Blower (Mist) Pump Sprayer for Chilli

A blower or mist pump sprayer is a petrol-engine air-assisted backpack sprayer used in dense canopies of chilli, cotton, brinjal and orchard crops. Unlike a hydraulic-pressure knapsack, it atomises spray droplets in a high-velocity air stream that carries them through the canopy and onto leaf undersides.

Function

A small two-stroke engine drives a centrifugal blower; spray liquid is introduced into the air stream at the nozzle, where shear forces shatter it into fine droplets. Because of the air assist, much higher chemical concentrations and much lower water volumes per acre can be used than with a Knapsack Battery Sprayer.

Design and specifications

The widely sold STIHL SR 450 is a reference unit: 63.3 cc engine, 14-litre tank, 90 m/s air velocity and a maximum spray range of around 48 feet. Indian-made "machine sprayer" configurations adopt similar layouts. Equivalent dual-mode units convert to dust applicators without tools.

Operation

The operator slings the unit on the back and aims the discharge tube at the canopy from below or from the row centre. Compared with hydraulic-pressure spraying, mist-blower application gives better canopy penetration in tall, dense crops such as red chilli, and is rated by ICAR-CIAE plant-protection equipment evaluations as the most efficient hand-held option for such canopies.

Subsidy and adoption

Engine-driven mist sprayers are listed under SMAM plant-protection-equipment categories. Adoption is concentrated in commercial chilli, cotton, orchard and grapevine cultivation; for very large parcels, operators substitute a tractor-mounted air-blast or boom sprayer (Tractor Mounted Sprayer) or an Agri Drone Sprayer.

References

SR 450 Backpack Mist Blower. STIHL.