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The method involves a piece of copper covered with light sensitive bitumen .

该方法用到一片铜片，上面用光敏感的沥青覆盖。

Companies extract bitumen from a mix of quartz sand in an expensive and energy-intensive process .

各企业通过一种昂贵且大量消耗能源的流程从一种石英砂混合物中提取油砂沥青。

Much of the initial investment was in oil sands highly viscous bitumen coated sand deposits found mainly in canada .

最初的大部分投资集中在油砂矿领域这是主要在加拿大发现的一种被高粘度沥青包裹的砂矿。

In their natural state , oil sands are made of quartz sand covered by layers of water and bitumen .

在自然状态下，油砂由石英砂构成，上面覆盖着多层的水和沥青。

Typically it involves drilling wells to pump steam into the ground to melt the bitumen and make it easier to suck up to the surface .

典型的工艺是先钻井，然后通过井眼将蒸汽泵入地下，油砂中的沥青被蒸汽熔化，这样便容易被抽吸至地面。