Causes of corrosion of conversion equipment
Thread Content
Our unit has newly converted to a medium to low flow process. Various heat exchange equipment often leaks due to corrosion, focusing on the manholes and connecting joints. We think it is caused by poor mixing and water inclusion when adding steam at the outlet of the saturated tower. We plan to add a mixer for the next maintenance. Please heroes, please analyze and analyze whether there are other reasons.
The semi-water gas coming out of the saturated tower contains acidic gases such as hydrogen sulfide and carbon dioxide, as well as oxygen, water vapor, mist water, etc. Water and acidic substances are prone to electrochemical corrosion, so the landlord should pay more attention to the PH value of the water in the hot water circulation.
Uneven steam mixing will aggravate corrosion, and the investment is very small. It is recommended that the owner add a mixer at the outlet of the saturated tower after passing through the steam-water separation tank.
I think it is caused by water at the outlet of the saturated tower. A separator should be added. It is best to add superheated steam, otherwise there will be a small amount of condensation. Adding or not adding a mixer will have little effect. We do a lot of medium and low conversion and various heat exchange equipment.
I don’t know if it’s a sulfur-tolerant transformation? What should be considered in the corrosion resistance of sulfur transformation is the selection of equipment or the process of installing the equipment. Is the cladding lining in the sulfur-resistant transformer tower not in place?
Since 1998, we have been using conversion devices with medium and low flow rates, and there have been leaks, but not many. The reasons for corrosion and leakage of various equipment are different. First, the water quality and steam quality must be controlled to meet the standards. In manholes and nozzle joints, corrosion is mostly caused by frequent changes in cold and heat. Corrosion can even occur in the upper section of the saturated tower. ； Water cooler corrosion may be caused by acid corrosion and corrosion of stainless steel pipes by chloride ions in circulating water at high temperatures. The causes of heat exchanger corrosion include problems with the heat exchanger design, improper heat exchange area, and partial water vaporization, causing vibration and erosion of the heat exchange tubes. ； Heat exchanger expansion and cracking ； Dew point corrosion, etc.
It is mainly the electrochemical corrosion of acidic substances in the gas at the dew point temperature, such as hydrogen sulfide, carbon dioxide, oxygen, etc. Precautions: 1. Do a good job in internal anti-corrosion of equipment. 2. The pipes in the dew point temperature zone are made of stainless steel. 3. Ensure the insulation and drainage of equipment pipelines. 4. Ensure that the pH value of the water in the hot water cycle is 7-9. This post was last edited by 7276166 on 2009-3-14 19:32 ]
study* . Is your method of controlling pH by adding ammonia?