Fenton-like reactor and toxic and refractory wastewater treatment device and treatment method

Abstract

The invention provides a Fenton-like reactor which comprises a reaction tank, a reflux tank, a reflux pipe, a reflux pump and a cambered elbow, wherein the reaction tank is filled with a micron-sized microelectrolysis filler and provided with an aeration part and a stirrer; the reaction tank is provided with a to-be-treated wastewater inlet, a water outlet, a dosing port and at least three circulating water inlets; the circulating water inlets are arranged around the reaction tank; one end of the reflux pipe is connected with a circulating water outlet of the reflux tank, and the other end is respectively connected with the circulating water inlets of the reaction tank through branch pipes; the reflux pump is connected with the reflux pipe; one end of the cambered elbow is connected with the water outlet of the reaction tank; and the opening on the other end is upward and is connected with the water inlet of the reflux tank through a pipe fitting. The toxic nondegradable wastewater treatment device is formed by sequentially connecting a first Fenton-like reactor set, a Fenton reactor, a second Fenton-like reactor set and 2-4 stages of coagulative precipitation tanks in series. The invention also provides a method for treating wastewater by using the toxic nondegradable wastewater treatment device.

Description

technical field [0001] The invention belongs to the field of toxic and refractory wastewater treatment, and in particular relates to a Fenton-like reactor, a device for treating toxic and refractory wastewater and a method for treating toxic and refractory wastewater. Background technique [0002] At present, toxic and refractory wastewater mainly uses Fenton-like and Fenton reactions for physical and chemical pretreatment. The Fenton-like reaction refers to the reaction of zero-valent iron and iron-based multimetallic materials with oxygen 2 Reduction to generate H 2 o 2 , then at Fe 2+ Under the catalysis of catalysis, strong oxidizing hydroxyl radicals (OH) are generated in situ, and the reaction equations are shown in formulas (1)-(2); Fenton reaction refers to H 2 o 2 in Fe 2+ Under the catalytic action of , strong oxidizing OH is produced, and the reaction equation is shown in formula (3). The OH produced during the Fenton-like and Fenton reactions can non-selec...

AI Technical Summary

Problems solved by technology

But this type of device still has the following disadvantages: (1) the energy consumption required to rotate the reactor or the packing drum is high, resulting in high operating costs; (2) although the rotation can make the packing turn over, it cannot make the packing roll over the entire reactor. The interior is in a fully fluidized state, and the mass transfer efficiency is limited, which is not conducive to the improvement of wastewater treatment efficiency.

Although this method combines the advantages of micro-electrolysis and Fenton oxidation, there are still the following problems: (1) Since Fenton oxidation is carried out under the condition of pH=3, its effluent is also acidic, and the pH of Fenton oxidation effluent is usually The value is about 3, and a large amount of alkali must be added for neutralization during subsequent coagulation and precipitation. This method not only wastes alkali but also wastes acid, resulting in high treatment costs; (2) unreacted Hydrogen peroxide, when hydrogen peroxide enters the subsequent biochemical treatment unit, it will have a strong inhibitory effect on microorganisms and affect the biological treatment effect. Therefore, it is necessary to install a hydrogen peroxide removal device after the Fenton oxidation process, which not only leads to an increase in equipment investment, but also causes hydrogen peroxide. waste, which further increases the cost of wastewater treatment; (3) Iron filings and activated carbon are fixedly filled in the micro-electrolytic column, and the fixed filling will seriously affect the interaction between pollutants, corrosion products, active substances, and degradation products between the liquid phase and the surface of the filler. The mass transfer efficiency leads to the low efficiency of the micro-electrolytic column for wastewater treatment, and the fixed filling will easily lead to the passivation of the packing, resulting in a gradual decrease in treatment efficiency, which is not conducive to the long-term normal operation of the micro-electrolytic column

Images