High-Pressure Homogenizer

Overview

A high-pressure homogenizer reduces the size of dispersed droplets and particles in a liquid so the product stays uniform and does not separate. In milk it breaks fat globules from a few microns down to under a micron, so cream no longer rises; in emulsions and sauces it produces a fine, stable dispersion. The machine is a positive-displacement plunger pump: three plungers driven off a common crankshaft draw product in and force it out at up to 200 bar, and that pressurized stream is then pushed through a narrow adjustable gap in the homogenizing valve. The combination of shear in the gap, cavitation as pressure drops, and impact against a ring downstream is what actually tears the globules apart. Pressure, not flow, does the work, so the valve sets the result and the pump simply delivers a steady high-pressure feed.

How it works

Product enters the High-Pressure Pump Block, a solid forged 316L block bored for three ceramic plungers. On each intake stroke a spring-loaded suction valve opens to admit product; on the delivery stroke it closes and a discharge valve opens, so the plungers deliver a near-continuous high-pressure flow. The plungers are sealed by a Plunger Packing Set stack of chevron seals cooled by water through a lantern ring, since the packing is the part that wears.

The reciprocating motion comes from the Power End: a three-throw forged crankshaft turns connecting rods and crossheads that convert rotation into straight-line plunger travel, geared down from the Main Drive Motor through V-belts and a reduction gear set. The crankcase is splash- and pressure-lubricated by the Cooling & Lubrication System system, which also feeds cooling water to the plunger packing and rejects heat through an oil cooler.

The pressurized product then reaches the Homogenizing Valve Assembly. A carbide valve head is loaded against a seat to form a gap only a few microns wide; the Valve Actuator sets how hard it is loaded, and that load fixes the homogenizing pressure. Product accelerates through the gap, cavitates, and strikes an impact ring, completing the break-up, a second stage then back-pressures the first for a tighter result. The Control Panel ramps the motor through a variable-frequency drive, holds the pressure set-point, and trips the machine on overpressure or low oil pressure.