If coal is heated in the absence of air, coal tar is produced.在隔绝空气的状态下加热煤, 便会产生煤焦油。

Between June 2002 and February 2003, Australian Waste Recyclers received more than 200 separate loads of coal tar waste.在2002年6月至2003年2月期间, 澳大利亚废物回收公司回收了200多车煤焦油废料。