For refining the oil, there are three basic processes in the refinery. First process is neutralizing the oil in the neutralizer to remove the Free Fatty Acids (FFA) by adding caustic soda. Oil is heated upto about 60 C by thermic fluid coils and oil is stirred by stirrer. Then soap stock formed due to chemical reaction is allowed to settle at the bottom of the neutralizer from where it is taken out into soap pan.
Neutralized oil is drawn into the second vessel called bleacher where colour of oil is removed by bleaching process with aid of chemicals such as carbon black and bleaching earth. Oil is generally heated upto 110 C by thermic fluid coils. Stirring is also continued. Bleaching process is done under vacuum.
Bleached oil then goes to the filter press where bleaching earth and chemicals are separated and clean bleached oil is then drawn to deodourizer where oil is heated above 110 C through thermic fluid coils and then live steam is given to the oil from the bottom steam nozzles and temperature of oil is raised upto 200 to 220 C through thermic fluid coils. Entire process is done under high vacuum. Thus smell is removed from the oil in the deodourizer. Then it goes to cooler where water circulating coils take away heat and oil is cooled. Again it goes to second filter press where completely refined and transparent colour less oil is obtained.
Thermic Fluid Boiler, Vacuum Pump, Barometric Condenser, Catchalls, Steam Generator etc. play their role in the refining process. So these equipments are part of the refinery and connected with the vessels through pipelines.
Additional Process for palm oil refinery
Specially for palm oil refinery, fractionation process is required in which palm olene and palm sterene are separated by scientifically cooling the refined palm oil by chilling plant and then filtering the oil. For this purpose crystalizing vessel is used in which chilling pipe coils cool the oil for fractionation. Palm sterene crystals are formed due to chilling which are separated in the filter press and pure liquid of palm olene is obtained and palm sterene cake is retained in the filter press.
Specifications of Refinery
Capacity 5 tonnes per day i.e. 4 batches of 1250 kg. each
1. All the main vessels i.e. two neutralizers, one bleacher and one deodourizer are properly arranged on the first floor of the steel structure. So all these vessels are hanging on the steel strucutre. Just below the two neutralizers, two soap pans are resting on the ground floor in which soap stock is collected. There is a steam pipe arrangement in the soap pans also.
2. Steel structure has size of 14ft. x 14ft. (i.e. 4.25mtr. x 4.25mtr). First floor is 9ft. above the ground level. There are 8 coloumns of double chanel which supports the entire steel structure. It has proper staircase and railing on all the sides of steel structure at the first floor and also on staircase. Two filter presses are also accomodated on the first floor of the steel structure.
3. Two oil tanks i.e. raw oil tank and bleached oil tank are accomodated under the strucutre on the ground floor. Then cooler, thermic fluid boiler, two steam generators, vacuum pump, water pumps, oil pumps and refined oil tank are arranged on the ground floor around the steel structure i.e. outside the square of 14ft. x 14ft. of the steel structure. So total space occupied is about 30ft. * 30ft. (9mtr. x 9mtr.).
4. 40ft. tower is erected just near the deodourizer and its complete structure is supported from the ground floor and also it is attached with the refinery structure. Berometric condenser is arranged at 40ft. height to create proper vacuum.
5. All types of piplines are interconnected as per the requirement of the refinery i.e. oil pipelines (yellow colour), vacuum pipelines (blue colour), steam pipelines (black colour), water pipelines (white colour), thermic fluid pipelines (red colour). At all appropriate places, proper valves are provided in the pipelines.
6. Neutralizer is provided with thermic fluid coil for heating the oil.
7. Bleacher is provided with double pipe coil. One is for thermic fluid and another is for cooling water.
8. Deodourizer is provided with double pipe coil i.e. in both the coils, thermic fluid is circulated. Steam is ejected from the stainless nozzles provided on the steam pipe cross supported at the bottom.
9. Cooler is provided with double pipe coil. Both for cooling water.
10. In every vessel temperature guage is provided. Vacuum guage is provided on deodourizer, bleacher and cooler.
11. Neutralizer is open on the top having conical bottom.
12. Bleacher has dished ends on both the sides. Similarly deodourizer has dished ends on both the sides. Cooler has also dished ends on both the sides.
Specification of Refinery with fractionation Process
13. There will be chilling plant for fractionation process which will include shell and tube chiller, compressor, motor, pump, condenser, control panel box etc.
14. Crystallizing unit which is similar to neutralizer complete with chilling coil.
15. Filter press for separation of palm olein and palm sterene.