LT5620B - Thermal weed killing method and device - Google Patents

Abstract

The invention is related to agriculture and can be used as thermal weeds killing method and device, for protecting cultivated plants from thermal killing. The aim of this invention is a weed killing method and device with cold foam protection, whichwould protect cultivated plants in the furrow from thermal killing while thermal killing of weeds by moist water steam is done. This aim is achieved by additionally fixed cold foam producing generator for cultivated plants coating by cold foam device on the mobile weed thermal killing device. Before thermal weed killing, the cold foam is distributed in the furrow on the cultivated plants and protects it from thermal killing.

Description

The invention relates to agriculture and can be used as a thermal weed control method and device for protecting crop plants from thermal foam destruction.

Known method of killing plants using hot foam (US 2005/0116071). This method is used to remove weeds for maintenance of railway tracks, footpaths, etc. in hard to reach places. The disadvantage of this method is that such weed control is not possible in the furrows of cultivated plants, because weed killing also destroys the cultivated plants.

Weed control and pest control by hot foam is also known (US al. No. 5578111, 1996). Hot foam, which has a temperature close to the boiling point of the water, is spread on the plants, damaging their wax layer, causing dehydration and destruction of the plants. The disadvantage of this method is that this thermal destruction of weeds destroys all plants, including crops.

The closest approach to the proposed method and installation is a thermal weed killer with flame protection for crop crops with CO ₂ gas. Crop plants are protected from the direct thermal effects of flame by CO ₂ gas. Cold CO ₂ gas is released above the crop furrow, extinguishes the flame spread and cools the combustion products in the crop furrow. The disadvantage of this technique is that CO ₂ gas protection is ineffective in dampening weeds with wet water vapor. (Tei F., F. Stagnaro, Granier A. Preliminary results on physical weed control in spinach. European Weed Research Society. 5 ^th EWRS Workshop on Physical and Cultural Weed Control in Pisa, kaly, 11-13 March 2002, p. 164- 171).

The object of the present invention is to provide a method of thermal eradication of weeds and a device with a cold foam protection which would protect crop plants in the furrow from thermal destruction by thermally eradicating the weeds with moist water vapor.

This objective is achieved by the addition of a cold foam generator and a cold foam applicator to the weed thermal eradication unit. Hot foam is used for thermal weed control and cold foam applied to plants (cultures) protects them from thermal destruction, which is an essential distinguishing feature of the proposed thermal weed control method and device that achieves the object of the invention.

In the drawings, Figs. 1 shows a schematic diagram of a weed thermal eradication device with a cold foam generator and a foam applicator; FIG. 2 is a schematic diagram of a weed thermal eradication device for protecting crop plants in froths with cold foam; FIG. 3 is a schematic diagram of a weed thermal eradication technology without crop protection, with uniform humid water vapor release distances A from the crop; FIG. 4 principle scheme of thermal weed control for the protection of crop plants using cold foam at uniform humid water vapor release distances A from the crop plants covered with foam; FIG. 5 - Temperature variation during thermal weed control for crop protection using cold foam and no foam protection.

Thermal weed control consists of the following operations: spreading cold foam in the furrows of cultivated plants, spreading thermal weed killer in the row.

The thermal weed control unit consists of: tractor with mounting structure 1, water steam boiler 2, water steam generators 3, foam generator 4, foam feed duct 5, foam spreader 6.

The device works as follows. As the tractor I moves, the cold foam produced in the foam generator 4 passes through the foam feed duct 5 to the foam spreaders 6 and spreads over the crop plants in the grooves 7. After 2-3 seconds, the wet water steam produced in the steam boiler 2 is supplied to the steam generators 3. In this way, the weeds that germinate in the row 8 are thermally destroyed by moist water vapor, and the sprouted crop plants in the furrows 7 are protected from the influence of the high temperature by the spread of cold stable foam on the crop plants.

The test unit of the proposed weed thermal eradication plant with cold foam protection of crop plants was manufactured and tested in the Laboratory of Thermal Measurements of the Lithuanian University of Agriculture. Temperature was measured during the weed thermal extermination at the point of steam release in the interstices and at the growth site of the cultivated plants in a furrow covered with cold foam. By thermally destroying weeds with moist water vapor without spreading foam on the crops on a level surface of the crop, the temperature of the crop plants reached 80 ° C, thus the crops are thermally destroyed. The application of cold foam on the cultivated plants reached a temperature of 30-40 ° C. At this temperature, crop plants are protected by cold foam from thermal destruction by ecologically killing weeds in a smooth soil profile. All test conditions were the same in all cases.

Claims (2)

1. The method of thermal weed control by spreading the weed-killing medium on the weeds, characterized in that, in addition to the thermal weed control, the cold foam is applied to the crop furrows to protect them from thermal destruction. 2. A weed thermal eradication device comprising a tractor with a mounted structure, a water steam boiler, water steam diffusers, characterized in that there is additionally a foam production generator, a foam feed duct, a foam diffuser.