If calcined petroleum coke could command a premium, why not mattresses, bleach, sardines or processed meats?

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Petroleum coke is the solid black gunk left over at the end of the oil refining process.

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For the past 18 months engineers have been testing coal, petroleum coke (a refining by-product) and other fuels in the plant, tinkering with the catalyst and gathering data.

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But chemicals, coke, refined petroleum and nuclear fuel exports dropped 6.7% between January and March, with textiles, fur and leather down 5.7% and engineering and allied industries dropping by 2.8%.

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However, the textiles, fur and leather sector fell by 8.3%, and there was contraction in engineering and allied industries (-0.8%), chemicals, coke, refined petroleum products and nuclear fuel (-3.2%) and metals and metal products (-0.4%).

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