Huaxing Petrochemical recently conducted technical renovations of the heat exchange system of a 1.4-million-ton gasoline and diesel oil hydrogenation unit. The move not only raised the technical process stability but also brought down fuel gas consumption from 1,100 to 855 cubic meters per hour, saving 4.6 million yuan ($740,000) in costs annually.
The renovation offered greater room for raw oil temperature adjustment and raised flexibility in winter operations. In addition, it increased temperature of other mediums that exchanged heat with raw oil, which effectively avoided heat exchanger blocking caused by ammonium salt precipitation. The renovation helped maintain system pressure difference in a reasonable range and made operations more stable.