CN101264994A - Process for treating deposition vanadium mother liquid - Google Patents

Abstract

The invention relates to a method for treating vanadium sedimentation mother liquid, comprising the following steps of: adding FeSO4*7H2O into vanadium sedimentation mother liquid with a mass ratio of mFeSO4:mCr=(30-40):1, and reacting for 2-5 min; adjusting pH to 7-8 with CaO emulsion, reacting for 20-30 min, and performing solid-liquid separation to obtain filtrate and filter cake; adjusting pH of the filtrate to 8.5-10 with NaOH solution, keeping the pH at 8.5-10, blowing off ammonia gas in the solution by air stripping method, crystallizing the stripped ammonia gas with acidic spraying liquid to obtain ammonium salt, and recycling to ammonium salt vanadium sedimentation process; adjusting the pH of the filtrate after ammonium separation to 9.5-10.5 with CaO emulsion, reacting for 10-15 min, adjusting pH to 10.5-12 with CaO emulsion, reacting for 10-15 min, and performing solid-liquid separation to obtain basic treated liquid. The inventive method has the advantages of comprehensive utilization of wastewater, good adaptability, convenient process operation, short treatment period, no secondary pollution, and good treatment effect.

Description

A kind of treatment process of deposition vanadium mother liquid

Technical field

The invention belongs to the Industrial Wastewater Treatment field.Relate in particular to a kind of treatment process of deposition vanadium mother liquid.

Background technology

Because the fast development of vanadium industry, the wet method vanadium extraction is outstanding day by day to the effect of vanadium industry, and wet method extracting vanadium and precipating vanadium operation adopts the ammonium salt precipitation more, and vanadium is prepared into the ammonium salt of vanadium, by the ammonium salt of vanadium is further handled needed vanadium compound.The ammonium salt precipitation mainly according to the difference of precipitation pH, is divided into the precipitation of weakly alkaline ammonium salt, the precipitation of slightly acidic ammonium salt and acid ammonium salt precipitation, V in the corresponding deposition vanadium mother liquid with the ammonium salt precipitation ₂O ₅Content generally is respectively 1～2.5g/L, 0.05～0.5/L and 0.01～0.25g/L, and ammonia nitrogen concentration is far above general ammonia nitrogen in high density (NH ₄ ⁺＞500mg/L) waste water, and also contain in the deposition vanadium mother liquid other hazardous and noxious substances (" non-ferrous extractive metallurgy handbook editorial board. " under the rare refractory metal of non-ferrous extractive metallurgy handbook, Beijing: metallurgical industry press, 1999:338-342).

At present, the processing for deposition vanadium mother liquid mainly concentrates on removal heavy metal vanadium, chromium and two aspects of processing high-concentration ammonia nitrogenous wastewater.Do not reach wastewater discharge standard for removing direct processing of employing lime methods such as heavy metal vanadium, chromium in the deposition vanadium mother liquid, need additive method and lime method combination treatment usually; The method of handling ammonia nitrogen waste water both at home and abroad then mainly contains break point chlorination, selectivity ion exchange method, biological process and chemical precipitation method etc.

The first less investment of break point chlorination, but the working cost height, by product chloramines and chlorinatedorganic can cause secondary pollution, only are suitable for handling low-concentration ammonia-nitrogen waste water, and it is industrial in order to overcome the shortcoming of a large amount of chlorinations of independent employing break point chlorination processing ammonia nitrogen waste water needs, often with itself and biological nitration coupling, earlier the nitrated ammonia nitrogen of eliminating minute again (Xu Guoqiang, Ceng Guang is bright, Yin Zhiwei etc. ammonia nitrogenous wastewater treatment technology present situation and development. the Hunan non-ferrous metal, 2002,18 (2): 29-30), complex technical process.

The selectivity ion exchange method has that technology is simple, less investment, characteristics that clearance is high, the ammonia nitrogen waste water (NH of lower concentration in being applicable to ₄ ⁺＜500mg/L), but the ammonia nitrogen waste water for high density can frequently cause operational difficulty because of resin regeneration, and regenerated liquid be high-concentration ammonia nitrogenous wastewater (Li Guofeng. the removal of ammonia nitrogen waste water in the waste water. master thesis. Daqing Petroleum Institute 2005:5), still needs further to handle.

Biological rule mainly is converted into nitric nitrogen by nitration reaction with ammonia nitrogen, become gaseous nitrogen from water, to overflow nitrate-nitrogen reduction by anti-nitration reaction again, thereby reach denitrogenation purpose from waste water, this method floor space is big, the low temperature aging rate is low, and the treatment time is longer, be suitable for ammonia nitrogen concentration the waste water of＜300mg/L (Li Guofeng. the removal of ammonia nitrogen waste water in the waste water. master thesis. Daqing Petroleum Institute, 2005:7), be not suitable for high-concentration ammonia nitrogenous wastewater.

The chemical precipitation method denitrogenation is a kind of new technology of rising the sixties in 20th century, and this method can be handled the ammonia nitrogen waste water of various concentration, is particularly suitable for the processing of high-concentration ammonia nitrogenous wastewater.Chemical precipitation method is removed ammonia nitrogen and is mainly adopted the MAP precipitator method at present, and its product is MgNH ₄PO ₄Can also be used as fertilizer, but its reagent cost is very high, for the higher concentration ammonia nitrogen waste water adopt this method handle its ammonia nitrogen waste water concentration of back still the higher level of 300～500mg/L (Li Guofeng. the removal of ammonia nitrogen waste water in the waste water. master thesis. Daqing Petroleum Institute, 2005:11), still need to reach wastewater discharge standard with other ammonia nitrogen processing method couplings.

Though more than various treatment technologies all can remove ammonia nitrogen effectively to a certain extent, the defective that himself can't overcome is all arranged, await seeking more simple, economy, effective means.

Summary of the invention

The treatment process that the purpose of this invention is to provide the comprehensive utilization of a kind of waste water, easy to operate, effect stability, adaptability is strong, the processing cycle is short, does not produce the deposition vanadium mother liquid of secondary pollution.

For achieving the above object, the technical solution used in the present invention is: press earlier $m_{{\mathrm{FeSO}}_4}:m_{\mathrm{Cr}}=30:1~40:1$ Mass ratio in deposition vanadium mother liquid, add FeSO ₄7H ₂O, reaction 2～5min; Regulate pH=7～8 with the CaO emulsion again, reaction 20～30min gets filtrate and filter cake through solid-liquid separation; Then filtrate is regulated with NaOH solution and keep pH=8.5～10, under 50～80 ℃ of conditions, adopt air stripping method that the ammonia in the solution is blown out, the ammonia that blows out obtains ammonium salt by acid spray liquid crystallization, and ammonium salt returns ammonium salt precipitation operation; Except that the filtrate behind the ammonia is regulated pH=9.5～10.5 with the CaO emulsion earlier, reaction 10～15min uses the CaO emulsion to regulate pH=10.5～12 again, and reaction 10～15min gets alkaline processing liquid through solid-liquid separation.

Wherein, described acid spray liquid is an alkaline processing liquid spray bone coal baking flue gas gained.

Owing to adopt technique scheme, the present invention at first adopts chemical method to remove heavy metal, air stripping ammonia then, acid spray liquid absorbs ammonia and makes ammonium salt, ammonium salt returns ammonium salt precipitation operation, except that the filtrate behind the ammonia gets alkaline processing liquid after lime method is handled, spray bone coal baking flue gas utilizes again, has realized the comprehensive utilization of waste water.

Therefore, the characteristics that the present invention has the waste water comprehensive utilization, adaptability is strong, technological operation is convenient, the processing cycle short, do not produce secondary pollution, treatment effect is good.

Description of drawings

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

Embodiment

The invention will be further described below in conjunction with the drawings and specific embodiments:

Embodiment 1

A kind of treatment process of deposition vanadium mother liquid, its treatment process be as shown in Figure 1: press earlier $m_{{\mathrm{FeSO}}_4}:m_{\mathrm{Cr}}=30:1~36:1$ Mass ratio in deposition vanadium mother liquid, add FeSO ₄7H ₂O, reaction 2～3min; Regulate pH=7～8 with the CaO emulsion again, reaction 20～25min gets filtrate and filter cake through solid-liquid separation; Then filtrate is regulated with NaOH solution and keep pH=8.5～9.0, under 50～70 ℃ of conditions, adopt air stripping method that the ammonia in the solution is blown out, the ammonia that blows out obtains ammonium salt by acid spray liquid crystallization, and ammonium salt returns ammonium salt precipitation operation; Except that the filtrate behind the ammonia is regulated pH=9.5～10.0 with the CaO emulsion earlier, reaction 10～15min uses the CaO emulsion to regulate pH=10.5～12 again, and reaction 10～15min gets alkaline processing liquid through solid-liquid separation.Acid spray liquid is an alkaline processing liquid spray bone coal baking flue gas gained.

Embodiment 2

A kind of treatment process of deposition vanadium mother liquid, its treatment process be as shown in Figure 1: press earlier $m_{{\mathrm{FeSO}}_4}:m_{\mathrm{Cr}}=36:1~40:1$ Mass ratio in deposition vanadium mother liquid, add FeSO ₄7H ₂O, reaction 3～5min; Regulate pH=7～8 with the CaO emulsion again, reaction 25～30min gets filtrate and filter cake through solid-liquid separation; Then filtrate is regulated with NaOH solution and keep pH=9.0～10.0, under 70～80 ℃ of conditions, adopt air stripping method that the ammonia in the solution is blown out, the ammonia that blows out obtains ammonium salt by acid spray liquid crystallization, and ammonium salt returns ammonium salt precipitation operation; Except that the filtrate behind the ammonia is regulated pH=10.0～10.5 with the CaO emulsion earlier, reaction 10～15min uses the CaO emulsion to regulate pH=10.5～12 again, and reaction 10～15min gets alkaline processing liquid through solid-liquid separation.Acid spray liquid is an alkaline processing liquid spray bone coal baking flue gas gained.

Deposition vanadium mother liquid principal pollutant change in concentration before and after this embodiment is handled is as shown in table 1.

Principal pollutant concentration (mg/L) before and after table 1 deposition vanadium mother liquid is handled

	V	Cr	NH 4 +
				Before deposition vanadium mother liquid is handled	22.8～25.2	17.3～21.3	10638～11029
After deposition vanadium mother liquid is handled	0.67～1.02	0.07～0.11	112～135

As can be seen from Table 1, principal pollutant concentration significantly reduced after employing embodiment 1,2 handled deposition vanadium mother liquids, can realize recycle.This embodiment has realized the waste water comprehensive utilization, has that adaptability is strong, technological operation is convenient, and the processing cycle is short, does not produce secondary pollution, the characteristics that treatment effect is good.

Claims (2)

1, a kind of treatment process of deposition vanadium mother liquid, it is characterized in that earlier by $m_{{\mathrm{FeSO}}_4}:m_{\mathrm{Cr}}=30:1~40:1$ Mass ratio in deposition vanadium mother liquid, add FeSO ₄7H ₂O, reaction 2～5min; Regulate pH=7～8 with the CaO emulsion again, reaction 20～30min gets filtrate and filter cake through solid-liquid separation; Then filtrate is regulated with NaOH solution and keep pH=8.5～10, under 50～80 ℃ of conditions, adopt air stripping method that the ammonia in the solution is blown out, the ammonia that blows out obtains ammonium salt by acid spray liquid crystallization, and ammonium salt returns ammonium salt precipitation operation; Except that the filtrate behind the ammonia is regulated pH=9.5～10.5 with the CaO emulsion earlier, reaction 10～15min uses the CaO emulsion to regulate pH=10.5～12 again, and reaction 10～15min gets alkaline processing liquid through solid-liquid separation.

2, the treatment process of deposition vanadium mother liquid according to claim 1 is characterized in that described acid spray liquid is an alkaline processing liquid spray bone coal baking flue gas gained.

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