Rice

Rice milling is a yield business, and the yield is measured as unbroken grains.

Breakage is cumulative

Each drop, each screw conveyor and each pass through a high velocity line adds brokens.

• Bucket elevators with soft discharge instead of free fall.
• Belt conveyors in place of screws after milling.
• Low velocity pneumatic conveying where air transport is unavoidable.

Drying and fissuring

Grains dried too fast develop internal fissures that survive storage and break at the mill.

The handling system cannot repair this, but gentle conveying limits how much of the damage becomes visible.

Dust and husk

Husking and polishing release husk dust and bran, both combustible and both abrasive.

Aspiration at each machine, protection of the collector and housekeeping that removes settled dust are standard in a modern mill.

Storage

Paddy and milled rice both need aeration and insect control, and milled rice additionally picks up odours.

Clean, sealed silos with monitored temperature keep both quality and safety in range.

What to establish before buying equipment

• Head rice percentage at each stage, measured consistently.
• Moisture at intake and the drying profile.
• Aspiration volumes per machine.
• Storage time and the insect control method.

Rice stores well and fails slowly, which makes the failures easy to miss.

Moisture and temperature drive everything: above the safe moisture level, respiration, mould and insects all become possible, and a warm core in a cool bin moves moisture to the top of the bed where it condenses.

• Dry to the storage target before filling rather than correcting afterwards.
• Aerate to equalise temperature; the point is uniformity, not cooling alone.
• Monitor temperature at several depths; a hot spot is the first visible sign and it starts deep.

Rice handles easily, so the design question is breakage rather than flow.

Broken grains are a direct commercial loss, since whole grain commands the price. Every impact and every high-speed transfer produces them.

• Bucket elevators and belts rather than long pneumatic lines.
• Cascade chutes and low drop heights at every transfer.
• Aspiration sized for a coarse stream with a fine husk dust fraction.

Rice dust and husk dust are explosible, and the plant risks are the familiar grain ones.

• Explosion protection and isolation on elevators, filters and bins.
• Housekeeping with documented frequency.
• Bin entry procedures; flowing grain traps a person in seconds.