# Milk Processing Plant 3D Walkthrough

Follow milk through a dairy plant: tanker, silos, separator, HTST pasteurizer, carton filler, case packer and palletizer

By Casper Boutens

Topic: Engineering

[Open the interactive Jig](https://ask.jig.com/j/CfSD0SUzvf2D)

## Transcript

### 1. From tanker to pallet

This is a model of a milk plant, shown from above like a digital twin\. Milk arrives by truck at the back left, travels clockwise through cleaning and heating, and leaves at the front left as stacked boxes of cartons\. Drag to look around\.

Pinch or scroll to move closer\. Layout and sizes are illustrative, not one real plant\.

### 2. The tanker arrives

A road tanker brings chilled milk from the farms, usually 5,000 to 10,000 litres at a time\. A hose is coupled to a clean steel inlet, and a pump draws the milk through an air eliminator toward the silos\.

Milk arrives at about 4 °C\. The plant tests a sample before it is accepted\.

### 3. Raw milk silos

The milk waits in tall insulated silos, often holding 30,000 litres or more\. Here one silo is cut open\. A slow propeller called an agitator keeps it gently stirred, so the cream does not rise to the top\.

The milk stays at about 4 °C, usually for no more than a day or so\.

### 4. Clean and mix

A balance tank feeds the line at a steady rate\. The separator spins milk like a very fast salad spinner, flinging out tiny bits of dirt and splitting cream from skim\. Cream is added back to set the fat for each product, and the homogenizer pushes milk through a tiny gap so the cream stays mixed in\.

Homogenizers work at roughly 180 to 200 bar, about 100 times the pressure in a car tyre\.

### 5. Pasteurize: 72 °C for 15 seconds

In the plate heat exchanger, milk and hot water flow on opposite sides of thin steel plates\. The milk is heated to at least 72 °C and held there for 15 seconds in the looping holding tube, then cooled straight back down\. That kills disease\-causing germs without boiling the milk\.

If milk is ever too cool, the divert valve sends it back to the start in about a second\. Try it\.

### 6. Filling the cartons

Cold pasteurized milk waits in a buffer tank, then feeds the carton filler\. The machine folds a flat blank into a sleeve, seals its bottom, fills it, and folds and heat\-seals the gable top\. Look for the maker plate on the front of the machine\.

Cartons are paperboard coated with a thin layer of plastic, so they hold milk without soaking through\.

### 7. Into boxes

The finished cartons ride a conveyor into the case packer\. It folds flat cardboard into a case, sets a group of cartons inside, and closes the flaps\. Out come sealed boxes, ready to stack\.

Case packers can fill dozens of cases every minute\.

### 8. Onto the pallet

A gantry palletizer lifts each box and sets it down in a planned pattern, layer by layer\. A full pallet is wrapped in stretch film and moved to the cold store, ready for delivery trucks\.

The pallet is the common North American size, 48 by 40 inches \(about 1\.2 by 1 metre\)\.

### 9. The whole line

From truck to pallet, the milk stays inside closed steel pipes and machines, and stays cold except for those 15 hot seconds\. Switch between the milk route and the temperature view to see where heat is used\.

The plate heat exchanger reuses the heat of hot milk to warm incoming cold milk, recovering around 90 percent of it\.