Control criteria for silicon content in the feedstock of hydrocracking units

Analysis and Solutions for Excessive Silicon Content in the Feedstock of Hydrocracking Units. The issue you’ve raised regarding the excessive silicon content in the mixed feedstock of hydrocracking units (10 ppm versus the standard of 1 ppm) indeed needs to be addressed promptly. The following are analyses from various perspectives along with suggested solutions: Analysis of the reasons for excessive silicon content. Issues related to crude oil sources: Some crude oils (such as those from the Middle East) naturally contain high levels of silicon compounds. Insufficient efficiency of electrodesalination: Water-soluble silicon compounds are not effectively removed. Introduction of silicon from feedstocks used in catalytic cracking units: Secondary processed feedstocks such as catalytic cracking slurry may contain silicon. Use of process anti-corrosion agents: Certain silicon-based defoamers or corrosion inhibitors may introduce silicon. Specific measures to reduce silicon content. 1. Optimization of crude oil selection and blending: Choose crude oils with low silicon content; optimize the mixing of crude oils by combining high-silicon and low-silicon oils in appropriate proportions to reduce the overall silicon level. Strengthen analysis of crude oil entering the plant: Establish a monitoring system for silicon content to prevent high-silicon crude oils from entering the plant. 2. Improving the efficiency of electrodesalination in atmospheric and vacuum distillation units: Optimize operating parameters – increase the desalination temperature (recommended range: 120–140°C), adjust the water injection rate (usually 4–6%), and optimize the pressure difference across the mixing valve (0.7–1.4 bar). Improve demulsifiers: Use demulsifiers that are effective against silicon compounds; adjust the amount and injection point of demulsifiers. Equipment maintenance: Check the condition of electrode plates, ensure proper functioning of the mixing valve, and clean the desalination tanks regularly. 3. Process adjustments and feedstock management: Control the proportion of secondary processed feedstocks: Reduce the use of high-silicon secondary feedstocks such as catalytic cracking slurry. Optimize distillation cut points: Adjust the side-stream extraction in atmospheric and vacuum distillation units to prevent the accumulation of silicon compounds in hydrocracking feedstocks. Strengthen feedstock monitoring: Install online silicon content analyzers before the hydrocracking feedstock buffer tanks. 4. Emergency response measures: Short-term strategies: Reduce the processing capacity of the unit to lessen the burden on the catalysts; slightly increase the reaction temperature to compensate for any loss in catalyst activity; monitor products closely to ensure their quality. Catalyst protection: Consider using silicon capture agents if available; prepare plans for catalyst replacement or regeneration. Long-term preventive measures: Establish a comprehensive database on the silicon content in crude oils and feedstocks; develop operational procedures and emergency plans for silicon content control; regularly assess the performance of the electrodesalination system and carry out technical upgrades when necessary; communicate with catalyst suppliers to understand catalyst operation strategies in the presence of high-silicon feedstocks. Silicon contamination can cause permanent deactivation of hydrocracking catalysts; it is recommended to take the above measures as soon as possible to reduce silicon content to below 1 ppm in order to protect expensive catalyst systems.

The analysis is too comprehensive. Could you provide some information on “silicon capturers”?

The analysis is too comprehensive. Could you provide some information on “silicon capturers”?

The analysis is too comprehensive. Could you provide some information on “silicon capturers”?