Glossary of Solvent Extraction Plant Equipment Terms

Solvent extraction plant equipment follows a defined process sequence, and each stage has its own name and function that can be confusing to a buyer encountering the terminology for the first time. This glossary walks through the equipment in roughly the order it appears on a processing line.

Seed preparation equipment

Seed Cracker — Breaks whole oil seeds into 4–6 uniform pieces using counter-rotating corrugated rolls, reducing downstream flaking power consumption by 20–30% and protecting flaker rolls from damage by oversized seed.

Breaker Rolls — Used for preliminary breaking of oversized seeds or seed clusters before cracking or flaking, using counter-rotating rolls with smooth, corrugated, or toothed surfaces depending on the material.

Conditioner — Adjusts seed moisture (to a 10–12% target) and temperature (60–70°C) before flaking, making the seed pliable for efficient processing and reducing flaking power consumption by 15–20%.

Cooker — Provides more intensive thermal treatment than conditioning (20–40 minutes at 60–70°C in a multi-stage design), denaturing proteins and breaking down cell walls for seeds that need more preparation before extraction.

Flaker Machine — Produces thin, uniform flakes (0.25–0.35mm) from prepared seed using precision-ground hardened rolls, increasing surface area 10–15× over cracked seed to improve extraction efficiency.

Oil extraction equipment

Expander & Extruder — Transforms conditioned material into dense, porous pellets under pressure and steam injection, increasing bulk density 40–50% and reducing solvent consumption by 15–25%. "Expander" and "extruder" are generally used interchangeably in this context.

Pre-Press Machine (Expeller / Squeezer) — Mechanically extracts 60–70% of available oil before solvent extraction, using a screw press or hydraulic press, leaving a cake with 12–18% residual oil for the solvent extraction stage to finish.

Post-extraction equipment

Drier Cooler — Reduces extracted meal temperature from 100–110°C to approximately 40°C and moisture to 10–12%, using counter-current or cross-flow air systems, for safe storage and handling.

Steam Radiator / Heat Exchanger — Heat exchange equipment used across the plant, including fin tube radiators for space heating and shell-and-tube exchangers for high-pressure process applications.

Supporting hydraulic and material handling equipment

Hydraulic Cylinder — Provides linear force and motion for equipment throughout the plant, built for pressures up to 210 bar with bore sizes from 40mm to 250mm.

Hydraulic Power Pack — A self-contained system combining pumps, motors, reservoirs, filtration, and control valves into one package, typically sized from 2–50 HP, powering hydraulic cylinders and other equipment across the plant.

Hydraulic Bag Stacker — Automates stacking of packed meal bags (25–50 kg) to heights of 2–3 meters, reducing manual handling labor.

General terms

TPD (Tonnes Per Day) — The standard capacity measure for solvent extraction equipment; Pragya's core process equipment (cracker through drier cooler) is generally built across a 50–500 TPD range.

Residual Oil / Cake — The oil remaining in the solid material (cake or meal) after a processing stage; pre-pressing typically leaves 12–18% residual oil in the cake for solvent extraction to recover.

Meal — The solid byproduct remaining after oil has been extracted, valued in its own right (particularly for its protein content in crops like soybean) once cooled, dried, and stabilized.

This glossary covers the equipment types most commonly discussed when planning or specifying a solvent extraction line; the linked product pages carry full specifications for each machine. For a stage-by-stage read, see our guides to seed cracking, conditioning, cooking, flaking, expanding, pre-pressing, and meal cooling.

Availability in India

Designed and built at Pragya's Pithampur (Indore) works and supplied to oil seed processing plants across India. Equipment is fabricated to the relevant IS standards, delivered by road to your plant, and installed and commissioned on site by our own engineers, who also train your operators.