Zavod Slantsy OAO (former names: Gazoslantsevyi zavod and Slantsepererabatyvayushiy zavod Slantsy, Russian: ОАО «Завод Сланцы») is a petrochemical company based in Slantsy, Leningrad Oblast, Russia. The company was established in 1945 to supply Leningrad with oil shale gas, synthetic gas produced by oil shale pyrolysis. In 1952, the first unit of a 75 MW oil shale-fired power plant and the first stage of the oil shale gas extraction plant was commissioned. Since 1955 until 2000 the plant produced shale oil using Kiviter technology. In addition, it produced other chemical products from oil shale. Oil shale was supplied by the mining company Leningradslanets. In 1970, the company started petroleum coke tempering.