In the oil and gas industry, heating and cooling of oil products, factory gas purification systems, condensation cooling of overhead gas, heating and dehydration of crude oil, treatment of acidic water, heat recovery, etc. Plate heat exchangers or plate and shell heat exchangers are generally used.
Applications:
At the top of the catalytic cracking fractionation tower, the plate heat exchanger can replace the shell-and-tube heat exchanger for oil and gas hot water heat exchange. For example, the top of a catalytic cracking fractionation tower of a refinery adopts three-stage cooling. The first stage is heat exchange between oil and water and hot water. It is operated in parallel by 8 tube-and-tube heat exchangers with a diameter of 1.2 m. The second stage is an air cooler. The third stage is a circulating water cooler, which is operated in parallel with 8 diameter 1.4 m shell-and-tube heat exchangers.The key to the analysis of the problem is: due to the need of process anti-corrosion, a large amount of water is injected in front of the inlet line of the primary heat exchanger, which reduces the quality of the hot water. After design comparison, 3 compact plate heat exchangers are used instead of 8 tube and shell Heat exchanger.
Comparison of the original shell-and-tube heat exchanger with the replacement compact plate heat exchanger:
| tube and shell heat exchanger | compact plate heat exchanger | |
| Quantity | 8 sets | 3 sets |
| The hot water outlet temperature of the primary cooler, Customer expectations: ≥95°C | 90℃ | 97℃ |
| Three-stage cooler Cooled tower Top oil and gas temperature, customer expectation: ≤40°C | ≥42℃ in summer | ≤40℃ |
| Equipment material | Carbon steel, the top of the sulfur is easily corroded | SS 316L , no need to worry about sulfur corrosion at the top of the tower |
| Heat transfer efficiency | Low | Higher |
| Floor Space | Big | Small |
| Cost | Equipment and valve pipeline costs, installation costs, etc. are higher | he total price of the equipment is equivalent to the former. Due to the small quantity, the valve pipeline cost and installation cost are much less. |