The widespread corrosion problem in alkylation units and countermeasures

Corrosion in alkylation units indeed poses a serious threat; in the past, weld leaks and valve corrosion frequently occurred in acid-related pipelines and valves. There are several points related to corrosion prevention that are worth noting for reference: 1. Control of the concentration of the reaction acid – maintaining an appropriate acid concentration can reduce corrosion in the pipelines used to transport acid as well as in the acid discharge pipelines. 2. For the selection of materials for relevant valves and pipelines, it is recommended that, except for acid storage tanks, valves and pipelines be made of 304 stainless steel. In particular, for the valves located at the base of equipment that comes into contact with acid, such as acid tanks, reactors, alkali washing tanks, and water washing tanks, it is suggested to use carbon steel. 3. Acid temperature control: Provide heating for the acid pipelines in winter; especially in northern regions, ensure that the temperature does not exceed certain limits, so as to control the acid temperature and reduce the corrosion rate. 4. The production and processing load is usually adjusted based on the company’s economic performance; this isn’t a major issue. However, if the system operates under overload conditions, it’s important to ensure that systems for decarburization, alkaline washing, and water washing are adjusted in a timely manner. 5. When inspecting key points and critical equipment, pay attention to measuring thickness in a timely manner, especially in areas where the flow velocity in the pipelines is high and turbulence is intense, so as to detect issues early and address them promptly.

Corrosion-resistant pumps are recommended for the alkylation process