CN108726767A

CN108726767A - A kind of processing method of catalyst production waste water

Info

Publication number: CN108726767A
Application number: CN201710266213.2A
Authority: CN
Inventors: 殷喜平; 李叶; 王涛; 杨凌; 刘夫足; 陈玉华; 伊红亮; 苑志伟
Original assignee: China Petroleum and Chemical Corp; Sinopec Catalyst Co
Current assignee: China Petroleum and Chemical Corp; Sinopec Catalyst Co
Priority date: 2017-04-21
Filing date: 2017-04-21
Publication date: 2018-11-02
Anticipated expiration: 2037-04-21
Also published as: CN108726767B

Abstract

The present invention relates to sewage treatment fields, disclose the processing method of catalyst production waste water, which contains NH₄ ⁺、SO₄ ^2‑、Cl^‑And Na⁺, this method includes 1) and pending waste water is passed through to the first evaporation of progress in each effect evaporator of multi-effect evaporating device successively, the first concentrate of the first steam containing ammonia and sulfur acid sodium crystal is obtained, the pending waste water contains the catalyst production waste water；2) the first concentrate of the sulfur acid sodium crystal is carried out first to be separated by solid-liquid separation, and is separated by solid-liquid separation obtained liquid phase by first and is passed through the second evaporation of MVR vaporising devices progress, obtain the second steam containing ammonia and the second concentrate；3) second concentrate is subjected to low-temperature treatment, so that sodium sulfate crystal is dissolved, obtains the treatment fluid of sodium chloride-containing crystal；4) treatment fluid of the sodium chloride-containing crystal second is carried out to be separated by solid-liquid separation.Ammonium and sodium sulphate, sodium chloride in waste water can be separately recovered in this method, farthest recycle the resource in waste water.

Description

A kind of processing method of catalyst production waste water

Technical field

The present invention relates to sewage treatment fields, and in particular, to a kind of processing method of catalyst production waste water, especially It is related to a kind of containing NH₄ ⁺、SO₄ ^2-、Cl^-And Na⁺Catalyst production waste water processing method.

Background technology

In the production process of oil refining catalyst, a large amount of sodium hydroxide, hydrochloric acid, sulfuric acid, ammonium salt, sulfate, salt are needed The inorganic acids alkali salt such as hydrochlorate generates and largely contains ammonium, sodium sulphate and sodium chloride and alumino-silicate combined sewage.For such Sewage, common practice is first in the range of adjusting pH value to 6~9, after removing most suspended substances, then to adopt in the prior art The removing of ammonium ion is carried out with biochemical process, blow-off method or vaporizing extract process, then, by saline sewage through overregulating pH value, the big portion of removing Divide suspended matter, remove hardness, except silicon and partial organic substances and then by ozone biological activated carbon adsorption and oxidation or other advanced oxygen Change method oxidation removal major part organic matter, then, after further removing hardness into ion interchange unit, into thickening device After (such as reverse osmosis and/or electrodialysis) concentration, then using MVR evaporative crystallizations or multiple-effect evaporation crystallization, obtain the sulphur containing a small amount of ammonium salt Sour sodium and sodium chloride mixing carnallite；Either；First adjust pH value in the range of 6.5~7.5, removing most suspended substances, so Afterwards, it removes hardness, remove silicon and partial organic substances, gone using ozone biological activated carbon adsorption and oxidation or the oxidation of other advanced oxidation processes It is (such as reverse osmosis and/or electric into thickening device after further removing hardness into ion interchange unit after most of organic matter Dialysis) after concentration, then crystallized using MVR evaporative crystallizations or multiple-effect evaporation, sodium sulphate and the sodium chloride mixing for obtaining ammonium salt-containing are miscellaneous Salt.But these carnallites containing ammonium are difficult to handle at present, or the processing cost is high, also, the process of removing early period ammonium ion, Add additional the processing cost of waste water.

In addition, biochemical process deamination can only handle the waste water of low ammonium content, and due to COD contents deficiency in Catalyst sewage Biochemical treatment cannot be directly carried out, machine object, such as glucose or starch are also additionally supplemented with during biochemical treatment, just may be used To handle ammoniacal nitrogen using biochemical process.Sixty-four dollar question is biochemical process deamination treated waste water often total nitrogen (nitre not up to standard Acid ion, nitrite ion content are exceeded), it is also necessary to advanced treating, in addition the content of salt does not reduce (20g/ in waste water L~30g/L), it is unable to direct emission, needs further to carry out desalting processing.

Air- extraction deamination needs to add a large amount of adjusting PH with base value, alkaline consumption is very high, due to de- to deviate from the ammoniacal nitrogen in waste water The alkali in waste water after ammonia cannot recycle, and treated, and pH value of waste water is very high, and the processing cost is high, and air lift rear catalyst is dirty The not big variation of COD contents in water, the salt content in waste water do not reduce (20g/L~30g/L), are unable to direct emission, It needs further to carry out desalting processing, wastewater treatment operating cost is high, remains a large amount of alkali in treated waste water, pH value is very Height, waste is big, and processing cost is up to 50 yuan/ton.

Invention content

The purpose of the present invention is overcome to contain NH in the prior art₄ ⁺、SO₄ ^2-、Cl^-And Na⁺Cost for wastewater treatment it is high, and The problem of can only obtain mixing salt crystal provides and a kind of at low cost and environmentally friendly contains NH₄ ⁺、SO₄ ^2-、Cl^-And Na⁺Waste water at Ammonium and sodium sulphate, sodium chloride in waste water can be separately recovered in reason method, this method, farthest recycle the money in waste water Source.

To achieve the goals above, the present invention provides a kind of processing method of catalyst production waste water, catalyst production Waste water contains NH₄ ⁺、SO₄ ^2-、Cl^-And Na⁺, this approach includes the following steps,

1) pending waste water is passed through successively in each effect evaporator of multi-effect evaporating device and carries out the first evaporation, obtain first First concentrate of steam containing ammonia and sulfur acid sodium crystal, the pending waste water contain the catalyst production waste water；

2) the first concentrate of the sulfur acid sodium crystal is carried out first to be separated by solid-liquid separation, and first is separated by solid-liquid separation and is obtained Liquid phase be passed through MVR vaporising devices carry out second evaporation, obtain the second steam containing ammonia and sulfur acid sodium crystal and sodium chloride crystalline substance Second concentrate of body；

3) the second concentrate of the sulfur acid sodium crystal and sodium chloride crystal is subjected to low-temperature treatment, makes sodium sulfate crystal Dissolving, obtains the treatment fluid of sodium chloride-containing crystal；

4) treatment fluid of the sodium chloride-containing crystal second is carried out to be separated by solid-liquid separation；

Wherein, before the pending waste water is passed through multi-effect evaporating device, the pH value of the pending waste water is adjusted More than 9；The first steam containing ammonia that the rear 1st effective evaporator of the multi-effect evaporating device evaporates is passed through preceding 1st effective evaporator In, the pending waste water and the first steam counter-flow containing ammonia heat exchange；First evaporation makes sodium chloride not crystallize precipitation； Relative to the SO contained in 1 mole of pending waste water₄ ^2-, the Cl that contains in the pending waste water^-It is 14 moles or less.

Through the above technical solutions, for NH is contained₄ ⁺、SO₄ ^2-、Cl^-And Na⁺Waste water, by advance by pending waste water After pH value is adjusted to specific range, recycles the isolated sodium sulfate crystal of the first evaporation and compared with concentrated ammonia liquor, then recycle Second evaporation obtains the concentrate of sulfur acid sodium crystal and sodium chloride crystal and compared with weak aqua ammonia, finally makes concentration using low-temperature treatment Sodium sulphate dissolving in liquid, sodium chloride further crystallize precipitation, obtain sodium chloride crystallization.This method can respectively obtain high-purity Sodium sulphate and sodium chloride, avoid mixed salt processing and recycle during difficulty, be completed at the same time separation of ammonia and the process of salt, And makes waste water heating and steam cooling containing ammonia simultaneously using heat exchange method, be not necessarily to condenser, rationally using in evaporation process Heat, it is energy saving, reduce cost for wastewater treatment, the ammonium in waste water recycle in the form of ammonium hydroxide, and sodium chloride and sodium sulphate divide It is not recycled with crystal form, whole process does not have waste residue and liquid generation, realizes the purpose to turn waste into wealth.

Further, this method is matched by the second evaporation and low-temperature treatment so that the second evaporation can be in higher temperatures Degree is lower to carry out, and improves the solid content and evaporation efficiency in the second evaporation concentrated solution, can be simultaneously reached energy-saving effect.

Further, this method carries out the first evaporation by multi-effect evaporating device, and the first effect and/or the can be collected separately The condensate liquid of the first steam containing ammonia evaporated in 2nd effect evaporator, consequently facilitating obtaining higher first ammonium hydroxide of concentration.

Other features and advantages of the present invention will be described in detail in subsequent specific embodiment part.

Description of the drawings

Attached drawing is to be used to provide further understanding of the present invention, an and part for constitution instruction, with following tool Body embodiment is used to explain the present invention together, but is not construed as limiting the invention.In the accompanying drawings：

Fig. 1 is a kind of flow diagram of the catalyst production waste water processing method of embodiment provided by the invention.

Reference sign

1, MVR vaporising devices 73, third circulating pump

2, multi-effect evaporating device 74, the 4th circulating pump

31, the first heat-exchanger rig 76, the 6th circulating pump

32, the second heat-exchanger rig 77, the 7th circulating pump

33, third heat-exchanger rig 78, the 8th circulating pump

34, the 4th heat-exchanger rig 79, the 9th circulating pump

35, the 5th heat-exchanger rig 80, the tenth circulating pump

51, the first tank used for storing ammonia 81, vacuum pump

52, the second tank used for storing ammonia 82, circulating water pool

53, the first mother liquor tank 83, tail gas absorber

54, the second mother liquor tank 85, the 15th circulating pump

55, low-temperature treatment tank 86, the 16th circulating pump

56, brilliant liquid collecting tank 87, the 17th circulating pump

61, the first pH value measuring device 91, the first equipment for separating liquid from solid

62, the second pH value measuring device 92, the second equipment for separating liquid from solid

71, first circulation pump 102, compressor

Specific implementation mode

The specific implementation mode of the present invention is described in detail below.It should be understood that described herein specific Embodiment is merely to illustrate and explain the present invention, and is not intended to restrict the invention.

The endpoint of disclosed range and any value are not limited to the accurate range or value herein, these ranges or Value should be understood as comprising the value close to these ranges or value.For numberical range, between the endpoint value of each range, respectively It can be combined with each other between the endpoint value of a range and individual point value, and individually between point value and obtain one or more New numberical range, these numberical ranges should be considered as specific open herein.

Below in conjunction with Fig. 1, the present invention will be described, and the present invention is not limited by Fig. 1.

The processing method of catalyst production waste water provided by the invention, the catalyst production waste water contain NH₄ ⁺、SO₄ ^2-、Cl^- And Na⁺, this approach includes the following steps,

1) pending waste water is passed through successively in each effect evaporator of multi-effect evaporating device 2 and carries out the first evaporation, obtain the First concentrate of one steam containing ammonia and sulfur acid sodium crystal, the pending waste water contain the catalyst production waste water；

2) the first concentrate of the sulfur acid sodium crystal is carried out first to be separated by solid-liquid separation, and first is separated by solid-liquid separation and is obtained Liquid phase be passed through MVR vaporising devices 1 carry out second evaporation, obtain the second steam containing ammonia and sulfur acid sodium crystal and sodium chloride crystalline substance Second concentrate of body；

Wherein, before the pending waste water is passed through multi-effect evaporating device 2, the pH value of the pending waste water is adjusted More than 9；The first steam containing ammonia that the rear 1st effective evaporator of the multi-effect evaporating device 2 evaporates is passed through preceding 1st effective evaporator In, the pending waste water and the first steam counter-flow containing ammonia heat exchange；First evaporation makes sodium chloride not crystallize precipitation； Relative to the SO contained in 1 mole of pending waste water₄ ^2-, the Cl that contains in the pending waste water^-It is 14 moles or less.

Preferably, the pending waste water is the catalyst production waste water；Alternatively, the pending waste water contain it is described Catalyst production waste water and described second is separated by solid-liquid separation obtained liquid phase.

It is highly preferred that the pending waste water is the catalyst production waste water is separated by solid-liquid separation obtained liquid with described second At least part of mixed liquor of phase.

It is obtained with second separation of solid and liquid it is further preferred that the pending waste water is the catalyst production waste water Liquid phase mixed liquor.

Preferably, before the pending waste water is passed through multi-effect evaporating device 2, the pH of the pending waste water is adjusted Value is more than 10.8.In addition, for the pending waste water pH value the upper limit there is no limit, such as can be 14 hereinafter, it is preferred that For 13.5 hereinafter, more preferably 13 or less.

Method provided by the invention, which can be directed to, contains NH₄ ⁺、SO₄ ^2-、Cl^-And Na⁺Waste water handled, in addition to containing NH₄ ⁺、SO₄ ^2-、Cl^-And Na⁺Outside, to the catalyst production waste water, there is no particular limitation.From the treatment effeciency for improving waste water Angle considers, relative to the SO contained in 1 mole of pending waste water₄ ^2-, the Cl that contains in the pending waste water^-For 13.8 moles hereinafter, preferably 13.75 moles hereinafter, more preferably 13.5 moles hereinafter, further preferably 13 moles hereinafter, Still more preferably be 12 moles hereinafter, be still more preferably 11 moles hereinafter, be still more preferably 10.5 moles hereinafter, Preferably 2 moles or more, more preferably 2.5 moles or more, further preferably 3 moles or more, such as can be 1-10 moles, Preferably 5-8 moles.By by SO₄ ^2-And Cl^-Molar ratio control in above range, sodium sulphate can be made to analyse in the first evaporation Go out and sodium chloride is not precipitated, to achieve the purpose that efficiently separate sodium sulphate.In addition, it is as above described below, in the present invention also Can be by the second Recycling Mother Solution obtained in the second evaporation process to the first evaporation, and thus come in pending waste water SO₄ ^2-And Cl^-Molar ratio be adjusted, and the balance of sodium hydroxide can be maintained.

In the present invention, the first heat exchange, adjust the pH value of the pending waste water and the tune of the pending waste water With process, (the pending waste water contains the case where catalyst production waste water is separated by solid-liquid separation obtained liquid phase with described second Under, need the allocation process for carrying out the pending waste water) carry out priority there is no particular limitation, can be fitted as needed When selection, before the pending waste water is passed through multi-effect evaporating device 2 complete.

In the present invention, first evaporation makes sodium chloride not crystallize precipitation, refers to that the sodium chloride of control mixed system is dense Degree is no more than the solubility under the first evaporation conditions (including but not limited to temperature, pH value etc.), it is not excluded that sulfate crystal presss from both sides The sodium chloride of band or adsorption.Since the water content of crystal after separation of solid and liquid is different, chlorine in the sodium sulfate crystal generally yielded Change the content of sodium below 8 mass % (preferably 4 mass %), in the present invention, sodium chloride in obtained sodium sulfate crystal It can think that sodium chloride does not crystallize precipitation when content is below 8 mass %.

In the present invention, second evaporation needs that sodium sulfate crystal is made to dissolve in low-temperature treatment, specifically, the The second concentrate of sulfur acid sodium crystal and sodium chloride crystal is obtained in two evaporations, need to ensure that sodium sulfate crystal therein can be It is completely dissolved in low-temperature treatment.By controlling the evaporation capacity of second evaporation, makes sodium sulphate, sodium chloride while crystallizing precipitation (the i.e. second evaporation obtains the second concentrate of sulfur acid sodium crystal and sodium chloride crystal), then sulfur-bearing is made by the low-temperature treatment Sodium sulfate crystal dissolving in second concentrate of sour sodium crystal and sodium chloride crystal, sodium chloride further crystallize precipitation, obtain Contain only the treatment fluid of sodium chloride crystal.Treatment fluid about the sodium chloride-containing crystal, it is not excluded that sodium chloride crystallization entrainment or The sodium sulphate of adsorption.Since the water content of crystal after separation of solid and liquid is different, sodium sulphate in the sodium chloride crystal generally yielded Content below 8 mass % (preferably 4 mass %), in the present invention, the content of sodium sulphate in obtained sodium chloride crystal It can think that sodium sulphate has dissolved when below 8 mass %.

In the present invention, it is to be understood that first steam containing ammonia and second steam containing ammonia are this field So-called indirect steam.The pending waste water and the first steam counter-flow containing ammonia heat exchange are referred to using in multiple-effect evaporation Countercurrent flow.The pressure is the pressure in terms of gauge pressure.

In the present invention, there is no particular limitation for each effect evaporator of the multi-effect evaporating device 2, can be normal by this field Advise the various evaporators composition used.Such as can selected from downward film evaporator, film-rising evaporator, scraper-type evaporator, in It entreats in circulating tube type multi-effect evaporator, basket evaporator, external heating type evaporator, forced-circulation evaporator and Liewen evaporator It is one or more.Wherein, preferably forced-circulation evaporator, external heating type evaporator.Each effect of the multi-effect evaporating device 2 is steamed Hair device is formed by heating room and vaporization chamber respectively, can also include other evaporation accessories as needed, for example, make liquid foam into The demister of one step separation, the vacuum plant the etc. when condenser and decompression operation that make indirect steam all condense.It is described more There is no particular limitation for the evaporator quantity that effect vaporising device 2 contains, and can be 2 effects or more, preferably 2-5 is imitated, more preferably 3-4 is imitated.

It in the present invention, can be in order to which the pending waste water to be passed through to each effect evaporator of multi-effect evaporating device 2 successively Circulating pump is set between each effect evaporator, the waste water after the evaporation of preceding 1st effective evaporator is passed through latter effect by the circulating pump Evaporator.

In the present invention, the circulating pump between selected each effect evaporator can be various forms commonly used in the art Pump, generate a large amount of fine grain cores to make material be uniformly evaporated, avoid, prevent crystal grain and impeller high velocity impact in cycle magma Generate a large amount of secondary nucleus, the circulating pump is preferably the centrifugal pump of the slow-speed of revolution, more preferably big flow, the slow-speed of revolution guide pump Wheel or big flow, low lift, the slow-speed of revolution axial-flow pump.

A preferred embodiment according to the present invention, first evaporation carries out in multi-effect evaporating device 2, described Multi-effect evaporating device 2 is by 1st effective evaporator 2a, 2nd effect evaporator 2b, third effect evaporator 2c and fourth evaporator 2d groups At.By the pending waste water be passed through successively the 1st effective evaporator 2a of the multi-effect evaporating device 2,2nd effect evaporator 2b, It is evaporated in third effect evaporator 2c and fourth evaporator 2d, obtains the first concentrate of sulfur acid sodium crystal.It will be described Before the first steam containing ammonia evaporated in the rear 1st effective evaporator of multi-effect evaporating device 2 is passed through hot friendship is carried out in 1st effective evaporator It changes and obtains the first ammonium hydroxide.It is highly preferred that first ammonium hydroxide carries out first in the first heat-exchanger rig 31 with pending waste water Heat exchange makes full use of energy.Heating steam (life steam i.e. commonly used in the art) is passed through in fourth evaporator 2d, The condensation water that heating steam obtains after being condensed in fourth evaporator 2d, condensation water enter multi-effect evaporating device 2 for preheating The pending waste water after, be used further to prepare sodium sulphate washing solution.

In the present invention, the condition of first evaporation can be selected suitably as needed, reach make sulfate crystal and Make the purpose that sodium chloride is not precipitated.It is described first evaporation condition may include：Temperature be 35 DEG C or more, pressure be- 95kPa or more；In order to improve the efficiency of evaporation, and from the point of view of reducing equipment cost and energy consumption, it is preferable that described first The condition of evaporation includes：Temperature is 45 DEG C~365 DEG C, and pressure is -95kPa~18110kPa；Preferably, it is described first evaporation Condition includes：Temperature is 60 DEG C~365 DEG C, and pressure is -87kPa~18110kPa；Preferably, the condition packet of first evaporation It includes：Temperature is 75 DEG C~175 DEG C, and pressure is -73kPa~653kPa；Preferably, the condition of first evaporation includes：Temperature It it is 80 DEG C~130 DEG C, pressure is -66kPa~117kPa；Preferably, the condition of first evaporation includes：Temperature be 95 DEG C~ 115 DEG C, pressure is -37kPa~33kPa；It is particularly preferred that the condition of first evaporation includes：Temperature is 100 DEG C~115 DEG C, pressure is -23kPa~33kPa.In the present invention, it is described first evaporation condition refer to multi-effect evaporating device last Imitate the evaporation conditions of evaporator.

In order to make full use of the heat in evaporation process, in the first evaporation, the evaporating temperature of preceding 1st effective evaporator is than latter Imitate low 5 DEG C of evaporator or more, preferably low 5 DEG C~30 DEG C, more preferably low 10 DEG C~20 DEG C.

In the present invention, the operating pressure of the first evaporation is preferably the saturated vapor pressure of evaporated feed liquid.

In the present invention, the flow of the first evaporation can suitably be selected according to the ability that equipment is handled, such as can be 0.1m³/ h or more (such as 0.1m³/ h~500m³/h)。

, can be while ensureing sulfate crystal by making the first evaporation carry out under these conditions, sodium chloride is not tied Crystalline substance, the purity for the sodium sulfate crystal that thereby may be ensured that.

Contained ammonia in the pending waste water can be evaporated by the condition of the first evaporation of control according to the present invention 90 mass % or more (preferably 95 mass % or more), to obtain higher first ammonium hydroxide of concentration, the first ammonium hydroxide can be direct Be back to the production process of catalyst, either with acid neutralization obtain carrying out after ammonium salt reuse or with water and corresponding ammonium salt or Ammonium hydroxide allotment uses.In the first evaporation, 1st effective evaporator and/or the can be collected separately in denseer ammonium hydroxide in order to obtain The condensation water of the first steam containing ammonia obtained in 2nd effect evaporator, that is, collect 2nd effect evaporator and/or triple effect evaporation The liquid of steam condensation containing ammonia obtained in device.Above-mentioned first ammonium hydroxide as needed can be independent or converges collection.In order to control ammonium hydroxide Concentration can suitably adjust the evaporation conditions of each effect evaporator.

According to the present invention, first evaporation is not so that (i.e. chlorination is precipitated in the sodium chloride crystallization in the pending waste water Sodium is not up to supersaturation), it is preferable that first evaporation makes a concentration of X or less of sodium chloride in the first concentrate (preferably 0.999X is hereinafter, more preferably 0.95X-0.999X, further preferred 0.99X-0.9967X), wherein X is in the first evaporation Under the conditions of, the concentration of sodium chloride when sodium sulphate and sodium chloride reach saturation in the first concentrate.Pass through the journey evaporated first Degree control within the above range, can be such that sulfate crystal as much as possible is precipitated under conditions of ensureing that sodium chloride is not precipitated. By making sulfate crystal in the first evaporation as possible, waste water treatment efficiency can be improved, energy waste is reduced.

In the present invention, the carry out degree of first evaporation is in such a way that the first evaporation of monitoring obtains the concentration of liquid It carries out, specifically, the concentration for obtaining liquid by the first evaporation of control makes the first evaporation not make described in above-mentioned range Sodium chloride crystallization in pending waste water is precipitated.Here first evaporation obtain the concentration of liquid, by way of measuring density into Row monitoring can specifically use densitometer to carry out density measure.

A preferred embodiment according to the present invention, before the pending waste water is passed through multi-effect evaporating device, The pending waste water is subjected to the first heat with the first ammonium hydroxide (the first liquid of steam condensation containing ammonia) obtained from multi-effect evaporating device It exchanges.Preferably, the first steam containing ammonia for the 1st effective evaporator of the multi-effect evaporating device being obtained with it is described pending useless Water carries out the first heat exchange and obtains the first ammonium hydroxide.There is no particular limitation for the mode of first heat exchange, this may be used The heat exchange mode of field routine carries out.The number of the heat exchange can be preferably 2-4 times, more preferably 2-3 more than primary It is secondary.By the heat exchange, the ammonium hydroxide of output is further cooled, and heat utmostly recycles inside processing unit, rationally The energy is utilized, reduces waste.

A preferred embodiment according to the present invention, first heat exchange pass through the first heat-exchanger rig 31, third Heat-exchanger rig 33 and the 5th heat-exchanger rig 35 carry out, specifically, by the first liquid of steam condensation containing ammonia by the first heat-exchanger rig 31, The second liquid of steam condensation containing ammonia (higher second ammonium hydroxide of temperature) that MVR vaporising devices 1 are obtained by third heat-exchanger rig 33, At least partly concentrate that MVR vaporising devices 1 obtain is passed through into the 5th heat-exchanger rig 35；And by one of the pending waste water Divide through the first heat-exchanger rig 31, another part passes through the 5th heat-exchanger rig 35 by third heat-exchanger rig 33, rest part；So The pending waste water of above-mentioned three parts is merged afterwards.By the first heat exchange, the pending waste water heating is made to be convenient for evaporating, Make the first steam condensation containing ammonia liquid cool down to obtain the first ammonium hydroxide simultaneously, while the second steam condensation containing ammonia liquid being made to cool down The second ammonium hydroxide is obtained, while the second concentrate cooling being made to be convenient for low-temperature treatment.

A preferred embodiment according to the present invention, 1st effective evaporator (the first effect evaporation of multi-effect evaporating device 2 Device 2a) obtained the first steam containing ammonia of evaporation in the second heat-exchanger rig 32 with cold medium progress heat exchange and obtain ammonium hydroxide, and It is stored in the first tank used for storing ammonia 51.Cold medium therein can be cooling water, glycol water etc..Use conventional cooling When water, the cooling water circulation uses, when using the catalyst production waste water as cooling water, the catalyst production after heat exchange Waste water preferably directly returns to processing procedure (being such as back to first time pH value adjustment process).

In the present invention, for first heat-exchanger rig 31, the second heat-exchanger rig 32, third heat-exchanger rig 33 and the 5th There is no particular limitation for heat-exchanger rig 35, can use various heat exchangers commonly used in the art, reach with it is described pending Waste water carries out the purpose of first heat exchange.Specifically, it can be jacketed type exchanger, plate heat exchanger, shell-and-tube Heat exchanger etc., wherein preferably plate heat exchanger.The material of the heat exchanger can be specifically chosen as needed, such as in order to support Resisting corrosion of chlorine ion can select material for two phase stainless steel, the heat exchanger of titanium or titanium alloy, Hastelloy, relatively low in temperature When can select the heat exchanger containing plastic material.

It is preferably exchanged heat by described first according to the present invention in order to make full use of the thermal energy of the first liquid of steam condensation containing ammonia After device 31 carries out the first heat exchange, the temperature of the pending waste water is 40 DEG C~364 DEG C, more preferably 55 DEG C~364 DEG C, Further preferably 65 DEG C~174 DEG C, be still more preferably 79 DEG C~129 DEG C.

It is preferably exchanged heat by the third according to the present invention in order to make full use of the thermal energy of the second liquid of steam condensation containing ammonia After device 33 carries out the first heat exchange, the temperature of the pending waste water is 44 DEG C~174 DEG C, more preferably 79 DEG C~99 DEG C.

According to the present invention, in order to make full use of the thermal energy of the second concentrate, preferably by the 5th heat-exchanger rig 35 into After the first heat exchange of row, the temperature of the pending waste water is 44 DEG C~174 DEG C, more preferably 79 DEG C~129 DEG C.

In the present invention, it is to be understood that first ammonium hydroxide had both included steaming the rear 1st effective evaporator of multiple-effect evaporation It sends out and carries out the first ammonium hydroxide that heat exchange obtains in 1st effective evaporator before the first obtained steam containing ammonia is sent into, also include multiple-effect evaporation The first steam containing ammonia that the 1st effective evaporator of device generates carries out the first ammonia that heat exchange obtains in the second heat-exchanger rig 32 Water.The first ammonium hydroxide of above two parts is come together in jointly in the first tank used for storing ammonia 51.

In the present invention, for the method for pH value adjusting, there is no particular limitation, such as can use additional basic species The mode of matter adjusts the pH value of the pending waste water.There is no particular limitation for the alkaline matter, reaches above-mentioned adjusting pH value Purpose.In order not to introduce new impurity in pending waste water, the purity of gained crystal is improved, the basic species are of fine quality It is selected as NaOH.

Feed postition as the alkaline matter is the feed postition of this field routine, but preferably makes alkaline matter It is mixed in form of an aqueous solutions with the pending waste water, such as the aqueous solution containing alkaline matter can be passed into and import institute It states and is mixed in the pipeline of pending waste water.For the content of alkaline matter in aqueous solution, there is no particular limitation, as long as It can achieve the purpose that above-mentioned adjusting pH value.But it in order to reduce the dosage of water, further reduces the cost, it is preferable to use alkalinity The saturated aqueous solution of substance.In order to monitor the pH value of the pending waste water, can be waited for described in measurement after above-mentioned adjusting pH value Handle the pH value of waste water.

A preferred embodiment according to the present invention, first evaporation process carry out in multi-effect evaporating device 2, The first heat is carried out the pending waste water is sent into the first heat-exchanger rig 31, third heat-exchanger rig 33 or the 5th heat-exchanger rig 35 Before exchange, by the way that the pending waste water is being sent into the first heat-exchanger rig 31, the heat exchange dress of third heat-exchanger rig 33 and the 5th It sets and imports the aqueous solution containing alkaline matter and mixing in 35 main pipeline, to carry out first time pH value adjusting；It then will be described Pending waste water is sent into the second heat-exchanger rig 32 and carries out the first heat exchange, then by the way that the pending waste water is being sent into multiple-effect The aqueous solution containing alkaline matter and mixing are imported in the pipeline of vaporising device 2, to carry out second of pH value adjusting.By twice PH value is adjusted, and pH value of the pending waste water before being passed through multi-effect evaporating device 2 is made to be more than 9, preferably greater than 10.8.It is excellent Selection of land, first time pH value is adjusted so that the pH value of pending waste water is more than 7 (preferably 7-9), and second of pH value is adjusted so that waiting for The pH value for handling waste water is more than 9 (being preferably greater than 10.8).In accordance with the present invention it is preferred that carry out first heat exchange it Before, the pH value for adjusting the pending waste water is more than 7.

In order to detect above-mentioned first time pH value adjust and second of pH value adjust after pH value, preferably will be described pending Waste water, which is sent on the main pipeline of the first heat-exchanger rig 31, third heat-exchanger rig 33 and the 5th heat-exchanger rig 35, is arranged the survey of the first pH value Device 61 is measured to measure the pH value after first time pH value is adjusted, in the pipe that the pending waste water is sent into multi-effect evaporating device 2 Second pH value measuring device 62 is set on road to measure the pH value after second of pH value is adjusted.

According to the present invention, this method can also include the first concentrate by the sulfur acid sodium crystal in crystallization apparatus Crystallization obtains the magma of sulfur acid sodium crystal.Make in crystallization apparatus at this point, the evaporation conditions of first evaporation need to meet Sulfate crystal is precipitated and purpose that sodium chloride is not precipitated.There is no particular limitation for the crystallization apparatus, such as can be Brilliant flow container, brilliant liquid collecting tank, band stir thickener or without stirring thickener etc..A preferred embodiment party according to the present invention Formula, the crystallization carry out in brilliant liquid collecting tank 56.There is no particular limitation for the condition of the crystallization, such as may include：Temperature Degree is 45 DEG C or more, preferably 95 DEG C~107 DEG C, more preferably 85 DEG C~105 DEG C.Crystallization time can be 5min~for 24 hours, excellent It is selected as 5min~30min.According to the present invention, the crystallization process of the first concentrate of the sulfur acid sodium crystal can also with It is carried out in the multi-effect evaporating device (such as forced-circulation evaporation crystallizer) of crystallizer, the temperature crystallized at this time is corresponding first The temperature of evaporation.In the present invention, the temperature of crystallization is preferably identical as the temperature of the first evaporation.

According to the present invention, when being crystallized using individual crystallization apparatus, need to be further ensured that first evaporation not So that (i.e. sodium chloride is not up to supersaturation) is precipitated in sodium chloride crystallization, it is preferable that first evaporation makes first concentrate (preferably 0.999X is hereinafter, more preferably 0.95X-0.999X, further preferred 0.99X- by a concentration of X or less of middle sodium chloride 0.9967X), wherein X is chlorine when sodium chloride and sodium sulphate reach saturation in the first concentrate under conditions of the crystallization Change the concentration of sodium.

In the present invention, the first concentrate of the sulfur acid sodium crystal obtains sodium sulphate crystalline substance after first is separated by solid-liquid separation Body and the first mother liquor (i.e. first is separated by solid-liquid separation obtained liquid phase).There is no particular limitation for described first method being separated by solid-liquid separation, Such as it can be selected from one or more in centrifugation, filtering, sedimentation.

According to the present invention, it (is, for example, centrifuge, belt that the first equipment for separating liquid from solid, which may be used, in first separation of solid and liquid Filter, flame filter press etc.) it carries out.After described first is separated by solid-liquid separation, the first mother liquor that the first equipment for separating liquid from solid 91 obtains It is temporarily stored into the first mother liquor tank 53, and MVR vaporising devices 1 can be sent by the 6th circulating pump 76 and carry out the second evaporation.In addition, The impurity such as certain chlorion, free ammonia, hydroxide ion can be adsorbed by being difficult to avoid that on obtained sodium sulfate crystal, in order to remove The impurity of absorption reduces the peculiar smell of solid salt, reduces corrosivity, improves the purity of the crystal, it is preferable that the sodium sulphate is brilliant Body water, the catalyst production waste water or metabisulfite solution carry out the first washing and drying.In order to avoid sulphur in washing process The dissolving of sour sodium crystal, it is preferable that the sodium sulfate crystal is washed with aqueous sodium persulfate solution.It is highly preferred that the sulfuric acid Sodium chloride and sodium sulphate reach saturation simultaneously at the concentration of the sodium water solution preferably temperature corresponding to sodium sulfate crystal to be washed The concentration of sodium sulphate in aqueous solution.

It is separated by solid-liquid separation the mode washed with first as above-mentioned first, there is no particular limitation, and ability can be used for example The elutriation apparatus and solid-liquid separating equipment of domain routine, which combine, to carry out, can also be in the equipment for separating liquid from solid such as band filter of segmentation Upper progress.Preferably, first washing includes eluriating and/or eluting.For above-mentioned elutriation and elution, there is no particular limitation, It can be carried out by the method for this field routine.It is described elutriation and elution number there is no particular limitation, can be 1 time with On, the sodium sulfate crystal of higher purity, preferably 2-4 times in order to obtain.During elutriation, made with the catalyst production waste water It does not recycle generally when liquid to eluriate, can be used with circulated in countercurrent when doing elutriation liquid using the cleaning solution of the first washing recycling. Before carrying out the elutriation, tentatively separation of solid and liquid is carried out preferably by way of sedimentation and obtains the slurries (liquid of sulfur acid sodium crystal Content is 35 mass % or less, which preferably carries out in the device well known in the art such as settling tank, settling tank).It washes in a pan During washing, relative to the slurries of 1 parts by weight sulfur acid sodium crystal, it is 1~20 parts by weight to eluriate the liquid used.Elution is preferred It is carried out using aqueous sodium persulfate solution.In order to further increase the effect of elutriation, the higher sodium sulfate crystal of purity is obtained, preferably In the case of, the liquid that elution can be used to obtain is washed, it is preferable to use water or metabisulfite solution.The liquid generated for washing Body preferably returns it to before the adjusting completion of the pH value before the first evaporation, such as passes through the 8th circulating pump 78 and return second PH value adjustment process is re-fed into the first MVR vaporising devices 2.

A preferred embodiment according to the present invention contains sodium sulphate by what the evaporation of multi-effect evaporating device 2 obtained The first concentrate, by after settling and be tentatively separated by solid-liquid separation, carrying out in eluriating tank the with the catalyst production waste water It is primary to eluriate, it then reuses the liquid obtained when subsequent wash sodium sulfate crystal and in another elutriation tank wash in a pan for the second time It washes, finally will be sent into equipment for separating liquid from solid by the slurries eluriated twice is separated by solid-liquid separation, and the crystal being separated by solid-liquid separation is again During the liquid for being eluted with aqueous sodium persulfate solution, and elution being obtained is eluriated back to second.By above-mentioned washing process, The purity of the sodium sulfate crystal not only made improves, and will not be excessive introducing cleaning solution, improve the efficiency of wastewater treatment.

In the present invention, there is no particular limitation for the MVR vaporising devices 1, can be commonly used in the art various MVR vaporising devices.Such as can be selected from MVR falling film evaporators, MVR forced-circulation evaporators, the evaporation of MVR-FC continuous crystallisations It is one or more in device, MVR-OSLO continuous crystallisation evaporators.Wherein, preferably MVR forced-circulation evaporators, MVR-FC connect Continuous crystallizing evaporator, more preferably falling liquid film+forced circulation two-stage MVR crystallizing evaporators.

In the present invention, the condition of second evaporation can be selected suitably as needed, and described the can be controlled by reaching Two evaporation evaporation capacity, make sodium sulphate, sodium chloride simultaneously crystallize precipitation (i.e. second evaporate obtain sulfur acid sodium crystal and sodium chloride Second concentrate of crystal), then made in the second concentrate of sulfur acid sodium crystal and sodium chloride crystal by the low-temperature treatment Sodium sulfate crystal dissolving, sodium chloride further crystallizes precipitation, obtains the purpose for the treatment fluid for containing only sodium chloride crystal.Institute The condition for stating the second evaporation may include：Temperature is 35 DEG C or more, and pressure is -95kPa or more；In order to improve evaporation efficiency, and From the point of view of reducing equipment cost and energy consumption, it is preferable that the condition of second evaporation includes：Temperature is 45 DEG C~175 DEG C, pressure is -95kPa~18110kPa；Preferably, the condition of second evaporation includes：Temperature is 60 DEG C~175 DEG C, pressure Power is -87kPa~18110kPa；Preferably, the condition of second evaporation includes：Temperature be 75 DEG C~175 DEG C, pressure be- 73kPa~653kPa；Preferably, the condition of second evaporation includes：Temperature be 80 DEG C~130 DEG C, pressure be -66kPa~ 117kPa；Preferably, the condition of second evaporation includes：Temperature is 95 DEG C~110 DEG C, and pressure is -37kPa~12kPa.It is special Not preferably, the condition of second evaporation includes：Temperature is 107 DEG C~110 DEG C, and pressure is 0kPa~12kPa.

In the present invention, the operating pressure of the second evaporation is preferably the saturated vapor pressure of evaporated feed liquid.

In addition, ability and pending wastewater flow rate that the evaporation capacity of the second evaporation can be handled according to equipment suitably select, Such as can be 0.1m³/ h or more (such as 0.1m³/ h~500m³/h)。

According to the present invention, described second evaporates so that sodium chloride and sodium sulphate in the pending waste water crystallize analysis simultaneously Go out, it is preferable that it is described second evaporation make sodium sulphate in the treatment fluid a concentration of Y or less (preferably 0.9Y-0.99Y, it is more excellent It is selected as 0.95Y-0.98Y), wherein Y is under conditions of low-temperature treatment, and sodium sulphate and sodium chloride reach in pending waste water The concentration of sodium sulphate when saturation.By by second evaporation extent control within the above range, can ensure be precipitated sulfuric acid Sodium can all dissolve under the conditions of low-temperature treatment, while sodium chloride crystallization as much as possible being made to be precipitated.By as possible second So that sodium chloride is crystallized in evaporation, waste water treatment efficiency can be improved, reduces energy waste.

In the present invention, the carry out degree of second evaporation obtains liquid by the evaporation capacity of the second evaporation of monitoring The mode of amount carries out, and specifically, cycles of concentration is controlled by the evaporation capacity i.e. amount of the second ammonium hydroxide of the second evaporation of control, makes the The sulfate crystal being precipitated in two evaporation concentrated solutions can be dissolved in low-temperature treatment.Here the second degree being concentrated by evaporation is led to The mode for crossing measurement evaporation capacity is monitored, and specifically can carry out flow measurement with use quality flowmeter.

By making the second evaporation carry out under these conditions, the efficiency of evaporation can be improved, energy consumption is reduced.Ensureing maximum While evaporation capacity (cycles of concentration), ensure concentrate sulfate crystal fully dissolved after low-temperature treatment, so as to Ensure the purity of obtained sodium chloride crystal.

A preferred embodiment according to the present invention, second evaporation process carry out in MVR vaporising devices 1, First mother liquor is passed through the second evaporation of progress in the MVR vaporising devices 1 by the 6th circulating pump 76 and obtains second containing ammonia Second concentrate of steam and sulfur acid sodium crystal and sodium chloride crystal.

In the present invention, in order to improve the solid content in the MVR vaporising devices 1, the ammonia content in reduction liquid is excellent Choosing will (namely the liquid inside MVR vaporising devices also referred to as follows by partially liq that the MVR vaporising devices 1 evaporate Ring liquid) it flows back into the MVR vaporising devices 1.The above-mentioned process that the circulation fluid is flowed back into the MVR vaporising devices 1 is excellent It is selected as, the circulation fluid is mixed with the first mother liquor, the second optional cleaning solution, again returns to the MVR vaporising devices 1.Example Such as, it is passed through again after being mixed the circulation fluid and the second cleaning solution with the first mother liquor in the duct by the 7th circulating pump 77 After 4th heat-exchanger rig 34 carries out the second heat exchange, MVR vaporising devices 1 are returned.As will by MVR vaporising devices 1 evaporation after Partially liq flow back into the ratios of MVR vaporising devices 1 and be not particularly limited, ensure MVR vaporising devices 1 in given steaming The water and ammonia of requirement can be evaporated at a temperature of hair, such as can be 0.1-100, preferably 5-50.Here, reflux Than referring to：Regurgitant volume subtracts the ratio of regurgitant volume with the total amount of liquid being sent into MVR vaporising devices 1.

In the case of, according to the invention it is preferred to, the method further include after second steam containing ammonia is compressed again Carry out second heat exchange.The compression of second steam containing ammonia can be carried out by compressor 102.By to described second Steam containing ammonia is compressed, to input energy in MVR vapo(u)rization systems, ensure the process of waste water heating-evaporation-cooling continuously into Row is needed to input to start steam when MVR evaporation processes start, only be energized by compressor 102 after reaching continuously running state, no It needs to input other energy again.Various compressors commonly used in the art may be used in the compressor 102, such as centrifuge wind Machine, turbocompressor or lobed rotor compressor etc..After the compression of the compressor 102, the temperature liter of second steam containing ammonia It is 5 DEG C high~20 DEG C.

According to the present invention, there is no particular limitation for the mode that the low-temperature treatment carries out, as long as reaching control temperature appropriate Spend the sodium sulfate crystal dissolving in the second concentrate of the sulfur acid sodium crystal and sodium chloride crystal that make the second evaporation obtain. Preferably, the temperature of the low-temperature treatment is less than the temperature of the second evaporation, and specifically, the condition of the low-temperature treatment can wrap It includes：Temperature be 13 DEG C~100 DEG C, preferably 15 DEG C~45 DEG C, more preferably 15 DEG C~35 DEG C, further preferably 17.9 DEG C~ 35 DEG C, be still more preferably 25 DEG C~35 DEG C；Such as can be 18 DEG C, 19 DEG C, 20 DEG C, 21 DEG C, 22 DEG C, 23 DEG C, 24 DEG C, 25 ℃、26℃、27℃、28℃、29℃、30℃、31℃、32℃、33℃、34℃、35℃、36℃、37℃、38℃、39℃、40 DEG C, 41 DEG C, 42 DEG C, 43 DEG C, 44 DEG C, 45 DEG C, 46 DEG C, 47 DEG C, 48 DEG C, 49 DEG C, 50 DEG C, 55 DEG C and 60 DEG C.In order to ensure low temperature The effect of processing, residence time of low-temperature treatment can be 10min~600min, preferably 20min~300min, preferably 50min~70min.

In the present invention, pass through the condition of second evaporation and low-temperature treatment of control so that the second evaporation can be higher Evaporating temperature, closer to normal pressure evaporating pressure under carry out, avoid at a lower temperature evaporation when the low problem of efficiency, not only Evaporation efficiency is improved, and the energy consumption of evaporation process can be reduced, improves wastewater treatment speed.On this basis, low temperature The temperature control of processing is easier, and low-temperature treatment temperature can be under conditions of less than evaporating temperature (such as 45 DEG C or less) It is operated, is more conducive to the dissolving of sodium sulphate and the precipitation of sodium chloride.

In the present invention, the low-temperature treatment may be used various cooling systems commonly used in the art and carry out, such as It can select low-temperature treatment tank 55.Preferably, it can be provided with cooling-part in the low-temperature treatment tank 55, can is specifically Import the component of cooling water.By the cooling-part, the second concentrate in low-temperature treatment tank can be cooled down rapidly.It is preferred that Ground can be provided with mixing component in the low-temperature treatment tank 55, by the mixing component, can make in the second concentrate Solid-liquid distributed mutually, Temperature Distribution are uniform, and reaching makes sodium sulfate crystal fully dissolve, and the mesh that sodium chloride crystal is precipitated to greatest extent 's.

In the present invention, sodium chloride is made not crystallize precipitation in order to reach first evaporation, described second is precipitated when evaporating The purpose that can be dissolved in low-temperature process of sodium sulfate crystal, preferably make the condition of the first evaporation and low-temperature treatment full Foot：It is described first evaporation temperature 5 DEG C higher than the temperature of low-temperature treatment or more (with the evaporation thermometer of last 1st effective evaporator), It is preferred that high 20 DEG C or more, it is more preferably 35 DEG C high~90 DEG C, it is further preferably 35 DEG C high~70 DEG C, it is particularly preferably high by 50 DEG C~60 ℃.By the temperature of first evaporation and low-temperature treatment of control, so that sodium sulphate in the first evaporation is individually crystallized precipitation, make low-temperature treatment In sodium sulphate in the second evaporation sodium sulfate crystal and sodium chloride crystal that are precipitated can dissolve, to improve obtained sodium sulphate With the purity of sodium chloride crystal.

A preferred embodiment according to the present invention, the MVR vaporising devices 1 evaporate the second obtained steam containing ammonia In the 4th heat-exchanger rig 34 the second heat is carried out with the first mother liquor (or the first mother liquor and circulation fluid, mixed liquor of the second leacheate) It exchanges and obtains the second ammonium hydroxide.According to the present invention, after the second heat exchange, first mother liquor (or the first mother liquor and cycle The mixed liquor of liquid, the second leacheate) temperature be 50 DEG C~200 DEG C, further preferably 75 DEG C~184 DEG C, further it is excellent It is selected as 85 DEG C~102 DEG C~117 DEG C.

There is no particular limitation for 4th heat-exchanger rig 34, can use various heat exchangers commonly used in the art, Achieve the purpose that second steam containing ammonia is made to condense.Specifically, it can be jacketed type exchanger, plate heat exchanger, pipe Shell heat exchanger, screw heat exchange of heat pipe etc..The material of the heat exchanger can be specifically chosen as needed, such as due to two Secondary steam does not have corrosivity, preferably stainless steel spiral screwed tube heat exchanger to stainless steel.

In the present invention, the treatment fluid for the sodium chloride-containing crystal that the low-temperature treatment obtains obtains after second is separated by solid-liquid separation To sodium chloride crystal and the second mother liquor (i.e. second is separated by solid-liquid separation obtained liquid phase).Described second method being separated by solid-liquid separation is without spy Other restriction, such as can be selected from one or more in centrifugation, filtering and sedimentation.

According to the present invention, second separation of solid and liquid can (be, for example, centrifuge, belt by the second equipment for separating liquid from solid Filter, flame filter press etc.) it carries out.After described second is separated by solid-liquid separation, the second mother liquor that the second equipment for separating liquid from solid 92 obtains It is temporarily stored into the second mother liquor tank 54, and multi-effect evaporating device 2 can be returned and carry out the first evaporation again, can specifically pass through the 9th Second mother liquor is returned and is mixed to get pending waste water with catalyst production waste water before second of pH value is adjusted by circulating pump 79.Separately Outside, the impurity such as certain sulfate ion, free ammonia, hydroxide ion can be adsorbed by being difficult to avoid that on the sodium chloride crystal obtained, In order to remove the impurity of absorption, the peculiar smell of solid salt is reduced, corrosivity is reduced, improves the purity of the crystal, it is preferable that described Sodium chloride crystal water, the catalyst production waste water or sodium chloride solution carry out the second washing and drying.In order to avoid washing The dissolving of sodium chloride crystal in the process, it is preferable that the sodium chloride crystal is washed with sodium-chloride water solution.It is highly preferred that Sodium chloride and sodium sulphate reach simultaneously at the concentration of the sodium-chloride water solution preferably temperature corresponding to sodium chloride crystal to be washed To the concentration of sodium chloride in the aqueous solution of saturation.

It is separated by solid-liquid separation the mode washed with second as above-mentioned second, there is no particular limitation, and ability can be used for example The elutriation apparatus and solid-liquid separating equipment of domain routine, which combine, to carry out, can also be in the equipment for separating liquid from solid such as band filter of segmentation Upper progress.Preferably, second washing includes eluriating and/or eluting.For above-mentioned elutriation and elution, there is no particular limitation, It can be carried out by the method for this field routine.It is described elutriation and elution number there is no particular limitation, can be 1 time with On, the sodium chloride crystal of higher purity, preferably 2-4 times in order to obtain.During elutriation, made with the catalyst production waste water It does not recycle generally when liquid to eluriate, can be used with circulated in countercurrent when doing elutriation liquid using the cleaning solution of the second washing recycling. Before carrying out the elutriation, tentatively separation of solid and liquid is carried out preferably by way of sedimentation and obtains the slurries (liquid of sodium chloride-containing crystal Content is 35 mass % or less, which preferably carries out in the device well known in the art such as settling tank, settling tank).It washes in a pan During washing, relative to the slurries of 1 parts by weight sodium chloride-containing crystal, it is 1~20 parts by weight to eluriate the liquid used.Elution is preferred Using sodium-chloride water solution, (concentration of the sodium-chloride water solution is preferably chlorination at the temperature corresponding to sodium chloride crystal to be washed Sodium and sodium sulphate reach the concentration of sodium chloride in the aqueous solution of saturation simultaneously) it carries out.In order to further increase the effect of elutriation, obtain To the higher sodium chloride crystal of purity, in the case of preferred, the liquid that elution can be used to obtain is washed.Washing is produced Raw liquid, it is preferable that the catalyst production waste water eluriates second of pH value that liquid is back to before multi-effect evaporating device evaporation Before adjusting, water or sodium-chloride water solution cleaning solution are back to MVR vaporising devices, such as return to MVR by the tenth circulating pump 80 Vaporising device 1 carries out the second evaporation again.

A preferred embodiment according to the present invention, by the processing for the sodium chloride-containing crystal that low-temperature treatment obtains Liquid carries out first time elutriation, so with the catalyst production waste water after settling progress tentatively separation of solid and liquid in eluriating tank The liquid that is obtained when subsequent wash sodium chloride crystal is reused afterwards carry out second in another elutriation tank eluriate, it finally will be through The second equipment for separating liquid from solid is sent into after the slurries eluriated twice to be separated by solid-liquid separation, the crystal being separated by solid-liquid separation uses sodium chloride again (sodium chloride and sodium sulphate is simultaneously at a concentration of temperature corresponding to sodium chloride crystal to be washed of the sodium-chloride water solution for aqueous solution Reach the concentration of sodium chloride in the aqueous solution of saturation) it is eluted, and obtained liquid will be eluted back in eluriating for the second time As elutriation liquid.The purity of the washing process combined by above-mentioned elutriation and elution, the sodium chloride crystal not only made improves, And introducing cleaning solution that will not be excessive, improves the efficiency of wastewater treatment.

A preferred embodiment according to the present invention, first steam containing ammonia is cold by first heat exchange Remaining tail gas is coagulated to discharge after removing ammonia；Second steam containing ammonia is condensed into remaining tail gas by second heat exchange It is discharged after removing ammonia.First steam containing ammonia condenses remaining tail gas, that is, second heat exchange by first heat exchange The tail gas that device 32 is discharged, second steam containing ammonia condense the remaining heat exchange of tail gas the i.e. the 4th dress by second heat exchange Set the tail gas of 34 discharges.By the way that above-mentioned tail gas is removed ammonia, the pollutant load in emission can be further decreased, makes it can With direct emission.

As the mode except ammonia, can be absorbed with tail gas absorber 83.The tail gas absorber 83 is without spy Other restriction can be various absorption towers commonly used in the art, such as tray absorption columns, packed absorber, falling film absorption Tower or void tower etc..There is recirculated water in the tail gas absorber 83, the recirculated water is under the action of the 4th circulating pump 74 in tail gas It is recycled in absorption tower 83, water can also be added to tail gas absorber 83 from circulating water pool 82 by third circulating pump 73, recycled Pond 82 can add fresh water, while can reduce by the temperature and ammonia content of 81 work water of vacuum pump.The tail gas absorber The type of flow of 83 inner exhaust gas and recirculated water can adverse current also can cocurrent, preferably adverse current.The recirculated water can be by additional Fresh water is supplemented.In order to ensure that tail gas fully absorbs, dilute sulfuric acid can also be further added in the tail gas absorber 83, To absorb a small amount of ammonia in tail gas etc..The recirculated water can be used as ammonium hydroxide or ammonium sulfate to be back to after absorbing tail gas It produces or sells.As the mode that above-mentioned tail gas is passed through to tail gas absorber 83, can be carried out by vacuum pump 81.

In the present invention, there is no particular limitation for the catalyst production waste water, as long as containing NH₄ ⁺、SO₄ ^2-、Cl^-And Na⁺ Waste water.In addition, the method for the present invention is particularly suitable for the processing of high-salt wastewater.Catalyst production as the present invention is useless Water is specifically as follows the waste water from molecular sieve, aluminium oxide or oil refining catalyst production process, and can also be will be from molecule The waste water of sieve, aluminium oxide or oil refining catalyst production process carries out the waste water after following removal of impurities and concentration.It will preferably come from and divide The waste water of son sieve, aluminium oxide or oil refining catalyst production process carries out the waste water after following removal of impurities and concentration.

As the NH in the catalyst production waste water₄ ⁺Can be 8mg/L or more, preferably 300mg/L or more.

As the Na in the catalyst production waste water⁺Can be 510mg/L or more, preferably 1g/L or more, more preferably For 2g/L or more, further preferably 4g/L or more, further preferably 8g/L or more, further preferably 16g/L or more, into One step is preferably 32g/L or more, further preferably 40g/L or more, further preferably 50g/L or more, further preferably 60g/L or more.

As the SO in the catalyst production waste water₄ ^2-Can be 1g/L or more, preferably 2g/L or more, more preferably 4g/L or more, further preferably 8g/L or more, further preferably 16g/L or more, further preferably 32g/L or more, into One step is preferably 40g/L or more, further preferably 50g/L or more, further preferably 60g/L or more, further preferably 70g/L or more.

As the Cl in the catalyst production waste water^-Can be 970mg/L or more, more preferably 2g/L or more, into one Step is preferably 4g/L or more, further preferably 8g/L or more, further preferably 16g/L or more, further preferably 32g/L More than, further preferably 40g/L or more, further preferably 50g/L or more, further preferably 60g/L or more.

The NH contained in the catalyst production waste water₄ ⁺、SO₄ ^2-、Cl^-And Na⁺The upper limit there is no particular limitation.From useless Water is easy from the point of view of starting with, SO in waste water₄ ^2-、Cl^-And Na⁺The upper limit be respectively 200g/L hereinafter, preferably 150g/L with Under；NH in waste water₄ ⁺For 50g/L hereinafter, preferably 30g/L or less.

From the efficiency for improving the first evaporation, from the point of view of the energy consumption for reducing processing procedure, relative in ammonium salt-containing waste water The SO contained₄ ^2-, the Cl in ammonium salt-containing waste water^-The lower content the better, for example, relative to containing in 1 mole of ammonium salt-containing waste water SO₄ ^2-, the Cl that contains in the ammonium salt-containing waste water^-For 30 moles hereinafter, preferably 20 moles hereinafter, more preferably 15 moles Hereinafter, further preferably 10 moles or less.And from the point of view of practicability, relative in 1 mole of ammonium salt-containing waste water The SO contained₄ ^2-, the Cl that contains in the ammonium salt-containing waste water^-Preferably 0.1 mole or more, more preferably 0.5 mole or more, into One step is preferably 1 mole or more, such as 0.5-10 moles, preferably 1-8 moles, preferably 1-6 moles.By the way that described ammonium will be contained The SO contained in salt waste water₄ ^2-And Cl^-Molar ratio be limited to above range, most of water can be steamed in the first evaporation, The circulation fluid scale of construction in system for handling is reduced, it is energy saving, keep processing procedure more economical.

In the present invention, the inorganic ion contained in the catalyst production waste water is in addition to NH₄ ⁺、SO₄ ^2-、Cl^-And Na⁺ In addition, Mg can also be contained²⁺、Ca²⁺、K⁺、Fe³⁺, the inorganic ions such as rare earth element ion, Mg²⁺、Ca²⁺、K⁺、Fe³⁺, rare earth member The respective content of the inorganic ions such as plain ion is preferably 100mg/L hereinafter, more preferably 50mg/L is hereinafter, further preferably 10mg/L is not hereinafter, contain other inorganic ions particularly preferably.It, can by controlling other inorganic ions in above range To further increase the purity of finally obtained sodium sulfate crystal and sodium chloride crystal.In order to reduce the catalyst production waste water In other inorganic ions content, preferably carry out following removal of impurities.

The TDS of the catalyst production waste water can be 1.6g/L or more, preferably 4g/L or more, more preferably 8g/L with On, further preferably 16g/L or more, further preferably 32g/L or more, further preferably 40g/L or more are further excellent It is selected as 50g/L or more, further preferably 60g/L or more, further preferably 100g/L or more, further preferably 150g/L More than, further preferably 200g/L or more.

In the present invention, the pH value of the catalyst production waste water is preferably 4~8, and for example, 6~7.

In addition, due to catalyst production waste water COD concentration when may block up film, in evaporative crystallization when influence salt purity With color and luster etc., the COD of the catalyst production waste water it is more fewer better (preferably 20mg/L hereinafter, more preferably 10mg/L with Under), such as bioanalysis, advanced oxidation processes progress specifically preferably can be used, in COD contents by oxidation removal in pretreatment When very high preferably use it is oxidizing, the oxidant for example can be Fenton reagent.

In the present invention, in order to reduce the concentration impurity ion in catalyst production waste water, ensure the continuous of processing procedure Stablize and carry out, reduces equipment operation maintenance cost, the catalyst production waste water is before using the processing of the processing method of the present invention Preferably through removal of impurities.Preferably, the one kind of the removal of impurities in separation of solid and liquid, chemical precipitation, absorption, ion exchange and oxidation Or it is a variety of.

Can be filtering, centrifugation, sedimentation etc. as the separation of solid and liquid；Can be to adjust as the chemical precipitation PH, carbonate deposition, magnesium salts precipitation etc.；Can be physical absorption and/or chemisorption, specific absorption as the absorption Agent can select activated carbon, silica gel, aluminium oxide, molecular sieve, natural clay etc.；As the ion exchange, strong acid may be used Any one in property resin cation, acidulous cation resin；As the oxidation, may be used commonly used in the art Various oxidants, such as ozone, hydrogen peroxide, potassium permanganate, in order to avoid introducing new impurity, it is preferred to use ozone, dioxygen Water etc..

Specific removal of impurities mode can be specifically chosen according to the dopant species contained in the catalyst production waste water.For Suspended matter can select solid-liquid isolation method to clean；For inorganic matter and organic matter, chemical precipitation method, ion exchange can be selected Method, absorption method removal of impurities, such as Subacidity cation exchange process, active carbon adsorption etc.；For organic matter, absorption may be used And/or the mode of oxidation cleans, wherein preferably ozone biological activated carbon adsorption and oxidation method.One according to the present invention preferred Embodiment, catalyst production waste water is successively by filtering, Subacidity cation exchange process, ozone biological activated carbon adsorption and oxidation Method cleans.By above-mentioned dedoping step, most suspended substances, hardness, silicon and organic matter can be removed, reduces device fouling Risk ensures wastewater treatment process continuous and steady operation.

It in the present invention, can be in the processing method using the present invention for the lower catalyst production waste water of salt content Before processing (preferably after above-mentioned removal of impurities), made required by the catalyst production waste water that salt content reaches the present invention by concentrating Range.Preferably, it is described concentration selected from ED films concentration and/or it is reverse osmosis；It is highly preferred that it is described be concentrated by ED films concentration and There is no particular limitation for the sequencing of reverse osmosis progress, the ED films concentration and reverse osmosis progress.ED films concentration and anti- The mode that this field routine may be used in infiltration processing unit and condition carries out, and can specifically be selected according to the case where pending waste water It selects.Specifically, it is concentrated as the ED films, unidirectional electrodialysis system or pole-reversing electroosmosis system can be selected to carry out；As institute State it is reverse osmosis, can select rolled film, plate membrane, dish tubular membrane, vibrating membrane or combinations thereof carry out.It can be carried by the concentration The efficiency of high catalyst production wastewater treatment avoids energy waste caused by largely evaporating.

In the preferred embodiment of the present invention, catalyst production waste water is the waste water in process of producing molecular sieve It cleans, and passes through by chemical precipitation, filtering, Subacidity cation exchange process and ozone biological activated carbon adsorption and oxidation method ED films concentrate and the waste water after reverse osmosis concentration.

Condition as above-mentioned chemical precipitation is preferably：Using sodium carbonate as inorganic agent, relative to 1 mole of calcium in waste water 1.2-1.4 mole of either sodium carbonate is added in ion, and the pH for adjusting waste water is more than 7, and reaction temperature is 20-35 DEG C, reaction time 0.5- 4h。

Condition as above-mentioned filtering is preferably：Filter element is situated between more using the double-layer filter material of anthracite and quartz sand composition Mass filter, anthracite granule size used are 0.7-1.7mm, quartz sand particle size 0.5-1.3mm, filtering velocity 10-30m/h.Filter The regeneration method of " gas backwash-gas and water backwash-water backwashing " is used to carry out media regeneration, regeneration period 10- after expecting use 15h。

Condition as above-mentioned Subacidity cation exchange process is preferably：PH value range is 6.5-7.5；Temperature≤40 DEG C, Resin layer height is 1.5-3.0m, regenerated liquid HCl concentration：4.5-5 mass %；Regenerant consumption (based on 100%), 50-60kg/ m³Wet resin；Regenerated liquid HCl flow velocitys are 4.5-5.5m/h, and regeneration time of contact is 35-45min；It is 18-22m/h just to wash flow velocity, It is 2-30min just to wash the time；Operation flow velocity is 15-30m/h；Langfang sanat can be used for example in acid cation exchange resin Chemical Co., Ltd., SNT board D113 acid cation exchange resins.

Condition as above-mentioned ozone biological activated carbon adsorption and oxidation method is preferably：The ozone residence time is 50-70min, Empty bed filtering velocity is 0.5-0.7m/h.

As above-mentioned ED films concentration condition be preferably：Electric current 145-155A, voltage 45-65V.It for example can be with as ED films For the ED films of Japanese A Sitong companies production.

It is preferably as above-mentioned reverse osmosis condition：Operating pressure 5.4-5.6MPa, 25-35 DEG C of inflow temperature, pH value are 6.5-7.5.It is for example carried out using the sea water desalination membrane TM810C that blue star Toray produces as reverse osmosis membrane.

It according to the present invention, when proceeding by wastewater treatment, can directly be gone into operation using catalyst production waste water, if catalysis The ion concentration of agent production waste water meets the condition of the present invention, the first evaporation can be first carried out with condition according to the invention and carried out again Second evaporation；If the ion concentration of catalyst production waste water is unsatisfactory for the condition of the present invention, can control the first evaporation makes the In one concentrate then the first concentrate is carried out the second evaporation and low-temperature treatment, obtained by the concentration of sodium chloride close to concentration is precipitated It to treatment fluid and is separated by solid-liquid separation and obtains sodium chloride crystal and the second mother liquor, then the second mother liquor and the catalyst production waste water are mixed It closes and obtains sodium sulphate crystalline substance to adjust the ion concentration of pending waste water to carry out the first evaporation after range of the presently claimed invention again Body.It can also use sodium sulphate and sodium chloride that the ion concentration in pending waste water is adjusted in the starting stage, only certainly The pending waste water is set to meet in the present invention to SO in pending waste water₄ ^2-、Cl^-Requirement.

The present invention will be described in detail by way of examples below.

In following embodiment, catalyst production waste water be process of producing molecular sieve in waste water successively pass through chemical precipitation, Filtering, Subacidity cation exchange process and ozone biological activated carbon adsorption and oxidation method clean, and pass through ED films successively and concentrate Waste water after being concentrated with reverse osmosis.

Embodiment 1

As shown in Figure 1, by catalyst production waste water (120g/L containing NaCl, Na₂SO₄ 50g/L、NH₄Cl 52g/L、 (NH₄)₂SO₄22.02g/L, pH 6.7) with inlet amount it is 5m³The speed of/h is sent in the pipeline of processing system, in waste water The sodium hydrate aqueous solution that a concentration of 45.16 mass % is imported in conveyance conduit carries out pH value adjusting, then mixed with the second mother liquor Conjunction obtains the pending waste water (SO wherein contained₄ ^2-And Cl^-Molar ratio be 1：7.0315), it is being sent to the first heat-exchanger rig 31, it is filled by the measurement of the first pH value before third heat-exchanger rig 33 and the 5th heat-exchanger rig 35 (being titanium alloy plate heat exchanger) It sets 61 (pH meters) and (measured value 9) is monitored to the pH value after adjusting, then pump 71 by pending waste water by first circulation A part (3m³/ h) it is sent into the first heat-exchanger rig 31, carrying out the first heat exchange with the first liquid of steam condensation containing ammonia of recycling makes Pending waste water is warming up to 82 DEG C, another part (2.5m³/ h) it is sent into third heat-exchanger rig 33, the second steam containing ammonia with recycling Condensation water, which carries out the first heat exchange, makes pending waste water be warming up to 99 DEG C, and rest part is sent into the 5th heat-exchanger rig 35, with second Concentrate, which carries out the first heat exchange, makes pending waste water be warming up to 104 DEG C, and multiple-effect is sent into after then converging pending waste water and is steamed Transmitting apparatus 2；Import a concentration of 45.16 mass %'s in the pipeline of multi-effect evaporating device 2 above-mentioned pending waste water to be sent to Sodium hydrate aqueous solution carries out second of pH value adjusting, and by the second pH value measuring device 62 (pH meter) to the pH value after adjusting It is monitored (measured value 11), the pending waste water after pH value is adjusted is sequentially sent to each effect of multi-effect evaporating device 2 Evaporator is evaporated, and obtains the first concentrate of the first steam containing ammonia and sulfur acid sodium crystal.The multi-effect evaporating device 2 by 1st effective evaporator 2a, 2nd effect evaporator 2b, third effect evaporator 2c and fourth evaporator 2d (are forced-circulation evaporation Device) composition.Wherein, the evaporation conditions of multi-effect evaporating device 2 such as the following table 1：

Table 1

Respectively by the 17th circulating pump 87, the 16th circulating pump 86 and the 15th circulating pump 85 by preceding 1st effective evaporator 1st effective evaporator after the liquid that (1st effective evaporator 2a, 2nd effect evaporator 2b and third effect evaporator 2c) evaporation obtains is sent into (2nd effect evaporator 2b, third effect evaporator 2c and fourth evaporator 2d), first that rear 1st effective evaporator is evaporated 1st effective evaporator carries out heat exchange and obtains the first ammonium hydroxide before steam containing ammonia is passed through, and further in the first heat-exchanger rig 31 with Pending waste water carries out heat exchange, and the first steam containing ammonia evaporated in 1st effective evaporator 2a is in the second heat-exchanger rig 32 Heat exchange is carried out with cooling water (catalyst production waste water) and obtains the first ammonium hydroxide, and the merging of the first ammonium hydroxide is stored in the first ammonium hydroxide In storage tank 51.Heating steam (life steam i.e. commonly used in the art) is passed through in fourth evaporator 2d, heating steam exists The condensation water obtained after being condensed in fourth evaporator 2d is for preparing washing solution.Pass through what is be arranged on multi-effect evaporating device 2 The degree that densitometer pair first evaporates is monitored, and controls a concentration of 0.99352X of the first evaporation concentrated solution sodium chloride (306.8g/L).Above-mentioned multi-effect evaporating device 2 is evaporated the first obtained concentrate to crystallize in brilliant liquid collecting tank 56, is tied Brilliant temperature is 105 DEG C, and crystallization time 5min obtains the magma of sulfur acid sodium crystal.

The magma of above-mentioned sulfur acid sodium crystal is sent into the first equipment for separating liquid from solid 91 (centrifuge) and carries out the first solid-liquid point From obtaining 6.817m per hour³Contain NaCl 306.8g/L, Na₂SO₄ 52.6g/L、NaOH 1.83g/L、NH₃ 0.32g/L The first mother liquor, be temporarily stored into the first mother liquor tank 53, be separated by solid-liquid separation gained solid sodium sulfate (obtain aqueous 15 mass % per hour Sulfate crystal filter cake 429.87kg, the wherein content of sodium chloride is 6.0 mass % or less) with dry with sulfate crystal filter cake The equal 52.6g/L metabisulfite solutions elution of matrix amount, it is dry in drying machine, it is (pure that sodium sulphate 365.38kg is obtained per hour Degree is 99.4 weight %), cleaning solution liquid is recycled to before second of pH is adjusted by the 8th circulating pump 78 and is carried out with pending waste water Then mixing is fed again into multi-effect evaporating device 2 and carries out the first evaporation.

The first mother liquor in above-mentioned first mother liquor tank 53 is sent into MVR vaporising devices 1 by the 6th circulating pump 76 and carries out the Two evaporations, obtain the second concentrate of the second steam containing ammonia and sulfur acid sodium crystal and sodium chloride crystal, condition such as upper table 1. The MVR vaporising devices 1 are evaporated to the second obtained steam containing ammonia after the compression of compressor 102 after (18 DEG C of temperature rise), It exchanges heat in the 4th heat-exchanger rig 34 with the first mother liquor, then exchanges heat in third heat-exchanger rig 33 with the pending waste water in part, obtain the Two ammonium hydroxide are stored in the second tank used for storing ammonia 52.In order to improve the solid content in MVR vaporising devices 1, by MVR vaporising devices 1 Partially liq after middle evaporation is fed again into MVR vaporising devices 1 by the 7th circulating pump 77 as circulation fluid and carries out the second evaporation (reflux ratio 36.8).The degree evaporated by the mass flowmenter pair second being arranged on MVR vaporising devices 1 is monitored, and is controlled The evaporation capacity of the second evaporation of system is 2.621m³/ h (is equivalent to a concentration of 0.976Y of sodium sulphate in control process liquid, i.e. 82.2g/ L).After first mother liquor evaporates in MVR vaporising devices 1, the second concentrate of obtained sulfur acid sodium crystal and sodium chloride crystal Low-temperature treatment is carried out in low-temperature treatment tank 55, temperature is 25 DEG C, and residence time 50min obtains the processing of sodium chloride-containing crystal Liquid.

The treatment fluid of above-mentioned sodium chloride-containing crystal is sent into the second equipment for separating liquid from solid 92 (centrifuge) to be separated by solid-liquid separation, 4.198m is obtained per hour³Contain NaCl 279.5g/L, Na₂SO₄ 82.2g/L、NaOH 2.86g/L、NH₃The of 0.02g/L Two mother liquors are temporarily stored into the second mother liquor tank 54.Second mother liquor is all recycled to waste water delivery pipe by the 9th circulating pump 79 Road is mixed to get pending waste water with catalyst production waste water.It is separated by solid-liquid separation gained solid sodium chloride and (obtains water content per hour For the sodium chloride crystalli-zation cake 1044.04kg of 15 mass %, wherein the content of sodium sulphate is 5.2 mass % or less) it uses and chlorination It is dry in drying machine after the equal 279.5g/L sodium chloride solutions elution of sodium butt quality, sodium chloride is obtained per hour 887.43kg (purity is 99.4 weight %), after cleaning solution is back to the heat exchange of the 4th heat-exchanger rig 34 by the tenth circulating pump 80, It is back to MVR vaporising devices 1.

In addition, the second heat-exchanger rig 32 and the tail gas of the 4th heat-exchanger rig 34 discharge introduce tail gas absorption by vacuum pump 81 Tower 83 is absorbed, and recirculated water is connected in tail gas absorber 83, the recirculated water is under the action of the 4th circulating pump 74 in tail gas It is recycled in absorption tower 83, while water is added to tail gas absorber 83 from circulating water pool 82 by third circulating pump 73, and Fresh water is added in circulating water pool 82, reduces by the temperature and ammonia content of 81 work water of vacuum pump.In the tail gas absorber 83 It is further passed through dilute sulfuric acid, to absorb ammonia in tail gas etc..In addition, the initial period of MVR evaporations, is 143.3 by temperature DEG C steam started.

In the present embodiment, the ammonium hydroxide 3.046m of a concentration of 3.44 mass % is obtained in the first tank used for storing ammonia 51 per hour³, The ammonium hydroxide 2.621m of a concentration of 0.081 mass % is obtained in second tank used for storing ammonia 52 per hour³, ammonium hydroxide can be back to molecular sieve Production process.

Embodiment 2

The processing of catalyst production waste water is carried out according to the method for embodiment 1, unlike：To contain NaCl 70g/L, Na₂SO₄ 168g/L、NH₄Cl 20g/L、(NH₄)₂SO₄The catalyst production waste water that 48.79g/L, pH are 6.7 is handled, and is obtained To pending waste water in the SO that contains₄ ^2-And Cl^-Molar ratio be 1：7.5336.Hot friendship is carried out by the first heat-exchanger rig 31 The temperature for changing rear waste water is 75 DEG C, and the temperature by pending waste water after the progress heat exchange of third heat-exchanger rig 33 is 105 DEG C, is led to Cross the 5th heat-exchanger rig 35 carry out heat exchange after pending waste water temperature be 106 DEG C.Multi-effect evaporating device 2 and MVR evaporation dresses Set 1 evaporation conditions such as the following table 2.The temperature of low-temperature treatment is 30 DEG C, residence time 65min.

Table 2

First equipment for separating liquid from solid 91 obtains the sulfate crystal filter cake 1285.70kg of aqueous 14 mass % per hour, most Obtain sodium sulphate 1105.70kg per hour eventually (purity is 99.5 weight %)；3.548m is obtained per hour³A concentration of NaCl 307g/L、Na₂SO₄ 52.73g/L、NaOH 1.67g/L、NH₃The first mother liquor of 0.49g/L.

Second equipment for separating liquid from solid 92 obtains the sodium chloride crystalli-zation cake 530.34kg that water content is 14 mass % per hour, It is final to obtain sodium chloride 456.09kg per hour (purity is 99.5 weight %)；2.418m is obtained per hour³A concentration of NaCl 283.3g/L、Na₂SO₄ 79.8g/L、NaOH 2.53g/L、NH₃The second mother liquor of 0.037g/L.

In the present embodiment, the ammonium hydroxide 4.389m of a concentration of 2.06 mass % is obtained in the first tank used for storing ammonia 51 per hour³, The ammonium hydroxide 1.373m of a concentration of 0.13 mass % is obtained in second tank used for storing ammonia 52 per hour³, ammonium hydroxide can be back to molecular sieve Production process.

Embodiment 3

The processing of catalyst production waste water is carried out according to the method for embodiment 1, unlike：To contain NaCl 100g/L, Na₂SO₄ 102g/L、NH₄Cl 22g/L、(NH₄)₂SO₄The catalyst production waste water that 22.81g/L, pH are 6.6 is handled, and is obtained To pending waste water in the SO that contains₄ ^2-And Cl^-Molar ratio be 1：5.1991.Hot friendship is carried out by the first heat-exchanger rig 31 The temperature for changing rear waste water is 70 DEG C, and the temperature by pending waste water after the progress heat exchange of third heat-exchanger rig 33 is 105 DEG C, is led to Cross the 5th heat-exchanger rig 35 carry out heat exchange after pending waste water temperature be 105 DEG C.Multi-effect evaporating device 2 and MVR evaporation dresses Set 1 evaporation conditions such as the following table 3.The temperature of low-temperature treatment is 35 DEG C, residence time 70min.

Table 3

First equipment for separating liquid from solid 91 obtains the sulfate crystal filter cake 745.20kg of aqueous 15 mass % per hour, finally Sodium sulphate 633.41kg (purity is 99.4 weight %) is obtained per hour obtains 6.950m per hour³A concentration of NaCl 305.8g/ L、Na₂SO₄ 53.84g/L、NaOH 2.2g/L、NH₃The first mother liquor of 0.18g/L.

Second equipment for separating liquid from solid 92 obtains the sodium chloride crystalli-zation cake 728.91kg that water content is 15 mass % per hour, It is final to obtain sodium chloride 619.57kg per hour (purity is 99.5 weight %)；5.222m is obtained per hour³A concentration of NaCl 289.1g/L、Na₂SO₄ 71.2g/L、NaOH 2.91g/L、NH₃The second mother liquor of 0.014g/L.

In the present embodiment, the ammonium hydroxide 3.692m of a concentration of 1.68 mass % is obtained in the first tank used for storing ammonia 51 per hour³, The ammonium hydroxide 1.826m of a concentration of 0.066 mass % is obtained in second tank used for storing ammonia 52 per hour³, ammonium hydroxide can be back to molecular sieve Production process.

The preferred embodiment of the present invention has been described above in detail, still, during present invention is not limited to the embodiments described above Detail can carry out a variety of simple variants to technical scheme of the present invention within the scope of the technical concept of the present invention, this A little simple variants all belong to the scope of protection of the present invention.

It is further to note that specific technical features described in the above specific embodiments, in not lance In the case of shield, it can be combined by any suitable means.In order to avoid unnecessary repetition, the present invention to it is various can The combination of energy no longer separately illustrates.

In addition, various embodiments of the present invention can be combined randomly, as long as it is without prejudice to originally The thought of invention, it should also be regarded as the disclosure of the present invention.

Claims

1. a kind of processing method of catalyst production waste water, the catalyst production waste water contain NH₄ ⁺、SO₄ ^2-、Cl^-And Na⁺, special Sign is that this approach includes the following steps,

1) pending waste water is passed through successively in each effect evaporator of multi-effect evaporating device and carries out the first evaporation, obtained first and contain ammonia First concentrate of steam and sulfur acid sodium crystal, the pending waste water contain the catalyst production waste water；

2) the first concentrate of the sulfur acid sodium crystal is carried out first to be separated by solid-liquid separation, and obtained liquid is separated by solid-liquid separation by first It is mutually passed through MVR vaporising devices and carries out the second evaporation, obtain the second steam containing ammonia and sulfur acid sodium crystal and sodium chloride crystal Second concentrate；

3) the second concentrate of the sulfur acid sodium crystal and sodium chloride crystal is subjected to low-temperature treatment, keeps sodium sulfate crystal molten Solution, obtains the treatment fluid of sodium chloride-containing crystal；

Wherein, before the pending waste water is passed through multi-effect evaporating device, the pH value for adjusting the pending waste water is more than 9；

Before the first steam containing ammonia that the rear 1st effective evaporator of the multi-effect evaporating device evaporates is passed through in 1st effective evaporator, The pending waste water and the first steam counter-flow containing ammonia heat exchange；

First evaporation makes sodium chloride not crystallize precipitation；

Relative to the SO contained in 1 mole of pending waste water₄ ^2-, the Cl that contains in the pending waste water^-For 14 moles with Under.

2. according to the method described in claim 1, wherein, the pending waste water is the catalyst production waste water；Alternatively, institute State the liquid phase that pending waste water contains the catalyst production waste water and second separation of solid and liquid obtains；

Preferably, relative to the SO contained in 1 mole of pending waste water₄ ^2-, the Cl that contains in the pending waste water^-For 13.8 mole or less；

Preferably, before the pending waste water is passed through multi-effect evaporating device, the pH value for adjusting the pending waste water is big In 10.8；

Preferably, the pH value for adjusting the pending waste water is carried out using NaOH.

3. method according to claim 1 or 2, wherein first evaporation makes the concentration of sodium chloride in the first concentrate For X or less, wherein X is chlorination when sodium sulphate and sodium chloride reach saturation in the first concentrate under conditions of first evaporates The concentration of sodium；

Preferably, second evaporation makes a concentration of Y or less of sodium sulphate in the treatment fluid, wherein Y is in low-temperature treatment Under the conditions of, the concentration of sodium sulphate when sodium sulphate and sodium chloride reach saturation in treatment fluid；

Preferably, first evaporation makes a concentration of 0.95X-0.999X of sodium chloride in the first concentrate；

Preferably, second evaporation makes a concentration of 0.9Y-0.99Y of sodium sulphate in the treatment fluid；

It is highly preferred that second evaporation makes a concentration of more preferably 0.95Y-0.98Y of sodium sulphate in the treatment fluid.

4. according to the method described in any one of claim 1-3, wherein it is described first evaporation condition include：Temperature is 35 DEG C or more, pressure is -95kPa or more；

Preferably, the condition of first evaporation includes：Temperature is 45 DEG C~365 DEG C, and pressure is -95kPa~18110kPa；

Preferably, the condition of first evaporation includes：Temperature is 60 DEG C~365 DEG C, and pressure is -87kPa~18110kPa；

Preferably, the condition of first evaporation includes：Temperature is 75 DEG C~175 DEG C, and pressure is -73kPa~653kPa；

Preferably, the condition of first evaporation includes：Temperature is 80 DEG C~130 DEG C, and pressure is -66kPa~117kPa；

Preferably, the condition of first evaporation includes：Temperature is 95 DEG C~115 DEG C, and pressure is -37kPa~33kPa.

5. according to the method described in any one of claim 1-3, wherein it is described second evaporation condition include：Temperature is 35 DEG C or more, pressure is -95kPa or more；

Preferably, the condition of second evaporation includes：Temperature is 45 DEG C~175 DEG C, and pressure is -95kPa~18110kPa；

Preferably, the condition of second evaporation includes：Temperature is 60 DEG C~175 DEG C, and pressure is -87kPa~18110kPa；

Preferably, the condition of second evaporation includes：Temperature is 75 DEG C~175 DEG C, and pressure is -73kPa~653kPa；

Preferably, the condition of second evaporation includes：Temperature is 80 DEG C~130 DEG C, and pressure is -66kPa~117kPa；

Preferably, the condition of second evaporation includes：Temperature is 95 DEG C~110 DEG C, and pressure is -37kPa~12kPa.

6. according to the method described in any one of claim 1-3, wherein the condition of the low-temperature treatment includes：Temperature is 13 DEG C~100 DEG C, preferably 15 DEG C~45 DEG C, more preferably 15 DEG C~35 DEG C, further preferably 17.9 DEG C~35 DEG C.

7. the method according to claim 4 or 6, wherein the temperature of first evaporation is 5 DEG C higher than the temperature of low-temperature treatment More than, it is preferably high 20 DEG C or more, more preferably 35 DEG C high~90 DEG C.

8. according to the method described in claim 1, wherein, before the pending waste water is passed through the multi-effect evaporating device, The pending waste water is subjected to the first heat exchange with the first ammonium hydroxide obtained from the multi-effect evaporating device；

Preferably, the first steam containing the ammonia 1st effective evaporator of the multi-effect evaporating device obtained and the pending waste water It carries out the first heat exchange and obtains the first ammonium hydroxide；

Preferably, before carrying out first heat exchange, the pH value for adjusting pending waste water is more than 7；

Preferably, first steam containing ammonia remaining tail gas is condensed by first heat exchange to discharge after removing ammonia.

9. according to the method described in claim 1, wherein, the second steam containing ammonia and institute that the MVR vaporising devices evaporate The liquid phase that the first separation of solid and liquid obtains is stated to carry out the second heat exchange and obtain the second ammonium hydroxide；

Preferably, second steam containing ammonia remaining tail gas is condensed by second heat exchange to discharge after removing ammonia.

10. according to the method described in any one of claim 1-9, this method further includes by the of the sulfur acid sodium crystal One concentrate obtains sodium sulfate crystal after first is separated by solid-liquid separation；

Preferably, this method further includes being washed to obtained sodium sulfate crystal.

11. according to the method described in any one of claim 1-9, this method further includes by the place of the sodium chloride-containing crystal Reason liquid obtains sodium chloride crystal after second is separated by solid-liquid separation；

Preferably, this method further includes being washed to obtained sodium chloride crystal.

12. according to the method described in any one of claim 1-9, wherein NH in the catalyst production waste water₄ ⁺For 8mg/ L or more, SO₄ ^2-For 1g/L or more, Cl^-For 970mg/L or more, Na⁺For 510mg/L or more；

Preferably, the catalyst production waste water is the waste water from molecular sieve, aluminium oxide or oil refining catalyst production process；

Preferably, this method further includes that the catalyst production waste water is cleaned and concentrated.