CN106517686A - Coal tar wastewater treatment method - Google Patents

Abstract

The invention discloses a coal tar wastewater treatment method. The method includes procedures of CO2 pressurizing, iron powder reduction, anaerobic, aerobiotic and biological filter tower treatment and the like. Wastewater treated according to the method can stably reach standards for discharge.

Description

The processing method of Coal Tar Wastewater

Technical field

The present invention relates to a kind of processing method of the waste water of coal tar processing and storage process generation.

Background technology

Coal tar is one of important source material of production of chemicals, the Pollutants in Wastewater that its processing and storage process are produced COD concentration is high, complicated component, and toxicity is big, and contains a large amount of persistence organic pollutants（Containing phenyl ring and（Or）Heterocycle etc. it is organic Thing）, intractability is big.If the waste water is not processed is directly discharged into environment, severe contamination will be caused to environment.Current Coal Tar Wastewater Processing method mainly have burning method and biological treatment.Burning method processing cost is high, and produces atmospheric pollution.Biological treatment Method needs first to carry out advanced oxidation（Such as iron-carbon micro-electrolysis, metal powder reduction, Fenton methods etc.）Pretreatment, then carries out a biological disposal upon. In advanced oxidation preprocessing process, need to add sulphuric acid, cause subsequent biological treatment（Such as anaerobism, hydrolysis acidification）During produce Raw H₂S, produces more serious secondary pollution；Simultaneously because SO₄ ^2-Growth to microorganism has obvious inhibitory action, affects life Thing treatment effect, waste water are difficult to stably reaching standard discharge.Exploitation secondary pollution is little, processing cost is low, the coal of energy stably reaching standard discharge The processing method of tar and waste water has larger practical value.

The content of the invention

For the problem of current Coal Tar Wastewater processing method, the purpose of the present invention is that searching secondary pollution is little, can stablize The processing method of the Coal Tar Wastewater of qualified discharge, it is characterised in that the Coal Tar Wastewater after adjusted pond is adjusted is sent into pressure Cleaning iron powder is added reactor, and is passed through industrial CO by reactor₂Reacted, the granularity of iron powder is less than 180 mesh, and per liter is given up Water adds iron powder 10g～50g, and the stirring reaction time is 1h～3h, and reaction temperature is 25 DEG C～60 DEG C, CO₂Pressure be 0.1MPa～1.0MPa.Reacted waste water carries out solid-liquor separation, the iron powder Returning reactor isolated.It is useless after solid-liquor separation Water lime cream or other alkaline matters adjust its pH value to 6.8～8.5, precipitate 1h～3h subsequently into sedimentation tank, irregularly Extract sludge from sedimentation tank out to be filtered, filter cake makees dangerous disposition of solid waste, filtrate returns sedimentation tank.Sedimentation tank it is upper Stripping water send anaerobic reactor.Waste water stops 24h～120h in anaerobic reactor, and anaerobism temperature is 25 DEG C～55 DEG C.Anaerobism Into the process of biology aerobic pond room temperature, the Aerobic Process for Treatment time is 8h～16h to waste water afterwards.Waste water after Aerobic Process for Treatment enters precipitation 1h～3h is precipitated in pond, is irregularly extracted sludge out from sedimentation tank and is filtered, and filter cake makees dangerous disposition of solid waste, and filtrate is returned Return Aerobic Pond.The supernatant waste water of sedimentation tank send multi-layer biological filter tower to process.The filler of biological filtering tower combined working is activated carbon or porous ceramic grain, It is 1.0m～2.0m per thickness degree, gross thickness is 2m～6m.The dominant bacteria of biological filtering tower combined working is the red false unit cell in photosynthetic bacteria Bacterium（Rhodopseudomonas）.The hydraulic load of biological filtering tower combined working is 30 m³/m².d～90m³/m².d.The water outlet of biological filtering tower combined working Qualified discharge or reuse.

The object of the present invention is achieved like this, after Coal Tar Wastewater enters iron powder reducing reactor, big point in waste water Sub- Organic substance, particularly persistence organic pollutant（Containing phenyl ring and（Or）The Organic substance of heterocycle etc.）Produced by iron powder reducing Reduce the effect of free radical by force and destroy, be that subsequent biochemical process creates favorable conditions.It is passed through pressure CO₂Purpose be maintain ferrum Powder reduces suitable pH value（2.0～5.0）, the waste water lime cream or other alkaline matters after reduction adjusts its pH value, with full The requirement of the follow-up anaerobic and aerobic process of foot.The premenstrual waste water for stating process is in anaerobic processes, by the effect of microorganism, big to divide Sub- Organic substance further becomes small organic molecule, is that more favorable condition is created in subsequent bio oxidation.By biological oxidation process, Remaining most of Organic substances are removed, while the pollutant such as removing to denitrogenate.Waste water finally enters activated carbon or porous ceramic grain is biological Filter tower, in the presence of microorganism, particularly rhodopseudomonas, the pollutant such as further organics removal and nitrogen, it is ensured that process Waste water stably reaching standard discharge afterwards.

Relative to existing method（Iron-carbon micro-electrolysis, metal powder reduction, Fenton methods etc.）, the outstanding advantages of the present invention are to adopt Use CO₂Replace now widely used sulphuric acid to make acidulant, do not introduce SO₄ ^2-Ion, essentially eliminates generation H₂The material base of S （Coal Tar Wastewater contains a small amount of S）, so as to significantly reduce H₂The pollution of S, while it also avoid SO₄ ^2-To anaerobic and aerobic mistake The inhibitory action of microorganism in journey, greatly improves the efficiency of biological treatment；Burner, fuel combustion are all had in coal tar processing factory Burn the CO for producing₂Waste gas can make full use of, and can not only reduce processing cost, and can reduce carbon emission；Waste water after process Energy stably reaching standard discharge, with obvious economic benefit and environmental benefit.

Specific implementation method

Embodiment 1：Day processes 1 cubic metre of Coal Tar Wastewater（Volatile phenol 2400mg/L, COD15500mg/L, CN^-25.5mg/L、 NH₃-N57mg/L）, Jing iron powder reducings（1h、40℃、CO₂Pressure 0.6MPa, every liter of waste water add iron powder 40g）, anaerobism（pH8.5、 72h, 25 DEG C～35 DEG C）, it is aerobic（12h）And biological filtering tower combined working（Porous ceramic grain packing layer gross thickness 4m, hydraulic load 35m³/m².d） After process, the pollutant levels of water outlet are respectively COD_Cr 76mg/L、NH₃- N 5.3mg/L, volatile phenol 0.4mg/L, CN^- 0.12mg/L。

Embodiment 2：Day processes 3 cubic metres of Coal Tar Wastewaters（Volatile phenol 920mg/L, COD8700mg/L, CN^-17mg/L、 NH₃-N48mg/L）, Jing iron powder reducings（3h、25℃、CO₂Pressure 0.1MPa, every liter of waste water add iron powder 10g）, anaerobism（pH6.8、 24h, 35 DEG C～55 DEG C）, it is aerobic（8h）And biological filtering tower combined working（Active carbon filler layer gross thickness 2m, hydraulic load 90m³/m².d）Process The pollutant levels of water outlet are respectively COD afterwards_Cr 58mg/L、NH₃- N 4.7mg/L, volatile phenol 0.3mg/L, CN^-0.09mg/L。

Claims (1)

1. a kind of processing method of Coal Tar Wastewater, it is characterised in that will adjusted pond adjust after Coal Tar Wastewater send into it is resistance to Cleaning iron powder is added reactor, and is passed through industrial CO by pressure reactor₂Reacted, the granularity of iron powder is less than 180 mesh, per liter Waste water adds iron powder 10g～50g, and the stirring reaction time is 1h～3h, and reaction temperature is 25 DEG C～60 DEG C, CO₂Pressure be 0.1MPa～1.0MPa, reacted waste water carry out solid-liquor separation, the iron powder Returning reactor isolated, useless after solid-liquor separation Water lime cream or other alkaline matters adjust its pH value to 6.8～8.5, precipitate 1h～3h subsequently into sedimentation tank, irregularly Extract sludge from sedimentation tank out to be filtered, filter cake makees dangerous disposition of solid waste, filtrate returns sedimentation tank, sedimentation tank it is upper Stripping water send anaerobic reactor, waste water that 24h～120h is stopped in anaerobic reactor, and anaerobism temperature is 25 DEG C～55 DEG C, anaerobism Waste water afterwards is 8h～16h into the process of biology aerobic pond room temperature, Aerobic Process for Treatment time, and the waste water after Aerobic Process for Treatment enters precipitation 1h～3h is precipitated in pond, is irregularly extracted sludge out from sedimentation tank and is filtered, and filter cake makees dangerous disposition of solid waste, and filtrate is returned Aerobic Pond is returned, the supernatant waste water of sedimentation tank send multi-layer biological filter tower to process, the filler of biological filtering tower combined working is activated carbon or porous ceramic grain, Filler gross thickness is 2m～6m, and the dominant bacteria of biological filtering tower combined working is the rhodopseudomonas in photosynthetic bacteria, the waterpower of biological filtering tower combined working Load is 30 m³/m².d～90m³/m².d, the standard water discharge discharge or reuse of biological filtering tower combined working.