Used motor oil reprocessing is offered also for Latvian conditions. The benefits from it consists in preventing of environment pollution by metal oxides and unknown toxic substances in flue gases, evolving from, or due to possible catalytic synthesis during the waste oil incineration, if the latter was disposed as before. The main such pollutants from Latvian waste oils are sulphur dioxide, Zn, P, Pb, Cr, Ni and Mo oxides, as well believed to be also heavy aromatic hydrocarbons. Besides, the reprocessing completely lifts up the subsoil water pollution danger in case o f waste oil occasional spillage.The used motor oil reprocessing by its recovery, vacuum distillation and marketing is proved to be economically profitable, if the world crude ...