SINGAPORE, May 15 (Reuters) - Jincheng Petrochemicala newly restructured independent refiner controlled by the Liaoning provincial government in northeastern China, is seeking crude oil import quotas for its three plants, four sources with knowledge of the matter said.

Jincheng Petrochemical has applied to Beijing for quotas to import 15 million metric tons of crude per year, which equates to 300,000 barrels per day (bpd), or about 3% of the shipments the world's largest crude importer brings in.

Jincheng Petrochemical, based in the city of Panjin, was formed by the merger of three refineries in Liaoning province previously owned by private refiner Bora Group and Panjin Haoye Chemical Co, both of which were found to have evaded fuel taxes in a government investigation in 2021.

Jincheng did not immediately respond to a request for comment on the quota request.

The National Development and Reform Commission and Ministry of Commerce, which are responsible for the oil quota system, did not immediately respond to a request for comment.

If the quotas are approved, the additional volumes Jincheng purchases could increase the amount of oil that China buys from Russia, Iran or Venezuela that make up much of the crude consumed by independent refiners such as Jincheng, trade sources said.

Previously state refiner Sinopec Corp was assigned the oil supplier to the plants now run by Jincheng, which have a combined processing capacity of 400,000 bpd, after the previous owners lost their import quotas following the 2021 investigation.

Sinopec's imports are not subject to quota management.

Bora and Haoye were among the targets of an official crackdown on fuel tax evasion and illegal oil quota trading in 2021. The regulatory scrutiny quashed some imports leading to the first annual decline in 20 years in shipments to China that year.

Several other independent refiners were also stripped of import quotas following that probe.

(Reporting by Chen Aizhu and Florence Tan; Editing by Christian Schmollinger)