CN102718345A - Method for utilizing coke powder to deeply treat COD (Chemical Oxygen Demand) and chrominance of coking wastewater - Google Patents

Abstract

The invention discloses a method for utilizing coke powder to deeply treat COD (Chemical Oxygen Demand) and chrominance of coking wastewater. The whole process has the following steps: output water of a biochemical system sequentially flows into a water storage pool, a coke powder adsorption reaction tank, a coke adsorption settling pond, a high-grade oxidization reaction tank and a high-grade oxidization settling pond; and finally, output water reaches the standard and is discharged out. The method comprises the specific implementation steps of: a, adding coke powder into the front end of the coke powder adsorption reaction tank to perform adsorption reaction; b, conveying a mixed solution from the step a into the coke powder adsorption reaction tank to perform mud-water separation; c, conveying liquid supernatant separated from the step b into the high-grade oxidization reaction tank and adding a mixed flocculating agent to remove the COD and the chrominance; and d, conveying the mixed solution from the step c into the high-grade oxidization settling pond to perform the mud-water separation; conveying separated liquid supernatant into a clean water basin and discharging the clean water after reaching to the standard; and conveying sludge into a sludge concentration tank. With the adoption of the method, the chrominance of the coking wastewater can be controlled to be lower than 20 times; and the COD is controlled to be below 100mg/L and the GB8978-1996 national first level discharge standard is achieved.

Description

A kind of method of utilizing coke powder advanced treatment on coking wastewater COD and colourity

Technical field

The invention belongs to biochemical environmental technology field, particularly relate to the method for utilizing coke powder advanced treatment on coking wastewater COD and colourity with a kind of.

Background technology

The coke powder that smelting iron and steel enterprise coking is produced, general remove be used in a large number smelting iron and non-ferrous metal metallurgy (metallurgical coke), also as reductive agent and fuel be used in a large number to cast, the sintering process of chemical industry, calcium carbide and iron alloy, iron ore.

Coking chemical waste water is the waste water that in the former dry distillation of coal, gas purification and Chemicals treating process, produces; Not only quantity discharged is big; Wherein also contain a large amount of pollutents; And complicated component, the inorganics that wherein contains comprises a large amount of ammonium salts, thiocyanide, sulfide, prussiate etc., organism mainly is heterocycle macromole, difficult degradation compounds such as aromatics, phenols and verivate thereof and pyridine, quinoline, anthracene.Present domestic coking chemical waste water adopts materialization or biochemical processing process basically; Single biochemical treatment can only be satisfied phenol, cyanogen, the requirement of ammonia nitrogen qualified discharge; Index such as COD, colourity is difficult to reach " integrated wastewater discharge standard " first discharge standard requirement (GB8978-1996); And materialization is handled because will add medicament, and cost is often higher.Require and the Treatment of Coking Effluent present situation according to GB8978-1996, realize comprehensive qualified discharge of principal pollutant, must carry out further advanced treatment the waste water after the biochemical treatment.

At present, the advanced treatment of coking chemical waste water mainly adopts active carbon adsorption, ozone oxidation method and strong oxidizer oxidation style both at home and abroad.Baosteel was once introduced its coking biochemical waste water of charcoal absorption method of reproduction advanced treatment of Japan; But price comparison costliness because of gac itself; The regeneration of activated carbon treating processes produces regenerated sewage, problem such as the regenerative operation difficulty is big, running cost height and cause device finally to be stopped using.External place of adopting the ozone oxidation method exists that current consumption is big, operation and investment cost be high, and misoperation is prone to problems such as biology on every side work the mischief.The strong oxidizer oxidation style also exists medicament expense with high shortcoming.The waste water advanced New Method for Processing of some coking biochemicals of domestic invention exploitation also respectively has its advantage and deficiency; Like of the processing of catalysis and supercritical water oxidation technology, though effect significantly exists equipment corrosion, reactor plugs, running cost to cross problems such as height to coking chemical waste water; Microwave radiation-charcoal absorption advanced treatment on coking wastewater method, same because problems such as technology maturation property and running cost height realize that industriallization also has big difficulty.

Summary of the invention

The purpose of this invention is to provide a kind of method, to solve the difficult problem that index such as COD and colourity after the present Treatment of Coking Effluent is difficult to reach integrated wastewater discharge standard with coke powder advanced treatment on coking wastewater COD and colourity.

For this reason; The present invention adopts following technical scheme: a kind of method of utilizing coke powder advanced treatment on coking wastewater COD and colourity; On integrated artistic, done following layout: the biochemical system water outlet flows into water reservoir, coke powder absorption reaction pond, coke powder adsorption precipitation pond, advanced oxidation reaction tank, advanced oxidation settling tank, final outflow water standard discharge successively; The practical implementation step is following:

A, front end adds coke powder in coke powder absorption reaction pond, in coke powder absorption reaction pond, mixes with the biochemical system water outlet, carries out absorption reaction;

B, the mixed solution in a step is sent into coke powder adsorption precipitation pond deposition, carry out mud-water separation; Supernatant is sent into the advanced oxidation reaction tank, and deposition is sent into the storage slag bath;

C, the supernatant that step b is separated are sent into the advanced oxidation reaction tank, through adding the mixed flocculation agent, further remove COD, colourity etc.;

D, the mixed solution among the step c is sent into advanced oxidation settling tank deposition, carry out mud-water separation, the supernatant after the separation gets into the clean water basin standard discharge, and mud is delivered to sludge thickener.

Further, in step a, the bulk density that adds coke powder is 0.5 ~ 0.7g/ml, and dosage is 1.5 ~ 5% (mass and size per-cents) of flooding quantity; Through whipping appts in the coke powder absorption reaction pond and biochemical system water outlet uniform mixing.

Further, mixed solution is the continous way Inlet and outlet water in step a, keeps flowing.

Further, the flocculation agent that in step c, adds is HL-9705A, HL-9705B, and dosage is respectively 600ppm, 300ppm.

The present invention utilizes the adsorption property of the similar gac of coke powder physical and chemical performance; Water outlet is handled to coking wastewater biochemical system, after mixing, and the concentration stabilize in water; Keep good seed activity and bigger granule surface area, well the adsorption treatment coking chemical waste water.

Step a adopts the continous way Inlet and outlet water, and making the waterpower fluidised form collection mixing in coke powder absorption reaction pond is one with plug-flow, thereby coke powder is in suspended state all the time in the maintenance adsorption tank, prolongs the active adsorption time, avoids the premature deposit of coke powder.

After adopting the present invention, can coking chemical waste water colourity be controlled at below 20 times, COD is controlled at below the 100mg/L, reaches that GB8978-1996 is country-level to go out water quality standard.

Description of drawings

Below in conjunction with the present invention being done further explain with accompanying drawing.

Fig. 1 is a process flow sheet of the present invention.

Annotate: A: biochemical system water outlet; B: flocculation agent HL-9705A, HL-9705B; C: water outlet.

Embodiment

Present embodiment is the test run(s) that the present invention is done in certain waste water treatment engineering, and this test is blocking test, and nonspecific crowd can not contact, understand process of the test.

As shown in Figure 1, the present invention has spatially constituted four main unit with coke powder absorption reaction pond, coke powder adsorption precipitation pond, advanced oxidation reaction tank, advanced oxidation settling tank.Coking chemical waste water is introduced into water reservoir before in coke powder absorption reaction pond, waste residue gets into the storage slag bath behind coke powder adsorption precipitation pond, behind the storage slag bath, gets into reclamation set, is recycled to the coke powder throwing device.Waste water through coke powder adsorption precipitation pond can flow into the advanced oxidation reaction tank, and waste residue can get into the storage slag bath through the solid-liquid part flow arrangement.The practical implementation step is following:

A, with the terminal biochemical waste water of coke-oven plant's biochemical treatment as the biochemical system water outlet, promote and after the under meter metering, send in the coke powder absorption reaction pond through the force (forcing) pump pressurization; The basic physical behavior of used coke powder is an ash content 35.35% in this technology operational process, fixed carbon 56.16%, moisture 1.87%, mean particle size 55.0 orders, pore volume rate 0.570m³/ m³, specific surface 40.8m²/ g, bulk density are 0.5 ~ 0.7g/ml.Coke powder is added into the coke powder adsorption tank through worm conveyor; 1.5 ~ 5% (mass and size per-cents) by coking chemical waste water feed intake to coke powder, under the effect of whipping appts, mix fully.

The mixed solution of b, step a flows automatically in the adsorption precipitation pond, leans on the action of gravity of current to realize separating.Supernatant after the filtering separation flows to clean water basin through gravity flow, directly standard discharge or be for further processing.The filter residue of post precipitation gets into the storage slag bath through the solid-liquid part flow arrangement, recycles or further processing treatment.

C, with the waste water that needs among the step b further to handle with being pumped into the advanced oxidation reaction tank, add flocculation agent HL-9705A, HL-9705B, the dosage of flocculation agent is respectively 600ppm, 300ppm.

D, again the waste water of step c is sent into the advanced oxidation settling tank, lean on the current action of gravity to carry out mud-water separation, the supernatant after the separation gets into the clean water basin standard discharge, and mud carries out the mud concentration with being pumped to sludge thickener.

Can be among e, the step b according to practical situation; The filter residue that needs further to handle carries out coke powder processing through reclamation set; The filter residue that to handle is afterwards sent into the coke powder throwing device and is utilized once more, adsorbs saturated coke powder and also can be processed as power boiler fuel and be used.

Pass through the reactor drum of successive type Inlet and outlet water in the coke powder absorption reaction pond of step a; The thorough mixing of water inlet of realization system and coke powder; Efficiently absorption is that collection mixes and plug-flow is the dynamic adsorption equipment of one on the waterpower fluidised form, and coke powder is in suspended state all the time in the maintenance adsorption tank; Prolong adsorption time, avoided the coke powder premature precipitation.In the steps d through add HL-9705A, the HL-9705B flocculation agent is handled waste water further, the COD of gained water outlet is stabilized in below 60 mg/L, clearance is higher than 80%, effluent color dilution reaches 5 ~ 15 times.System's effluent index, especially COD and colourity after the coke powder absorption are far superior to conventional treatment process, see the following form.

After adopting the present invention, can coking chemical waste water colourity be controlled at below 20 times, COD is controlled at below the 100mg/L, reaches that GB8978-1996 is country-level to go out water quality standard.Simultaneously, the present invention can reduce the dosage of medicament, through measuring and calculating, handles adding expenses for medicine and can reducing to 0.64 yuan from original 1.635 yuan of one ton of waste water, practices thrift 0.995 yuan of/ton water of cost, and processing cost reduces by 60.86%.Adsorb saturated coke powder after dehydration, can also be used as power boiler fuel.It is thus clear that the present invention has maximally utilised coke powder, turn waste into wealth, demonstrated fully the spirit of the treatment of wastes with processes of wastes against one another.

Claims (4)

1. method of utilizing coke powder advanced treatment on coking wastewater COD and colourity; On integrated artistic, done following layout: the biochemical system water outlet flows into water reservoir, coke powder absorption reaction pond, coke powder adsorption precipitation pond, advanced oxidation reaction tank, advanced oxidation settling tank, final outflow water standard discharge successively; It is characterized in that: the practical implementation step is following:

A, front end adds coke powder in coke powder absorption reaction pond, in coke powder absorption reaction pond, mixes with the biochemical system water outlet, carries out absorption reaction;

B, the mixed solution in a step is sent into coke powder adsorption precipitation pond deposition, carry out mud-water separation; Supernatant is sent into the advanced oxidation reaction tank, and deposition is sent into the storage slag bath;

C, the supernatant that step b is separated are sent into the advanced oxidation reaction tank, through adding the mixed flocculation agent, further remove COD, colourity etc.;

D, the mixed solution among the step c is sent into advanced oxidation settling tank deposition, carry out mud-water separation, the supernatant after the separation gets into the clean water basin standard discharge, and mud is delivered to sludge thickener.

2. according to the described a kind of method of utilizing coke powder advanced treatment on coking wastewater COD and colourity of claim 1, it is characterized in that: in step a, the bulk density that adds coke powder is 0.5 ~ 0.7g/ml, and dosage is 1.5 ~ 5% (mass and size per-cents) of flooding quantity; Through whipping appts in the coke powder absorption reaction pond and biochemical system water outlet uniform mixing.

3. according to claim 1 or 2 described a kind of methods of utilizing coke powder advanced treatment on coking wastewater COD and colourity, it is characterized in that: mixed solution is the continous way Inlet and outlet water in step a, keeps flowing.

4. according to the described a kind of method of utilizing coke powder advanced treatment on coking wastewater COD and colourity of claim 1, it is characterized in that: the flocculation agent that in step c, adds is HL-9705A, HL-9705B, and dosage is respectively 600ppm, 300ppm.

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