Project Background
A comprehensive grain & oil refinery with 120,000 tons annual edible soybean oil output uses activated clay to adsorb pigments, colloids and micro impurities in crude oil during de-coloring. Traditional plate-and-frame filter presses with 120m³/h flow separate oil and saturated clay residue, yet structural defects restrict production capacity: open design triggers secondary oil pollution, manual slag removal wastes production time, and high residual oil in filter cakes raises operation costs. To expand daily refining capacity, the client required fully enclosed, automatic online slag discharge precision filters without disposable consumables for continuous production, lower oil loss, less labor and clearer finished oil.
Core Pain Points
Filter cloth clogs every 6 hours, requiring full-line shutdown for 4-hour slag removal & cloth replacement, halting production and causing oxidized waste oil.
Two-shift manual operation with heavy labor; disposable filter cloth costs 170,000 RMB annually.
Open structure allows dust contamination; oil transmittance below 90% leads to dealer returns and brand losses.
Filter cake residual oil rate reaches 12%, wasting finished soybean oil and boosting unit production costs.
No automatic differential pressure monitoring; fully clogged cloth causes sharp pressure spikes, risking hot oil leakage and safety hazards.
Customized LEFILTER Solution
3 sets of LF-PZ precision slag discharge filters are arranged in parallel for high-temperature viscous edible oil. 304 food-grade stainless steel for the tank complies with food hygiene standards without heavy metal precipitation. The core 200μm sintered stainless steel screen matches a built-in 360° rotary scraper self-cleaning mechanism. When differential pressure hits 0.13MPa, the scraper peels filter cakes and the bottom pneumatic sealed slag valve opens for 30-second slag discharge without oil supply interruption. Sanitary explosion-proof PLC records daily slag discharge frequency and pressure curves, uploading data to central control for remote parameter adjustment. Standard quick-fit flanges connect original pipelines without reconstruction. Full equipment delivered within 9 days.
Operating Effects
Stable operation for 13 months with 98% solid impurity interception. Filter cake residual oil dropped from 12% to 4.8%, saving 690,000 RMB annual raw material costs. Automatic sealed slag discharge cuts operators from 2 to 1, saving 320,000 RMB annual labor & cloth costs. Fully enclosed structure lifts oil transmittance above 95% with zero return orders. Reusable metal screens eliminate disposable filter cloth; service life exceeds 10 years. This filter solves four major drawbacks of plate-and-frame presses and becomes a demonstration grain & oil de-coloring filtration project.
