Subcritical Solvent Extraction Technology Introduction

Subcritical solvent extraction adopts advanced designed process of those of precious oilseeds. It realizes high efficiency low temperature desolventization, low solvent residual of less than 1% and high oil content. This is complete different extraction methods from formal used 6# solvent. No. 4 solvent (main component of liquefied propane and butane) oil extraction technology is also called subcritical extraction technology. No. 4 solvent oil extraction technology is a complete new oil production technology. It is a somewhat more advanced extraction method than traditional No. 6 solvent oil production line. It has bigger social and economic benefits than No. 6 solvent oil extracting method.

Subcritical Solvent Extraction Processing Line

Features of subcritical No. 4 solvent extraction processing line:
● Normal temperature oil extraction and low temperature desolventization. The featured characteristic cannot destroy the active substance and plant protein in oil extraction. It provides convenient condition for precious oilseed extraction and development of plant protein.
● Low steam consumption. Owing to requirement of normal temperature extraction, there is no need of high temperature evaporation. It reduces nearly 80% coal consumption in extraction process. Thus, it reduces the project investment and industry waste emissions.
● Lower cost than supercritical extraction. The advantage of large-scale oil pressing machine plant has caused it a very popular oil extraction method. It has been fully replaced supercritical technology.

Working principle of subcritical solvent extraction processing line:
This is a more simple and environmental protective oil extraction technology than normal used method. No. 4 solvents are purified from lliquefied petroleum gas, consisting of propane, butane, boiling point is below 0 ℃. Extraction is processing under certain pressure (0.1 ~ 0.7Mpa liquid state) and under room temperature, achieving room temperature oil extraction. Solvent in crude oil and meal removes at a low temperature and vacuum state. Solvent cycles use after liquefaction.

Processing Flow of subcritical solvent oil extraction:
● Oil materials enters into extraction tank   
● solvent pump injects 4# solvent into oil extraction tank for oil material immersion
● solvent pump pumps mixed oil to evaporative tank
● connect extraction tank and suction port of compressor in order to gasify solvent residual in meal, enters into compressor. Solvent flows into solvent turnover tank after compressing, condensing and liquefy in condenser for reuse. Meal discharges from extraction system.
● mix oil enters into evaporation system in order to separate crude oil and evaporate 4# solvent. Evaporated solvent is reused after compressing and liquefy, and crude oil discharges from extraction system.

Featured by low boiling point, pure ingredients, low residual solvent, and low leaching temperature, good selection, crude oil after subcritical solvent extraction are always in good oil quality as well as good quality extracting meal. It has low cost spending on electricity, coal and vapor. It is a very popular and environmental protection project acceptable by more and more users worldwide.