Technical Problems And Solution of Vegetable Oil Solvent Extraction
Main purpose of vegetable oil solvent extraction is to extract oil from pressed or prepared oil cake ,finally get crude oil and meal. How to control vegetable oil solvent extraction is directly related with the quality of crude oil and final meal, oil yield, production cost and safety. As a professional manufacturer of vegetable oil extraction machine, we know that there are still some problems existing in this industry and we will give some solutions accordingly.
1. Control oil residue inside meal
Oil residue inside meal is one important index in vegetable oil extraction, because it is direclty affecting profit of one oil plant. With certain vegetable oil extraction equipment , oil residue inside meal is depending on quality of pressed oil cake and specific operating process.
a. Problem of pressed oil cake
Some oil plants buy pressed oil cake from others which is difficult to control oil contain and degree of power. Or when production capacity increases, quality of pressed cake is lower than before, mainly are too high oil contain ,loose structure of cake etc. When vegetable oil solvent extraction, it's difficult to reduce concentrate of mixed oil with bad solvent penetrability resulting in higher oil residue inside meal.
To solve this problem, basic method is to control strictly oil pretreatment or oil pressing process,for example, to make good flaking, control steam temperature and time to make sure oil contain of pressed cake about 15%, moisture less than 5%,which will make good penetrability of solvent and help solvent extraction and reduce oil residue inside meal.
b. Problem of operation
Solvent oil extraction is finished inside closed oil extractor, it's difficult to observe process of oil extraction during operation. And also because of different level of qualification of workers , some of them don't know how to adjust and solve problem according to different quality of raw material and solvent extraction specification.
So, first we need train workers to make them know better different factors affect oil extraction in order to analysize and solve different technical problems. For example, when oil contain inside cake is too high, should increase proportion of solvent to reduce concentrate of mixed oil, or prolong extraction time to make sure thorough extraction, or preheat new solvent at a certain higher temperature.all of these can increase efficiency of oil extraction and improve effects of vegetable oil extraction.
2.Control solvent loss
Solvent loss can be divided into unavoidable and avoidable loss. Unvoildable loss includes limited quantity brought by exhaust gas, meal, crude oil and waste water , normally about 0.5-1.5kg per ton of material. Avoidable solvent loss is happened in solvent escaping,emitting, dripping or leaking etc.
a. Control unavoidable solvent loss
When discharge exhaust gas,to control exhaust gas temperature and concentrate to make sure discharging exhaust gas with concentrate below 0.1%.
Most solvent is taken away by wet meal, then strictly operation of desolventizer is most important measure to reduce solvent residue inside meal.
Strictly control temperature of second evaporation and stripping to control solvent residue inside crude oil below 500mg/kg.
Small quantity of solvent is dissolved or emulsified inside waste water and taken away. We need control waste water discharging temperature and good purifying before evaporating mixed oil.
b. Control avoildable solvent loss
Enhance examine and maintain pipes of vegetable oil extraction equipment periodly, to make sure no leakage in connections.
Keep whole system under micro-negative pressure to make pressure balance among each oil extraction equipment.
Keep continuous production , reduce temporary stops of production.
3.Control break down and damage of vegetable oil extraction equipment
Most complicate problem is oil extraction equipment problems. Once breaking down of oil extraction equipment, all production of vegetable oil should be stopped which will make loss. And oil extraction workshop is no-flame and anti-explosion workshop which is difficult to solve problems
So we need make good record of oil equipment working situation , and periodly examine and repair equipment to make sure safety during oil production.
