我厂是以重油为原料生产尿素的中型氮肥厂,原设计生产能力为年产合成氨5万t,尿素8万t,于1974年建成投产。1988年进行了二期技术改造,1990年10月投产,现在生产能力已达到年产合成氨12万t,尿素20万t。1　我厂“油改煤”情况近几年来,由于各炼油厂竞相上了重油深加工装置,使重油资 Our factory is a medium-sized nitrogenous fertilizer plant that uses urea as raw material to produce urea. The original designed production capacity is 50,000 tons of synthetic ammonia and 80,000 tons of urea annually. The plant was put into operation in 1974. In 1988, the second phase of technological transformation was carried out and put into operation in October 1990. Now the annual production capacity has reached 120,000 tons of synthetic ammonia and 200,000 tons of urea. 1 I plant “oil to coal” situation In recent years, as the refinery competing on the heavy oil processing plant, heavy oil