The present invention relates to a Fenton catalytic oxidation reactor and a method for treating difficult industrial wastewater thereof. The Fenton catalytic oxidation reactor comprises a reactor body, wherein a water inlet distribution pipe, an oxidant dosing pipe, a solid-phase catalyst layer and a spray device are sequentially arranged inside the reactor body from bottom to top. The water inlet distribution pipe is sequentially connected to an online pH meter, a pipeline mixer and a water inlet lifting pump through a wastewater inlet pipe, the oxidant dosing pipe is connected to an oxidant dosing pump, the spray device is connected to a flushing water inlet pipe, and a reactor outlet pipe and a reflux pipe are arranged from top to bottom between the solid-phase catalyst layer and the spray device, and the reflux pipe is connected to the wastewater inlet pipe through a reflux pump. Under the same water inlet conditions and the same dosing conditions, the pollutant removal rate of the reactor of the present invention is more than 30% higher than that of the Fenton fluidized bed; under the same removal rate, the dosing amount is 25%-40% less than that of the conventional Fenton reactor, and the chemical sludge output is more than 18% less.
The present invention provides a Fenton catalytic oxidation reactor and a method for treating difficult industrial wastewater thereof, which solves the problems of large amount of reagents used, large amount of sludge produced, high operating cost, etc. in the existing Fenton oxidation method for treating wastewater.
To solve the above technical problems, the technical scheme adopted by the present invention is as follows:
A Fenton catalytic oxidation reactor comprises a reactor body, wherein the reactor body is provided with a water inlet distribution pipe, an oxidant dosing pipe, a solid-phase catalyst layer and a spray device in sequence from bottom to top, wherein the water inlet distribution pipe is connected to an online pH meter, a pipeline mixer and a water inlet lifting pump in sequence through a wastewater inlet pipe, wherein a sulfuric acid inlet port and a ferrous sulfate inlet port are provided on the pipeline mixer, wherein the oxidant dosing pipe is connected to an oxidant dosing pump, wherein the spray device is connected to a flushing water inlet pipe, wherein a reactor outlet pipe and a reflux pipe are provided on the reactor body between the solid-phase catalyst layer and the spray device from top to bottom, wherein the reflux pipe is connected to the wastewater inlet pipe through a refluFurther, a preferred solution of the present invention is: the reactor body is a cylindrical structure with a raised head on the top.
Further, a preferred solution of the present invention is: the height-to-diameter ratio of the reactor body is 4-5.
Further, a preferred solution of the present invention is: the height of the solid-phase catalyst layer is 2.5-3 times the diameter of the reactor body.
Further, a preferred solution of the present invention is: the solid-phase catalyst layer uses a granular ceramic with a diameter of 10-20 mm as a carrier, which is sintered to attach a small amount of heavy metal ions, wherein the ceramic content is 95%, and the molar ratio of manganese, nickel, copper and iron is 0.02:0.03:5:10.
The present invention also provides a method for treating high-difficulty industrial wastewater, comprising the following steps:
(1) The high-difficulty industrial wastewater enters the water inlet distribution pipe at the bottom of the reactor body through the wastewater inlet pipe under the action of the water inlet lifting pump, sulfuric acid and ferrous sulfate enter the pipeline mixer to mix with the high-difficulty industrial wastewater, and flow out through the water distribution holes on the water inlet distribution pipe and flow upward in the reactor, and the wastewater inlet pH is controlled between 2.5-4 by an online pH meter, and the temperature is set at 20-35ºC;
(2) The oxidant is pumped into the oxidant dosing pipe through the oxidant dosing pump, and the oxidant flows out from the orifice of the oxidant dosing pipe and mixes with the wastewater flowing upward. After the oxidant and wastewater are mixed, they flow upward under the action of water flow and enter the solid phase catalyst layer;
(3) The oxidant and ferrous sulfate in the wastewater react under the action of the catalyst to strengthen the generation of hydroxyl radicals and other free radicals, triggering a variety of reactions, so that the macromolecular organic pollutant groups in the wastewater are destroyed, thereby forming small molecular substances or being directly mineralized into inorganic salts, and the pollutants in the wastewater are continuously degraded;
(4) The treated wastewater is mixed with the reactor inlet water through the reflux pipe and the reflux pump, so that the wastewater stays in the reactor body for 2-5 hours, and the wastewater treatment is completed. The treated wastewater can be discharged through the reactor outlet pipe;
(5) After the wastewater is discharged from the Fenton catalytic oxidation reactor, the pH value is adjusted to 6-7, and after the polyacrylamide flocculant is added and precipitated in the subsequent sedimentation tank, the supernatant achieves the treatment effect.
Further, a preferred embodiment of the present invention is: the oxidant uses 30% hydrogen peroxide.
Beneficial effects of the present invention:
The reactor of the present invention has been verified in the operation of the pilot reactor that under the same water inlet conditions and the same dosing conditions, the pollutant removal rate of the wastewater is more than 30% higher than that of the Fenton fluidized bed; under the same removal rate, the dosing amount is 25%-40% less than that of the Fenton fluidized bed, and the chemical sludge output is more than 18% less.
The solid-phase catalyst layer used in the present invention uses a granular ceramic with a diameter of 10-20mm as a carrier, which is attached with a small amount of heavy metal ions by sintering, wherein the ceramic content is 95%, and the molar ratio of manganese, nickel, copper and iron is 0.02:0.03:5:10. The oxidant and ferrous sulfate in the wastewater react under the action of the catalyst to strengthen the generation of hydroxyl radicals and other free radicals, triggering a variety of reactions, so that the macromolecular organic pollutant groups in the wastewater are destroyed, thereby forming small molecular substances or being directly mineralized into inorganic salts, with fast conversion and less consumption of reagents.
Since this reactor requires a certain upward flow rate, in order to prevent the weakening of mixing caused by uneven water volume, a reflux pipeline is added. The treated wastewater is mixed with the reactor inlet water through the reflux pipe and reflux pump to increase the upward flow rate. At the same time, some of the unreacted Fenton reagent in the wastewater after the reaction can continue to participate in the reaction, reducing the dosage of ferr
){kind=link}