Liquid Nitrogen Cryogenic Pulverizer

What Is a Liquid Nitrogen Pulverizer?

A Liquid Nitrogen Pulverizer (also called a cryogenic grinding mill, liquid nitrogen grinding machine, or cryogenic pulverizer) is an ultra-low-temperature grinding machine that uses liquid nitrogen as the cooling medium. Its core principle is to instantly embrittle materials at -196°C, breaking through the bottleneck of conventional grinding, which cannot handle “high-toughness, high-elasticity, heat-sensitive, high-viscosity” materials.

Compared with ordinary mechanical pulverizers, the Liquid Nitrogen Pulverizer generates almost no frictional heat during grinding. It effectively prevents oxidation, denaturation, or deactivation of heat-sensitive ingredients, while avoiding stringing, agglomeration, or melting of polymer materials caused by temperature rise—thus producing uniform, stable ultrafine powders.

Core Working Principle of Liquid Nitrogen Pulverizer

The grinding process of the liquid nitrogen pulverizer consists of three major stages—pre-cooling, pulverizing, and separation—all completed in an inert, ultra-low-temperature environment:

▪ Pre-cooling & Embrittlement: Material enters the pre-cooling bin and fully contacts the injected liquid nitrogen, instantly cooling to -196°C and rapidly freezing below its glass transition temperature to become brittle.

▪ Low-Temperature Grinding: The embrittled material enters the grinding chamber and is forcibly crushed by high-speed rotating hammers or a toothed disc; being in a brittle state, it is easily ground fine.

▪ Gas-Solid Separation & Circulation: Fine powder is collected through a grading screen or air classifier; the cold gas can circulate internally, significantly saving liquid nitrogen consumption and reducing operating costs.

Why Polymer Plastics & Elastomers Need Cryogenic Grinding

he liquid nitrogen pulverizer can finely grind materials to 60-200 mesh. Especially for materials such as TPU, TPE, EVA, PTFE, nylon (PA), PE, PP, PET, and UHMWPE, which are extremely tough or elastic at room temperature, ordinary pulverizers struggle to grind them fine and may even cause stringing or melting due to frictional heat.

Liquid nitrogen instantly embrittles these materials, making the Liquid Nitrogen Pulverizer ideal for the preparation of micronized powder before high-quality plastic granulation, extrusion, or modification—ensuring good powder fluidity and a controllable particle size distribution.

Typical Applicable Polymer Materials

▪ Thermoplastic elastomers: TPU (polyurethane elastomer), TPE, TPR, EVA
▪ Engineering plastics: nylon PA11 / PA12 / PA66, PTFE, UHMWPE, PET

Wide Range of Applications | What Can the Liquid Nitrogen Pulverizer Process

A1. Polymer Plastics & Rubber (Core Application)
Thermoplastic elastomers (TPU, TPE, TPR, EVA) are highly elastic at room temperature and rapidly embrittle into a glassy state at ultra-low temperatures. Engineering plastics such as nylon (PA11, PA12, PA66), PTFE, UHMWPE, and PET can also be finely powdered via the Liquid Nitrogen Pulverizer.

A2. Food & Spices
High-oil / high-sugar materials: sesame, peanut, walnut, cocoa bean, coffee bean—easily ooze oil or agglomerate at room temperature.
Volatile spices: pepper, mustard, star anise, nutmeg—low temperature fully locks in aromatic volatile oils, preserving the aroma to the greatest extent.

A3. Biomedicine
Plant/animal cell wall breaking: Ganoderma spore, pollen.
Heat-sensitive Chinese medicinal materials: ginseng, antler, Panax notoginseng (sanqi), Cordyceps—preventing active ingredients from oxidizing or denaturing/deactivating under the high temperature of room-temperature grinding.

System Composition | Components of the Liquid Nitrogen Pulverizer

A complete liquid nitrogen pulverizer cryogenic grinding system consists of the following units, forming a continuous, enclosed automated production line:

Feeder → Screw feeder → Pre-cooling bin → Screw feeder → Pulverizer main unit & fan → Cyclone separator, screw discharge & return air pipe, pipelines, liquid valve → Frequency converter → Electrical control cabinet.

Technical Specifications | Main Unit Parameters

Equipment Configuration | Complete Cryogenic Grinding System

Main Component Material Specification

Why Choose Beisu Liquid Nitrogen Pulverizer?

▪ Ultra-Low-Temp Embrittlement: -196°C liquid nitrogen cryogenic treatment overcomes the grinding challenge of high-toughness, heat-sensitive, and high-viscosity materials.

▪ Stable Quality: Whole-process low temperature with no frictional heat; powder does not oxidize, agglomerate, and has uniform particle size.

▪ Fine Pulverization: Processing fineness 20-250 mesh; polymers typically reach 60-200 mesh.

▪ Energy-Saving Circulation: Internal cold-gas circulation significantly reduces liquid nitrogen consumption and operating costs.

▪ Food-Grade Material: The whole machine and pipelines are made of 304 stainless steel, meeting hygiene and corrosion-resistance requirements.

▪ Variable-Frequency Control: Main motor, fan, and conveyors are all equipped with frequency converters (Delta), allowing flexible process parameter adjustment.

Frequently Asked Questions | Liquid Nitrogen Pulverizer Buying Guide

Q: What is the working principle of a liquid nitrogen pulverizer?

A: The liquid nitrogen pulverizer uses the -196°C ultra-low temperature of liquid nitrogen to rapidly freeze the material in the pre-cooling bin below its glass transition temperature and embrittle it. The embrittled material then enters the grinding chamber and is crushed by high-speed rotating hammers or a toothed disc. Finally, the fine powder is collected through a grading screen or air classifier, with the cold gas circulating internally to save liquid nitrogen consumption.

Q: Why do polymer materials such as TPU, TPE and PTFE need cryogenic grinding?

A: Materials such as TPU, TPE, EVA, PTFE, nylon (PA), PE, PP, PET and UHMWPE are extremely tough or elastic at room temperature; ordinary pulverizers struggle to grind them fine, and frictional heat easily causes stringing or melting. Liquid nitrogen instantly embrittles them, enabling fine grinding to 60-200 mesh—ideal for preparing micronized powder before high-quality plastic granulation, extrusion, or modification.

Q: What materials can the liquid nitrogen pulverizer process?

A: It is mainly used for three categories: (1) polymer plastics & rubber (TPU, TPE, TPR, EVA, nylon PA11/PA12/PA66, PTFE, UHMWPE, PET); (2) food & spices (sesame, peanut, cocoa bean, coffee bean, and volatile spices such as pepper, mustard, star anise); (3) biomedicine (Ganoderma spores, pollen, and heat-sensitive Chinese herbs such as ginseng, antler, Panax notoginseng, Cordyceps).

Q: What is the fineness and capacity of the liquid nitrogen pulverizer?

A: The equipment’s product particle size range is 20-250 mesh; polymer powders typically reach 60-200 mesh. Production capacity is 30-150 kg/h, depending on raw material characteristics and configuration.