In the past,distillation has always been too expensive; but a great deal of success in cheapening the process has been achieved in the last few years. Some clever ideas have been thought out to do this.

• 过去，蒸馏一直是很昂贵的，但在最近几年里，在降低蒸馏的成本方面取得了巨大的成功，现在已有了一些好办法来做到这一点。