Cost structures of lumber and coal drying processes together with an application of the factor method for prediction of the drying cost are presented.

Structure of Drying Costs

Once individual equipment costs are known from either manufacturers’ price quotations or estimating charts as discussed in the previous chapter, they can be utilized to form preliminary total plant cost estimates. A suggested sequence for obtaining such estimates is as follows: 

1.

Prepare a flow sheet for the process or operation to be estimated, showing all of the major equipment and whatever of the basic auxiliary or general plant facilities that directly affect the process (i.e., boilers for steam; cooling towers; special electric requirements, unusual storage facilities, transportation equipment, etc.).




2.

Prepare heat and material balances around each piece of equipment to the degree of accuracy and detail required to size the equipment.




3.

Size all of the equipment with the precision required to obtain the parameters needed for manufacturers’ cost quotations or to estimate costs from charts.




4.

Analyze the process carefully to determine what “plant cost factors” should be used, and then prepare a detailed breakdown of the total plant cost package. This will be discussed in the following sections.

Plant Cost Estimates

Life Cycle Costing Fundamentals

On presente graphiquement les couts de huits appareils (agitateurs, convoyeurs a vis, filtres, echangeurs de chaleur, pompes centrifuges, convoyeurs a bande, cuves), ce qui permet l'extrapolation

S. T. Slavsky

Papers

Updated cost factors: process equipment