUCTION START-UP FULL OPERATION 

The second phase is normally called preliminary engineering and its objective is normally two fold sufficient engineering to achieve overall definition of scope for the project and establish a firm budget for completion of the project. The estimate prepared at this point is normally called the authorization estimate. With this information, the decision is made on whether the project is to be completed. To get to this point usually takes between 15 and 3 0% of the total design cost. Some will call this the definition phase of the project. 

Overstaffing can lead to methods of operation that are expeditious, but not sustainable for the plant to be profitable. The plant staff is best supported by staff that plans to leave the project. When the plant proves itself capable of full operation by unaugmented staff, it can be declared out of start-up and dedicated to plant operations. 

These are the phases that a capital project passes through from inception to dedication. Overlapping of the phases and compression of schedule is commonly achieved through an approach called fast tracking. It 

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In the meanwhile, the precautionary assumption continues to be used by regulators that there is a linear relationship between the level of radioactivity and the risk of cancer even at very low levels. That has a considerable effect on plant design and costs, but it is difficult to see how this could be changed whilst there is such disagreement within the scientific community". 

The AHj. does however have an important bearing on plant design and costs. An endothermic reaction requires energy to drive it, which is an additional cost. The energy has to be supplied efficiently to the reaction section of the plant, which has a significant impact on reactor design and cost. 

Tentative commercial plant design and cost estimates Research development Manufacturing sales patent division (final patent review)... 

A preliminary plant design and cost analysis for the particle board processing was performed 20). This projection used extensive distillation... 

Throckmorton, P.E., Pryde, E.H., 1972. Pilot run, plant design and cost-analysis for reductive ozon-olysis of methyl soyate. JAOCS 49, 643-648. 

Eor this example the cost of the battery limits plant is about four times the purchase cost of the equipment. This number is about two for module I-type plants designed and iastalled by the fine chemicals company itself, and about six for expanded module IV-type plants designed and built by contractors. 

The choice of a specific CO2 removal system depends on the overall ammonia plant design and process integration. Important considerations include CO2 sHp required, CO2 partial pressure in the synthesis gas, presence or lack of sulfur, process energy demands, investment cost, availabiUty of solvent, and CO2 recovery requirements. Carbon dioxide is normally recovered for use in the manufacture of urea, in the carbonated beverage industry, or for enhanced oil recovery by miscible flooding. 

FIG. 14-79 Cost of trays in plate towers. Price includes tray deck, bubble caps, risers, downcomers, and structural-steel parts. The stainless steel designated is type 410 Peters and Timmerhaus, Plant Design and Economics for Cbemical Engineers, 4th ed., McGraw-Hill, New York, 1.9.91). 

FIG. 14-81 Fabricated costs and installation time of towers. Costs are for shell with two beads and sldrt, but without trays, packing, or connections. (Peters and Timmerhatis, Plant Design and Economics for Chemical Engineers, 4th ed., McGraw-Hill, New Yoik, 1991. )... 

All DAFs are similar to each other in terms of theory, principles, design, operation, and secondary flotation performance. The authors select the circular DAF process equipment manufactured by KEC for the purpose of feasibility studies. The users should contact more than one major DAF and DAFF manufacturers for appropriate pilot plant demonstrations and cost comparisons. Rectangular DAF and DAFF clarifiers are as good as circular DAF and DAFF clarifiers. 

This book applies a systems philosophy to the preliminary process design and cost estimation of a plant. In doing so, it tries to keep in perspective all aspects of the design. There is always a tendency on the part of designers to get involved in specific details, and forget that their job is to produce a product of the desired quality and quantity, at the lowest price, in a safe facility. What is not needed is a technological masterpiece that is difficult to operate or costly to build. 

Other multiple-factor methods that have been published in the past are those by C. E. Chilton, Cost Estimation in the Process Industries, McGraw-Hill, New York, I960 M. S. Peters, K. D. Timmerhaus, and R. E. West, Plant Design and Economics for Chemical Engineers, 5th ed., McGraw-Hill, New York, 2003 C. A. Miller, Chemical Engineering, Sept. 13,1965, pp. 226-236 and P. A. Holland, P. A. Watson, and V. K. Wilkinson, Chem. Eng., Apr. 1,1974, pp. 71-76. These methods produced preliminary quality estimates. Most companies have developed their own in-house multiple-factor methods for preliminary cost estimation. 

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