CN103145266A

CN103145266A - Method for treating coking wastewater by using ozone under catalysis of activated carbon

Info

Publication number: CN103145266A
Application number: CN2013100888615A
Authority: CN
Inventors: 万哲希; 丁国际; 周惟斌; 沈海桦; 陈斯芝; 张晶
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2013-03-20
Filing date: 2013-03-20
Publication date: 2013-06-12

Abstract

The invention provides a method for treating coking wastewater by using ozone under catalysis of activated carbon. The method comprises the following steps of: continuously leading coking wastewater into a catalytic reactor in which activated carbon particles are fed in advance, continuously introducing ozone into the reactor from the bottom of the reactor so that the coking wastewater, activated carbon and ozone have reaction completely; enabling the treated waste water to flow into a settling tank, separating treated effluent water from activated carbon flowing out together with water, feeding the separated activated carbon into the reactor again through a pump, leading the effluent water to the following biological treatment technique. The COD removal rate of the coking wastewater treated by adopting the method is more than 60%, the removal rate of volatile phenol can is more than 90%, and the chromacity is obviously removed.

Description

A kind of method of activated carbon catalysis ozonize coking chemical waste water

Technical field

The present invention relates to the Persistent organic pollutants in a kind of ozone catalytic oxidation water processing method, particularly Treatment of Wastewater in Coking.

Background technology

Coking chemical waste water adopts merely treating coking wastewater biologically owing to wherein containing a large amount of hardly degraded organic substances, and the effluent quality index often is difficult to reach discharging standards.In recent years, Ozonation more and more is applied in the processing of trade effluent as a kind of high-level oxidation technology.But, because ozone solubleness in water is lower, make oxidation efficiency lower; And because the direct oxidation of ozone often can not make hardly degraded organic substance be decomposed into carbonic acid gas fully, and may there be toxicity in the intermediate oxidation product that produces, and this makes the effect of Ozonation be restricted.It should be noted, the oxidation capacity of hydroxyl radical free radical is stronger than ozone, most organic pollutants effectively can be decomposed even thoroughly mineralising, and ozone also can produce some hydroxyl oxidize agent in oxidising process.The main points of the new technologies such as the ozone/ultrasonic wave that comes into one's own at present, ozone/UV, ozone and active carbon are exactly take ozone as basic oxygenant, promote the ozone generation hydroxyl radical free radical with materialization means such as ultrasonic wave.

Ozone and active carbon is to utilize gac to have flourishing gap structure, huge specific surface area and surperficial nonpolar chemical property, plays the effect of adsorb organic compound and O3 catalytic oxidation.Ozone and active carbon is compared with novel procesies such as ozone/UV, because equipment is simple, with low cost, more receives publicity, and can consider to be applied to Treatment of Coking Effluent.

Summary of the invention

The method that the purpose of this invention is to provide a kind of using ozone/catalystic oxidation activated carbon method Treatment of Wastewater in Coking; use granulated active carbon as catalyzer, O3 catalytic oxidation coking chemical waste water; to reach the removal hardly degraded organic substance, reduce the concentration of hazardous and noxious substances in coking chemical waste water.

For achieving the above object, the technical solution used in the present invention is to provide a kind for the treatment of process of coking chemical waste water, its method is mainly to pass into continuously coking chemical waste water in the closed reactor that adds in advance gac, and pass into ozone at reactor bottom, make ozone, gac and the abundant contact reacts of coking chemical waste water three.Waste water after processing enters settling tank, and gac is separated with processed waste water, and after processing, water can enter subsequent biological treatment technique.The gac that separates can be collected, and reenters reactor and uses.

The gac that uses in above-mentioned steps is granulated active carbon, has larger specific surface area, and its catalytic capability makes ozone improve 20% left and right to the degradation rate of COD in coking chemical waste water, and the degradation rate of volatile phenol also is increased.The effect of granulated active carbon on the one hand can adsorb organic compound, reduces the organic loading that reactor is born, and can produce hydroxyl radical free radical by catalysis ozone on the other hand, improves the organic ability of ozone oxidation.

In above-mentioned steps, but the gac life-time service in reactor.

Effect of the present invention is that the method can reach the COD value clearance of coking chemical waste water more than 60%, and the clearance of volatile phenol reaches more than 90%, the full wavelength scanner discovery, and the characteristic peak of toxic substance disappears, and illustrates that toxic substance is fully degraded.

Description of drawings

Fig. 1 is the volatile phenol clearance comparison diagram of the independent oxidation of ozone and ozone/seed activity char combustion.

Fig. 2 is the COD clearance comparison diagram of the independent oxidation of ozone and ozone/seed activity char combustion.

Fig. 3 is the uv-vis spectra comparison diagram of the independent oxidation of ozone and ozone/seed activity char combustion.

Embodiment

In conjunction with the embodiments the treatment process of coking chemical waste water of the present invention is illustrated.

1, the COD concentration of pending coking chemical waste water is 800 ~ 1000mg/L, and volatile phenol concentration is 15 ~ 25mg/L.The closed reactor volume that adopts is 10L, adds in advance the gac of 200g left and right;

2, before coking chemical waste water enters reactor, regulate its pH to 8 ~ 10;

3, coking chemical waste water enters reactor in the Continuous Flow mode, and the coking chemical waste water flow maintains the 10L/h left and right;

4, after coking chemical waste water enters reactor, pass into ozone at reactor bottom, it is 3g/h that adjusting ozone adds concentration, makes ozone fully contact with gac with waste water;

5, the reactor water outlet enters settling tank, and the gac that flows into water precipitates in settling tank, the discharging of settling tank supernatant liquor.

By processing, the COD clearance of coking chemical waste water reaches more than 60%, and concentration is about 200mg/L, and the volatile phenol clearance is more than 90%, and organism such as quinoline, indoles etc. that other are complicated are all decomposed, and can not produce too much influence to follow-up bioprocess technology.Before processing, waste water is red-brown, is faint yellow after processing, and color removal is obvious.

Claims

1. the method for an activated carbon catalysis ozonize coking chemical waste water, its method comprises the following steps:

1) with coking chemical waste water pH regulator to 8 ~ 10;

2) coking chemical waste water after adjusting pH flows in the catalyticreactor of sealing, and whole process adopts continuous water-inlet continuous water-outlet;

3) add in advance the gac that particle diameter is 0.25 ~ 2mm in reactor, the gac dosage is determined by reactor volume;

4) after the coking chemical waste water inflow reactor, pass into ozone at reactor bottom, ozone dosage is 3g/h, and its saturated solubleness in water is about 3mg/L;

5) coking chemical waste water enters settling tank in reactor for treatment after for some time;

6) in settling tank, from the gac precipitation that reactor flows into water, the discharging of settling tank supernatant liquor, the gac of precipitation is accumulated to a certain amount of rear use and is pumped into reactor.

2. treatment process according to claim 1, it is characterized in that: ozone is produced by high frequency ozone generator.

3. treatment process according to claim 1, it is characterized in that: coking chemical waste water residence time in reactor gets between 30 ~ 60min according to waste water quality and water quality treatment target.

4. treatment process according to claim 1 is characterized in that: discharge supernatant liquor and can enter follow-up bioprocess technology and further process in step 6, to improve the effluent quality effect.