Rape oil esters FAME


Author: Lech Hys, Krystian Klementowicz  www.krystian.us

The whole process of producing fatty acid esters of rape seeds consists from three separate technologies:
1    Technology of winning raw oil from rape seeds by extraction,
2    Technology of preparing vegetable fat for estrification
3    Technology of flow estrification of vegetable oil.
List of techniques and technologies protected by copyright and invention rights

1.    Method and device for producing liquid fuels – Patent No. PL 196514- owner: Lublin Polytechnics, authors: J. Sawa, L. Hys.
2.    Structural solutions of the flow extractor – copyright reserved for the offerer

Process description

The main operations of this process are:
1    Separation of rape seeds from dirt,
2    Crushing of seeds,
3    Extraction of oil from seeds using extraction naphta,
4    Filtration of miscellas,
5    Separation of solvent from oil by distillation,
6    Condensation of solvent vaopurs and returning it ti the extraction process,
7    Filtration and storage of oil.
The oilless meal is briquettet as a fuel used for generating heating steam or as a product for sale.

This technology enables:
1    increasing oil output – up to 98 % compared with pressing with an expeller – up to 92 %,
2    reduction of power consumption of the process (an expeller of 1 Mg/h capacity  – 120 kW of installed power, extractor- up to 20 kW),
3    reduction of investment costs (expeller > 750,000 PLN (2002)) –
The method of extracting oil from crushed seeds is used in commercial scale of production of biodiesel fuel e.g. in India.

List of techniques and technologies protected by copyright and invention rights

1.    Method of purifying fatty acid esters and a mean for that purpose. – patent application No. P 380090, (author: L. Hys) copyrights reserved
2.    Processing line for preparing vegetable oil for estrification and its use – copyrights reserved.
3.    Structural solutions of the flow extractor – copyrights reserved

Process description
The essential thing of preparing raw oil for estrification is to separate solid particles and water, neutralization and degumming.
Compared to a classic rafination of edible oil no deodoration and bleaching take place.
The applied process of preparing oil to transestrification is base on a method of extracting free fatty acids, water and phospholipids using a specially prepared extractant.

The oil after processing or subject to processing may be used for industrial purposes only.

The raw oil preparation process consists of following unit stages:
1    Preparation of an appropriate extractant composition.
2    Preheating of oil.
3    Filtration of oil.
4    Extraction of free fatty acids and phospholipids in liquid-liquid system with use of a flow extractor.
5    Separation of oil and depleted extractant by swirling in a plate separator.
After this process the oil flows to the transestrification unit.
The depleted extractant flows into the storage tank.
The extractant may be regenerated to be used again.
List of techniques and technologies protected by copyright and invention rights of the offerer

6.    Method of continuous production of fatty acid esters especially as engine or heating fuels or components for producing them –  patent application No. P 379428, (authors: K.Klementowicz, L.Hys) copyrights reserved
7.    Method of purifying fatty acid esters and a device for that purpose. – patent application No. P 380090, copyrights reserved
8.    Processing plant for production of fatty acid esters of specially prepared vegetable oil and its operation – copyrights reserved.
9.    Structural solution of the transestrification reactor unit  – copyrights reserved

Process description

The offered technology of a continuous production of FAME from specially prepared rape oil consists of following functional blocks:

1.    A block for preparing raw substances, where KOH is diluted in methanolu and then the solution is stored and the oil is preheated.
2.    A block for transestification, where a flow premixing of preheated oil with the KOH occurs and then the mixture flows to the group of flow reactors, where radicals of methanolize reaction are realized and transestrification occurs.
3.    A block for phase separation, where ester and glycerine phases, formed in the reaction, are separated during a flow through the gravitational separator. The ester phase runs to the soap forming block and the glycerine phase runs to the glycerine phase treatment block.
4.    A block for soap formation. Soaps formed during reaction between KOH and free fatty acids and soap ester are separated from the ester phase by a liquid-liquid extraction. To fully discharge soaps from the system a two stage flow extraction is carried out and after that phases of ester and soap containing extractant are separated by swirling. In the first extraction stage the regenerated extractant is used and in the second one a fresh one. The ester phase is lead to the methanol distillation block and the extractant phase to the extractant regeneration block.
5.    A block for releasing methanol from the ester phase followed by distilling of methanol remaining in the esther. The methanol condensate is returned at the beginning of the process. The methanol-free esther is directed to the sorption block.
6.    A sorption block as an option, where the ester passes through a solid deposit of sorbent to catch remains of soap, water traces, triglycerides, methanol and other impurities from the ester. After exit from the sorption block the ester is stored. The used sorbent can be regenerated.
7.    A block for treating the glycerine phase to recover methanol by distillation and then, after an acidifying, for separating the system into two liquid phases: the olein (FFA) and glycerine phase and a phase of formed potassium salt.
8.    A block for extractant regeneration, where after acidifying the FFA phase, the potassium salt and the regenerated extractant are released.

Consumption of materials and energy per 1 Mg of product.

No.    Agent    Consumption
1.    refined oil    1080 dm3 (1.0 Mg)
2.    metjanol    150 dm3
3.    KOH    8 kg
4.    extractant    6 dm3
5.    sorbent (as option)    ~  1 kg
6.    phosphoric acid     20 kg
7.    electricity    ~ 10 KWh/T
8.    heating steam    ~ 75 kg/T
These figures may vary depending on quality of used materials

Apart from the FAME, the following substances are formed during production process:


–     raw glycerine 85-88 % in amount of ca. 0,120 Mg/ 1 Mg of FAME,


–     sediment of potassium phosphate containing several weight percent of methyle esters and glycerine in amount of ca. 0,021 Mg/ 1 Mg FAME; this sediment can be used as component of fertilizer due to easy biodegradation of contained esters,


–    oleine (FFA) in amount of ca. 0,014 Mg/1 Mg FAME