Anti-corrosion alloy for Petrochemical plant.（HY-industry technical centre）
In order to strengthen the safety factor of the refining unit and improve the competitiveness of the business, the reliability of the refining unit and equipment must be improved. Oil spillage not only seriously affects the ecological environment, but the refinery will also be subject to huge fines. The use of anti-corrosion alloy can reduce the new Equipment installation costs extend the life of existing equipment, thereby increasing profits for oil refining companies. The following introduces the use of several anti-corrosion alloy that have been confirmed in the project since the establishment of Shanghai HY Industry Co., Ltd.
Crude oil distillation unit
By taking some improvement measures, the service life of the atmospheric fin equipment at the top of the atmospheric tower of the crude oil distillation unit can be extended. In order to solve the problem of corrosion and pitting corrosion of monel pipe, HASTELLOY C-276 alloy sleeve can be installed on the side contactor, or a liner can be installed inside the pipe. The liner diameter is about 1 inch and the thickness is 0.020 inch. After the installation is completed, the tail end that is elongated by hydraulic pressure is cut off. All processes are carried out at the place where the air fins are located. Currently, four oil refineries have been installed with linings in the early HY-Industry project, as in March 1999, NACE International According to the Corrosion Association of the Refining Industry, “This is an inexpensive way to extend life.” The downside is that there is a unit of heat conveyor that increases the load by about 10%. This may be due to the corrosion on the C-276 alloy liner, and there are no problems in the other three crude oil distillation units.
In the vulcanization plant or vulcanization plant, the hydrogen sulfide recovered from various refinery steam is converted into elemental sulfur. When hydrogen sulfide is combusted, due to high temperature corrosion, the service life of the traditional Anti-corrosion alloy burner nozzle is shortened. In September 1991, a new HAYHES HR-160 alloy burner nozzle was installed on a new project in HY-Industry. This nozzle can increase the service life of the burner nozzle from one year to more than 8 years. This type of nozzle is still in use and is expected to be used by the end of 2025.
Acid water stripping tower
In an acid water absorption tower of a refinery, the C-276 alloy liner was installed inside the existing aluminum tube in 1995, including the tower top tube, air fins to the distillate tank tube and return pipe, C-276 alloy The lining completely solves the problem of corrosion caused when using aluminum tubes. In the second half of 1999, HY-Industry added a HASTELLOY C-276 alloy elbow, and another installation using C-276 alloy in January 1987 Circulation pumps (box and impeller) are still in use to date. The comparison results show that the use of carbon steel, plastic products, ordinary stainless steel and other alloy products are not as satisfactory as HASTELLOY C-276.
The device will produce some corrosion on the acid-resistant carbon steel regenerated stripping scrubber. According to HY ’s years of experience, C-276 alloy should be used internally in this stripping scrubber. HY-Industry installed C-276 alloy composite carbon steel scrubber in the renovation project in 1982. Shows good results, so a new regenerated stripping scrubber composed of C-276 alloy composite carbon steel was born, and was installed and used by a new project in 1986, and was patented by HY-Industry. Proven to have excellent performance.
In the catalytic reformer, the 304SS chlorine and sulfur injection sleeves are easily corroded, so HY replaced it with a C-276 alloy sleeve in 1983, which proved to have a good use effect. Because other high-nickel alloys are easy to cause corrosion problems, C-276 alloy strip liner was installed in the alkaline washing part and water washing tower in the 1990s. Although the liner connection is good, it is required to repair cracks and welds in the weld. Small hole, in July 2000, install C-276 alloy tray ring and tray in HASTELLOY C-22 alloy welded pipe, remove the worn-out monel 400 alloy, and use C-276 alloy welded layer in the alkaline washing part.