SU843866A1 - Method of soil desalinization and desolonetzization - Google Patents

Description

one

The invention relates to agriculture, in particular to the reclamation of saline soils.

In modern agriculture, methods are known for soil desalinization and soil pickling by the method of electroformation, which means that from sources of direct or pulsed currents through the electrodes immersed in saturated soil horizontally or vertically, voltage is applied to the reclaimed area 1.

There is a known method of electro-reclamation of saline soils, which consists in the fact that from a direct current source a voltage is applied horizontally across the electrodes immersed in the water-saturated soil to the reclaimed area. In the known method, a method of changing poles on the electrodes is proposed, which contributes to uniform wear of the electrodes {2.

However, these methods do not reduce the overall consumption of the material of the electrodes, this is due to the following.

In the process of electrolytic reclamation, electrolysis of water occurs with the deposition of ions at the negative electrode and HE at the positive one. The OH ion donates two electrons to the positive electrode and turns into an oxygen atom, adsorbed

on the surface of the anode, and the hydrogen cation, repulsed back into the soil by the electric field of the positive electrode

OH - 2nd Oads + H +.

Oxygen adsorbed on the anode surface, forming local microelements, causes corrosion of the positive electrode.

In addition, during the passage of a constant electric current through saline soil, the anode is oxidized.

Fe - 2e-Re2 +.

The aim of the invention is to reduce the consumption of electrode material and increase the intensity of the desalinization process.

The goal is achieved by passing positive current polarity pulses with a duty cycle of 2–4 and negative current pulses with a duty cycle of 6–8 at a ratio of amplitudes of positive and negative pulses of 8–10 and with the same frequency of 50 Hz.

In saturated soil, when a pulsed current is passed through, the ions have a directional motion according to their charge; to the cathode, under the action of electroosmosis, the water has moved to water desalination; 5Y (kg-E1 8/00 g pdchvy)

Table 1

Water extraction of the soil after desalinization,% (mEq / 10b g of soil) from water, which carries the majority of the salts. During desalinization, polarization of the near-electrode spaces occurs. Potentials of double layers near the electrode-5

Table 2 of the walls are directed towards the external electrical zero. Double layers, mainly formed by H + and OH- ions, are much more mobile than metal ions and acid residues, which are separated during desalinization. Reverse (depolarizing) pulses of comparatively small intensity and duration destroy these double layers, providing a more productive use of electrical energy for desalination and at the same time reducing the effect of oxidizing ions on the anode material. This makes it possible to increase the intensity of the brine while at the same time saving the material of the electrodes.

The amplitude and duration of the reverse pulse should be such that during its passage the surface areas of the positive electrode have time to recover to low valence compounds. The amplitude and duty cycle of the forward and reverse pulses are set depending on the properties of the treated soil. The most favorable mode of desalinization occurs with a 2–4 forward pulse duty cycle, a 6–8 reverse pulse duty cycle, a 8–10 forward and reverse pulse amplitude ratio, and a frequency of 50 Hz.

The drawing shows the shape of the pulses.

Example. The washing of the gray-earth serozem saline was conducted under the influence of a pulsed current with an inverse impulse depolarization for 12 h.

To obtain comparative data, flushing of the same type of soil was performed in parallel under the influence of direct current and pulsed current without depolarization.

In all three series of experiments, the same power of the sources of electrical energy was maintained and the ameliorative effect and material consumption were determined.

electrodes. The material of the electrodes was Art. 3, the parameters of the pulses: the duty cycle of the forward pulse 4, the duty cycle of the reverse pulse 6, the ratio of the amplitudes of the forward and reverse pulses 8, the current strength.

The data are given in table. 1 and 2. The current density is 21, 23 mA / cm and frequency 50 Hz. The use of the proposed method of desalinization and soil solubilization using the method of electromiliation under the influence of pulsed current with reverse impulse depolarization provides, in comparison with the existing methods, an increase in the intensity of electromelioration, a significant reduction in the consumption of electrode material.

Claims (2)

1. Bondarenko N. F. Physical bases of land reclamation. L., 1975, p. 137. 2. Vadyunina, A.D., et al., Moscow State University Bulletin, series “Biologists, soil science, No. 6, 1973, p. 106-112 (prototype). g 24-ff 90 t