Issues with liquid caustic storage tanks

No lining is needed; carbon steel is sufficient. However, heat tracing and insulation are required to prevent crystallization.

Carbon steel will do; do not use 300 series materials. Hot water is the best choice for insulation; the heating temperature should not exceed 70°C, otherwise the welds will crack

This post was last edited by foam_ZPTK on 2019-4-23 at 16:53. What field does the original poster work in? Based on your question, carbon steel is sufficient.

It is best to consult experts from design institutes

Is lining with plastic necessary for a carbon steel storage tank containing liquid caustic at a concentration of 36.5? At normal temperature and pressure, with insulation in winter. If it is HaOH, it is a strong base. When stored at room temperature, carbon steel suffers minimal corrosion and can be used effectively. However, using insulation and heat tracing in winter presents problems; under such conditions, the operating temperature should not exceed 60 degrees, otherwise stress corrosion cracking of the weld seam may occur, which is what we refer to as alkali embrittlement. If such operating conditions are unavoidable, heat treatment should be applied to the weld seams of the storage tanks used, so that the hardness of the weld seams and their heat-affected zones is comparable to that of the base material; this will help prevent the occurrence of alkali embrittlement.

Carbon steel is suitable; there is basically no uniform corrosion, but care should be taken regarding stress corrosion cracking.