LT2010008A - Process for treatment and decontamination of sewage - Google Patents

Abstract

The present invention relates to the treatment of municipal, industrial and livestock sewage by use of cavitation technology as well as to diminishing microbial contamination in wastes.@

Description

1

The present invention relates to liquid and liquid media cavitation cleaning technology for wastewater treatment of utility, industrial and agricultural livestock complexes, as well as for reducing microbial concentrations in wastewater, and may be adapted to treatment plants and water supply systems.

Recently, liquid chlorine, ozone and ultraviolet rays are used to decontaminate wastewater. This requires large intermediate contact containers to ensure mutual contact for at least half an hour. Chlorine decontamination rates are 91%, ozone - up to 96%, ultraviolet radiation - up to 47%.

Wastewater decontamination by cavitation is carried out with the help of liquid turbulent flows. Under the influence of hydrodynamic vibrations, cavitation bubbles appear and disappear in the liquid, while the phase transition surface is stimulated, local temperature and pressure increase. In addition, at the time of the emergence and disappearance of cavitation bubbles in gas-filled cavities, conditions are created for the formation of electrical charges, which are manifested by electric and magnetic fields. In this way, the effect of cavitation in the liquid simultaneously results in thermobaric and electromagnetic fields.

The peculiarity of the cavitation method is that the decontamination of the bacteria in the effluent occurs through mechanical destruction due to the impact waves that occur during the cavitation process. At the same time, bacteria are active and thermobaric and electromagnetic fields are formed. A known method and device for using a cavitation reactor (see U.S. Patent No. 6,505,548, CO2F 1/34, 2003), in which the fluid flowing in a tube changes in cross-section to cause cavitation. 2

However, the effectiveness of this method and device is low, as the effect of cavitation is on a small area of fluid and is short-lived. Known Wastewater Treatment Methods Principles of Operation Based on Aeration (see UA Patent No. 50574, C02 F 3/02; 3/12, 2005) or Introducing Natural Gas into a Liquid to be Purified (See UA Patent No. 28220, C02F 9/00 , 2000). There is also known a method for treating wastewater (see UA patent No. 32029, CO2F 3 / 00,2008) by which wastewater is subjected to periodic aeration, mixing, precipitation, removal of sediment and circulating flow of purified water into the first, second and third stage reactors.

The disadvantage of this prototype is that its implementation requires additional equipment for air supply and fluid mixing, which complicates the time (in time) of the liquid purification process and does not allow the wastewater to be decontaminated, as a single flow of liquid through the cavitation zone slows down the speed of the cleaning process and bubbles in the cavitator reach 2 -5mm., Are not effective enough.

The goal is to create more efficient and faster wastewater treatment by introducing additional technological operations into the well-known wastewater treatment process and at the same time decontaminating the treated water. The object of the invention is achieved by the fact that the treated wastewater is collected into the receiving tanks, before separating the solid fractions, which are subjected to repeated circulation cavitation by mixing with air portions. In this way, the large fractions in the effluent are passed through the cavitator several times and shredded and mixed. Periodically changing pressure in the cavity creates shock waves that mechanically destroy bacteria. There is also a biological effect on the fluid to be cleaned, since at the same time, air is supplied in portions into the cavitation zone in the form of gas bubbles from 0.2 to 0.4 mm. increases the rate of degradation of biological particles. The essence of the invention is illustrated in Figure 1, which shows a technological scheme illustrating the process of wastewater treatment and decontamination. The method is implemented in three stages: mechanical cleaning, primary cleaning and decontamination, final cleaning and decontamination. Wastewater 1 is collected in the receiving tank 2 and enters the cleaning filters 3 where the waste is cleaned. After mechanical cleaning, the wastewater enters the tank 4 where the primary technological cleaning and decontamination takes place. The technological operation is carried out by a vibratory cavity 5, which is connected to the air valve 6. After the initial cleaning, the effluent settles and is pumped into the tank 8 by pump 7 and the sludge is pumped into the dryer by means of a pump 9. The re-discharge of wastewater into tank 4 and its treatment is continued. The waste water from the vibrating cavity 10 exposed to the container 8 is finally cleaned and pumped out by pump 12, and the remainder of the sludge pump 13 is fed to the dryer. Cavitators 5, 10 produce a hydrodynamic cavitation process with a cyclic flow of fluid (effluent) through the fixed length holes with pointed input and output edges. The holes are located on the piston in the tube with the closed bottom. The lower part of the pipe is connected via a tube with an air valve. By filling the tank in the tank, they pass through the holes in the pipe and pass through it to the bottom of the pipe. When the vibrating actuator is switched on, the plunger moves downwards and the waste water is forced out through the holes in the form of jets, and when the piston moves upwards, the downward direction of the jet changes and the air portion is fed into the tube through the valve which is controlled by the valve to shred it into small bubbles. Hydrocavitation occurs at the defined piston and hole rates and the oscillation process. Multiple wastewater leakage through the treatment zone by saturation with oxygen in the air increases the intensity of the sludge shredding, acidification at the same time and decontamination.

Studies with an experimental bench showed that after the treatment process, the amount of biological oxygen demand decreased 2.2 times and the acidity increased by 70%, and the decontamination of the bacteria decreased from 63 to 3.

Compared to the prototype, a new set of constructive elements, thanks to the introduction of multiple wastewater discharges through a cavitation unit with simultaneous porous (metered) air supply to the hydrocavitation zone, it is possible to achieve new technical properties and obtain a technical result - accelerated cleaning and decontamination of the wastewater. as a result, achieve new ways of applying the method to release non-hazardous waste into the environment.

Claims (1)

5 DEFINITION DEFINITION The method of wastewater treatment and decontamination, which combines periodic mechanical, biological treatment and decontamination, drainage and sediment removal, characterized in that the effluent is subjected to cyclic hydrocavitation with simultaneous dosing into a cavitation zone in the form of a bubble having dimensions of 0.2 or more. up to 0.4 millimeters.