When was Tangshan Coking Plant laid off?

1996. According to the announcement issued by Tangshan Municipal People's Government, Tangshan Huiyuan Coking Gas Co., Ltd. was formerly known as Guye Branch of Tangshan Coking Plant, with an annual output of 6,543,800 tons of coke. 1996 the factory closed down and all the workers were laid off. Later, Tangshan guye district Huiyuan Company bought out Guye Coking Branch as a whole.