Mist Blower Sprayer

A mist blower is a petrol-engine air-assisted backpack sprayer that uses a high-velocity air stream to atomise liquid pesticide and project droplets through the canopy of tall and dense crops. It is the standard plant-protection tool for orchards, plantation crops and lodged or canopy-heavy field crops.

Function

A two-stroke petrol engine drives a centrifugal fan that produces a directed air stream; spray liquid from the on-board tank is metered into this stream and is shattered by aerodynamic shear into fine droplets. Air-assist gives much deeper canopy penetration than hydraulic pressure alone and supports lower water volumes per acre.

Design and specifications

The STIHL SR 450 is a widely sold reference unit: a 63.3 cc two-stroke engine producing 2.9 kW (3.9 HP), a 14-litre tank, 542 cfm air volume, 90 m/s air velocity and a maximum spray range of about 48 feet. Empty weight is around 12.8 kg. The unit can be converted between mist (liquid) and dust (granular) modes without tools, doubling as a duster.

Operation

The operator straps the unit on the back, throttles up the engine and aims the discharge tube at the canopy. Walking pace is matched to the desired application rate per acre. The mist blower is preferred over a Knapsack Battery Sprayer in coconut, areca, mango, sapota, citrus and grapevine, and over a 4 Stroke Knapsack Sprayer in tall cotton, chilli, banana and sugarcane.

Subsidy and adoption

Mist blowers are listed under SMAM plant-protection-equipment categories and qualify for individual-farmer subsidy. The class is also widely available through Custom Hiring Centres (Agri Machinery Dealer Ecosystem).

References

SR 450 Backpack Sprayer. STIHL.