CN108726611A

CN108726611A - A kind of processing method of catalyst production waste water

Info

Publication number: CN108726611A
Application number: CN201710265681.8A
Authority: CN
Inventors: 殷喜平; 李叶; 顾松园; 王涛; 苑志伟; 陈玉华; 张志民; 高晋爱
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: CN108726611B

Abstract

The present invention relates to sewage treatment fields, disclose a kind of processing method of catalyst production waste water, which contains NH⁴⁺、SO₄ ^2‑、Cl^‑And Na⁺, this approach includes the following steps, 1) and it pending waste water is passed through the first MVR vaporising devices carries out the first evaporation and obtain the first concentrate of the first steam containing ammonia and sulfur acid sodium crystal；2) the first concentrate of the sulfur acid sodium crystal is carried out first to be separated by solid-liquid separation, and the liquid phase that the first separation of solid and liquid obtains is passed through the second evaporation of progress in the 2nd MVR vaporising devices and obtains the second concentrate of the second steam containing ammonia and sulfur acid sodium crystal and sodium chloride crystal；3) the second concentrate of the sulfur acid sodium crystal and sodium chloride crystal 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, which contains NH₄ ⁺、SO₄ ^2-、Cl^-And Na⁺, this approach includes the following steps,

1) pending waste water is passed through the first evaporation of the first MVR vaporising devices progress and obtains the first steam containing ammonia and sulfur acid First concentrate of 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 in the 2nd MVR vaporising devices carry out second evaporation, obtain the second steam containing ammonia and sulfur acid sodium crystal and chlorine Change the second concentrate of sodium crystal；

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 the first MVR vaporising devices, the pH of the pending waste water is adjusted Value is more than 9；First evaporation makes sodium chloride not crystallize precipitation；Relative to the SO contained in 1 mole of pending waste water₄ ^2-, The Cl contained 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.

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, the 2nd MVR vaporising devices 33, third heat-exchanger rig

2, the first MVR vaporising devices 34, the 4th heat-exchanger rig

31, the first heat-exchanger rig 35, the 5th heat-exchanger rig

32, the second heat-exchanger rig 51, the first tank used for storing ammonia

52, the second tank used for storing ammonia 77, the 7th circulating pump

53, the first mother liquor tank 78, the 8th circulating pump

54, the second mother liquor tank 79, the 9th circulating pump

55, low-temperature treatment tank 80, the tenth circulating pump

61, the first pH value measuring device 81, vacuum pump

62, the second pH value measuring device 82, circulating water pool

71, first circulation pump 83, tail gas absorber

72, second circulation pumps the 91, first equipment for separating liquid from solid

73, third circulating pump 92, the second equipment for separating liquid from solid

74, the 4th circulating pump 101, the first compressor

76, the 6th circulating pump 102, the second 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 the first evaporation of the first MVR vaporising devices 2 progress and obtains the first steam containing ammonia and sulfur-bearing First concentrate of sour 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 in the 2nd MVR vaporising devices 1 carry out second evaporation, obtain the second steam containing ammonia and sulfur acid sodium crystal and chlorine Change the second concentrate of sodium crystal；

Wherein, before the pending waste water is passed through the first MVR vaporising devices 2, the pending waste water is adjusted PH value is more than 9；First evaporation makes sodium chloride not crystallize precipitation；Relative to what is contained in 1 mole of pending waste water SO₄ ^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 the first MVR vaporising devices 2, the pending waste water is adjusted PH value be 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, Preferably 13.5 hereinafter, more preferable 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, more preferably 13.75 moles hereinafter, further preferably 13.5 moles hereinafter, further preferably 13 rub You are hereinafter, be still more preferably 12 moles hereinafter, being still more preferably 11 moles hereinafter, being still more preferably 10.5 to rub You are 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.By by SO₄ ^2-And Cl^-Molar ratio control in above range, sodium sulphate can be made to be precipitated and chlorination in the first evaporation Sodium is not precipitated, to achieve the purpose that efficiently separate sodium sulphate.It, in the present invention can also will be in addition, as above described below Thus the second Recycling Mother Solution obtained in second evaporation process is come to the first evaporation to the SO in pending waste water₄ ^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 the first MVR vaporising devices 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 pressure is the pressure in terms of gauge pressure.

In the present invention, there is no particular limitation for the first MVR vaporising devices 2, 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, MVR-FC continuous crystallisations It is one or more in evaporator, MVR-OSLO continuous crystallisation evaporators.Wherein, preferably MVR forced-circulation evaporators, MVR- FC continuous crystallisation evaporators, more preferably falling liquid film+forced circulation two-stage MVR crystallizing evaporators.

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~ 110 DEG C, pressure is -37kPa~12kPa；It is particularly preferred that the condition of first evaporation includes：Temperature is 95 DEG C~105 DEG C, pressure is -37kPa~-7kPa.

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.

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 will before the pending waste water is carried out the first evaporation First steam containing ammonia carries out the first heat exchange with the pending waste water and obtains the first ammonium hydroxide.First heat exchange There is no particular limitation for mode, and the heat exchange mode that this field routine may be used carries out.The number of first heat exchange can be with More than primary, preferably 2-4 times, more preferably 2-3 times.After first heat exchange, the ammonium hydroxide of output is cooled, heat Amount utmostly recycles inside processing unit, and the energy is rationally 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, the 5th heat-exchanger rig 35 and the second heat-exchanger rig 32 carry out, and specifically, the first steam containing ammonia are passed sequentially through the Two heat-exchanger rigs 32 and the first heat-exchanger rig 31, by the second liquid of steam condensation containing ammonia by third heat-exchanger rig 33, by sulfur acid Second concentrate of sodium crystal and sodium chloride crystal passes through first by the 5th heat-exchanger rig 35, while by the pending waste water In heat-exchanger rig 31, third heat-exchanger rig 33 and the 5th heat-exchanger rig 35 after one or more again by the second heat-exchanger rig 32 with First steam containing ammonia carries out second of first heat exchange.By first heat exchange, the pending waste water heating is made to be convenient for It is evaporated, while first steam cooling containing ammonia being made to obtain the first ammonium hydroxide, first ammonium hydroxide can be stored in the first ammonia In water storage tank 51；The second steam condensation containing ammonia liquid is set to cool down to obtain the second ammonium hydroxide simultaneously, second ammonium hydroxide can be stored In the second tank used for storing ammonia 52；The second concentrate cooling is set to be convenient for low-temperature treatment simultaneously；Second concentrate can To carry out low-temperature treatment in low-temperature treatment tank 55.

In the present invention, for first heat-exchanger rig 31, third heat-exchanger rig 33, the 5th heat-exchanger rig 35 and second There is no particular limitation for heat-exchanger rig 32, can use various heat exchangers commonly used in the art, reaches described first and contains ammonia Steam carries out the purpose of first heat exchange with the pending waste water.Specifically, it can be jacketed type exchanger, plate Formula heat exchanger, shell-and-tube heat exchanger etc., wherein preferably plate heat exchanger.The material of the heat exchanger can be specific as needed Selection can select material to be changed for two phase stainless steel, titanium or titanium alloy, Hastelloy such as in order to resist chloride ion corrosion Hot device can select the heat exchanger containing plastic material when temperature is relatively low.

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 74 DEG C~174 DEG C, Further preferably 79 DEG C~129 DEG C, be still more preferably 94 DEG C~104 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.

Preferably pass through second heat-exchanger rig 32 according to the present invention in order to make full use of the thermal energy of the first steam containing ammonia After carrying out the first heat exchange, the temperature of the pending waste water is 50 DEG C~370 DEG C, more preferably 72 DEG C~182 DEG C, further Preferably 85 DEG C~137 DEG C, be still more preferably 102 DEG C~112 DEG C.

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 in the first MVR vaporising devices 2 into The pending waste water is being sent into the first heat-exchanger rig 31, third heat-exchanger rig 33 or the progress of the 5th heat-exchanger rig 35 the by row Before one heat exchange, by by the pending waste water be sent into the pipeline of above-mentioned heat-exchanger rig import described in contain basic species The aqueous solution of matter and mixing, to carry out first time pH value adjusting；Then the pending waste water be sent into the second heat-exchanger rig 32 into The first heat exchange of row, and contain basic species the pending waste water to be sent into the pipeline of the second heat-exchanger rig 32 described in importing The aqueous solution of matter and mixing, to carry out second of pH value adjusting.It is adjusted by pH value twice, the pending waste water is made to be passed through PH value before first MVR vaporising devices 2 is more than 9, preferably greater than 10.8.Preferably, first time pH value, which is adjusted, makes The pH value of pending waste water is more than 7 (preferably 7-9), and second of pH value is adjusted so that pH value is more than 9 (being preferably greater than 10.8). In accordance with the present invention it is preferred that before carrying out first heat exchange, 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 pipeline of the first heat-exchanger rig 31, third heat-exchanger rig 33 and the 5th heat-exchanger rig 35, is arranged the measurement of the first pH value Device 61 measures the pH value after first time pH value is adjusted, in the pipeline that the pending waste water is sent into the second heat-exchanger rig 32 It is upper that second pH value measuring device 62 is set to measure the pH value after second of pH value is adjusted.

In the present invention, in order to improve the solid content in the first MVR vaporising devices 2, the ammonia reduced in liquid contains Amount, preferably by the partially liq after the first MVR vaporising devices 2 evaporation (namely inside the first MVR vaporising devices Liquid, also referred to as first circulation liquid hereinafter) again return in the first MVR vaporising devices 2 and evaporate.It is above-mentioned by described first The process of circulation fluid back to the first MVR vaporising devices 2 is preferably to adjust it by first circulation liquid and in first time pH value It again returns in the first MVR vaporising devices 2 afterwards and after the pending waste water mixing before being adjusted to second of pH value, for example, 72 can be pumped by second circulation to return to the first circulation liquid between the first heat-exchanger rig 31 and the second heat-exchanger rig 32 Waste water conveyance conduit in mixed with pending waste water, then adjusting by second of pH value and then changing second Thermal 32 carries out heat exchange, is finally sent into the first MVR vaporising devices 2.It is evaporated as the first MVR vaporising devices 2 will be passed through The ratio that partially liq afterwards flows back into the first MVR vaporising devices 2 is not particularly limited, and ensures that the first MVR vaporising devices 2 exist The water and ammonia of requirement can be evaporated under given evaporating temperature, such as can be 10-200, preferably 40- 100.Here, the first reflux ratio refers to：Regurgitant volume subtracts regurgitant volume with the total amount of liquid being sent into the first MVR vaporising devices 2 Ratio.

In the case of, according to the invention it is preferred to, the method further include after first steam containing ammonia is compressed again Carry out first heat exchange.The compression of first steam containing ammonia can be carried out by the first compressor 101.By to described First steam containing ammonia is compressed, and to input energy in MVR vapo(u)rization systems, ensures that the process of waste water heating-evaporation-cooling is continuous It carries out, needs to input when MVR evaporation processes start and start steam, reach after continuously running state only by the first compressor 101 Energy supply, it is no longer necessary to input other energy.Various compressions commonly used in the art may be used in first compressor 101 Machine, such as centrifugal blower, turbocompressor or lobed rotor compressor etc..After the compression of the first compressor 101, the first steam containing ammonia Temperature increase 5 DEG C~20 DEG C.

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 the 2nd 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, it is The impurity of removal absorption, reduces the peculiar smell of solid salt, reduces corrosivity, improves the purity of the crystal, it is preferable that the sulphur Sour sodium crystal water, the catalyst production waste water or metabisulfite solution carry out the first washing and drying.In order to avoid washed The dissolving of sodium sulfate crystal in journey, it is preferable that the sodium sulfate crystal is washed with aqueous sodium persulfate solution.It is highly preferred that institute It states sodium chloride and sodium sulphate at the concentration preferably temperature corresponding to sodium sulfate crystal to be washed of aqueous sodium persulfate solution while reaching The concentration of sodium sulphate in the aqueous solution of saturation.

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 completion of the first heat exchange before the first evaporation, such as passes through the 8th circulating pump 78 and return to second After heat-exchanger rig 32 carries out heat exchange, it is re-fed into the first MVR vaporising devices 2.

A preferred embodiment according to the present invention contains sulfuric acid by what the evaporation of the first MVR vaporising devices 2 obtained First concentrate of sodium is carried out with the catalyst production waste water in eluriating tank after settling progress tentatively separation of solid and liquid It eluriates for the first time, then reuses the liquid obtained when subsequent wash sodium sulfate crystal and carried out second in another elutriation tank It eluriates, finally will be sent into equipment for separating liquid from solid by the slurries eluriated twice is separated by solid-liquid separation, the crystal being separated by solid-liquid separation During the liquid for being eluted again with aqueous sodium persulfate solution, and elution being obtained is eluriated back to second.By above-mentioned washed Journey, the purity of the sodium sulfate crystal not only made improve, and will not be excessive introducing cleaning solution, improve the effect of wastewater treatment Rate.

In the present invention, there is no particular limitation for the 2nd 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, MVR-FC continuous crystallisations It is one or more in evaporator, MVR-OSLO continuous crystallisation evaporators.Wherein, preferably MVR forced-circulation evaporators, MVR- FC continuous crystallisation evaporators, more preferably falling liquid film+forced circulation two-stage MVR crystallizing evaporators.

In the present invention, the evaporation conditions of second evaporation can be selected suitably as needed, and institute can be controlled by reaching The evaporation capacity for stating the second evaporation, make sodium sulphate, sodium chloride at the same crystallize precipitation (i.e. second evaporation obtain sulfur acid sodium crystal and chlorine Change the second concentrate of sodium crystal), then make the second of sulfur acid sodium crystal and sodium chloride crystal to concentrate by the low-temperature treatment Sodium sulfate crystal dissolving in liquid, sodium chloride further crystallize precipitation, obtain the purpose for the treatment fluid for containing only sodium chloride crystal i.e. It can.It is described second evaporation condition may include：Temperature is 35 DEG C or more, and pressure is -95kPa or more；In order to improve evaporation effect Rate, 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 is -87kPa~18110kPa；Preferably, the condition of second evaporation includes：Temperature is 75 DEG C~175 DEG C, pressure Power is -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 be 95 DEG C~110 DEG C, pressure be -37kPa~ 12kPa；It is particularly preferred that the condition of second evaporation includes：Temperature be 105 DEG C~110 DEG C, pressure be -8kPa~ 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 100L/h or more (such as 0.1m³/ h~500m³/h)。

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.

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 the treatment fluid The concentration of sodium sulphate when saturation.By by second evaporation extent control within the above range, it is ensured that the sodium sulphate of precipitation It can all be dissolved under the conditions of low-temperature treatment, while sodium chloride crystallization as much as possible being made to be precipitated.By being steamed as possible second Make sodium chloride polycrystalline in hair, 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.

A preferred embodiment according to the present invention, second evaporation process in the 2nd MVR vaporising devices 1 into First mother liquor is passed through in the 2nd MVR vaporising devices 1 by the 6th circulating pump 76 and carries out the second evaporation and obtain the by row Second concentrate of two steam containing ammonia and sulfur acid sodium crystal and sodium chloride crystal.

According to the present invention, second steam containing ammonia is separated by solid-liquid separation obtained liquid phase with described first and carries out the second heat friendship It changes and obtains the second ammonium hydroxide.Preferably, the second steam containing ammonia that the 2nd MVR vaporising devices evaporate is successively with described One is separated by solid-liquid separation obtained liquid phase, the pending waste water carries out the second heat exchange and obtains the second ammonium hydroxide.Second heat is handed over There is no particular limitation for the mode changed, and the heat exchange mode that this field routine may be used carries out.The number of the heat exchange can be with More than primary, preferably 2-4 times, more preferably 2-3 times, particularly preferably 2 times.Pass through the heat exchange, the ammonium hydroxide of output Cooled, heat utmostly recycles inside processing unit, and the energy is rationally utilized, and reduces waste.

In the case of, according to the invention it is preferred to, second heat exchange is carried out by the 4th heat-exchanger rig 34, specifically, By the second steam containing ammonia by the 4th heat-exchanger rig 34, and the mixed liquor of first mother liquor and second circulation liquid is passed through the 4th Heat-exchanger rig 34 carries out second heat exchange, and the second steam containing ammonia is made to condense, and makes first mother liquor and second circulation liquid Mixed liquor heating is convenient for evaporating, while second steam containing ammonia being made to condense to obtain the second ammonium hydroxide, and second ammonium hydroxide can Further to carry out the first heat exchange in third heat-exchanger rig 33, finally it is stored in the second tank used for storing ammonia 52.

According to the present invention, after the second heat exchange, the temperature of the mixed liquor of first mother liquor and second circulation liquid is 35 DEG C or more, more preferably 50 DEG C~200 DEG C, further preferably 75 DEG C~184 DEG C, be still more preferably 85 DEG C~139 ℃。

In the present invention, in order to improve the solid content in the 2nd MVR vaporising devices 1, the ammonia reduced in liquid contains Amount, preferably by the partially liq after the 2nd MVR vaporising devices 1 evaporation (namely in the 2nd MVR vaporising devices 1 The liquid in portion, also referred to as second circulation liquid) it flows back into the 2nd MVR vaporising devices 1.It is above-mentioned to return the second circulation liquid The process for flowing to the 2nd MVR vaporising devices 1 is preferably, by second circulation liquid and the first mother liquor, the second optional cleaning solution Mixing, then carry out the second heat exchange with the second steam containing ammonia.For example, by second circulation liquid and can be appointed by the 7th circulating pump 77 Second cleaning solution of choosing is passed through the second heat exchange of progress of the 4th heat-exchanger rig 34 again after being mixed in the duct with the first mother liquor after, return Return the 2nd MVR vaporising devices 1.It is steamed as the partially liq after the evaporation of the 2nd MVR vaporising devices 1 is flowed back into the 2nd MVR The ratio of transmitting apparatus 1 is not particularly limited, and ensures that the 2nd MVR vaporising devices 1 can evaporate under given evaporating temperature Go out the water and ammonia of requirement, such as can be 0.1-100, preferably 5-50.Here, the second reflux ratio refers to：Reflux Amount subtracts the ratio of regurgitant volume with the total amount of liquid being sent into the 2nd 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 the second compressor 102.By to described Second steam containing ammonia is compressed, and to input energy in MVR vapo(u)rization systems, ensures that the process of waste water heating-evaporation-cooling is continuous It carries out, needs to input when MVR evaporation processes start and start steam, reach after continuously running state only by the second compressor 102 Energy supply, it is no longer necessary to input other energy.Various compressions commonly used in the art may be used in second compressor 102 Machine, such as centrifugal blower, turbocompressor or lobed rotor compressor etc..After second compressor 102 compression, described second The temperature of the steam containing ammonia increases 5 DEG C~20 DEG C.

In the present invention, the second concentrate of the sulfur acid sodium crystal and sodium chloride crystal is subjected to low-temperature treatment, made Sodium sulfate crystal dissolves, and obtains the treatment fluid of sodium chloride-containing crystal.By controlling the evaporation capacity of second evaporation, make the place A concentration of Y of sodium sulphate in liquid is managed hereinafter, can make in low-temperature process, sodium sulfate crystal can be completely dissolved (wherein, Y For under conditions of low-temperature treatment, the concentration of sodium sulphate when sodium sulphate and sodium chloride reach saturation in treatment fluid).

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 17.9 DEG C~25 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, more preferably 55min~65min.

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：5 DEG C higher than the temperature of low-temperature treatment of the temperature or more of first evaporation, preferably high 20 DEG C or more, more preferably 35 DEG C high~ It is 90 DEG C, further preferably 35 DEG C high~70 DEG C, it is particularly preferably 50 DEG C high~60 DEG C.Pass through the first evaporation of control and low-temperature treatment Temperature makes sodium sulphate in the first evaporation individually crystallize precipitation, makes the second evaporation is precipitated in low-temperature treatment sodium sulfate crystal and chlorine The sodium sulphate changed in sodium crystal can dissolve, to improve the purity of obtained sodium sulphate and sodium chloride crystal.

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 the first MVR vaporising devices 2 can be returned and carry out the first evaporation again, can specifically pass through Second mother liquor is returned before first time pH value is adjusted or is given birth to before second of pH value adjusting with catalyst by the 9th circulating pump 79 Production waste water is mixed to get pending waste water.In addition, be difficult to avoid that on obtained sodium chloride crystal can adsorb certain sulfate radical from The impurity such as son, free ammonia, hydroxide ion reduce the peculiar smell of solid salt to remove the impurity of absorption, reduce corrosivity, carry The purity of the high crystal, it is preferable that sodium chloride crystal water, the catalyst production waste water or sodium chloride solution carry out Second washing is simultaneously dry.In order to avoid the dissolving of sodium chloride crystal in washing process, it is preferable that the sodium chloride crystal chlorination Sodium water solution is washed.It is highly preferred that the concentration of the sodium-chloride water solution is preferably corresponding to sodium chloride crystal to be washed At a temperature of sodium chloride and sodium sulphate reach the concentration of sodium chloride in the aqueous solution of saturation simultaneously.

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 that liquid is back to before the evaporation of the first MVR vaporising devices Before value is adjusted, water or sodium-chloride water solution leacheate and elutriation liquid are back to the 2nd MVR vaporising devices, such as are followed by the tenth 80 the 2nd MVR vaporising devices 1 of return of ring pump carry 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 (concentration of the sodium-chloride water solution is preferably sodium chloride and sodium sulphate at the temperature corresponding to sodium chloride crystal to be washed to aqueous solution Reach the concentration of sodium chloride in the aqueous solution of saturation simultaneously) it is eluted, and washed in a pan obtained liquid is eluted back to second It washes middle as elutriation liquid.The washing process combined by above-mentioned elutriation and elution, the purity of the sodium chloride crystal not only made Improve, and will not be excessive introducing cleaning solution, improve 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 remaining tail gas by second heat exchange to pass through Except being discharged after ammonia.First steam containing ammonia condenses remaining tail gas, that is, second heat-exchanger rig by first heat exchange The tail gas of 32 discharges, second steam containing ammonia condense remaining i.e. the 4th heat-exchanger rig 34 of tail gas by second heat exchange The tail gas of discharge.By the way that above-mentioned tail gas is removed ammonia, the pollutant load in emission can be further decreased so that it can straight Run in and puts.

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 100g/L hereinafter, preferably 50g/L or less.

It is useless relative to catalyst production from the point of view of the energy consumption for reducing processing procedure from the efficiency for improving the first evaporation The SO contained in water₄ ^2-, the Cl in catalyst production waste water^-The lower content the better, for example, relative to 1 mole of catalyst life The SO contained in production waste water₄ ^2-, the Cl that contains in the catalyst production waste water^-For 30 moles hereinafter, preferably 20 moles with Under, more preferably 15 moles hereinafter, further preferably 10 moles or less.And from the point of view of practicability, relative to 1 mole The SO contained in the catalyst production waste water₄ ^2-, the Cl that contains in the catalyst production waste water^-Preferably 0.1 mole with On, more preferably 0.5 mole or more, further preferably 1 mole or more, such as 1-5 moles.By the way that the catalyst is produced The SO contained in waste water₄ ^2-And Cl^-Molar ratio be limited to above range, most of water can be steamed in the first evaporation, be subtracted The circulation fluid scale of construction in few system for handling, 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, 6.2~6.6.

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 (80g/L containing NaCl, Na₂SO₄ 81g/L、NH₄Cl48g/L、(NH₄)₂SO₄49.4g/L, pH 6.2) with inlet amount it is 5m³The speed of/h is mixed to get pending waste water with the second mother liquor and (wherein contains Some SO₄ ^2-And Cl^-Molar ratio be 1：3.7487) after, the first heat-exchanger rig 31, third heat-exchanger rig 33 and are being sent to By the first pH value measuring device 61 (pH meter) to mixed in the main pipeline of five heat-exchanger rigs 35 (being titanium alloy plate heat exchanger) PH value after conjunction is monitored (measured value 9.2), and 71 are pumped by a part (3m of pending waste water by first circulation³/ h) it send Entering the first heat-exchanger rig 31 and the first steam condensation containing ammonia liquid and carrying out the first heat exchange makes pending waste water be warming up to 99 DEG C, another Partly (2m³/ h) it is sent into the first heat exchange of progress of third heat-exchanger rig 33 and the second steam condensation containing ammonia liquid and makes pending waste water liter To 99 DEG C, rest part is sent into the second concentrate the first heat exchange of progress that the 5th heat-exchanger rig 35 is obtained with the second evaporation to be made temperature Pending waste water is warming up to 102 DEG C, then converges pending waste water and is sent into the second heat-exchanger rig 32；By pending waste water It is sent into the main pipeline of the second heat-exchanger rig 32 and imports second of pH of sodium hydrate aqueous solution progress of a concentration of 45.16 mass % Value is adjusted, and is monitored (measured value 10.8) to the pH value after adjusting by the second pH value measuring device 62 (pH meter), so Being sent into the first steam containing ammonia the first heat exchange of progress of the second heat-exchanger rig 32 (titanium alloy plate heat exchanger) and recycling afterwards makes to wait for Processing waste water is warming up to 107 DEG C, then pending waste water is being sent into 2 (falling liquid film+forced circulation two-stage MVR of the first MVR vaporising devices Crystallizing evaporator) it is evaporated, obtain the first concentrate of the first steam containing ammonia and sulfur acid sodium crystal.Wherein, the first MVR steams The evaporating temperature of transmitting apparatus 2 is 100 DEG C, and pressure is -22.82kPa, evaporation capacity 3.82m³/h.It evaporates first obtained and contains ammonia Steam (12 DEG C of temperature rise) after the compression of the first compressor 101 passes sequentially through the second heat-exchanger rig 32 and the first heat-exchanger rig 31 carry out heat exchange with pending waste water, and condensation obtains the first ammonium hydroxide, and is stored in the first tank used for storing ammonia 51.In addition, in order to The solid content in the first MVR vaporising devices 2 is improved, using the partially liq after being evaporated in the first MVR vaporising devices 2 as first Circulation fluid by second circulation pump 72 be recycled to the second heat-exchanger rig 32 heat exchange, be then again introduced into the first MVR vaporising devices 2 into Row first evaporates (reflux ratio 75.9).The degree evaporated by the densitometer pair first that is arranged on the first MVR vaporising devices 2 into Row monitoring, controls a concentration of 0.9935X (306.2g/L) of the first evaporation concentrated solution sodium chloride.

Above-mentioned first concentrate is sent into the first equipment for separating liquid from solid 91 (centrifuge) and carries out the first separation of solid and liquid, per hour Obtain 4.48m³Contain NaCl 306.2g/L, Na₂SO₄ 54.0g/L、NaOH 1.3.8g/L、NH₃The first of 0.60g/L is female Liquid is temporarily stored into the first mother liquor tank 53, is separated by solid-liquid separation gained solid sodium sulfate and (is obtained the sodium sulphate of aqueous 15 mass % per hour Crystalli-zation cake 664.41kg, the wherein content of sodium chloride be 5.0 mass % or less) with sulfate crystal filter cake butt quality phase Deng 54g/L metabisulfite solution elution, sodium sulphate 664.41kg (purity is 99.4 weight %) is obtained after dry per hour, is washed It washs liquid and is recycled to before second pH is adjusted by the 8th circulating pump 78 and mixed with pending waste water, be then again introduced into first MVR vaporising devices 2 carry out the first evaporation.

Second evaporation process is in the 2nd MVR vaporising devices 1 (falling liquid film+forced circulation two-stage MVR crystallizing evaporators) It carries out.The first mother liquor in above-mentioned first mother liquor tank 53 is sent into the 2nd 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.Wherein, the 2nd MVR steams The evaporating temperature of transmitting apparatus 1 is 105 DEG C, and pressure is -7.02kPa, evaporation capacity 2.01m³/h.In order to improve the 2nd MVR evaporations Solid content in device 1, using the first mother liquor of part after being evaporated in the 2nd MVR vaporising devices 1 as second circulation liquid by the Seven circulating pumps 77 are recycled to the heat exchange of the 4th heat-exchanger rig 34, are then again introduced into the 2nd MVR vaporising devices 1 and carry out the second evaporation (reflux ratio 42.3).Evaporate obtained the second steam containing ammonia after the second compressor 102 compresses (12 DEG C of temperature rise) according to It is secondary by the 4th heat-exchanger rig 34 and third heat-exchanger rig 33, respectively with the first mother liquor, first circulation pump 71 conveying part wait for It handles waste water and carries out heat exchange, cooling obtains the second ammonium hydroxide, and is stored in the second tank used for storing ammonia 52.It is evaporated by the 2nd MVR The degree that the mass flowmenter pair second being arranged on device 1 evaporates is monitored, and the evaporation capacity of the second evaporation of control is 2.01m³/ H (is equivalent to a concentration of 0.979Y of sodium sulphate in control process liquid, i.e. 91.6g/L).First mother liquor is in the 2nd MVR vaporising devices After being evaporated in 1, the second concentrate of obtained sulfur acid sodium crystal and sodium chloride crystal carries out low temperature in low-temperature treatment tank 55 Processing, temperature are 17.9 DEG C, and residence time 70min obtains the treatment fluid of sodium chloride-containing crystal.

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, 2.58m is obtained per hour³Contain NaCl 277.6g/L, Na₂SO₄ 91.6g/L、NaOH 2.34g/L、NH₃The of 0.01g/L Two mother liquors, the second mother liquor are temporarily stored into the second mother liquor tank 54.Second mother liquor is all recycled to by the 9th circulating pump 79 useless Water import pipe is mixed to get pending waste water with waste water, and being separated by solid-liquid separation gained solid sodium chloride, (obtaining water content per hour is The sodium chloride crystalli-zation cake 769.43kg of 14 mass %, the wherein content of sodium sulphate are 6.0 mass % or less) it is done with sodium chloride After the equal 277.6g/L sodium chloride solutions elution of matrix amount, partial oxidation sodium crystalli-zation cake is for preparing 277.6g/L sodium chloride Solution, it is dry in drying machine, sodium chloride 661.71kg (purity is 99.5 weight %) is obtained per hour, and cleaning solution passes through the tenth After circulating pump 80 is back to the heat exchange of the 4th heat-exchanger rig 34, it is back to the 2nd 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 3.83m of a concentration of 3.45 mass % is obtained in the first tank used for storing ammonia 51 per hour³, The ammonium hydroxide 2.01m of a concentration of 0.137 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 NaCl65g/L, Na₂SO₄ 130g/L、NH₄Cl 12g/L、(NH₄)₂SO₄The catalyst production waste water that 24.4g/L, pH are 6.5 is handled, and is obtained To pending waste water in the SO that contains₄ ^2-And Cl^-Molar ratio be 1：2.291.By a part (4m of pending waste water³/ h) it is logical The first heat-exchanger rig 31 is crossed, carrying out the first heat exchange with the first liquid of steam condensation containing ammonia of recycling makes pending waste water be warming up to 94 DEG C, another part (1m³/ h) by third heat-exchanger rig 33, carry out the first heat exchange with the second liquid of steam condensation containing ammonia of recycling Pending waste water is set to be warming up to 99 DEG C, rest part carries out the first heat exchange by the 5th heat-exchanger rig 35, with the second concentrate So that pending waste water is warming up to 99 DEG C, is by the temperature of pending waste water after the progress heat exchange of the second heat-exchanger rig 32 after converging 107℃.The evaporating temperature of first MVR vaporising devices 2 is 95 DEG C, and pressure is -36.36kPa, evaporation capacity 4.31m³/h.Second The evaporating temperature of MVR vaporising devices 1 is 100 DEG C, and pressure is -22.83kPa, evaporation capacity 1.17m³/h.The temperature of low-temperature treatment It is 20 DEG C, residence time 55min.

First equipment for separating liquid from solid 91 obtains 911.15kg tons of the sulfate crystal filter cake of aqueous 14 mass % per hour, most Obtain sodium sulphate 783.59kg per hour eventually (purity is 99.5 weight %)；2.68m is obtained per hour³A concentration of NaCl 307.2g/L、Na₂SO₄ 54.5g/L、NaOH 1.83g/L、NH₃The first mother liquor of 0.35g/L.

Second equipment for separating liquid from solid 92 obtains the sodium chloride crystalli-zation cake 456.76kg that water content is 15 mass % per hour, It is final to obtain sodium chloride 38.24kg per hour (purity is 99.6 weight %)；1.67m is obtained per hour³A concentration of NaCl 279.5g/L、Na₂SO₄ 88.7g/L、NaOH 4.13g/L、NH₃The second mother liquor of 0.011g/L.

In the present embodiment, the ammonium hydroxide 4.31m of a concentration of 1.1 mass % is obtained in the first tank used for storing ammonia 51 per hour³, the The ammonium hydroxide 1.17m of a concentration of 0.085 mass % is obtained in two tank used for storing ammonia 52 per hour³, ammonium hydroxide can be back to the life of 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 NaCl168g/L, Na₂SO₄ 35g/L、NH₄Cl 40g/L、(NH₄)₂SO₄The catalyst production waste water that 8.47g/L, pH are 6.6 is handled, and is obtained Pending waste water in the SO that contains₄ ^2-And Cl^-Molar ratio be 1：9.3964.Heat exchange is carried out by the first heat-exchanger rig 31 The temperature of pending waste water is 99 DEG C afterwards, and the temperature by pending waste water after the progress heat exchange of third heat-exchanger rig 33 is 99 DEG C, by the 5th heat-exchanger rig 35 carry out heat exchange after pending waste water temperature be 105 DEG C, by the second heat-exchanger rig 32 into The temperature of pending waste water is 112 DEG C after row heat exchange.The evaporating temperature of first MVR vaporising devices 2 be 105 DEG C, pressure be- 7.02kPa, evaporation capacity 2.36m³/h.The evaporating temperature of 2nd MVR vaporising devices 1 is 110 DEG C, pressure 11.34kPa, is steamed Hair amount is 3.16m³/h.25 DEG C of the temperature of low-temperature treatment, residence time 50min.

First equipment for separating liquid from solid 91 obtains the sulfate crystal filter cake 251.35kg of aqueous 14 mass % per hour, finally Obtain sodium sulphate 216.16kg per hour (purity is 99.6 weight %)；8.22m is obtained per hour³A concentration of NaCl 306.4g/ L、Na₂SO₄ 52.5g/L、NaOH 2.64g/L、NH₃The first mother liquor of 0.18g/L.

Second equipment for separating liquid from solid 92 obtains the sodium chloride crystalli-zation cake that water content is 14 mass % per hour 1236.21kg finally obtains sodium chloride 1063.14kg per hour (purity is 99.5 weight %)；5.03m is obtained per hour³It is dense Degree is NaCl 279.5g/L, Na₂SO₄ 82.2g/L、NaOH 4.13g/L、NH₃The second mother liquor of 0.017g/L.

In the present embodiment, the ammonium hydroxide 2.36m of a concentration of 3.0 mass % is obtained in the first tank used for storing ammonia 51 per hour³, the The ammonium hydroxide 3.16m of a concentration of 0.044 mass % is obtained in two tank used for storing ammonia 52 per hour³, ammonium hydroxide can be back to the life of 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 the first evaporation of the first MVR vaporising devices progress and obtains the first steam containing ammonia and sulfur acid sodium crystalline substance First concentrate of body, 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 in the 2nd MVR vaporising devices and carries out the second evaporation, obtain the second steam containing ammonia and sulfur acid sodium crystal and sodium chloride Second concentrate of crystal；

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 the first MVR vaporising devices, the pH value for adjusting the pending waste water is big In 9；

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 the first MVR vaporising devices, the pH value of the pending waste water is adjusted More than 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 the 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.

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~110 DEG C, and pressure is -37kPa~12kPa.

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 first MVR vaporising devices, First steam containing ammonia is subjected to the first heat exchange with the pending waste water and obtains the first ammonium hydroxide；

Preferably, before carrying out first heat exchange, the pH value for adjusting the 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 that the 2nd MVR vaporising devices evaporate Obtained liquid phase is separated by solid-liquid separation with described first to carry out the second heat exchange and obtain the second ammonium hydroxide；

Preferably, the 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.