Proposal made to Petkim Petrokimya AS in April 1984

S F Bush

Summary

Outline proposals for mini polymer plants are advanced. This concept, which is being developed in the United Kingdom, is particularly suited to Turkey which has an expanding economy and consequent need for easy-to-build low cost plant which can be tied directly to processing.

The mini plant concept is advantageous for styrene-based plastics, particularly for Expanded Polystyrene and ABS compounding processes, at the 5,000-7,000 tons per annum scale. Sales of complete plant at this scale have recently been made to third countries.

Based on the likely costs, import duties and financial climate in Turkey, the returns on investment for these plants look extremely attractive.

Basic Concept

Polymer and chemical plant design has been dominated by the idea that the larger the unit, the lower the cost because labour, capital and overheads are spread over a larger production. This may still be true when all the product can be sold, when there are no breakdowns and when there are infrequent grade changes. Increasingly, because of technical and economic changes, these conditions are not met, and study has shown that much smaller plant (by a factor of 10 or more) linked to specific polymer products can give better and more certain returns on investment.

This arises because of a combination of economic and technical reasons as follows:

1. Direct sales of polymer to a specific polymer processing line cuts out polymer selling costs.
2. There are fewer and more foreseeable grade changes, thus reducing scrap rates at the polymer stage.
3. The polymer process can be tuned to the final product, thus increasing its quality and rducing scrap rates at this stage.
4. Because the physical size of plant is reduced, process control can often be more precise (this is especially true of polymer reactors).
5. Again because of plant size reduction, many more equipment items can be purchased off-the-shelf, thus gaining a direct cost advantage compared with much larger plant where some of the scale advantage is eroded by the requirement to have some items specially fabricated.