Dry fractionation process and system for high-solid-index grease

Abstract

A dry fractionation process for high-solid-index grease comprises the following steps: a, raw oil at the temperature of T1 enters a pre-crystallization tank for pre-crystallization, and the pre-crystallization temperature is T2; b, filling the pre-crystallized raw oil in a membrane filter press, and cooling the raw oil in the membrane filter press after filling until the raw oil is cooled to a final temperature T3; c, starting an extrusion system of the membrane filter press to extrude the raw oil to obtain fractionation liquid oil and stearin, and purging a filter chamber after extrusion is finished; wherein the value range of T1 ranges from 40 DEG C to 50 DEG C, the value range of T2 ranges from 10 DEG C to 35 DEG C, and the value range of T3 ranges from 10 DEG C to 25 DEG C. The membrane type filter press can give consideration to extrusion and crystallization, pre-crystallized oil with a good flowing type is conveyed into the high-pressure membrane type filter press through a pump, pre-crystallized raw oil is subjected to program control cooling through cooling water, finally, the final temperature is reached, extrusion is conducted again, the automation degree is high, and the PKS yield is high.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and fat fractionation, and particularly relates to a dry fractionation process and system for high solid index oil and fat. BACKGROUND

[0002] In the early fractionation process of high solid index oil and fat, such as palm kernel oil, in a typical dry fractionation process, the palm kernel oil is pre-cooled to about 27 DEG C and is divided into many trays, and then is placed for about 10 hours at a temperature of 18 to 21 DEG C to crystallize, the semi-solid palm kernel oil containing fat crystals is wrapped with filter cloth, and the wrapped semi-solid palm kernel oil is filtered under pressure (using a hydraulic machine) to separate the solid from the liquid phase (''special fat and cocoa butter''). In order to increase the yield of palm kernel stearin, the pre-cooled palm kernel oil needs to be placed in the tray sufficiently to increase the amount of fat crystals. This also brings difficulties to the filtration (separation of liquid phase from solid), and in order to recover high-quality fat crystals, it is necessary to use a hydraulic machine to press the cake containing fat crystals under high pressure for a long time.

[0003] In the above-mentioned conventional process, a large number of trays are needed in the crystallization standing step (generally 10,000 to 20,000 trays are needed for processing 100 tons of palm kernel oil per day), the equipment cost is extremely high, and it is impossible to avoid the non-uniform temperature of each tray in the atmosphere, and it is also difficult to control the crystallization temperature and time, thereby causing the problem of unstable product quality. In addition, when the steps from standing to pressurized filtration are examined in detail, various steps are also needed, such as taking out the cakes containing solid or semi-solid fat crystals from the respective trays, individually packaging them, transferring the packaged cakes, and then laying them in the hydraulic machine. These steps are difficult to automate, and a large amount of labor is needed, and about 70 to 80 people are needed for an equipment processing 100 tons of palm kernel oil per day. Therefore, from the economic point of view, the conventional process is not suitable.

[0004] In order to overcome the disadvantages of the above-mentioned oil and fat dry fractionation, such as the lack of flowability of the crystallization, the large investment of the large refrigeration room using trays, and the waste of energy, the process needs to be improved. SUMMARY

[0005] In view of the technical problems existing in the prior art, the purpose of the present application is to provide a dry fractionation process and system for high solid index oil and fat, which can take into account the flowability and the yield of PKS.

[0006] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme: a dry fractionation process for high solid index oil and fat, comprising the following steps,

[0007] a. The raw oil at temperature T1 enters the pre-crystallization tank for pre-crystallization at temperature T2.

[0008] b. The pre-crystallized feed oil is fed into the membrane filter press. After the filling is completed, the feed oil in the membrane filter press is cooled until the feed oil is cooled to the final temperature T3.

[0009] c. Start the extrusion system of the membrane filter press to extrude the raw oil to obtain fractionated oil and stearin. After extrusion, purge the filter chamber.

[0010] Among them, the value range of T1 is 40-50℃, the value range of T2 is 10-35℃, and the value range of T3 is 10-25℃.

[0011] Using this method, the membrane filter press can handle both extrusion and crystallization. The pre-crystallized oil with good flowability is pumped into the high-pressure membrane filter press and filled into the filter chamber. Cooling water then enters the extrusion chambers on both sides of the filter chamber to cool the pre-crystallized raw oil under programmed control, gradually controlling the crystallization temperature and time until the final temperature is reached. Then, extrusion is performed to achieve solid-liquid separation. This method has a high degree of automation and high PKS output.

[0012] As a preferred option, the feedstock oil is palm kernel oil, palm kernel liquid oil obtained from secondary fractionation, shea butter, or intermediate fractionation product of palm oil.

[0013] As a preferred option, the fractionated oil obtained in step c, or the fractionated oil obtained in step c mixed with the feed oil, is transported to a pre-crystallization tank, and steps a, b, and c are repeated to obtain secondary fractionated oil and stearin.

[0014] As a preferred option, the value of T2 is in the range of 21-27℃, and the value of T3 is in the range of 17-21℃;

[0015] When the raw material oil is palm kernel oil, the value range of T2 is 21-25℃, and the value range of T3 is 18-21℃.

[0016] As a preferred option, in step c, the terminal extrusion pressure of the membrane filter press is 6-28 bar; when the raw material oil is palm kernel oil, the terminal extrusion pressure is selected as 16-20 bar.

[0017] As a preferred option, in step b, chilled water is used to cool the pressure medium of the membrane filter press. The cooled pressure medium then enters the extrusion chamber of the membrane filter press and is discharged, thereby cooling the raw oil in the filter chamber.

[0018] As a preferred option, the separated fractionated oil is returned to the pre-crystallization tank, and the solid content after pre-crystallization is controlled to be 20% to 50%.

[0019] As a preferred option, in step b, the filling process is determined by the appearance of liquid oil at the liquid oil outlet of the membrane filter press. When the filter chamber is determined to be full, the filling process ends. During the filling process, the liquid oil flowing out of the liquid oil outlet of the membrane filter press is returned to the pre-crystallization tank in step a.

[0020] After filling is completed, purge the oil inlet pipe of the membrane filter press to purge the oil into the purge tank;

[0021] In step c, after the extrusion is completed, the filter chamber of the membrane filter press is purged, and the oil is purged into the purging tank.

[0022] As a preferred embodiment, after the filter chamber is purged in step c, the membrane filter press is opened, and the separated stearin falls into the stearin tank below the filter chamber of the membrane filter press.

[0023] Hot water or steam is used to heat the stearin bath, and the temperature of the molten oil in the stearin bath is controlled at 40-50℃. The melted stearin is then transferred to the stearin container.

[0024] A dry fractionation system for high solids index oils includes,

[0025] Raw material tanks are used to store raw oil.

[0026] The first heat exchanger is connected to the raw material tank via a fluid conveying device to pre-cool the raw material oil output from the raw material tank;

[0027] The pre-crystallization tank is connected to the first heat exchanger via a fluid conveying device to cool and crystallize the raw oil output from the first heat exchanger.

[0028] A membrane filter press is connected to a pre-crystallization tank via a fluid conveying device to squeeze the pre-crystallized raw oil to achieve solid-liquid separation.

[0029] The liquid oil tank is connected to the membrane filter press via fluid conveying equipment and is used to store the separated extract liquid oil.

[0030] Stearin tank, connected to a membrane filter press, is used to hold the separated stearin;

[0031] A hot water tank, connected to a stearin tank via a hot water pipe, is used to heat the stearin inside the tank.

[0032] The squeeze tank, connected to the squeeze chamber of the membrane filter press, is used to provide pressure medium to the membrane filter press and to cool the filter chamber through the cooled pressure medium;

[0033] Purge tank, used to store the liquid oil purged out;

[0034] Chilled water circulation equipment is used to supply chilled water to the system;

[0035] The raw oil in the raw material tank enters the pre-crystallization tank after passing through the first heat exchanger. Then it is transported to the membrane filter press through the fluid conveying equipment. After filling, the filter chamber is cooled by the pressure medium in the squeeze water tank, so that the raw oil in the filter chamber is further crystallized. Then the squeezing program of the membrane filter press is started to separate stearin and fractionated oil.

[0036] In summary, the present invention has the following advantages:

[0037] (1) By adopting a pre-crystallization tank and then using a membrane filter press to achieve solid-liquid separation, it is not necessary to build a large area of ​​cold room, which reduces the investment cost of building and large cold room equipment, and also saves the operating cost of cold room; it does not require a large number of pallets and supports, pallet transportation equipment and mixing and crushing equipment, which reduces fixed asset investment and corresponding equipment operation failures, and also reduces the annual maintenance cost of equipment and facilities.

[0038] (2) By pre-crystallizing in a pre-crystallizing tank and further cooling and crystallizing in a membrane filter press, the fluidity of the raw oil before it passes through the membrane filter press can be guaranteed, which facilitates the transportation of the raw oil, is conducive to the automated operation of the entire system, and can also achieve a higher PKS output, thus balancing output with costs of manpower, equipment, and construction.

[0039] (3) By returning a certain amount of fractionated oil to the pre-crystallization tank and mixing it with the raw oil in a certain proportion, the oil with poor low-temperature flow characteristics after crystallization can be diluted, which can further ensure the fluidity of the raw oil during transportation.

[0040] (4) The cooling water of the membrane filter press is controlled by self-circulation through the squeeze water tank, which is simple and easy to implement. The water temperature is precisely controlled, avoiding uneven crystallization caused by poor distribution of cold air in the large freezer.

[0041] (5) The membrane filter press integrates crystallization, filtration and extrusion, with automated crystallization control program, more uniform crystallization control, short operating cycle, high efficiency and significant energy saving. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of a dry fractionation system for a high solids index oil.

[0043] Figure 2 This is a schematic diagram of the pre-crystallization zone.

[0044] Figure 3 This is a schematic diagram of a chilled water circulation system.

[0045] Figure 4 This is a connection diagram of the membrane filter press, squeeze tank, and purge tank in the solid-liquid separation zone.

[0046] Figure 5 This is a connection diagram of the liquid oil tank and cleaning oil tank in the solid-liquid separation zone.

[0047] Figure 6 This is a connection diagram of the stearin tank and hot water tank in the solid-liquid separation zone.

[0048] In the diagram, 001 is the pre-crystallization zone, 002 is the chilled water circulation equipment zone, and 003 is the solid-liquid separation zone.

[0049] FT1 is the raw material tank, FT2 is the pre-crystallization tank, FT12 is the hot water tank, FT5 is the stearin tank, FT11 is the squeeze water tank, FT6 is the liquid oil tank, FT4 is the cleaning oil tank, FT15 is the gas-liquid separator, FT10 is the purge tank, FT8 is the chilled water return tank, FT9 is the chilled water tank, CT1 is the cooling tower, and 0031 is the membrane filter press.

[0050] PHE1 is the first heat exchanger, PHE2 is the second heat exchanger, PHE3 is the third heat exchanger, and PHE4 is the fourth heat exchanger.

[0051] PF is the transfer pump, LL is the level monitor, TIC is the temperature indicator controller, PGD is the differential pressure gauge, PG is the pressure gauge, TT is the temperature transmitter, PT is the pressure transmitter, PS is the pressure switch, TI is the temperature indicator, PTI is the pressure indicator transmitter, LS is the level switch, LC is the level controller, and SG is the sight glass. Detailed Implementation

[0052] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0053] Example 1

[0054] A dry fractionation process for high solids index oils includes the following steps:

[0055] a. The raw oil at temperature T1 enters the pre-crystallization tank for pre-crystallization at temperature T2.

[0056] b. The pre-crystallized feed oil is fed into the membrane filter press. After the filling is completed, the feed oil in the membrane filter press is cooled until the feed oil is cooled to the final temperature T3.

[0057] c. Start the extrusion system of the membrane filter press to extrude the raw oil to obtain fractionated oil and stearin. After extrusion, purge the filter chamber.

[0058] Among them, the value range of T1 is 40-50℃, the value range of T2 is 10-35℃, and the value range of T3 is 10-25℃.

[0059] As a preferred option, the feedstock oil is palm kernel oil, palm kernel stearin obtained from secondary fractionation, shea butter oil, or intermediate fractionation product of palm oil. The fractionated liquid oil and stearin can be named as follows: palm kernel stearin, palm kernel stearin, shea butter stearin, soft palm oil, or super palm oil.

[0060] As a preferred option, the fractionated oil obtained in step c, or the fractionated oil obtained in step c mixed with the feed oil, is transported to a pre-crystallization tank, and steps a, b, and c are repeated to obtain secondary fractionated oil and stearin.

[0061] As a preferred option, the value of T2 is in the range of 21-27℃, and the value of T3 is in the range of 17-21℃;

[0062] When the feedstock oil is palm kernel oil, the value of T2 is in the range of 21-25℃, and the value of T3 is in the range of 18-21℃. The specific selection of T1, T2, and T3 can be determined according to the quality of the feedstock and product requirements.

[0063] As a preferred option, in step c, the terminal extrusion pressure of the membrane filter press is 6-28 bar; when the raw material oil is palm kernel oil, the terminal extrusion pressure is selected as 16-20 bar.

[0064] The selection of membrane filter presses includes, but is not limited to, 30 bar. It encompasses currently available 6-30 bar filter presses, and even future filter presses exceeding 30 bar. For dry fractionation of palm kernel oil or shea butter, a 30 bar membrane filter press is currently the preferred choice. For palm kernel oil fractionation, 16-24 bar is preferred, with 16-20 bar being the optimal choice.

[0065] As a preferred option, in step b, chilled water is used to cool the pressure medium of the membrane filter press. The cooled pressure medium then enters the extrusion chamber of the membrane filter press and is discharged, thereby cooling the raw oil in the filter chamber. The chilled water used to cool the pressure medium and the chilled water used to cool the pre-crystallization tank can be supplied by the same pump, or by two separate pumps, with the water volume adjusted by frequency converter control.

[0066] As a preferred option, the separated fractionated oil is returned to the pre-crystallization tank, and the solid content after pre-crystallization is controlled to be 20% to 50%.

[0067] As a preferred option, in step b, the filling process is determined by the appearance of liquid oil at the liquid oil outlet of the membrane filter press. When the filter chamber is determined to be full, the filling process ends. During the filling process, the liquid oil flowing out of the liquid oil outlet of the membrane filter press is returned to the pre-crystallization tank in step a.

[0068] After filling is completed, purge the oil inlet pipe of the membrane filter press to purge the oil into the purge tank;

[0069] In step c, after the extrusion is completed, the filter chamber of the membrane filter press is purged, and the oil is purged into the purging tank.

[0070] As a preferred embodiment, after the filter chamber is purged in step c, the membrane filter press is opened, and the separated stearin falls into the stearin tank below the filter chamber of the membrane filter press.

[0071] The stearin bath is heated with hot water or steam, and the temperature of the molten stearin in the bath is controlled at 40-50℃. The melted stearin is then transferred to a stearin container. The melting temperature can also be adjusted within the range of 40-80℃, preferably 40-60℃, and optimally 40-50℃.

[0072] A dry fractionation system for high solids index oils is divided into three zones: a pre-crystallization zone, a chilled water circulation zone, and a solid-liquid separation zone, such as... Figures 1-6 As shown, the system specifically includes,

[0073] Raw material tanks are used to store raw oil.

[0074] The first heat exchanger is connected to the raw material tank via a fluid conveying device to pre-cool the raw material oil output from the raw material tank;

[0075] The pre-crystallization tank is connected to the first heat exchanger via a fluid conveying device to cool and crystallize the raw oil output from the first heat exchanger;

[0076] A membrane filter press is connected to a pre-crystallization tank via a fluid conveying device to squeeze the pre-crystallized raw oil to achieve solid-liquid separation.

[0077] The liquid oil tank is connected to the membrane filter press via fluid conveying equipment and is used to store the separated extract liquid oil.

[0078] Stearin tank, connected to a membrane filter press, is used to hold the separated stearin;

[0079] A hot water tank, connected to a stearin tank via a hot water pipe, is used to heat the stearin inside the tank.

[0080] The squeeze tank, connected to the squeeze chamber of the membrane filter press, is used to provide pressure medium to the membrane filter press and to cool the filter chamber through the cooled pressure medium;

[0081] Purge tank, used to store the liquid oil purged out;

[0082] Chilled water circulation equipment is used to provide chilled water to the system, including chilled water return tanks, chilled water tanks, cooling towers, etc.

[0083] Other auxiliary instruments and equipment, such as gas-liquid separators, level monitors, temperature indicators and controllers, differential pressure gauges, pressure gauges, temperature transmitters, pressure transmitters, pressure switches, temperature indicators, pressure indicators and transmitters, level switches, level controllers, sight glasses, etc.

[0084] The raw oil in the raw material tank enters the pre-crystallization tank after passing through the first heat exchanger. Then it is transported to the membrane filter press through the fluid conveying equipment. After filling, the filter chamber is cooled by the pressure medium in the squeeze water tank, so that the raw oil in the filter chamber is further crystallized. Then the squeezing program of the membrane filter press is started to separate stearin and fractionated oil.

[0085] The fluid transport equipment includes pipelines and a transport pump. The cleaning oil tank and the liquid oil tank are equipped with a second heat exchanger and a third heat exchanger, respectively. The extrusion water tank is equipped with a fourth heat exchanger, which cools the extrusion medium (water in this embodiment) in the extrusion water tank through heat exchange with chilled water.

[0086] like Figure 4 As shown, the squeeze tank has an inlet and an outlet. The inlet is connected to the squeeze chamber of the membrane filter press via a discharge pipe, and a valve is installed on the discharge pipe. The outlet is connected to the squeeze chamber of the membrane filter press via a squeeze pipe. The cooled squeeze medium enters the squeeze chamber through the squeeze pipe and then flows back to the squeeze tank through the discharge pipe. The temperature of the squeeze medium is controlled by heat exchange with chilled water in the fourth heat exchanger, achieving self-circulation control of the cooling water. A delivery pump capable of generating high-pressure fluid is installed on the squeeze pipe.

[0087] Using the above-mentioned process and system, RBD-PKO and RBO-PKO are fractionated as follows:

[0088] 1. RBD-PKO (refined bleached and deodorized palm kernel oil, SFI: 39 at 20°C) at 40°C was fed into a pre-crystallization tank equipped with cooling fins. Cooling water was injected into the cooling fins under programmed control, and the oil was cooled to 24-25°C with stirring. The palm kernel oil in the pre-crystallization tank was then transferred to a 30 bar g membrane filter press with a chamber thickness of 15 mm. A chilled water circulation system was activated to cool and crystallize the palm kernel oil within the 30 bar filter press chamber. The cooling water temperature was controlled via a self-circulating cooling water system in the compression water tank. The final temperature in the filter chamber was controlled at 21°C. After 4 hours of cooling, the slurry was pressed for over 30 minutes under progressively increasing pressure using the 30 bar membrane filter press's built-in compression program to separate the solids from the liquid phase. The IV values ​​of palm kernel stearin (PKS) and refined palm kernel extract (PKL) were then analyzed. The results showed IV values ​​of 7.4 and 22.7, respectively.

[0089] 2. Refined palm kernel oil (RBO-PKO) heated to 40°C and refined palm kernel extract (PKL) were mixed in a 1:1 weight ratio and then fed into a pre-crystallization tank equipped with cooling fins. Cooling water was injected into the cooling fins under programmed control, and the mixture was cooled to 24-25°C with stirring. The palm kernel oil in the pre-crystallization tank was then transferred to a 30 bar membrane filter press with a chamber thickness of 15 mm. A chilled water circulation system was activated to cool and crystallize the palm kernel oil in the 30 bar membrane filter press chamber. The cooling water temperature was controlled by a self-circulating cooling water system in the extrusion water tank. After 4 hours of cooling, the slurry was extruded for over 60 minutes under progressively increasing pressure using the built-in extrusion program of the 30 bar membrane filter press to separate the solids from the liquid phase. The IV values ​​of the separated palm kernel stearin (PKS) and refined palm kernel extract (PKL) were then analyzed. The results showed IV values ​​of 6.55 and 25.1, respectively.

[0090] The above embodiments are preferred embodiments of the invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A dry fractionation process for high solids index oils, characterized in that: Includes the following steps, a. The raw oil at temperature T1 enters the pre-crystallization tank for pre-crystallization at temperature T2. b. The pre-crystallized feed oil is fed into the membrane filter press. After the filling is completed, the feed oil in the membrane filter press is cooled until the feed oil is cooled to the final temperature T3. c. Start the extrusion system of the membrane filter press to extrude the raw oil to obtain fractionated oil and stearin. After extrusion, purge the filter chamber. Among them, the value range of T1 is 40-50℃, the value range of T2 is 10-35℃, and the value range of T3 is 10-25℃.

2. The dry fractionation process for high solids index oils according to claim 1, characterized in that: The feedstock oil is palm kernel oil, palm kernel liquid oil obtained from secondary fractionation, shea butter, or intermediate fractionation product of palm oil.

3. The dry fractionation process for high solids index oils according to claim 1, characterized in that: The fractionated oil obtained in step c, or the fractionated oil obtained in step c mixed with the feed oil, is then transported to a pre-crystallization tank, and steps a, b, and c are repeated to obtain secondary fractionated oil and stearin.

4. The dry fractionation process for high solids index oils according to claim 1, characterized in that: The value range of T2 is 21-27℃, and the value range of T3 is 17-21℃; When the raw material oil is palm kernel oil, the value range of T2 is 21-25℃, and the value range of T3 is 18-21℃.

5. The dry fractionation process for high solids index oils according to claim 1, characterized in that: In step c, the terminal extrusion pressure of the membrane filter press is 6-28 bar; when the feed oil is palm kernel oil, the terminal extrusion pressure is selected as 16-20 bar.

6. The dry fractionation process for high solids index oils according to claim 1, characterized in that: In step b, chilled water is used to cool the pressure medium of the membrane filter press. The cooled pressure medium enters the extrusion chamber of the membrane filter press and is then discharged, thereby cooling the raw oil in the filter chamber.

7. The dry fractionation process for high solids index oils according to claim 1, characterized in that: The separated extract oil is returned to the pre-crystallization tank, and the solid content after pre-crystallization is controlled to be 20% to 50%.

8. The dry fractionation process for high solids index oils according to claim 1, characterized in that: In step b, the filter chamber is filled by observing the liquid oil at the liquid oil outlet of the membrane filter press. When the filter chamber is filled, the filling process ends. During the filling process, the liquid oil flowing out of the liquid oil outlet of the membrane filter press is returned to the pre-crystallization tank in step a. After filling is completed, purge the oil inlet pipe of the membrane filter press to purge the oil into the purge tank; In step c, after the extrusion is completed, the filter chamber of the membrane filter press is purged, and the oil is purged into the purging tank.

9. The dry fractionation process for high solids index oils according to claim 1, characterized in that: After the filter chamber is purged in step c, the membrane filter press is opened, and the separated stearin falls into the stearin tank below the filter chamber of the membrane filter press. Hot water or steam is used to heat the stearin bath, and the temperature of the molten oil in the stearin bath is controlled at 40-50℃. The melted stearin is then transferred to the stearin container.

10. A dry fractionation system for high solids index oils, characterized in that: include, Raw material tanks are used to store raw oil. The first heat exchanger is connected to the raw material tank via a fluid conveying device to pre-cool the raw material oil output from the raw material tank; The pre-crystallization tank is connected to the first heat exchanger via a fluid conveying device to cool and crystallize the raw oil output from the first heat exchanger. A membrane filter press is connected to a pre-crystallization tank via a fluid conveying device to squeeze the pre-crystallized raw oil to achieve solid-liquid separation. The liquid oil tank is connected to the membrane filter press via fluid conveying equipment and is used to store the separated extract liquid oil. Stearin tank, connected to a membrane filter press, is used to hold the separated stearin; A hot water tank, connected to a stearin tank via a hot water pipe, is used to heat the stearin inside the tank. The squeeze tank, connected to the squeeze chamber of the membrane filter press, is used to provide pressure medium to the membrane filter press and to cool the filter chamber through the cooled pressure medium; Purge tank, used to store the liquid oil purged out; Chilled water circulation equipment is used to supply chilled water to the system; The raw oil in the raw material tank enters the pre-crystallization tank after passing through the first heat exchanger. Then it is transported to the membrane filter press through the fluid conveying equipment. After filling, the filter chamber is cooled by the pressure medium in the squeeze water tank, so that the raw oil in the filter chamber is further crystallized. Then the squeezing program of the membrane filter press is started to separate stearin and fractionated oil.

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