The treated fuel has reduced levels of vanadium, nickel and other metals.

处理过的燃料中钒、镍和其它金属的含量降低。

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Because they are bigger and heavier like trucks, SUVs are treated more leniently by government rules on fuel efficiency and emissions.

NPR: China's Struggling Automakers Jump On SUV Boom

However, fuel laundering - where the lower-taxed agricultural diesel is treated and sold for road use - remains a very profitable business.

BBC: Fuel laundering 'costs tens of millions' to governments