CN101985692A

CN101985692A - Method for removing arsenic and recycling tungsten from tungsten smelting wastewater

Info

Publication number: CN101985692A
Application number: CN201010570566XA
Authority: CN
Inventors: 周良益; 王回生; 胡雷岭
Original assignee: JIANGXI XIUSHUI XIANGGAN NONFERROUS METALS CO Ltd
Current assignee: JIANGXI XIUSHUI XIANGGAN NONFERROUS METALS CO Ltd
Priority date: 2010-12-02
Filing date: 2010-12-02
Publication date: 2011-03-16

Abstract

The invention discloses a method for removing arsenic and recycling tungsten from tungsten smelting wastewater, which comprises the following steps of: 1, adding inorganic acid into waste liquor after sodium tungstate solution is subjected to strongly basic anion resin exchange to adjust the waste liquor to be faintly acid, namely pH=3-6, and simultaneously adding a trace amount of flocculating agent; 2, injecting the faintly acid wastewater from which suspended matters are filtered out into an exchange column filled with D313 or D314 type anion resin, and adsorbing all arsenic and phosphorus in the wastewater by using the D type anion resin; and 3, desorbing the resin by using caustic soda solution, making 90 percent of tungsten crystallized and separated out in a form of Na2WO4.2H2O, reacting most harmful elements with an additive, and removing a slag phase. The method has the advantages that: the resin can thoroughly adsorb the tungsten and arsenic, so that the harmful element arsenic in the discharged production wastewater is reduced to less than 0.05mg/L from 1.5mg/L; the metal recovery rate is improved to 96-97 percent from 93-94 percent; and the tungsten detection in the in-process control process is saved, so the operation is simplified, the product quality is ensured, and the consumption of a NH4Cl strippant and water can be reduced.

Description

The recovery method of the removing of arsenic and tungsten in the tungsten smelting wastewater

Technical field

The present invention relates to a kind of method of comprehensive utilization of tungsten smelting wastewater, relate in particular to the removing of arsenic in a kind of tungsten smelting wastewater and the recovery method of tungsten.

Background technology

The production of the ammonium paratungstate (APT) of China is generally adopted the ion exchange process of independent research at present.Its advantage is a constant product quality, and is easy and simple to handle.But it is very big that the significant drawback of this technology is a water consumption, and 1 ton of APT water loss of every production reaches more than 100 tons.Objectionable impurities in the raw material such as arsenic, phosphorus and organic flotation reagent etc. not by resin absorption, enter more than 95% in the factory effluent (exchange back liquid) in ion exchange process; The tungsten resource of China is through the exploitation in century more than one in addition, and the fine tungsten ore is fewer and feweri, especially with the shortage day by day of wolframite resource.The tungsten raw materials for metallurgy of China mostly is various nonstandard concentrate at present, based on white tungsten moderate ore deposit, black (in vain) tungsten slurry.This class raw material also contains a large amount of flotation reagents except that containing the harmful element that exceeds standard, it brings harmful effect to the whole process that APT produces, and particularly ion exchange process is caused disadvantageous effect, has not only reduced the exchange capacity of resin, also influences resin to WO ₄ ^2-" leakage " phenomenon of tungsten takes place in the thoroughness of absorption from start to finish, makes in the factory effluent except that containing above-mentioned harmful element, also contains micro-tungsten, has not only polluted water resources, has also reduced APT and has produced metal recovery rate.Each APT factory of China does not all do to remove and recycling because of the technology that does not have to be suitable for to the above-mentioned element in the factory effluent at present.

Summary of the invention

The purpose of this invention is to provide the removing of arsenic in a kind of tungsten smelting wastewater and the recovery method of tungsten, remove APT and produce organic flotation reagent in the big discharge capacity waste water and harmful element arsenic, phosphorus; When removing harmful element, reclaim " leakage " to the valuable metal tungsten of handing in the liquid of back.Make the harmful element in the efflux wastewater, organic flotation reagent, suspended substance reach discharging standards, avoid their pollutions water resources.

The present invention is achieved like this, it is that to increase by one scale after sodium tungstate solution strongly basic anionic resin exchange less, the very big D type resin anion(R.A) of loading capacity exchange operation, the thoroughly arsenic that do not adsorbed of absorption, phosphorus and disturb " leakage " to the noble metal tungsten of handing in the liquid of back because of flotation reagent by strongly basic anionic resin; Its method steps is: 1. in the waste liquid after the exchange of sodium tungstate solution strongly basic anionic resin, add mineral acid (hydrochloric acid or sulfuric acid) it is transferred to slightly acidic pH=3-6, add micro-flocculation agent (polyacrylamide) simultaneously, make a large amount of flotation reagents in the solution, silicic acid etc. flocculate into fine solid phase particles, by the PE sintering pipe filter of environmental protection special use, thoroughly remove their interference again to D type resin anion(R.A) exchange process; 2. with the slightly acidic waste water behind the filtering suspended substance, inject the exchange column that D type resin anion(R.A) is housed, the arsenic in the waste water, phosphorus are all adsorbed by D type resin anion(R.A):

3RNH ₃Cl+As(p)O ₄ ^3-=[RNH ₃] ₃As(p)O ₄+3Cl ^-

Simultaneously, " leakage " is extremely rare (less than 0.01mol/L WO because of concentration to the tungsten in the liquid of friendship back in the strongly basic anionic resin exchange process ₃), when solution transfers to pH=3-6 with mineral acid, the WO that exists with single combinate form only ₄ ^2-, HWO ₄ ^-Also all by resin absorption:

2RNH ₃Cl+WO ₄ ^2-=[RNH ₃] ₂WO ₄＋2Cl ^-

RNH ₃Cl+HWO ₄ ^-=[RNH ₃]HWO ₄＋Cl ^-

Realized the zero release of tungsten.3. with soda lye to the resin desorb, stripping liquid concentrates, and makes 90% tungsten with Na ₂WO ₄2H ₂The O crystallization is separated out, and the mother liquor that is enriched with As, P returns the leaching concentrate, makes the harmful element major part enter slag with additive reaction and removes mutually.

Description of drawings

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

Embodiment

As shown in Figure 1, the recovery method step of the removing of arsenic and tungsten is in the tungsten smelting wastewater: 1. in the waste liquid after the exchange of sodium tungstate solution strongly basic anionic resin, add hydrochloric acid it is transferred to slightly acidic pH=3-6, add micro-polyacrylamide simultaneously, make a large amount of flotation reagents in the solution, silicic acid etc. flocculate into fine solid phase particles, by the PE sintering pipe filter of environmental protection special use, thoroughly remove their interference again to D type resin anion(R.A) exchange process; 2. with the slightly acidic waste water behind the filtering suspended substance, inject the exchange column that D type resin anion(R.A) is housed, the arsenic in the waste water, phosphorus are all adsorbed by D type resin anion(R.A); 3. with soda lye to the resin desorb, stripping liquid concentrates, and makes 90% tungsten with Na ₂WO ₄2H ₂The O crystallization is separated out, and the mother liquor that is enriched with As, P returns the leaching concentrate, makes the harmful element major part enter slag with additive reaction and removes mutually.

Produce APT with ion exchange method, 1 ton of product of every production just has 60M ³About contain WO ₃0.1-0.5g/L, NaOH:2-7g/L, NaCl:8-9g/L and a large amount of organic flotation reagent and a small amount of harmful element As(1.5mg/L), liquid after the friendship of P, Si, add tap water and deionized water that washing resin is used, the factory effluent total emission volumn of product per ton has 100-120 M ³China APT peak annual output once reached 60,000 tons since entering the new millennium, and the 90%th, to produce with this method, the annual factory effluent total amount of discharging in this field can reach 7,000,000 M ³This is the critical defect of this technology, but its constant product quality is easy and simple to handle, so still be China APT production main method.

Implement the different ion exchange method of twice condition, can obtain following effect:

1. because of the second road ion-exchange is to carry out under solutions of weak acidity, flotation agent can flocculate into fine solid phase particles in the preceding liquid of friendship under micro-flocculation agent effect, after the filtering, has avoided the difficult point of its interfering ion exchange.Can guarantee the thoroughness of resin, make the harmful element arsenic that effluxes in the factory effluent, reduce to below the 0.05mg/L, guarantee to efflux primary standard As≤0.5mg/L that arsenic content in the factory effluent is lower than " integrated wastewater discharge standard " by 1.5mg/L to the absorption of tungsten, arsenic;

2. can realize the zero release of tungsten the first road strongly basic anionic resin exchange operation " leakage " to handing over the valuable metal in the liquid of back thoroughly to be reclaimed, make metal recovery rate bring up to 96-97% by 93-94%;

3. can make the quantitative saturated absorption of the first road strongly basic anionic resin switching implementation, save of the detection of middle control process, both simplify operation, guarantee quality product again tungsten, more can reduce strippant---NH ₄Cl and water consumption.

Claims

1. the removing of arsenic and the recovery method of tungsten in the tungsten smelting wastewater, it is characterized in that method steps is: 1. in the waste liquid after the exchange of sodium tungstate solution strongly basic anionic resin, add mineral acid it is transferred to slightly acidic pH=3-6, add polyacrylamide simultaneously, make a large amount of flotation reagents in the solution, silicic acid etc. flocculate into fine solid phase particles, by the PE sintering pipe filter of environmental protection special use, thoroughly remove their interference again to D type resin anion(R.A) exchange process; 2. with the slightly acidic waste water behind the filtering suspended substance, inject the exchange column that D313 or D314 type resin anion(R.A) are housed, the arsenic in the waste water, phosphorus are all by D313 or the absorption of D314 type resin anion(R.A); 3. with soda lye to the resin desorb, stripping liquid concentrates, and makes 90% tungsten with Na ₂WO ₄2H ₂The O crystallization is separated out, and the mother liquor that is enriched with As, P returns the leaching concentrate, makes the harmful element major part enter slag with additive reaction and removes mutually.