You’re not alone if you’ve seen your mid-sized screw press produce inconsistent oil yields or struggle with frequent clogs. The real bottleneck isn’t always the press itself—it’s often what happens before the oil hits the screw.
In fact, studies show that up to 15–20% of total oil loss in small- to medium-scale plants can be traced back to suboptimal pre-treatment processes. That means for every 100 tons of raw material processed, you could be losing 15–20 tons of potential yield—simply because of poor cleaning, incorrect particle size, or uncalibrated steaming parameters.
| Process Step | Ideal Parameters | Common Mistakes |
|---|---|---|
| Raw Material Cleaning | Remove dust, stones, and moisture (max 8%) | Skipping magnetic separators or air classifiers |
| Crushing & Sieving | Particle size: 1–2 mm for sesame; 2–4 mm for sunflower | Over-crushing leads to sticky paste, under-crushing causes poor flow |
| Steaming (Cooking) | Temperature: 85–95°C | Time: 15–25 min | Moisture: 7–10% | Inconsistent heat transfer = uneven gelatinization |
Here’s where many operators miss the mark: treating all oilseeds the same. For example, sesame seeds require gentler handling due to their high oil content and fragile structure—over-processing results in oily sludge and low fiber recovery. Meanwhile, sunflower seeds benefit from slightly larger particles to maintain airflow during pressing and reduce internal friction.
“When we standardized our pre-treatment SOPs based on seed type, our oil yield jumped by 8% within one month—and our waste oil residue dropped from 12% to just 6%.”
— Ahmed R., Plant Manager, Egypt
If you're experiencing issues like excessive oil in the cake or recurring blockages in the feed section, it might not be a mechanical failure—it could be a data gap. Start logging key metrics daily: moisture levels, temperature spikes, particle uniformity, and even ambient humidity. This builds a foundation for continuous improvement—not just quick fixes.
And don’t underestimate the power of visual checks. A well-trained operator who knows what to look for—like a sudden drop in throughput or an unusual odor during steaming—can catch problems before they escalate into costly downtime.
You've got the equipment. Now make sure the process behind it is as sharp as your competitive edge.