Industrial waste gas is hereby classified into three categories that are Sulfur dioxide, smoke and dusts.

工业废气按物质分为三种：二氧化硫、烟尘、粉尘。

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"Hence, as greater investment from China, Saudi etc. leads to more industrial development, owners, investors and managers need to be agile and not waste days on what should be a three-hour flight, " he adds.

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