CN-121975571-A - Oil squeezing method and system based on microwave pretreatment-mechanical characteristic linkage

CN121975571ACN 121975571 ACN121975571 ACN 121975571ACN-121975571-A

Abstract

The invention relates to an oil squeezing method and system based on microwave pretreatment-mechanical characteristic linkage, wherein the method comprises the following steps of S1, selecting an oil seed raw material with uniform particle size and no mildew, adjusting the water content of the oil seed raw material, S2, sending the oil seed raw material into a microwave pretreatment device for heating to reach a preset temperature range, recording microwave pretreatment parameters, S3, carrying out cooling treatment on the oil seed raw material, S4, carrying out online or quasi-online mechanical characteristic detection on the oil seed raw material, S5, determining a target mechanical characteristic range according to a pre-established matching relation under a preset fixed squeezing condition, comparing the mechanical characteristic index with the target mechanical characteristic range, S6, carrying out mechanical squeezing on the oil seed raw material judged to be suitable for being squeezed under the fixed squeezing condition to obtain crude oil and cake, S7, measuring the oil yield index through sampling, and evaluating the microwave parameter adjusting effect. The invention obviously improves the oil yield, reduces the cake residual oil rate and unit energy consumption, and improves the grease quality.

Inventors

ZHENG CHANG
HUANG YING
ZHOU QI
LI WENLIN
HUANG FENGHONG
WAN CHUJUN
LIU CHANGSHENG
TANG XIANGNING

Assignees

中国农业科学院油料作物研究所

Dates

Publication Date: 20260505
Application Date: 20260130

Claims (10)

1. The oil squeezing method based on microwave pretreatment-mechanical property linkage is characterized by comprising the following steps of: S1, cleaning, impurity removing and crushing treatment are carried out on oil seed raw materials, oil seed raw materials with uniform particle size and no mildew are selected, and the water content of the oil seed raw materials is adjusted through tempering operation; S2, sending the tempered oil seed raw material into a microwave pretreatment device, carrying out microwave heating under the set microwave frequency, power and treatment time conditions, enabling the oil seed raw material to reach a preset temperature range, and recording microwave pretreatment parameters; s3, cooling the oil seed raw material subjected to microwave pretreatment, and reducing the temperature of the oil seed raw material to a temperature range in which degradation of oil quality caused by high temperature is avoided; s4, carrying out on-line or quasi-on-line mechanical property detection on the oil seed raw material subjected to microwave pretreatment and cooling to obtain mechanical property indexes; S5, under the preset fixed squeezing condition, determining a target mechanical property range according to a pre-established matching relation, and comparing the mechanical property index with the target mechanical property range; when the mechanical property index deviates from the target mechanical property range, automatically correcting microwave pretreatment parameters of the oil materials in the subsequent batch according to the deviation direction and the deviation degree; S6, mechanically squeezing the oilseed raw material which is judged to be suitable for being squeezed under the fixed squeezing condition in the step S5 to obtain crude oil and cake; S7, measuring oil yield indexes through sampling, evaluating microwave parameter adjustment effects, and if systematic deviation occurs in the oil yield effects in the long-term operation process, carrying out small-scale correction on the target mechanical characteristic range, and updating the matching model.
2. The oil pressing method based on microwave pretreatment-mechanical property linkage according to claim 1, wherein in the step S1, the moisture content of the oil seed raw material regulated by the tempering operation is 7% -13%.
3. The oil squeezing method based on the linkage of microwave pretreatment and mechanical properties according to claim 1, wherein in the step S2, a microwave pretreatment device is a tunnel type microwave oven, the microwave frequency is 915-MHz or 2450-MHz, the microwave power is 400-1200W, or the corresponding power density is 0.3-1.2W/g, the thickness of the oil layer is less than or equal to 5-cm, the treatment time is 2-8 min, and the temperature of the oil seed raw material reaches a preset range of 80-150 ℃.
4. The oil squeezing method based on microwave pretreatment-mechanical characteristic linkage according to claim 1, wherein in the step S3, a cooling treatment method is adopted, the cooling air temperature is-20 ℃ to 10 ℃, the cooling air speed is 5 m/S to 25 m/S, the cooling rate is not lower than 1.5 ℃ per second, and the temperature of the oil seed raw material is reduced to 35 ℃ to 50 ℃.
5. The oil squeezing method based on microwave pretreatment-mechanical property linkage according to claim 1, wherein in the step S4, the oil seed raw material subjected to microwave pretreatment and cooling is sent to a mechanical property detection device, a uniaxial compression and/or stress-relaxation test mode is adopted, the test speed is 40-60 mm/min, the deformation compression rate is 20% -50%, a force-displacement or stress-strain curve is obtained, and at least one mechanical property index is extracted, wherein the mechanical property index comprises hardness, fracture force and plasticity parameters.
6. The oil press method based on microwave pretreatment-mechanical property linkage according to claim 1, wherein in the step S5, the preset fixed press conditions include a fixed screw press structure, a fixed screw rotation speed, and a fixed press chamber temperature and/or back pressure, and the target mechanical property ranges from hardness and breaking force reduced by 10% -30% compared with the non-microwave treated oil.
7. The method for oil squeezing based on microwave pretreatment-mechanical property linkage according to claim 6, wherein in the step S5, the mechanical property index measured in the step S4 is compared with the target mechanical property range, if the mechanical property index of the current batch of oil seed raw materials is within the target mechanical property range, it is determined that the batch of oil seed raw materials is in a suitable squeezing state, the current microwave pretreatment parameters can be continuously adopted, and if the index of hardness, cracking force or plasticity is higher than or deviates from the target mechanical property range, the microwave power, processing time and/or target temperature of the subsequent batch of oil materials are automatically adjusted by the control system according to the deviation direction, so that the mechanical property of the subsequent batch gradually converges to the target mechanical property range.
8. The oil squeezing method based on microwave pretreatment-mechanical characteristic linkage according to claim 7, wherein in the step S5, the matching relationship is established by testing the mechanical characteristic index, oil yield, cake residual oil rate and unit energy consumption of the oil under different microwave pretreatment parameter combinations under a fixed squeezing condition and utilizing multiple regression or response surface analysis.
9. The oil pressing method based on microwave pretreatment-mechanical property linkage according to claim 1, wherein the oil raw material is one or more of rapeseeds, peanuts, soybeans, sesame, safflower seeds, linseed and sunflower seeds.
10. An oil press system based on microwave pretreatment-mechanical property linkage, comprising: the carefully chosen module is used for cleaning the oil and adjusting the water content; the microwave pretreatment module is used for carrying out microwave heating on the oil under the set frequency, power and time; the cooling module is used for cooling the oil after the microwave pretreatment; The mechanical property detection module is used for obtaining mechanical property indexes of oil hardness, cracking force, elasticity and plasticity; The fixed parameter screw press module is used for mechanically pressing the oil under fixed press conditions; And the control module is used for automatically adjusting the microwave power, the processing time and/or the target temperature of the microwave pretreatment module according to the comparison result of the mechanical property index and the target mechanical property range.

Description

Oil squeezing method and system based on microwave pretreatment-mechanical characteristic linkage Technical Field The invention relates to the technical field of vegetable oil processing, in particular to an oil squeezing method and system based on microwave pretreatment-mechanical characteristic linkage. Background The mechanical pressing method is one of the main technologies of oil extraction, has the advantages of simple process, low cost, capability of better retaining the original flavor of oil and the like, and is widely applied to the processing process of various oil materials such as rapeseeds, peanuts, soybeans and the like. Microwave pretreatment has proven to be a technique for improving the oil yield and quality of oil press efficiently, which vaporizes water in cells by internal heating effect, damages cell wall structure, and thereby reduces mechanical strength of oil and increases porosity. The microwave pretreatment can quickly change the moisture migration and cell structure in the oil material through the action of an electromagnetic field, and has remarkable influence on the mechanical properties of the oil material such as hardness, rupture force, elasticity and the like, thereby influencing the precipitation behavior of the oil material in the pressing process. When the plasticity of the oil is low, the structure of the pressed cake body is loose, an effective grease permeation channel is difficult to form, and the residual oil rate is high, otherwise, if the plasticity is too high, excessive extrusion of the material is easy to cause, the cake body is lost along with the grease, and the sustainability and the oil yield of the pressing process are seriously affected. Therefore, developing a high-efficiency mechanical squeezing oil-producing method capable of guiding by precisely regulating and controlling the mechanical properties of oil becomes a technical problem to be solved urgently in the current oil processing field. However, the existing microwave pretreatment process depends on fixed power and time, cannot adapt to oil materials with different varieties, water content and particle size, and is easy to cause insufficient treatment or overheating, and the quality and energy consumption of the oil materials are affected. The mechanical properties (such as hardness, elasticity, breaking energy and the like) of the oil materials after microwave treatment and the oil yield are not established, so that the pressing energy consumption is difficult to optimize. Research shows that when the hardness of oil is higher, more power is consumed in the squeezing process, and the squeezing chamber is easy to wear. In the prior art, the microwave pretreatment relies on experience, the squeezing condition is basically fixed, and the oil mechanical property lacks quantification and regulation. Disclosure of Invention The technical problem to be solved by the invention is to provide the oil squeezing method and the system based on microwave pretreatment-mechanical characteristic linkage, which can obviously improve the oil yield, reduce the cake residual oil rate and unit energy consumption and improve the quality of grease. The technical scheme adopted for solving the technical problems is that the oil squeezing method based on microwave pretreatment-mechanical characteristic linkage comprises the following steps: S1, cleaning, impurity removing and crushing treatment are carried out on oil seed raw materials, oil seed raw materials with uniform particle size and no mildew are selected, and the water content of the oil seed raw materials is adjusted through tempering operation; S2, sending the tempered oil seed raw material into a microwave pretreatment device, carrying out microwave heating under the set microwave frequency, power and treatment time conditions, enabling the oil seed raw material to reach a preset temperature range, and recording microwave pretreatment parameters; s3, cooling the oil seed raw material subjected to microwave pretreatment, and reducing the temperature of the oil seed raw material to a temperature range in which degradation of oil quality caused by high temperature is avoided; s4, carrying out on-line or quasi-on-line mechanical property detection on the oil seed raw material subjected to microwave pretreatment and cooling to obtain at least one mechanical property index; S5, under the preset fixed squeezing condition, determining a target mechanical property range according to a pre-established matching relation, and comparing the mechanical property index with the target mechanical property range; when the mechanical property index deviates from the target mechanical property range, automatically correcting at least one of microwave pretreatment parameters of the oil in the subsequent batch according to the deviation direction and the deviation degree; S6, mechanically squeezing the oilseed raw material which is judged to be suitable for being squeezed under the f