Can One Oil Mill Plant Process Different Oilseeds?
Many investors planning to build an oil mill plant ask the same question:
Can one oil processing production line produce different types of edible oils?
The answer is yes, but it’s not an overnight process. Modern oil press systems and edible oil processing plants are capable of handling a wide variety of oil-bearing raw materials. However, each raw material has unique physical and chemical properties, which means that pretreatment processes and operating parameters must be adjusted accordingly—and sometimes specific equipment is required. A well-designed oil processing production line offers excellent flexibility while ensuring consistent oil yield, product quality, and operational efficiency.
Common Oilseeds Used in an Oil Mill Plant
The foundation of efficient oil processing lies in understanding the unique characteristics of different oilseeds. The oil content of oil-bearing raw materials varies greatly, ranging from 15% to over 60%, which fundamentally determines the appropriate extraction method.
High-Oil-Content Raw Materials (30%–60%)
High-oil oilseeds require special handling to prevent issues such as oil buildup in the oil chambers and oil adhesion to screw components. Common high-oil-content raw materials include:
- Sunflower seeds: 40–55% oil content
- Peanuts/Groundnuts: 45–55% oil content
- Rapeseed/Canola: 40–48% oil content
- Sesame seeds: 45–55% oil content
- Palm kernels: 45–50% oil content
- Corn germ: 45–50% oil content
For high-oil-content raw materials, insufficient heating can easily cause the pressing chamber to clog; improper temperature control may lead to overheating and oil degradation. These raw materials typically require pre-pressing followed by solvent extraction to maximize oil recovery while maintaining the quality of the cake.
Raw materials with relatively high oil content generally follow the following processing flow:
Cleaning → Dehulling (if necessary) → Crushing → Flaking → Cooking/Conditioning → Pre-pressing → Solvent Extraction → Oil Refining
This process improves overall oil yield while reducing residual oil in the meal.
Low-oil-content raw materials (below 30%)
- Soybeans: 18–22% oil content
- Rice bran: 15–20% oil content
- Cottonseed: 18–25% oil content
These raw materials are typically processed using direct solvent extraction after appropriate pretreatment, or through a combination of mechanical pressing and solvent extraction. Since these seeds are rich in fiber or protein, high-performance equipment is required to handle the high pressing resistance and prevent excessive wear on the machinery.
For low-oil-content crops, the recommended processing flow is typically:
Cleaning → Conditioning → Flaking → Solvent Extraction → Oil Refining
Since mechanical pressing alone cannot efficiently recover oil from low-oil materials, extraction technology is generally preferred.
Why Different Oilseeds Require Different Pretreatments
Although the downstream refining process is highly standardized, the pretreatment stage varies significantly depending on the raw material.
1. Differences in Hardness
Hard raw materials, such as palm kernels, require more powerful crushers.
Soft raw materials, such as soybeans, require gentle crushing to avoid generating excessive fine powder.
2. Differences in Moisture Content
Some oilseeds need to be dried before processing, while others require moisture adjustment during the cooking process.
Inappropriate moisture content can significantly reduce oil yield.
3. Different Shell Structures
Certain oilseeds require dehusking before pressing, including cotton seeds, sunflower seeds, peanuts, and walnuts. Dehusking can improve oil yield, reduce fiber content, and lower energy consumption.
4. Different Protein Characteristics
Soybean processing typically focuses on preserving protein quality to produce soybean meal, which requires strict temperature control.
Is the Refining Process Universal?
Unlike pretreatment, the oil refinery plant is highly versatile. Once crude oil is extracted, most edible oils can be processed using the same refining equipment. With only minor process adjustments required for different oilseeds, a single refining line can process crude oil from a variety of sources. This makes the refining section one of the most flexible parts of a modern oil processing production line.
Huatai Customized Oil Mill Solutions
If you plan to process two to three different oilseeds on the same production line, Huatai can design a customized solution based on your production needs.
Our engineers will develop dedicated pretreatment processes for each raw material while ensuring that the oil press, extraction system, and refining equipment are as versatile as possible. This optimized design reduces capital investment, shortens changeover time, and maintains high oil extraction efficiency. Whether you are planning to build a small oil mill plant, a medium-sized oil processing production line, or a complete turnkey edible oil factory, Huatai can provide professional engineering support, equipment manufacturing, installation and commissioning, operator training, and after-sales technical services.
Contact us today to receive an oil mill plant design tailored to your raw materials and production capacity, along with equipment quotes and professional consulting services.