Reaction section

The naphtha hydrodesulfurization (HDS) process in the refinery has a reaction section which is a heating and cooling thermal process consisting of a feed-effluent heat exchanger and a fired heater. Energy savings are fundamentally made as a result of the maximized heat recovery in the heat exchanger and the reduced heat duty of the fired heater. To achieve further energy saving in the process, “self-heat recuperation technology” (SHRT) was adopted by a naphtha HDS process with the capacity of 18,000 barrel per stream day (BPSD). A compressor was introduced in this technology. The suction side of the compressor needed lower pressure so that the feed stream could evaporate more easily. The discharged side of the compressor satisfied the operating conditions of both pressure and temperature at the inlet of the reactor. And the reactor effluent stream was able to be used completely to preheat and vaporize the feed stream. All the heat in the process stream was recirculated without the necessity of a fired heater. It was confirmed that despite there being no more energy saving potential in the conventional process that makes use of a fired heater, the advanced process based on SHR can reduce the energy consumption significantly by using the recuperated heat of the feed stream.