Fournisseurs de raffineries d'huile alimentaire — Neutralisation, Blanchiment & Désodorisation

An edible oil refinery plant converts crude vegetable oil (from extraction) or crude imported oil (purchased as a refinery feedstock) into food-grade refined, bleached, and deodorised (RBD) oil suitable for consumer and food manufacturing use. The refinery removes four categories of impurities from crude oil: free fatty acids (FFA), phospholipids, colour bodies (carotenoids and chlorophylls), and volatile off-odour compounds.

The three core stages of edible oil refining:

Stage 1: Degumming and neutralisation / FFA removal Crude oil is treated to remove phospholipids (gums) and free fatty acids. Two principal routes:

• Chemical (alkali) refining: Crude oil is mixed with dilute caustic soda (NaOH) solution that reacts with FFA to form soap (saponification). The soap is removed by centrifuge, and the oil is water-washed. This process also removes most phospholipids simultaneously. Suited for crude oils with moderate FFA (1–5%).
• Physical refining: Degummed crude oil is refined using high-vacuum steam distillation in the deodoriser — the FFA are removed along with volatile odour compounds in a single combined step. This process requires thorough pre-degumming of the crude oil but produces higher oil yield and no wastewater from soap making. Used extensively for palm oil refining and increasingly for other vegetable oils with effective pre-degumming.

Stage 2: Bleaching The neutralised (or degummed crude in physical refining) oil is mixed with activated bleaching earth (fuller's earth/acid-activated clay) under vacuum and heat. The bleaching earth adsorbs remaining colour bodies (carotenes, chlorophylls), residual soap traces, trace metals, and phospholipid traces. After a contact time, the oil-earth mixture is filtered through a pressure leaf filter or plate-and-frame filter press to remove the spent earth. The result is a pale, clarified oil ready for deodorisation.

Stage 3: Deodorisation The bleached oil is heated to 220–265°C under high vacuum (typically 2–5 mbar absolute) with direct steam injection. The steam strips volatile odour compounds (aldehydes, ketones, lower fatty acids) and removes residual FFA (in physical refining), tocopherols degradation products, and pesticide traces. The deodoriser is the most capital-intensive and technically demanding piece of refinery equipment — quality and operational efficiency of the deodoriser directly determines the quality of the finished refined oil. Packed column deodorisers (continuous) and tray deodorisers (semi-continuous) are the two principal designs.

Fractionation (additional stage for palm oil, coconut oil, PKO): After deodorisation, palm oil and lauric oils are crystallised under controlled cooling in crystallisation tanks, then filtered through membrane filter presses to separate olein (liquid fraction) from stearin (solid fraction).

Edible oil refinery plants are categorised by their operational mode — batch, semi-continuous, or fully continuous — which roughly corresponds to capacity range and capital cost level:

Batch refinery (1–30 TPD throughput): Each refining step (neutralisation, bleaching, deodorisation) is performed in a single vessel for one batch of oil at a time, with manual or semi-automated transfer between stages. Simple to operate and maintain; lower capital cost than continuous systems; flexible for processing multiple oil types with cleaning between runs. Suitable for small and medium-scale operations. Batch deodoriser technology is mature and reliable at this scale.

Semi-continuous refinery (20–100 TPD): Neutralisation and bleaching are operated batch-wise; deodorisation is operated semi-continuously (multiple trays process different batches simultaneously). Better energy efficiency than batch, more complex automation. The most common configuration for mid-scale oil refineries in developing markets.

Fully continuous refinery (100+ TPD): All stages operate continuously with automated control. Requires sophisticated instrumentation and process control. Maximum energy efficiency and product consistency. Economically justified at 100+ TPD throughput. Supplied by specialist plant engineers (De Smet, Crown, Alfa Laval) as complete turnkey systems.

Key specifications when purchasing a refinery plant:

• Input crude oil type and quality specification (FFA%, phospholipid content, colour)
• Target finished oil specification (FFA, colour, peroxide value, odour)
• Throughput capacity (TPD of crude oil input)
• Utilities available at site (steam pressure, cooling water, electricity supply)
• Compliance requirements (EU food safety, local environmental regulations for effluent and spent earth disposal)
• Turnkey (full design + supply + installation + commissioning) vs equipment-only supply

Cost indication: A small batch refinery plant at 5 TPD capacity costs approximately USD 40,000–150,000 for Chinese-supplied equipment; 20 TPD semi-continuous: USD 200,000–600,000; 100 TPD continuous: USD 1,500,000–5,000,000+ depending on scope and origin.