To prevent the development of plant diseases, irrigation water needs to be disinfected. The commonly applied cleaning methods do not allow the possibility of activation and enrichment of irrigation water with nutrients. The target of this study is to develop an environmentally friendly method for disinfecting and activating irrigation water by treatment with high‐voltage discharges in an electro‐hydraulic installation. The study used the following materials and equipment: a high‐voltage installation with an electro‐hydraulic spark gap, an EnSURE luminometer (Hygiena) to measure the level of hygiene of water and its solutions, AquaSnap Total (AQ100X) test tubes (Hygiena) to determine the total amount of adenosine triphosphate (ATP) in water, and an ITAN ionomer (Tomanalit) for measuring nitrogen compounds in water. Experimentally the following optimal parameters and technological conditions were determined and substantiated to reduce irrigation water pollution from 1210 RLU to 73 RLU and increase water content of nitrogen compounds from 1.2 mg L‐1 to 8.4 mg L‐1: an operating voltage of 19.9 kV, a capacity 0.145 μF, and a number of discharges of 2860 pcs. Water disinfected with high‐voltage discharges will be useful for agricultural irrigation since it can serve as a nitrogen fertilizer, which does not have any harmful effect on the environment.

No abstract

Electrohydraulic effect is used in various fields of industry and agriculture: for cleaning metal casting forms, cleaning pipes of power boilers, treatment of heating radiators, soil treatment and water disinfection. Existing technical means for water disinfection with high-voltage discharges are expensive, cumbersome and untransportable. Currently used installations use an operating voltage of 10-50 kilovolts, capacitors designed for a voltage of no more than 100 kilovolts, with a capacity of 0.025 microfarads. Water disinfection according to the conducted research can be carried out with a voltage of 10 kilovolts. (Research purpose) The research purpose is in developing and manufacturing a laboratory electrohydraulic installation for water disinfection, which has a technical novelty in terms of mobility and compactness for implementing a method of water disinfection at a voltage of no more than 10 kilovolts. (Materials and methods) During the research, next materials, equipment and devices were used: power supply; transformer; capacitor; forming gap; working body; shunt resistance. (Results and discussion) The principle of the electrohydraulic effect, which is a consequence of the occurrence of electrohydraulic shocks between high-voltage electrodes placed in a liquid, is the basis for the development and manufacture of the installation. Authors developed a structural diagram of a laboratory electrohydraulic unit for water disinfection. The article presents an experimental sample of a laboratory installation for water disinfection, which has a technical novelty in terms of mobility and compactness for implementing a method for water disinfection at a voltage of no more than 10 kilovolts. The installation consists of a power supply unit FA-5-1/300W, a high-voltage step-up transformer TDKS32-04, a capacitor K75-29A (16 kilovolts, 1 microfarad), forming a gap of metal balls with a diameter of 18 millimeters, a plastic working body made of ABS material, a shunt resistance of 1 kilohm. (Conclusions) They article shows the scientific and practical significance of the research results: a technical means for water disinfection, providing the possibility of conducting experimental laboratory studies of the electrohydraulic effect at a voltage of no more than 10 kilovolts.

The effect of microwave pretreatment on the exchange energy of forage barley was studied using the developed experimental setup. The novelty of the developed experimental setup in the summation of the power of microwave magnetrons in the waveguide, which provides an increase in productivity up to 50 kg/h while reducing energy consumption to 0.04 kW h/kg. The hypothesis of summation of the power of microwave magnetrons has been confirmed using a computer model in CST Studio. The average combined power of two magnetrons is 13 V A/m2. Using the method of planning the full factorial experiment, experimental studies of microwave pretreatment of forage barley of the second class with an exchange energy of 12 MJ/kg were carried out. Optimized significant factors affecting the pretreatment, such as grain moisture 16.5%, device power level 2, and the height of the waveguide end relative to the grain layer 41.7 mm. With these experimental parameters, the level of the exchange energy of forage barley will be 13.1 MJ/kg, which corresponds to forage barley of the first class. Microwave pretreatment of grain by increasing the exchange energy can increase the nutritional value of grain. Practical applications Increasing the exchange energy and nutritional value of forage barley will increase its digestibility by animals. It is proposed to use the developed microwave setup in agricultural farms to reduce energy consumption for grain pretreatment before feeding animals.

Relevance of developing the equipment for electro-hydraulic treatment of water and its solutions was substantiated. The device that is one of the electro-hydraulic spark gap installation components has been developed in order to eliminate the drawbacks of similar devices used. The application field of the device for electro-hydraulic treatment of solutions is crop production in agriculture. Electro-hydraulic treatment can be used to produce fertilizers in conditions of irrigation of greenhouse vegetable crops in personal subsidiary and peasant (farmer) farms. The installation, in addition to the cylindrical tank, contains a voltage source, a high-voltage transformer, an autotransformer, energy storage devices, rectifying cells, start-control devices and means of control and measuring. Electrodes are installed in this device, one of which has a technical scientific novelty. The tip of the negative electrode is hemispherical, which allows increasing the stored energy in the capacitor, to increase it in the discharge channel, increasing the length of the spark discharge in the liquid. The model of the device has been developed in order to substantiate the design parameters and operation modes. The developed electric diagram required for installation, runup and control of technological modes of electro-hydraulic impact on liquid media is shown. Actual model of the device is presented in photo content. The perspectivity of studying the electro-hydraulic effect is determined.