CN103508602A - Membrane and evaporative crystallization integrated high-salinity industrial wastewater zero-discharge process - Google Patents

Abstract

Translated fromChinese

本发明涉及一种膜与蒸发结晶集成的高盐度工业废水零排放的工艺，将工业废水经超滤预处理后经过高压泵输送至反渗透过程，渗透侧出水回用，对过滤多次后的浓缩液进行电渗析处理，经电渗析浓缩后的物料进行蒸发和结晶，得到盐泥和冷凝水，对盐泥进行后处理，冷凝水回用。本发明将膜与蒸发结晶耦合不仅能从高盐浓度的工业废水中回收高质量的净水，也能实现高盐废水的零排放，具有能耗低，生产成本低，工艺先进的特点。The invention relates to a zero-discharge process of high-salinity industrial wastewater integrated with membrane and evaporation crystallization. The industrial wastewater is pretreated by ultrafiltration and then transported to the reverse osmosis process through a high-pressure pump, and the effluent from the permeation side is reused. The concentrated solution is subjected to electrodialysis treatment, and the material concentrated by electrodialysis is evaporated and crystallized to obtain salt mud and condensed water. The salt mud is post-treated and the condensed water is reused. The invention couples the membrane with evaporation and crystallization, not only can recover high-quality clean water from high-salt industrial wastewater, but also can realize zero discharge of high-salt wastewater, and has the characteristics of low energy consumption, low production cost and advanced technology.

Description

The technique of the high salinity zero discharge of industrial waste water that a kind of film and evaporative crystallization are integrated

Technical field

The present invention relates to a kind of sewage water treatment method, relate in particular to the technique of the integrated high salinity zero discharge of industrial waste water of a kind of film and evaporative crystallization, the trade effluent that adopts membrane technique and evaporative crystallization integrated technique to produce chemical fields such as chlor-alkali, papermaking is processed, from the trade effluent of high TDS, reclaim high-quality water purification, realize the zero release of high-salt wastewater.

Background technology

At present, the treatment process of the trade effluent that the chemical fields such as chlor-alkali, papermaking, plating produce mainly comprises chemical precipitation method, oxidation reduction process, membrane separation process and ion exchange method, but these traditional technologys are difficult to reach the requirement of zero release.

So-called zero release, with regard to its content, wants to have no alternative but in production control process the waste discharge of generation on the one hand, is reduced to zero; On the other hand the waste of haveing no alternative but discharge is made full use of, finally stop the generation of Nonrenewable resources and the energy.Zero-discharge technology is integrated application membrane sepn, evaporative crystallization and/or physics, chemistry, the biological process such as dry, solid impurity in the middle of waste water is concentrated into very high density, most of water has returned to cyclically utilizing, the remaining water of following on a small quantity solid waste, can pass through the approach such as evaporation/crystallization, evaporation/dry, solid waste absorption and process recycling, and not discharge system.

Summary of the invention

The object of the invention is the deficiency for above-mentioned method of wastewater treatment, the present invention proposes the technique of the integrated high salinity zero discharge of industrial waste water of a kind of film and evaporative crystallization, realize the zero release of high-quality water purification recovery and high-salt wastewater.

Technical scheme of the present invention is: the technique of the high salinity zero discharge of industrial waste water that a kind of film and evaporative crystallization are integrated, and its concrete steps are as follows:

1) high salinity trade effluent is carried out to ultrafiltration pretreatment, filter the insoluble solid impurities of removing in water, obtain penetrating fluid and trapped fluid;

2) adopt high-pressure pump that the penetrating fluid after ultrafiltration pretreatment is delivered to reverse osmosis membrane filtration device and carry out concentration; The water purification reuse of per-meate side;

3) when reverse osmosis membrane concentrated solution total dissolved solidss TDS reaches 27000～72000mg/L, concentrated material in reverse osmosis unit is delivered to electrodialysis unit and carries out concentration, be concentrated into TDS in material and reach 100000～172000mg/L, per-meate side water outlet is delivered to waterworks reuse;

4) concentrated solution after electrodialysis process is carried out to evaporation process, the distilled water obtaining is transported to waterworks reuse, and the salt slurry in the aqua storage tank of evaporator tower bottom is discharged by water circulating pump, and salt slurry is carried out to aftertreatment.

The TDS of above-mentioned high salinity trade effluent is 1500～4000mg/L, and solid suspension substrate concentration SS is 5～50mg/L, COD_crbe 20～100mg/L; After uf processing, the TDS of penetrating fluid is 1500～4000mg/L, and SS is 0～10mg/L, COD_crbe 15～90mg/L.

Preferably ultrafiltration pretreatment process employing pressure actuated device is recycle pump, and working pressure is 0.05～0.5MPa; Ultra-filtration membrane is organic membrane or mineral membrane, and film mean pore size is 10～100nm; Membrane module is tubular membrane, rolled film or hollow-fibre membrane.

Preferred reverse osmosis concentrated liquid COD_crbe 500～1000mg/L; It is 50～450mg/L that reverse osmosis goes out water purification TDS, COD_crat 0～50mg/L; Reverse osmosis membrane material is polymeric amide, cellulose acetate or both form by polymeric amide, cellulose acetate composite membrane; The pressure actuated device of osmosis filtration process is recycle pump, and pressure actuated device is forced into 0.5～4MPa to material to be filtered.

The preferred dense water COD of electrodialysis_crat 100～1500mg/L; The TDS of electric osmose division water is 1000～4000mg/L, COD_crat 50～600mg/L.

Preferably described electrodialysis system adopts pole-reversing electroosmosis, packed-bed electrodialysis, electrodeless water power dialysis or bipolar membrane electrodialysis technique.

Preferably evaporative process adopts falling film evaporator or/and scraper evaporator; Evaporative process is 1～8 effect evaporation, and steam condition is 120～180 ℃, and pressure is 0.2～0.4MPa.General volume cycles of concentration is 10～30 times.

Beneficial effect:

The present invention is delivered to membrane filtration system through high-pressure pump by trade effluent and carries out RO process after ultrafiltration pretreatment, the purified water reuse of per-meate side, concentrated solution after filtering is repeatedly carried out to electrodialysis process, material after concentrated is evaporated, obtain salt slurry and water of condensation, salt slurry is carried out to aftertreatment, recycling condensing water.The present invention can not only reclaim high-quality water purification by film and evaporation coupling from the trade effluent of high TDS, also can realize the zero release of high-salt wastewater, has energy consumption low, and production cost is low, technique advanced person's feature.

Accompanying drawing explanation

Fig. 1 is the integrated high salinity zero discharge of industrial waste water process flow sheet of film and evaporative crystallization.

Embodiment

Embodiment 1

To TDS, be that 1500mg/L, SS are 5mg/L, COD_crfor the trade effluent of 35mg/L carries out ultrafiltration pretreatment, under the condition that adopts tubular fibre organic membrane that membrane pore size is 10nm to be 0.5MPa at transmembrane pressure, filter, producing water TDS is 1500mg/L, the about 1mg/L of SS, COD_crfor 18mg/L; Penetrating fluid after ultrafiltration pretreatment is delivered to reverse osmosis membrane filtration device by high-pressure pump, adopts polyamide reverse osmose membrane to carry out concentration, the TDS of dense water reaches 27000mg/L, COD_crduring for 500mg/L, stop concentrating, wherein the TDS of per-meate side fresh water is 50mg/L, COD_crfor 5mg/L, this fresh water reuse; Penetrating fluid after reverse-osmosis treated is delivered to packed-bed electrodialysis device by high-pressure pump and carries out concentration, in dense water, TDS reaches 100000mg/L, COD_crwhile reaching 120mg/L, stop, dilute side water outlet TDS is 1000mg/L, COD_crfor 600mg/L, this fresh water is delivered to waterworks reuse.Concentrated solution after electrodialysis process is delivered to mono-effective falling film evaporator by recycle pump and carries out evaporation process, vapor temperature is 120 ℃, and pressure is 0.22MPa.The salt slurry of evaporation and crystal process is discharged by water circulating pump, and salt slurry is carried out to aftertreatment.The distilled water that evaporative process obtains, is transported to waterworks reuse; Its process flow sheet as shown in Figure 1.

Embodiment 2

To TDS, be 4000mg/L, SS is 50mg/L, COD_crfor the trade effluent of 72mg/L carries out ultrafiltration pretreatment, under the condition that adopts tubular ceramic membrane that membrane pore size is 100nm to be 0.1MPa at transmembrane pressure, filter, producing water TDS is 4000mg/L, SS is 10mg/L, COD_crfor 45mg/L; Penetrating fluid after ultrafiltration pretreatment, by high-pressure pump, is delivered to reverse osmosis membrane filtration device, adopts cellulose acetate reverse osmosis film to carry out concentration, the TDS of dense water reaches 72000mg/L, COD_crwhile reaching 690mg/L, stop concentrating, the TDS that water is measured in infiltration is 420mg/L, COD_crfor 30mg/L, by per-meate side effluent reuse; Penetrating fluid after reverse-osmosis treated is delivered to bipolar membrane electrodialysis device by high-pressure pump and carries out concentration, in dense water, TDS reaches 172000mg/L, COD_crduring 780mg/L, stop concentrating, the TDS of dilute side water outlet is 4000mg/L, COD_crfor 80mg/L, this fresh water is delivered to waterworks reuse.Concentrated solution after electrodialysis process is delivered to eight effect falling film evaporators by recycle pump and carries out evaporation process, vapor temperature is 180 ℃, and pressure is 0.4MPa.Salt slurry is discharged by water circulating pump, and salt slurry is carried out to aftertreatment.The distilled water that evaporative process obtains, is transported to waterworks reuse.

Embodiment 3

To TDS, be 2000mg/L, SS is 30mg/L, COD_crfor the trade effluent of 86mg/L carries out ultrafiltration pretreatment, under the condition that adopts rolling organic membrane that membrane pore size is 50nm to be 0.2MPa at transmembrane pressure, filter, producing water TDS is 2000mg/L, SS is 4mg/L, COD_crfor 80mg/L; Penetrating fluid after ultrafiltration pretreatment, by high-pressure pump, is delivered to reverse osmosis membrane filtration device, adopts polymeric amide, cellulose acetate complex reverse osmosis membrane to carry out concentration, until the TDS of dense water reaches 36000mg/L, COD_crwhile reaching 950mg/L, by the water purification reuse of per-meate side, wherein the TDS of per-meate side water outlet is 235mg/L, COD_crfor 50mg/L; Dense water after reverse-osmosis treated is delivered to pole-reversing electroosmosis device by high-pressure pump and carries out concentration, be concentrated into TDS in dense water and reach 138000mg/L, COD_crduring for 1500mg/L, stop, dilute side water outlet TDS is 2800mg/L, COD_crfor 400mg/L, water outlet is delivered to waterworks reuse.Dense water after electrodialysis process is delivered to triple effect scraper-type vaporizer by recycle pump and carries out evaporation process, vapor temperature is 150 ℃, and pressure is 0.3MPa.Salt slurry is discharged by water circulating pump, and salt slurry is carried out to aftertreatment.The distilled water that evaporative process obtains, is transported to waterworks reuse.

Claims (7)

Translated fromChinese

1.一种膜与蒸发结晶集成的高盐度工业废水零排放的工艺，其具体步骤如下：1. A zero-discharge process of high-salinity industrial wastewater integrated with membrane and evaporation crystallization, the specific steps are as follows:1）对高盐度工业废水进行超滤预处理，过滤去除水中的不溶性固体杂质，得到渗透液和截留液；1) Perform ultrafiltration pretreatment on high-salinity industrial wastewater, filter and remove insoluble solid impurities in water, and obtain permeate and retentate;2）采用高压泵将经过超滤预处理后的渗透液输送至反渗透膜过滤装置进行浓缩处理；渗透侧的净水回用；2) Use a high-pressure pump to transport the permeate after ultrafiltration pretreatment to the reverse osmosis membrane filtration device for concentration treatment; the purified water on the permeate side is reused;3）当反渗透膜浓缩液总溶解固体TDS达到27000～72000mg/L时，将反渗透装置内的浓缩物料输送至电渗析装置进行浓缩处理，浓缩至物料中TDS达到100000～172000mg/L，渗透侧出水输送至供水系统回用；3) When the total dissolved solids TDS of the reverse osmosis membrane concentrate reaches 27,000-72,000 mg/L, the concentrated material in the reverse osmosis device is transported to the electrodialysis device for concentration treatment, and the TDS in the material reaches 100,000-172,000 mg/L. The side outlet water is sent to the water supply system for reuse;4）将经过电渗析处理后的浓缩液进行蒸发处理，得到的蒸馏水输送到供水系统回用，蒸发塔底部储水槽内的盐泥通过循环水泵排出，并对盐泥进行后处理。4) Evaporate the concentrated solution after the electrodialysis treatment, and transport the obtained distilled water to the water supply system for reuse. The salt mud in the water storage tank at the bottom of the evaporation tower is discharged through the circulating water pump, and the salt mud is post-treated.2.根据权利要求1所述一种膜与蒸发结晶集成的高盐度工业废水零排放的工艺，其特征在于高盐度工业废水的TDS为1500～4000mg/L，固体悬浮物浓度SS为5～50mg/L，COD_Cr为20～100mg/L；经超滤处理后渗透液的TDS为1500～4000mg/L，SS为0～10mg/L，COD_Cr为15～90mg/L。2. According to claim 1, a process for zero discharge of high-salinity industrial wastewater integrated with membrane and evaporation crystallization is characterized in that the TDS of high-salinity industrial wastewater is 1500-4000 mg/L, and the concentration of suspended solids (SS) is 5 ～50mg/L, COD_Cr is 20～100mg/L; TDS of permeate after ultrafiltration treatment is 1500～4000mg/L, SS is 0～10mg/L, COD_Cr is 15～90mg/L.3.根据权利要求1所述的工艺，其特征在于超滤预处理过程采用压力驱动装置为循环泵，操作压力为0.05～0.5MPa；超滤膜为有机膜或无机膜，膜平均孔径为10～100nm；膜组件为管式膜、卷式膜或中空纤维膜。3. The process according to claim 1, wherein the ultrafiltration pretreatment process adopts a pressure-driven device as a circulating pump, and the operating pressure is 0.05 to 0.5 MPa; the ultrafiltration membrane is an organic membrane or an inorganic membrane, and the average pore size of the membrane is 10 ~100nm; the membrane module is tubular membrane, roll membrane or hollow fiber membrane.4.根据权利要求1所述的工艺，其特征在于反渗透浓缩液COD_Cr为500～1000mg/L；反渗透所出净水TDS为50～450mg/L，COD_Cr在0～50mg/L；反渗透膜材料为聚酰胺、醋酸纤维素或由聚酰胺、醋酸纤维素两者构成的复合膜；反渗透过滤过程的压力驱动装置为循环泵，压力驱动装置对待过滤的物料加压至0.5～4MPa。4. The process according to claim 1, characterized in that the COD_Cr of the reverse osmosis concentrate is 500-1000 mg/L; the TDS of the purified water produced by the reverse osmosis is 50-450 mg/L, and the COD_Cr is 0-50 mg/L; The reverse osmosis membrane material is polyamide, cellulose acetate or a composite membrane composed of polyamide and cellulose acetate; the pressure driving device in the reverse osmosis filtration process is a circulating pump, and the pressure driving device pressurizes the material to be filtered to 0.5~ 4MPa.5.根据权利要求1所述的工艺，其特征在于电渗析浓水COD_cr在100～1500mg/L；电渗析产水的TDS为1000～4000mg/L，COD_Cr在50～600mg/L。5. The process according to claim 1, characterized in that the COD_{Cr of} electrodialysis concentrated water is 100-1500 mg/L; the TDS of electrodialysis water is 1000-4000 mg/L, and the COD_Cr is 50-600 mg/L.6.根据权利要求1所述的工艺，其特征在于所述的电渗析系统采用倒极电渗析、填充床电渗析、无极水电渗析或双极性膜电渗析工艺。6. The process according to claim 1, characterized in that the electrodialysis system adopts inverted electrode electrodialysis, packed bed electrodialysis, electrodeless hydrodialysis or bipolar membrane electrodialysis technology.7.根据权利要求1所述的工艺，其特征在于蒸发过程采用降膜式蒸发器或刮板蒸发器；蒸发过程为1～8效蒸发，蒸汽条件为120～180℃，压力为0.2～0.4MPa。7. The process according to claim 1, characterized in that the evaporation process adopts a falling film evaporator or a scraper evaporator; the evaporation process is 1-8 effect evaporation, the steam condition is 120-180 ° C, and the pressure is 0.2-0.4 MPa.

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