CN113461199A - Method and system for separating sodium carbonate and sodium bromide from PTA (pure terephthalic acid) oxidation tail gas washing tower discharge liquid - Google Patents
Method and system for separating sodium carbonate and sodium bromide from PTA (pure terephthalic acid) oxidation tail gas washing tower discharge liquid Download PDFInfo
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Abstract
The invention relates to a method for separating sodium carbonate and sodium bromide from the discharge liquid of a PTA oxidation tail gas washing tower, which comprises the following steps: adjusting the pH value of the washing tower effluent to 11.0-12.0 in a sodium bicarbonate removal tower by steam heating or adding sodium hydroxide to obtain decarbonized washing tower effluent; conveying the decarbonized washing tower discharge liquid to an ultrafiltration device to remove suspended particles to obtain ultrafiltration product water and ultrafiltration concentrated water, and discharging the ultrafiltration concentrated water; and conveying the ultrafiltration produced water to a two-stage nanofiltration device and a two-stage RO (reverse osmosis) device, wherein the I-stage nanofiltration concentrated water is a sodium carbonate-containing solution, and the I-stage RO concentrated water is a sodium bromide-rich solution. The invention relates to a separation system for sodium carbonate and sodium bromide in a discharge liquid of a PTA oxidation tail gas washing tower. The process and system of the present invention can convert sodium bicarbonate in the PTA oxidation tail gas scrubber effluent to sodium carbonate and separate it from sodium bromide.
Description
Technical Field
The invention belongs to the technical field of bromine-containing wastewater resource utilization, and particularly relates to an energy-saving decarbonization method and system for PTA oxidation tail gas washing tower discharge liquid.
Background
PTA (purified terephthalic acid) is one of the important bulk organic products downstream of petrochemical industry. At present, PTA is mainly produced by a paraxylene air oxidation method, and PTA oxidation tail gas generated in the production process is organic waste gas containing various pollutants and discharged by an oxidation reactor, and is the harmful gas with the largest discharge amount of a PTA device. Therefore, the discharge liquid of the PTA oxidation tail gas washing tower is also the main source of wastewater in the production process of the PTA chemical plant.
The discharge liquid of the PTA oxidation tail gas washing tower mainly contains sodium bromide, sodium bicarbonate, sodium carbonate and the like, wherein the concentration of the sodium bicarbonate in the discharge liquid of the washing tower is up to 2.0 percent, but the cobalt-manganese catalyst recovery device only needs the sodium carbonate, does not need the sodium bicarbonate, and needs to remove the sodium bicarbonate from the discharge liquid of the washing tower, the discharge liquid of the washing tower is directly discharged to a sewage treatment plant to be treated as wastewater, the wastewater treatment cost is high, and a large amount of resources are wasted. Therefore, the development of a treatment process capable of recycling sodium carbonate has important significance for the discharge liquid of the PTA oxidation tail gas washing tower.
Disclosure of Invention
In view of the above, the present invention is directed to a method and a system for separating sodium carbonate from sodium bromide in a PTA oxidation tail gas scrubber effluent, and to efficiently recover sodium carbonate in the PTA oxidation tail gas scrubber effluent during treatment.
Therefore, the invention provides a method for separating sodium carbonate and sodium bromide from the discharge liquid of a PTA oxidation tail gas washing tower, which comprises the following steps:
s1, adjusting the pH value of the washing tower effluent to 11.0-12.0 in a sodium bicarbonate removal tower by heating with steam or adding sodium hydroxide into the PTA oxidation tail gas washing tower effluent, and discharging gas generated in the process from the top of the sodium bicarbonate removal tower to obtain decarbonized washing tower effluent;
s2, conveying the decarbonized washing tower discharge liquid to an ultrafiltration device to remove suspended particles, so as to obtain ultrafiltration product water and ultrafiltration concentrated water, and discharging the ultrafiltration concentrated water;
s3, conveying the ultrafiltration produced water to a first-stage nanofiltration device to obtain first-stage nanofiltration produced water and first-stage nanofiltration concentrated water rich in sodium carbonate, and conveying the first-stage nanofiltration concentrated water to a recovery device;
s4, conveying the I-stage nanofiltration produced water to a II-stage nanofiltration device to obtain II-stage nanofiltration concentrated water and II-stage nanofiltration produced water without sodium carbonate, and conveying the II-stage nanofiltration concentrated water back to the I-stage nanofiltration device;
s5, conveying the II-stage nanofiltration produced water to an I-stage RO reverse osmosis device to concentrate a sodium bromide solution to obtain I-stage RO reverse osmosis concentrated water and I-stage RO reverse osmosis produced water, wherein the I-stage RO reverse osmosis concentrated water is a solution rich in sodium bromide;
s6, conveying the I-stage RO produced water to a II-stage RO reverse osmosis device to further recover sodium bromide therein to obtain II-stage RO reverse osmosis concentrated water and II-stage RO reverse osmosis produced water, conveying the II-stage RO reverse osmosis concentrated water to the I-stage RO reverse osmosis device, and circulating the II-stage RO reverse osmosis concentrated water to a PTA oxidation tail gas washing tower to be used as spraying liquid.
In the method for separating sodium carbonate from sodium bromide according to the present invention, in step S1, the PH of the effluent from the scrubber is preferably adjusted to 11.5 to 11.8.
In the method for separating sodium carbonate from sodium bromide according to the present invention, it is preferable that the recovery device includes a catalyst recovery device and a sodium carbonate recovery device.
In the method for separating sodium carbonate from sodium bromide according to the present invention, it is preferable that the ultrafiltration apparatus, the first-stage nanofiltration apparatus, the second-stage nanofiltration apparatus, the first-stage RO reverse osmosis apparatus, and the second-stage RO reverse osmosis apparatus are membrane apparatuses, respectively and independently.
In the method for separating sodium carbonate from sodium bromide, the membrane aperture of the ultrafiltration device is preferably 5-10 nm.
In the method for separating sodium carbonate from sodium bromide, preferably, the interception efficiency of the I-grade nanofiltration device on sodium carbonate in ultrafiltration produced water is 90-94%, and the interception efficiency of the II-grade nanofiltration device on sodium carbonate in the I-grade nanofiltration produced water is 90-94%.
In the method for separating sodium carbonate from sodium bromide, the operating pressure of the I-grade RO device is preferably 3.5-4.5MPa, and the operating pressure of the II-grade RO device is preferably 2.5-3.5 MPa.
Therefore, the invention also provides a separation system for sodium carbonate and sodium bromide in the discharge liquid of the PTA oxidation tail gas washing tower, which comprises a sodium bicarbonate removal tower, an ultrafiltration device, a first-stage nanofiltration device, a second-stage nanofiltration device, a first-stage RO reverse osmosis device and a second-stage RO reverse osmosis device, wherein the tower bottom of the sodium bicarbonate removal tower is communicated with a water inlet of the ultrafiltration device, ultrafiltration concentrated water is discharged from the ultrafiltration device, and ultrafiltration produced water is conveyed to the first-stage nanofiltration device; conveying first-stage nanofiltration concentrated water in the first-stage nanofiltration device to a recovery device, conveying first-stage nanofiltration produced water to the second-stage nanofiltration device, conveying second-stage nanofiltration concentrated water in the second-stage nanofiltration device back to the first-stage nanofiltration device, conveying second-stage nanofiltration produced water to the first-stage RO reverse osmosis device, conveying first-stage RO reverse osmosis produced water in the first-stage RO reverse osmosis device to the second-stage RO reverse osmosis device, and conveying the first-stage RO reverse osmosis concentrated water, namely sodium bromide solution; and II-stage RO reverse osmosis concentrated water in the II-stage RO reverse osmosis device is conveyed back to the I-stage RO reverse osmosis device, and II-stage RO reverse osmosis produced water is recycled back to the PTA oxidation tail gas washing tower to be used as spraying liquid.
The separation system of sodium carbonate and sodium bromide, provided by the invention, is characterized in that the recovery device preferably comprises a catalyst recovery device and a sodium carbonate recovery device; the ultrafiltration device, the first-stage nanofiltration device, the second-stage nanofiltration device, the first-stage RO reverse osmosis device and the second-stage RO reverse osmosis device are respectively and independently membrane devices; further preferably, the membrane pore size of the ultrafiltration device is 5-10 nm.
In the separation system of sodium carbonate and sodium bromide, preferably, the interception efficiency of the I-grade nanofiltration device on sodium carbonate in ultrafiltration produced water is 90-94%, and the interception efficiency of the II-grade nanofiltration device on sodium carbonate in the I-grade nanofiltration produced water is 90-94%; the operating pressure of the I-grade RO reverse osmosis device is 3.5-4.5Mpa, and the operating pressure of the II-grade RO reverse osmosis device is 2.5-3.5 Mpa.
Specifically, the method for separating sodium carbonate from sodium bromide in the discharge liquid of the PTA oxidation tail gas washing tower comprises the following steps:
(1) conveying the effluent of the washing tower to a sodium bicarbonate removal tower, heating for decarburization by exchanging heat with steam or adjusting the pH value to 11.6 or 11.7 by adding NaOH, and discharging carbon dioxide generated after removing sodium bicarbonate from the top of the sodium bicarbonate removal tower;
(2) the effluent of the washing tower after sodium bicarbonate removal enters an ultrafiltration device for pretreatment, solid impurities such as large-particle molecules, suspended matters and the like are removed, the water quality entering a subsequent system is improved, ultrafiltration product water obtained after pretreatment is sent into an ultrafiltration product water tank and an ultrafiltration concentrated water discharge device containing the solid impurities;
(3) conveying the ultrafiltration product water in the ultrafiltration product water tank to a first-stage nanofiltration device through a nanofiltration water inlet pump under pressure to separate sodium carbonate to obtain first-stage nanofiltration product water and first-stage nanofiltration concentrated water containing the sodium carbonate, and conveying the first-stage nanofiltration concentrated water to a catalyst recovery device to recover cobalt and manganese in the first-stage nanofiltration concentrated water and then recover the sodium carbonate in the first-stage nanofiltration concentrated water;
(4) conveying the I-stage nanofiltration produced water to a II-stage nanofiltration device for further separating and recovering sodium carbonate therein to obtain II-stage nanofiltration produced water and II-stage nanofiltration concentrated water, namely a sodium carbonate solution, and conveying the II-stage nanofiltration concentrated water to an ultrafiltration produced water tank for recycling;
(5) conveying the II-stage nanofiltration produced water to a nanofiltration produced water tank, and conveying the II-stage nanofiltration produced water to an I-stage RO reverse osmosis device through a pump to obtain I-stage RO reverse osmosis produced water and I-stage RO reverse osmosis concentrated water, wherein the I-stage RO reverse osmosis concentrated water is a sodium bromide solution;
(6) i level RO reverse osmosis produces water and carries II level RO reverse osmosis unit to obtain II level RO reverse osmosis concentrated water and II level RO reverse osmosis produced water, and II level RO reverse osmosis produced water is used as the supplementary liquid of PTA oxidation scrubbing tower, and II level RO reverse osmosis concentrated water is carried to receiving to strain and is produced water tank circulation and use to improve the rate of recovery of sodium bromide.
In conclusion, the beneficial effects of the invention are as follows: the process and system of the present invention can convert sodium bicarbonate in the effluent of the PTA oxidation off-gas scrubber to sodium carbonate and utilize subsequent steps to separate sodium carbonate and sodium bromide.
Drawings
FIG. 1 is a process flow diagram of the process of the present invention for separating sodium carbonate from sodium bromide in the PTA oxidation tail gas scrubber effluent.
Wherein:
1. the device comprises a sodium bicarbonate removal tower, 2, an ultrafiltration water inlet pump, 3, an ultrafiltration device, 4, an ultrafiltration water production tank, 5, a nanofiltration water inlet pump, 6, a I-level nanofiltration device, 7, a II-level nanofiltration device, 8, a nanofiltration water production tank, 9, an RO reverse osmosis feed pump, 10, an I-level RO reverse osmosis device and 11, a II-level RO reverse osmosis device.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. The present invention may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
Referring to fig. 1, when the method for separating sodium carbonate from sodium bromide in the effluent of the PTA oxidation tail gas scrubber according to the present invention is implemented in combination with a system for treating the effluent of the PTA oxidation tail gas scrubber, the method specifically comprises the following steps:
(1) the effluent of the washing tower is conveyed to a sodium bicarbonate removal tower 1, the pH value is adjusted to 11.6 or 11.7 by heating and decarbonization through heat exchange with steam or by adding NaOH, and the generated carbon dioxide gas is discharged from the top of the sodium bicarbonate removal tower 1;
(2) the effluent of the washing tower after sodium bicarbonate removal enters an ultrafiltration device 3 through an ultrafiltration water inlet pump 2 for pretreatment, solid impurities such as large-particle molecules, suspended matters and the like are removed, the water quality entering a subsequent system is improved, and ultrafiltration product water obtained after pretreatment is sent into an ultrafiltration product water tank 4 and an ultrafiltration concentrated water discharge system containing the solid impurities;
(3) conveying the ultrafiltration product water in the ultrafiltration product water tank 4 to an I-stage nanofiltration device 6 through a nanofiltration water inlet pump 5 under pressure to separate sodium carbonate to obtain I-stage nanofiltration product water and I-stage nanofiltration concentrated water containing the sodium carbonate, and conveying the I-stage nanofiltration concentrated water to a catalyst recovery device to recover cobalt and manganese in the I-stage nanofiltration concentrated water and then to recover the sodium carbonate;
(4) conveying the I-stage nanofiltration produced water to a II-stage nanofiltration device 7 for further separating and recovering sodium carbonate therein to obtain II-stage nanofiltration produced water and II-stage nanofiltration concentrated water, namely sodium carbonate solution, and conveying the II-stage nanofiltration concentrated water to an ultrafiltration produced water tank 4 for recycling;
(5) conveying the II-stage nanofiltration product water to a nanofiltration product water tank 8, conveying the II-stage nanofiltration product water to an I-stage RO reverse osmosis device 10 through an RO reverse osmosis feed pump 9 to concentrate a sodium bromide solution to obtain I-stage RO reverse osmosis concentrated water and I-stage RO reverse osmosis product water, and conveying the I-stage RO reverse osmosis concentrated water rich in sodium bromide to recycle the sodium bromide solution;
(6) the I-grade RO reverse osmosis produced water is conveyed to the II-grade RO reverse osmosis device 11 to further recover sodium bromide solution, so that II-grade RO reverse osmosis concentrated water and II-grade RO reverse osmosis produced water are obtained, the II-grade RO reverse osmosis produced water is used as supplement liquid (such as washing tower spray liquid) of a PTA oxidation washing tower, and the II-grade RO reverse osmosis concentrated water is conveyed to a nanofiltration produced water tank 8 to be recycled, so that the recovery rate of sodium bromide is improved.
Example 1:
this example is a chinese test performed with reference to the flow shown in fig. 1, and specifically includes the following steps:
(1) conveying the washing tower effluent (100kg/h) to a sodium bicarbonate removal tower 1, adjusting the pH value to 11.6 by adding NaOH, and discharging carbon dioxide generated after removing sodium bicarbonate from the top of the sodium bicarbonate removal tower;
(2) the effluent (101kg/h) of the washing tower after sodium bicarbonate removal enters an ultrafiltration device 3 for pretreatment, solid impurities such as large-particle molecules, suspended matters and the like are removed, the water quality entering a subsequent system is improved, ultrafiltration product water obtained after pretreatment is sent into an ultrafiltration product water tank 4, and ultrafiltration concentrated water (1kg/h) containing the solid impurities is discharged from the device;
(3) conveying ultrafiltration product water (100kg/h) in the ultrafiltration product water tank 4 to a first-stage nanofiltration device 6 through a nanofiltration water inlet pump 5 under pressure to separate sodium carbonate to obtain first-stage nanofiltration product water (95kg/h) and first-stage nanofiltration concentrated water (5kg/h) containing sodium carbonate, and conveying the first-stage nanofiltration concentrated water to a catalyst recovery device to recover cobalt and manganese therein and then recover sodium carbonate therein;
(4) conveying the I-grade nanofiltration produced water (95kg/h) to a II-grade nanofiltration device 7 for further separating and recovering sodium carbonate therein to obtain II-grade nanofiltration produced water (90kg/h) and II-grade nanofiltration concentrated water (5kg/h), namely sodium carbonate solution, and conveying the II-grade nanofiltration concentrated water to an ultrafiltration produced water tank 4 for recycling so as to improve the recovery rate of the sodium carbonate;
(5) recycling II-stage nanofiltration produced water (90kg/h) to a nanofiltration produced water tank 8, conveying to an I-stage RO reverse osmosis device 10 through an RO reverse osmosis feed pump 9 to concentrate a sodium bromide solution to obtain I-stage RO reverse osmosis concentrated water and I-stage RO reverse osmosis produced water, and conveying the I-stage RO reverse osmosis concentrated water rich in sodium bromide to the outside to recycle the sodium bromide solution;
(6) and (3) conveying the I-grade RO reverse osmosis produced water (85kg/h) to a II-grade RO reverse osmosis device 11 to further recover a sodium bromide solution to obtain II-grade RO reverse osmosis concentrated water (5kg/h) and II-grade RO reverse osmosis produced water (81kg/h), wherein the II-grade RO reverse osmosis produced water is used as a supplementary liquid of the PTA oxidation washing tower, and the II-grade RO reverse osmosis concentrated water (4kg/h) is conveyed to a nanofiltration produced water tank 8 to be recycled so as to improve the recovery rate of the sodium bromide.
Wherein, the recovery rate of the embodiment is shown in table 1, and the operation condition of the sodium bicarbonate removal tower 1 is shown in table 2. The membrane unit operating conditions are seen in table 2.
Recovery of the test of the formula in Table 1
| Serial number | Item | Index (I) |
| 1 | Sodium carbonate recovery rate of nanofiltration device | 95.0％ |
| 2 | Recovery rate of sodium bromide | 93.0％ |
TABLE 2 Membrane plant operating conditions
In table 1, the nanofiltration device recovered sodium carbonate (nanofiltration water inflow x nanofiltration water sodium carbonate content-nanofiltration water outflow x nanofiltration water outflow sodium carbonate content)/(nanofiltration water inflow x inflow sodium carbonate content);
for the above formula, in example 1, the nanofiltration influent water is ultrafiltration product water, the nanofiltration effluent water is II-stage nanofiltration product water, and the ultrafiltration product water and the II-stage nanofiltration product water have sodium carbonate contents.
In table 1, the recovery rate of sodium bromide (high-pressure reverse osmosis concentrated water yield × high-pressure reverse osmosis concentrated water sodium bromide content)/(device water intake × device water sodium bromide content).
In table 2, the operating conditions of the nanofiltration device are those of both the stage i nanofiltration device and the stage ii nanofiltration device.
As can be seen from tables 1 to 2, the conventional process flow of treating the effluent of the PTA oxidation off-gas washing tower is direct discharge disposal, and sodium carbonate in the effluent of the PTA oxidation off-gas washing tower is not recovered, which causes a great deal of resource waste, but the present invention adopts equipment such as a sodium bicarbonate removal tower, an ultrafiltration water inlet pump, an ultrafiltration device, an ultrafiltration water production tank, a nanofiltration water inlet pump, a first-stage nanofiltration device, a second-stage nanofiltration device, a nanofiltration water production tank, an RO reverse osmosis feed pump 0, a first-stage RO reverse osmosis device, a second-stage RO reverse osmosis device, etc., so that sodium bicarbonate in the effluent of the PTA oxidation off-gas washing tower can be converted into sodium carbonate and separated from sodium bromide, and cobalt, manganese precious metals and sodium carbonate in the effluent are further recovered by a recovery unit.
It should be noted that the above preferred embodiments are only for illustrating the present invention, but the present invention is not limited to the above embodiments, and variations and modifications within the spirit of the present invention, which are made by those skilled in the art, are included in the protection scope of the present invention.
Claims (10)
1. A method for separating sodium carbonate and sodium bromide from PTA oxidation tail gas washing tower discharge liquid is characterized by comprising the following steps:
s1, adjusting the pH value of the washing tower effluent to 11.0-12.0 in a sodium bicarbonate removal tower by heating with steam or adding sodium hydroxide into the PTA oxidation tail gas washing tower effluent, and discharging gas generated in the process from the top of the sodium bicarbonate removal tower to obtain decarbonized washing tower effluent;
s2, conveying the decarbonized washing tower discharge liquid to an ultrafiltration device to remove suspended particles, so as to obtain ultrafiltration product water and ultrafiltration concentrated water, and discharging the ultrafiltration concentrated water;
s3, conveying the ultrafiltration produced water to a first-stage nanofiltration device to obtain first-stage nanofiltration produced water and first-stage nanofiltration concentrated water rich in sodium carbonate, and conveying the first-stage nanofiltration concentrated water to a recovery device;
s4, conveying the I-stage nanofiltration produced water to a II-stage nanofiltration device to obtain II-stage nanofiltration concentrated water and II-stage nanofiltration produced water without sodium carbonate, and conveying the II-stage nanofiltration concentrated water back to the I-stage nanofiltration device;
s5, conveying the II-stage nanofiltration produced water to an I-stage RO reverse osmosis device to concentrate a sodium bromide solution to obtain I-stage RO reverse osmosis concentrated water and I-stage RO reverse osmosis produced water, wherein the I-stage RO reverse osmosis concentrated water is a solution rich in sodium bromide;
s6, conveying the I-stage RO produced water to a II-stage RO reverse osmosis device to further recover sodium bromide therein to obtain II-stage RO reverse osmosis concentrated water and II-stage RO reverse osmosis produced water, conveying the II-stage RO reverse osmosis concentrated water to the I-stage RO reverse osmosis device, and circulating the II-stage RO reverse osmosis concentrated water to a PTA oxidation tail gas washing tower to be used as spraying liquid.
2. The method of claim 1, wherein the PH of the scrubber effluent is adjusted to 11.5 to 11.8 in step S1.
3. The process of claim 1, wherein the recovery unit comprises a catalyst recovery unit and a sodium carbonate recovery unit.
4. The method of claim 1, wherein the ultrafiltration unit, the first-stage nanofiltration unit, the second-stage nanofiltration unit, the first-stage RO reverse osmosis unit, and the second-stage RO reverse osmosis unit are membrane units.
5. The resource treatment method according to claim 4, wherein the membrane pore size of the ultrafiltration device is 5 to 10 nm.
6. The resource treatment method according to claim 1, wherein the retention efficiency of the grade I nanofiltration device on sodium carbonate in ultrafiltration product water is 90-94%, and the retention efficiency of the grade II nanofiltration device on sodium carbonate in the grade I nanofiltration product water is 90-94%.
7. The resource treatment method as claimed in claim 1, wherein the operating pressure of the first-stage RO reverse osmosis device is 3.5-4.5MPa, and the operating pressure of the second-stage RO reverse osmosis device is 2.5-3.5 MPa.
8. A separation system for sodium carbonate and sodium bromide in a discharge liquid of a PTA oxidation tail gas washing tower is characterized by comprising a sodium bicarbonate removal tower, an ultrafiltration device, a first-stage nanofiltration device, a second-stage nanofiltration device, a first-stage RO reverse osmosis device and a second-stage RO reverse osmosis device, wherein the tower bottom of the sodium bicarbonate removal tower is communicated with a water inlet of the ultrafiltration device, an ultrafiltration concentrated water discharge device is arranged in the ultrafiltration device, and ultrafiltration produced water is conveyed to the first-stage nanofiltration device; conveying first-stage nanofiltration concentrated water in the first-stage nanofiltration device to a recovery device, conveying first-stage nanofiltration produced water to the second-stage nanofiltration device, conveying second-stage nanofiltration concentrated water in the second-stage nanofiltration device back to the first-stage nanofiltration device, conveying second-stage nanofiltration produced water to the first-stage RO reverse osmosis device, conveying first-stage RO reverse osmosis produced water in the first-stage RO reverse osmosis device to the second-stage RO reverse osmosis device, and conveying the first-stage RO reverse osmosis concentrated water, namely sodium bromide solution; and II-stage RO reverse osmosis concentrated water in the II-stage RO reverse osmosis device is conveyed back to the I-stage RO reverse osmosis device, and II-stage RO reverse osmosis produced water is recycled back to the PTA oxidation tail gas washing tower to be used as spraying liquid.
9. The system for separating sodium carbonate from sodium bromide according to claim 8, wherein the recovery unit comprises a catalyst recovery unit and a sodium carbonate recovery unit; the ultrafiltration device, the first-stage nanofiltration device, the second-stage nanofiltration device, the first-stage RO reverse osmosis device and the second-stage RO reverse osmosis device are respectively and independently membrane devices; preferably, the membrane pore size of the ultrafiltration device is 5-10 nm.
10. The system for separating sodium carbonate from sodium bromide according to claim 8, wherein the retention efficiency of the grade I nanofiltration device on sodium carbonate in ultrafiltration product water is 90-94%, and the retention efficiency of the grade II nanofiltration device on sodium carbonate in the grade I nanofiltration product water is 90-94%; the operating pressure of the I-grade RO reverse osmosis device is 3.5-4.5Mpa, and the operating pressure of the II-grade RO reverse osmosis device is 2.5-3.5 Mpa.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115414692A (en) * | 2022-11-01 | 2022-12-02 | 浙江百能科技有限公司 | Method and device for separating sodium carbonate by melting and thermal crystallization of PTA incineration ash |
| CN115893452A (en) * | 2022-11-17 | 2023-04-04 | 浙江百能科技有限公司 | Method and device for separating and purifying sodium carbonate and sodium bromide from PTA (pure terephthalic acid) alkali recovery furnace ash solution |
| CN116550118A (en) * | 2023-07-09 | 2023-08-08 | 浙江百能科技有限公司 | Integrated separation device and method for activating absorption crystallization |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115414692A (en) * | 2022-11-01 | 2022-12-02 | 浙江百能科技有限公司 | Method and device for separating sodium carbonate by melting and thermal crystallization of PTA incineration ash |
| CN115893452A (en) * | 2022-11-17 | 2023-04-04 | 浙江百能科技有限公司 | Method and device for separating and purifying sodium carbonate and sodium bromide from PTA (pure terephthalic acid) alkali recovery furnace ash solution |
| CN116550118A (en) * | 2023-07-09 | 2023-08-08 | 浙江百能科技有限公司 | Integrated separation device and method for activating absorption crystallization |
| CN116550118B (en) * | 2023-07-09 | 2023-09-22 | 浙江百能科技有限公司 | Integrated separation device and method for activating absorption crystallization |
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