Detergent Powder

A detergent tower produces a fragile particle on purpose, and everything downstream has to respect that.

Attrition

Spray-dried granules are hollow spheres, and they collapse under impact and in high velocity conveying.

The debris is fine dust that changes bulk density, fills the carton differently and increases enzyme dust exposure.

• Belt or bucket conveying in place of long pneumatic runs where layout allows.
• Dense phase conveying at low velocity where pneumatic transfer is necessary.
• Minimal drop heights into silos and cartons.

Segregation of the blend

Post-dosed enzymes, bleach granules and perfumes differ in size and density from the base powder, and every fall sorts them.

Mass flow silos, blending close to packing and short, controlled transfers keep the carton representative of the recipe.

Caking and reactivity

Hygroscopic salts take up moisture, and moisture lets components react with each other in storage.

Dry air, sealed silos and limited residence time are the controls, with temperature kept stable to avoid condensation inside the vessel.

Enzyme exposure

Detergent enzymes are respiratory sensitisers, and the exposure target is far below a general nuisance dust limit.

Enclosure, extraction at dosing points and monitoring are standard practice in this industry for that reason.

What to establish before buying equipment

• Granule strength and the acceptable fines increase across the line.
• Particle size and density spread across all blend components.
• Humidity control in storage and packing areas.
• Enzyme exposure limit and the control strategy that meets it.

Detergent powder is engineered to dissolve, which is exactly what makes it difficult to store.

It takes up moisture readily, and the surfactants and builders in it then make it tacky and finally solid. Spray-dried grades also hold a lot of air, so the apparent density varies with how the silo was filled.

• Seal and condition the store; this is the whole control.
• Allow deaeration after filling before any feeder takes product.
• Expect consolidation and size the outlet for the stood condition.

The design has to handle a light, aerating, hygroscopic and mildly abrasive powder.

Deaeration volume, generous outlets and dry conveying air are standard. Enzyme-containing formulations add a containment requirement, because enzyme dust is a respiratory sensitiser.

• Dry conveying air with a stated dew point.
• Deaeration before feeders; gravimetric dosing where the recipe matters.
• Closed transfer where enzymes are present.

Detergent dust is combustible, and enzyme-containing products carry a sensitisation hazard.

• Explosion protection from measured values for the formulation.
• Closed handling and exposure monitoring where enzymes are present; sensitisation is permanent once established.
• Eye and skin protection where handled open, since the dust is alkaline and irritant.