A device and method for efficient oxidation of waste lye with fractal distribution of large and small bubbles

Abstract

The invention provides a device for high-efficiency oxidation of waste lye with fractal distribution of large and small bubbles. In the first burster, a liquid phase inlet is arranged at the bottom of the outer cylinder, a first gas distribution device for distributing the gas phase is arranged below the first burster, and a first gas phase inlet is arranged on the side of the outer cylinder to communicate with the first gas distribution device, The upper part of the outer cylinder is provided with a discharge port. The present invention also provides a method for oxidizing waste lye using the above-mentioned device. All equipment components of the present invention are large-sized channels, and are static components without flow dead zone, thus avoiding a large amount of potential scale deposits. The waste lye and compressed air are the kinetic energy sources, and the water in the upper cavity of the separator is a continuous phase fluid, which makes the temperature of the device more uniform. The device of the invention greatly improves the oxygen utilization rate and the oxygen mass transfer rate of the whole device, and the temperature of the cross section of the device is more uniform.

Description

technical field [0001] The invention belongs to the technical field of waste liquid treatment, and in particular relates to a device and method for efficient oxidation of waste alkali liquid with fractal distribution of large and small bubbles. Background technique [0002] Waste lye mainly contains sulfide, sodium carbonate, sodium hydroxide and refractory organics, and has strong odor, strong alkalinity and high toxicity. This lye cannot be directly discharged into the sewage treatment plant, and the air pollution is serious. [0003] At present, domestic and foreign waste lye treatment technologies include adsorption method, dissolution extraction method, chemical precipitation method, chemical oxidation method, composite catalytic oxidation method and air oxidation method. Adsorption method uses capillary porous substances (such as activated carbon, sulfonated coal, resin, etc.) to absorb toxic and harmful pollutants in waste lye, and remove harmful substances such as c...

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Problems solved by technology

[0040] indicated by S 2- Convert to S 2+ Relatively easy, by S 2- Convert to S 6+ It is difficult, in the traditional aerated oxidation reactor, the conversion rate of sodium sulfide to sodium sulfate is less than 25%

However, because the gas volume fraction of the dissolved air pump is too small, the gas volume fraction cannot be increased. It has been verified by experiments that the method and idea of ​​the dissolved air pump to improve the oxygen mass transfer and thereby improve the oxidation efficiency are incorrect.

[0045] Using pure oxygen aeration oxidation, the solubility of pure oxygen in water at normal temperature and pressure is only 42mg / L, a large amount of oxygen escapes, not only the cost is too high, but also the risk of explosion of organic matter and pure oxygen is greatly aggravated, and the increase of intake oxygen content cannot meet the requirements Requirements for safe operation

[0046] Microporous aeration is used to catalyze oxidation, and the aeration head with 20 micron pores is used. The size of the bubbles is controlled to be less than 1mm, but the total air intake of microporous aeration is very small, and the reaction needs to consume 320kg / h of oxygen. If the oxygen is effectively used 50%, you need 600kg / h of oxygen feed, about 2000m 3 / h gas flow, the calculation requires tens of thousands of microporous aeration heads, and the cost and installation space cannot be realized

In addition, once there are several large holes in the microporous aeration head, the gas will come out from the large holes.

The micropores are easily blocked, and ultrafiltration equipment must be installed at the gas-liquid feed. Once blocked, the entire reaction device must be shut down in an emergency

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