Electrosol Spraying for Agricultural Applications

1. Introduction

Electrostatic spraying uses high voltage to produce an ultrafine spray and to apply it directly to plant foliage. This dramatically cuts down pesticide consumption and eliminates soil contamination with pesticides.

Electrostatic sprayers, however, tend to being clogged when the spray and/or ambient air contains suspended particles like mud, sand or dust. Furthermore, conventional sprayers are bulky and require high-voltage cables. This makes them unsuited for small plots of land, unsafe and expensive.

More reliable, compact and safe and less expensive sprayers and spraying methods are thus desired.

The project is aimed at developing electrosol technology that provides such improvements.

2. Project Description
2.1. Improvements in the Method and Apparatus

Instead of a normal liquid spray, the method may use a pretreated liquid-gas mixture. No precipitation of sand, dust and mud then occurs in or on the sprayer. Its clogging is thus ruled out.

Self-excited oscillations generated during electrosol formation, and forced pesticide electroprecipitation contribute to high performance.

Special sprayers have been developed for these purposes.

A high-voltage device (HVD) is used that consists of a control block and a high-voltage converter connected to it with a common electric cord. The control block supplies low voltage which is then converted to high voltage. The converter is placed near the sprayer for improved safety and reduced cost.

2.2. Characteristics and Specifications of High-Voltage Device

2.2.1. Safety
(i) No high-voltage cables are used, for the high voltage is generated in the immediate neighborhood of the sprayer.
(ii) A spark suppression system is provided that uses stabilization current and also switches HVD off as the sprayer approaches the ground.
2.2.2. Optimum operation due to current stabilization.
2.2.3. Compactness, light weight and reliable design.
2.2.4. Self-contained power supply is possible.

Specifications

Target voltage 40 kV
Target current 150 A
Control block input voltage DC 12V Max.
Input power 10 VA
Weight 0.3 kg Min.

2.3. Performance

The development was tested and partly implemented in farming in some of the Newly Independent States (NIS). The consumption of pesticides was found to drop 2- to 5-fold. No loss of spray from the foliage was observed at wind velocities up to 5 m/s. Soil contamination during spraying was practically eliminated.

The foliage was found to be covered with spray on both sides, which enhanced the pesticide effects.

Apparently, cleaner food can thus be produced without sacrifice of the intensity of farming. The number of spray treatments may be minimized, resulting in a minimum exposure of operators.

3. Novelty

The method and devices for it are believed to patentable.

4. Marketing

The method and equipment need adjustments for each of the following application categories: (1) indoor and soil-free growing, (2) large-area and (3) small-area outdoor farming.

Among other things, electrosol sprayers with compact electric chargers were conceived for small private gardens. They offer 5 to 6 times lower pesticide consumption rates and therefore cleaner food, reduced pollution and material savings. Their pilot tests were successful.

The NIS offer a vast market for electrosol sprayers. Ukraine alone has about 15,000,000 small private gardens while no sprayers of Western make are suited to conditions prevailing anywhere in the NIS.

China and other countries with very small plots of farming land, and arid regions with their typical high contents of dust in the air, like Middle East and parts of Africa and North America, also may be potential markets.

5. Applications

In farming, the development may be used for spraying with pesticides, growth stimulants or fertilizers and for watering.

DSc., Prof. William Zadorsky,
Academician of the Ukrainian Ecological Academy, 
Ukrainian State University of Chemical Engineering.
Pridneprovie Cleaner Production Center
Tel: +(380) 567 440210
Tel/fax: +(380) 562 470813

    http://www.crosswinds.net/~usuce/index.html
    http://www.incubator.f2s.com
    http://www.zadorsky.8m.com