Economics of Olefin Production from Coal and Gas

The route via methanol is analysed. The economics of olefin production for coal and gas is considered in two parts, first the production cost of methanol and then the conversion of methanol into 

For methanol, three scenarios are considered two large scale gas plants and one from coal. The estimate is made for the production of AA grade which is not usually necessary for the conversion to olefins. This may save a modest amount (5%) of the capital cost. The statistics are given in Table 11.5. 

A typical long-term average traded price for methanol is in the vicinity of 150/tonne. For this, gas prices have to be below 2/GJ and preferably in the vicinity of 1/GJ. At this time, a typical traded price of gas is in the range of 5/GJ and this has stressed many operations which are force to pay this price. For this reason new gas-based world scale methanol plants have migrated to regions of low gas prices in the Middle East. 

Coal based plants have a higher relative capital cost and the fixed variable curve is at a higher level than for gas based operations. However, coal is widely available at 0.5/GJ (c. 10/t) or less which reduces the production cost to below 200/t. 

This analysis is sensitive to the prevailing price of crude oil and by-products (butenes and naphtha) which change in relation to the oil price. With oil at 70/bbl, which is used as the basis for the sensitivity, the by-products, butenes and naphtha, are valued at 600/t. The fixed 

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