Solvent Vacuum Evaporation System Negative Pressure Evaporator for Extraction

The Solvent Vacuum Evaporation System removes the solvent from the miscella delivered by the oil extractor in order to obtain crude extracted oil. Its main equipment includes the first rising film evaporator, the second rising film evaporator and the disk stripping column. Using the difference in boiling point between oil and solvent, the evaporators heat the miscella so that most of the solvent vaporises and separates from the oil, and using the difference in volatility, the stripping column applies steam distillation to remove the residual solvent. The solvent vapour then passes to the condenser for recovery and reuse.

The system uses negative pressure evaporation technology. The secondary steam from the desolventizer toaster is used as the heat source of the first evaporator, and a steam jet pump pulls a vacuum so that the whole train runs under micro negative pressure. The evaporating temperature is low, the oil quality is good, and both steam and solvent consumption are reduced. An automatic control system keeps the key parameters stable, which lowers the labour intensity and improves the reliability of the extraction workshop.

• Negative pressure operation: the whole train runs under micro negative pressure with a low evaporating temperature.
• Better oil quality: crude oil with a low peroxide value, light colour and residual solvent below 0.02%.
• Heat recovery: the secondary steam from the desolventizer toaster heats the first evaporator, cutting condenser load.
• Disk stripping column: stainless steel disks reduce oil film coking and clean easily by flange connection.
• Solvent saving: less solvent leakage and lower steam and solvent consumption for the workshop.
• Automatic control: key parameters are controlled automatically for stable and safe operation.

The vacuum evaporation system is installed between the oil extractor and the refining workshop in every solvent extraction plant. It processes the miscella from rotocel, loop type, drag chain and tank extractors and delivers crude extracted oil for degumming, de-acidification, bleaching and deodorization, while returning recovered solvent to the extraction line.

The evaporation system is shipped in modular skids with the evaporators, stripping column, condensers and piping protected and braced for sea transport. We provide P and I diagrams, an operating manual and a commissioning service, together with a twelve month warranty on the evaporator shells, stripping column and heat exchangers.