Kurita's ACF Technology prevents fouling and corrosion.
Ammonium salt fouling is an omnipresent threat in oil refineries. It may lead to insecure operational conditions with high production losses. Salt deposition is frequently detected in fluid catalytic cracking main fractionator columns. Higher chloride concentrations in residue feedstocks can initiate ammonium salt fouling. Low main fractionator top temperatures of fluid catalytic cracking units will increase the fouling risk. Negative impacts are increased pressure drop, flooding of the top section and production losses. Heat recovery is essential at process units, which are operated with reactors. Typical process units, where ammonium salt fouling or corrosion occurs are hydrotreaters, hydrocrackers and catalytic reformers. Feed/effluent exchangers of hydroprocessing units and the stabiliser columns are equally affected.
The new ACF (Ammonium Chloride Free) technology uses the benefits of a chemical programme. ACF additives are liquid formulations with a very high base strength. ACF reacts immediately with strong acids such as hydrochloric acid. The strong base ACF displaces the weaker base ammonium chloride or ammonium bisulfide from its salts. The ACF reaction products have a neutral pH and very low corrosion potential. Compared to that situation an ammonium salt has a very high corrosion potential.
The technology also incorporates a high moisture absorption property (very hygroscopic). ACF salts can absorb moisture from the surrounding steam to keep the formed ACF salts liquid. This prevents ammonium salt fouling and corrosion in crude distillation units, catalytic cracking units (FCC), hydrotreaters, hydrocrackers, reformer units and other process equipment.
The innovative treatment is based on several actions:
- The very strong organic base reacts immediately with strong acids by forming a liquid ACF chloride salt.
- Ammonia is released from the ammonium salt by forming the corresponding liquid ACF salt.
- The ACF reaction product has a neutral pH, is very hygroscopic and can be removed easily with water.
What are the benefits that ACF Technology offers?
- Prevention of salt fouling and corrosion by forming liquid ACF salts. These salts have a neutral pH and very low corrosion potential.
- Removal of already formed ammonium salt deposits during operation.
- Immediate reaction with very corrosive hydrochloric acid and ammonium salts.
- Formed ACF salts can be easily removed with wash water or sour water. Liquid ACF salts are hygroscopic and have a very low corrosion potential.
- Ensures a long lifetime of the process equipment.
- Reduces the need for cleaning operations.
