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Happy Seas and Rivers, a Happy New Year! ------------------------------ Recently, the **Energy Bureau announced 14 advanced technologies for energy savings and carbon reduction in the refining industry, along with 12 typical cases. The “300,000 tons per year ethylbenzene plant process hot water waste heat recovery project” submitted by CNOOC Daxie Petrochemical was successfully included in the list of typical cases. This is another prestigious recognition following its selection as a typical case in industrial energy conservation technology by the **Ministry of Industry and Information Technology** and the **Energy Conservation Center**. After the commissioning of the Phase III project at Daxie Petrochemical, the medium-temperature hot water at 120°C generated by the 300,000 tons per year ethylbenzene plant was directly integrated into the plant’s low-temperature hot water system at 95°C, resulting in the waste of heat in the 120–95°C range. Meanwhile, the 0.35 MPa steam required by the styrene plant is supplied at a rate of 15 t/h through steam temperature and pressure reduction at 1.0 MPa, resulting in an inefficient utilization of the steam cascade. There is an excess of low-temperature hot water throughout the plant, requiring 4,000 t/h of circulating water for cooling. To address these issues, Daxie Petrochemical adopted Class II absorption heat pump technology to convert the low-quality process hot water from the ethylbenzene unit into high-quality 0.35 MPa steam, thereby resolving the problems of unreasonable stepwise utilization of the 1.0 MPa steam in the styrene unit as well as the excess of low-temperature hot water throughout the plant. After the project is put into operation, it can save 9,000 tons of standard coal per year, reduce carbon dioxide emissions by 24,900 tons, save 15 million yuan in steam costs, and increase the utilization rate of low-temperature heat across the entire plant by 16.3%.