Peanut Oil Refining Process | Your Complete Guide

Introduction

Peanut oil refining transforms crude oil obtained from pressing or extraction into clear, odorless, and safe edible oil. Each step requires specific equipment. Manufacturers offer three types of refining equipment based on production scale: batch, semi-continuous, and fully continuous systems.

Below, I will explain the complete peanut oil refining process, describe the equipment for each step, analyze investment costs for refining plants, and show Huatai Group's refining equipment advantages. I hope this information will help you better plan your peanut oil refining project.

4 Steps Peanut Oil Refining Process

The peanut oil refining process consists of four core stages: degumming, deacidification, decolorization, and deodorization. Each step is crucial and determines the quality of the final oil. (You may also be interested in: peanut oil production line >>)

Step 1: Degumming

Degumming removes colloidal impurities like phospholipids from crude peanut oil, as these impurities affect oil stability and appearance. Use two main methods: water degumming or acid refining degumming.

Water degumming uses the hydrophilic nature of phospholipids. Add hot water or dilute phosphoric acid to heated crude oil (60-85°C) while stirring. The gums absorb water and form aggregates, then removed through sedimentation or centrifugal separation. This process effectively removes most phospholipids along with associated proteins, glycosides, and trace metal ions.

The core equipment for degumming includes a degumming tank (also called refining tank or reactor). The tank features heating devices, stirrers, and systems for adding hot water or phosphoric acid.

Step 2: Deacidification

Deacidification removes free fatty acids (FFA) from crude oil. FFA causes oil rancidity and off-flavors while lowering the smoke point. Alkali refining is the most common method.

Add sodium alkali solution (sodium hydroxide solution) at specific concentrations to degummed peanut oil. The alkali neutralizes free fatty acids, forming soapstock (the main component of soap).

The soapstock absorbs other impurities (proteins, pigments, residual gums) and separates through settling or centrifugation. After alkali refining, washing the oil with hot water to remove residual soapstock and alkali.

Equipment for deacidification includes: deacidification tanks, alkali solution preparation tanks, alkali pumps, washing tanks, and centrifugal separators.

Step 3: Decolorization

Decolorization removes natural pigments (chlorophyll, carotene) and new pigments formed during degumming and deacidification, making the oil clear and transparent. Most use adsorption decolorization.

Under vacuum and heat (90-110°C), add adsorbents to peanut oil—typically activated bleaching earth, sometimes with small amounts of activated carbon. The clay absorbs pigments and other residual impurities (trace soapstock, metal ions). After thorough mixing for a set period, filtration completely separates the clay and absorbed impurities from the oil.

Decolorization equipment includes: decolorization tower (equipped with vacuum systems, stirring and heating devices), clay dosing machines, and vibrating filters or plate-and-frame filters.

Step 4: Deodorization

Deodorization is the final critical step in peanut oil refining. It removes volatile substances causing off-odors (aldehydes, ketones, hydrocarbons), residual free fatty acids, and solvents.

At high temperatures (above 200°C) and high vacuum, inject direct steam into the oil. The process uses volatility differences between oil and off-flavor compounds, using steam distillation principles to carry away odorous substances.

After deodorization, cooling and final filtration to produce the refined finished oil. This process also breaks down heat-sensitive toxins like aflatoxins.

The core equipment for deodorization is the deodorization tower, featuring complex internal structure with multiple layers, heat exchangers, and direct steam injection systems. Additional equipment includes vacuum systems (steam jet pump or mechanical vacuum pumps), thermal oil furnaces, heat exchangers, and finished oil cooling tanks.

Build Peanut Oil Refinery Plant Cost Analysis

The cost of building a peanut oil refinery plant varies significantly based on scale, automation level, equipment materials, facility infrastructure, and supporting facilities. The table below shows equipment costs for different scales (excluding equipment transportation, installation and commissioning, facility  infrastructure, and labor costs, etc):

Note: Investment costs depend on configuration, materials, and technical solutions. Final costs require specific project evaluation.

For example, a complete 5-ton/day semi-continuous peanut oil refining system costs about $95,000. Large-scale production line (100-150 tons/day) requires equipment investments of $550,000-$1000,000 or higher. (Related Post: Peanut oil extraction machine​ for sale >>)

Huatai Group Oil Refining Equipment Unique Features

Rich experience and reliable technology: With 37 years of professional experience and mature processes. We ensure stable equipment performance, high refining rates, minimal losses, and high-quality finished oil meeting national Grade 1 oil standards.

Multi-purpose and flexible design: Our equipment (especially semi-continuous systems) refines not only peanut oil but also rapeseed, tea seed, soybean, and sunflower oils, and other vegetable oils, helping you adapt to market changes.

Energy-saving design: Decolorization systems use a vacuum to improve efficiency. Deodorization system recovers heat energy, reducing steam consumption and operating costs.

Semi-continuous process advantages: Our semi-continuous equipment combines batch flexibility with continuous efficiency. While ensuring effective degumming, deacidification, and decolorization, it achieves continuous automated production in the deodorization section. This cost-effective solution suits medium-sized manufacturers particularly well.

Comprehensive technical services: We provide complete services from engineering design, equipment manufacturing, installation and commissioning, technical training to after-sales support, helping you successfully construct and produce your plant.

Conclusion

This guide covers the complete peanut oil refining process and estimated costs for building refining plants of different scales. Investing in a peanut oil refinery plant is a systematic project, and selecting the right supplier is a crucial step toward success.

Henan Huatai Intelligent Equipment Group, a renowned oil equipment manufacturer with over 37 years of experience, develops and manufactures edible oil refining equipment for all scales. Our business covers over 60 countries and regions worldwide. We welcome you to visit our factory anytime!