CN115784163A - Terminal judgment method for producing sodium hypochlorite by caustic soda chlorination method - Google Patents
Terminal judgment method for producing sodium hypochlorite by caustic soda chlorination method Download PDFInfo
- Publication number
- CN115784163A CN115784163A CN202211582166.XA CN202211582166A CN115784163A CN 115784163 A CN115784163 A CN 115784163A CN 202211582166 A CN202211582166 A CN 202211582166A CN 115784163 A CN115784163 A CN 115784163A
- Authority
- CN
- China
- Prior art keywords
- chlorine
- sodium hypochlorite
- reaction
- end point
- introducing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 title claims abstract description 114
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 title claims abstract description 72
- 239000005708 Sodium hypochlorite Substances 0.000 title claims abstract description 71
- 235000011121 sodium hydroxide Nutrition 0.000 title claims abstract description 38
- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 26
- 238000005660 chlorination reaction Methods 0.000 title claims abstract description 14
- 238000006243 chemical reaction Methods 0.000 claims abstract description 97
- 239000000460 chlorine Substances 0.000 claims abstract description 73
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims abstract description 72
- 229910052801 chlorine Inorganic materials 0.000 claims abstract description 72
- 239000007788 liquid Substances 0.000 claims abstract description 37
- 239000003513 alkali Substances 0.000 claims abstract description 22
- 230000000630 rising effect Effects 0.000 claims abstract description 14
- 238000010521 absorption reaction Methods 0.000 claims abstract description 4
- KZBUYRJDOAKODT-UHFFFAOYSA-N Chlorine Chemical compound ClCl KZBUYRJDOAKODT-UHFFFAOYSA-N 0.000 claims description 35
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 12
- 229910052757 nitrogen Inorganic materials 0.000 claims description 6
- 239000000463 material Substances 0.000 claims description 5
- -1 hydrogen ions Chemical class 0.000 claims description 4
- 239000001257 hydrogen Substances 0.000 claims description 3
- 229910052739 hydrogen Inorganic materials 0.000 claims description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims 1
- 239000011734 sodium Substances 0.000 claims 1
- 229910052708 sodium Inorganic materials 0.000 claims 1
- 238000005070 sampling Methods 0.000 description 9
- 238000004458 analytical method Methods 0.000 description 8
- 238000012544 monitoring process Methods 0.000 description 3
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 238000009776 industrial production Methods 0.000 description 2
- BZSXEZOLBIJVQK-UHFFFAOYSA-N 2-methylsulfonylbenzoic acid Chemical compound CS(=O)(=O)C1=CC=CC=C1C(O)=O BZSXEZOLBIJVQK-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 235000011194 food seasoning agent Nutrition 0.000 description 1
- 239000012458 free base Substances 0.000 description 1
- WQYVRQLZKVEZGA-UHFFFAOYSA-N hypochlorite Inorganic materials Cl[O-] WQYVRQLZKVEZGA-UHFFFAOYSA-N 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/141—Feedstock
Abstract
The invention discloses an end point judgment method for producing sodium hypochlorite by a caustic soda chlorination method, which comprises the following steps: preparing a dilute NaOH solution with a target concentration according to a production task, and adding the dilute NaOH solution into a reaction tank; starting a pump to circulate the dilute NaOH solution in the reaction tank through a Venturi tube and generate negative pressure; opening a valve for introducing chlorine, introducing the chlorine with stable flow into the Venturi tube, and carrying out mixed absorption reaction on the chlorine and the dilute NaOH solution in the Venturi tube to generate sodium hypochlorite and fall into a reaction tank; comprehensively judging whether the reaction for producing sodium hypochlorite in the reaction tank reaches the end point according to the rising amount of the liquid level in the reaction tank, the potential value and the total amount of the introduced chlorine. The method comprehensively judges the reaction end point of producing the sodium hypochlorite from the amount of the introduced chlorine, the potential value and the liquid level increment, can effectively improve the quality of the produced sodium hypochlorite, can more accurately control the amount of alkali and chlorine, controls the production cost and realizes the automatic production of the sodium hypochlorite.
Description
Technical Field
The invention relates to the technical field of sodium hypochlorite industrial production, in particular to an end point judgment method for producing sodium hypochlorite by a caustic soda chlorination method.
Background
The production of sodium hypochlorite is generally carried out by adopting a seasoning tower in the chlor-alkali industry, the main quality requirement of the sodium hypochlorite is that the concentration of free alkali is 0.1-1 percent, the concentration of effective chlorine is more than 5 percent, more than 10 percent and more than 13 percent, wherein the index concentration of the free alkali is NaOH + Cl reaction 2 ＝NaClO+NaCl+H 2 And (3) judging whether the O (caustic soda solution chlorination method) reaches an end point. The direct control parameter for producing sodium hypochlorite by the caustic soda solution chlorination method is the residual sodium hydroxide solute, when the mass fraction of the sodium hydroxide solute in a reaction system is 0.1-1%, the reaction is considered to reach the end point, and if chlorine is continuously introduced, the over-chlorination reaction occurs
The balance moves reversely, the chlorine cannot be absorbed by the solution, the solution is acidic, hypochlorite ions in the solution are changed into chlorine and diffuse to the gas phase, and safety and environmental protection accidents are caused.
In order to determine whether the chemical reaction reaches the end point, two major types of determination methods exist in the industry: direct judgment of reaction end point, and manual sampling analysis.
A method for directly judging a reaction end point: in the process of continuously introducing chlorine gas in the reaction, in order to obtain the concentration of free alkali in the sodium hypochlorite solution, a free alkali online monitoring instrument is additionally arranged or a manual sampling analysis mode is adopted in the industry, so that the concentration of the free alkali is obtained. The concentration of free alkali in a reaction system can be directly monitored by on-line monitoring of the free alkali, the concentration of the free alkali in the reaction system can be determined after debugging, the cost of the on-line monitoring of the free alkali on the market is about 40 ten thousand yuan, and the investment cost of instruments is too high.
Manual sampling analysis: generally, a post operator informs a laboratory of sampling analysis according to experience, in order to ensure that the reaction is not over chlorinated, the operator generally determines the reaction process of the free alkali concentration to 2% -3% according to the experience, the first sampling analysis is performed, the chlorine gas introduction amount is reduced, the experience determines that the free alkali concentration is 0.1% -1%, the second sampling analysis is performed, and the chlorine gas is closed; if the chlorine gas is not qualified, opening the small-gas-volume chlorine gas, continuing the reaction, and informing the laboratory of sampling and analyzing for the third time, and so on. Because the industrial production process is influenced by multiple factors, the experience judgment of operators has deviation, the product quality is qualified only through sampling analysis for many times, the experience judgment is only suitable for producing sodium hypochlorite products with the same concentration, if the concentration of the added raw materials is not controlled stably, the accuracy of the manual experience judgment is lost, only manual sampling analysis can be carried out, and the operation intensity of the operators is increased.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides the end point judgment method for producing sodium hypochlorite by the caustic soda chlorination method, which realizes automatic production of sodium hypochlorite.
In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows:
the end point judgment method for producing sodium hypochlorite by a caustic soda chlorination method comprises the following steps:
s1: preparing dilute NaOH solution with target concentration according to production task, adding the dilute NaOH solution into the reaction tank through a quick-opening valve, and collecting initial liquid level H of the reaction tank by a liquid level sensor 1 ；
S2: starting a pump to circulate the dilute NaOH solution in the reaction tank through a Venturi tube and generate negative pressure;
s3: opening a valve for introducing chlorine, introducing the chlorine with stable flow into a Venturi tube, and carrying out mixing absorption reaction on the chlorine and a dilute NaOH solution in the Venturi tube to generate sodium hypochlorite which falls into a reaction tank;
s4: comprehensively judging whether the reaction for producing sodium hypochlorite in the reaction tank reaches the end point according to the rising amount of the liquid level in the reaction tank, the potential value and the total amount of introduced chlorine, if so, entering the step S5, and otherwise, continuing the reaction;
s5: after the reaction reaches the end point, closing the valve for introducing chlorine, opening the valve for introducing nitrogen into the Venturi tube, and introducing nitrogen into the Venturi tube to prevent sodium hypochlorite from being sucked backwards;
s6: and after the reaction is finished, opening a pump to pour the sodium hypochlorite finished product into a finished product tank.
Further, step S4 includes:
s41: and (3) calculating the total amount L of the introduced chlorine gas according to the chlorine flow L recorded by the chlorine flow sensor and the time t of the introduced chlorine gas along with the continuous introduction of the chlorine gas: l = L × t;
s42: calculating the total amount L' of the chlorine needed under the theory according to the total amount of the diluted NaOH solution with the target concentration prepared in the step S1;
s43: judging the size of the total amount L of the introduced chlorine and the total amount L' of the chlorine needed under the theoretical condition:
if L is less than L', judging that the reaction for producing the sodium hypochlorite does not reach the end point, and continuously introducing chlorine;
if L is more than or equal to L ', the reaction for producing sodium hypochlorite is judged to possibly reach the end point, and the difference value delta L between the total amount L of the introduced chlorine and the total amount L' of the chlorine required under the theoretical condition is calculated: Δ L = L-L'; the difference value delta L and the allowable fluctuation value delta L of the introduced chlorine gas are compared Wave motion And (3) comparison:
if Δ L > Δ L Wave motion Closing the valve for introducing the chlorine gas and stopping introducing the chlorine gas; if Δ L is less than or equal to Δ L Wave motion If yes, the chlorine gas can be continuously introduced, and the step S44 is executed;
s44: the liquid level sensor collects the liquid level H in the reaction tank at the moment 2 Calculating the amount delta H of liquid level rising in the reaction tank in the process of generating sodium hypochlorite: Δ H = H 2 -H 1 ；
Comparing the amount of liquid level rising Δ H with the ideal value of liquid level rising Δ H Ideal for Comparing; if Δ H.gtoreq.Δ H Ideal for Judging that the reaction of the sodium hypochlorite produced at this time reaches the end point, and closing a valve for introducing chlorine; if Δ H < Δ H Ideal for If so, judging that the reaction for producing the sodium hypochlorite can reach the end point, and executing the step S45;
s45: the potential value d in the reaction tank at this time was measured by a Nernst type potentiometer 1 Introducing chlorine at the momentThe total amount L of gas and the amount of diluted NaOH solution with the prepared target concentration are calculated by using a theoretical material balance formula to obtain the free alkali content a in the sodium hypochlorite OH- ；
Estimation of theoretical potential d in potential sodium hypochlorite by Nernst equation Estimating ：d Estimating ＝K-0.0592lga H+ (ii) a Wherein a is H+ Is the content of hydrogen ions in sodium hypochlorite, a H+ ＝a OH- K is a standard potential value;
the potential value d 1 And theoretical potential d Estimating And (4) performing difference to obtain a potential fluctuation value delta d: Δ d = | d Estimating -d 1 |；
If Δ d is less than or equal to Δ d Threshold value If the reaction of the sodium hypochlorite produced at this time is judged to reach the end point, a valve for introducing chlorine is closed, and the step S5 is executed; if Δ d > Δ d Threshold value If the reaction of the sodium hypochlorite produced at this time does not reach the end point, the chlorine gas can be continuously introduced, the step S41 is returned, and delta d is carried out Threshold value The threshold value of the potential fluctuation allowed at the end of the sodium hypochlorite production reaction.
The invention has the beneficial effects that: the method comprehensively judges the reaction end point of producing the sodium hypochlorite according to the amount of the introduced chlorine, the potential value and the liquid level increment, avoids misjudgment while ensuring the complete reaction effect, can monitor whether the reaction reaches the end point in real time in the process of introducing the chlorine for reaction, ensures that the chlorine is cut off in time after the reaction end point is reached, can effectively improve the quality of the produced sodium hypochlorite, can more accurately control the amount of alkali and chlorine and control the production cost. In the process of executing the reaction end point judgment, the amount of the introduced chlorine is taken as a reference, the potential value and the liquid level increment are taken as auxiliary criteria, and the judgment basis for the end point reached by the reaction can be taken as long as the requirements of the amount of the chlorine + the potential value or the amount of the chlorine + the liquid level increment are met, so that the reaction end point is flexibly controlled and has high precision.
Drawings
FIG. 1 is a flow chart of an end point judgment method for producing sodium hypochlorite by a caustic soda chlorination method.
Detailed Description
The following description of the embodiments of the present invention is provided to facilitate the understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and it will be apparent to those skilled in the art that various changes may be made without departing from the spirit and scope of the invention as defined and defined by the appended claims, and all changes that can be made by the invention using the inventive concept are intended to be protected.
As shown in fig. 1, the method for judging the end point of sodium hypochlorite production by the caustic soda chlorination method comprises the following steps:
s1: preparing dilute NaOH solution with target concentration according to production task, adding the dilute NaOH solution into the reaction tank by quickly opening a valve, and collecting initial liquid level H of the reaction tank by a liquid level sensor 1 ；
S2: starting a pump to circulate the dilute NaOH solution in the reaction tank through a Venturi tube and generate negative pressure;
s3: opening a valve for introducing chlorine, introducing the chlorine with stable flow into the Venturi tube, and carrying out mixed absorption reaction on the chlorine and the dilute NaOH solution in the Venturi tube to generate sodium hypochlorite and fall into a reaction tank;
s4: comprehensively judging whether the reaction for producing sodium hypochlorite in the reaction tank reaches the end point or not according to the rising amount of the liquid level in the reaction tank, the potential value and the total amount of introduced chlorine, if so, entering the step S5, otherwise, continuing the reaction; step S4 specifically includes:
s41: and (3) calculating the total amount L of the introduced chlorine gas according to the chlorine flow L recorded by the chlorine flow sensor and the time t of the introduced chlorine gas along with the continuous introduction of the chlorine gas: l = L × t;
s42: calculating the total amount L' of the chlorine needed under the theory according to the total amount of the diluted NaOH solution with the target concentration prepared in the step S1;
s43: judging the size of the total amount L of the introduced chlorine and the total amount L' of the chlorine required under the theoretical condition:
if L is less than L', judging that the reaction for producing the sodium hypochlorite does not reach the end point, and continuously introducing chlorine gas;
if L is more than or equal to L', the reaction for producing sodium hypochlorite can reachCalculating the difference delta L between the total amount L of the introduced chlorine and the total amount L' of the chlorine required under theoretical conditions: Δ L = L-L'; the difference value Delta L and the allowable fluctuation value Delta L of the introduced chlorine gas are compared Wave motion And (3) comparison:
if Δ L > Δ L Wave motion Closing the valve for introducing the chlorine gas and stopping introducing the chlorine gas; if Δ L is less than or equal to Δ L Wave motion If yes, continuing to introduce chlorine gas, and executing step S44;
s44: the liquid level sensor collects the liquid level H in the reaction tank at the moment 2 Calculating the amount delta H of liquid level rising in the reaction tank in the process of generating sodium hypochlorite: Δ H = H 2 -H 1 ；
Comparing the amount of liquid level rising Δ H with the ideal value of liquid level rising Δ H Ideal for Carrying out comparison; if Δ H.gtoreq.Δ H Is ideally of Judging that the reaction of the sodium hypochlorite produced at the time reaches the end point, and closing a valve for introducing chlorine; if Δ H < Δ H Is ideally of If so, judging that the reaction for producing the sodium hypochlorite can reach the end point, and executing the step S45;
s45: the potential value d in the reaction tank at this time was measured by a Nernst type potentiometer 1 Calculating the content a of free alkali in the sodium hypochlorite at the moment by using a theoretical material balance formula according to the total amount L of the chlorine gas introduced at the moment and the amount of the diluted NaOH solution with the prepared target concentration OH- ；
Estimation of theoretical potential d in potential sodium hypochlorite by Nernst equation Estimating ：d Estimating ＝K-0.0592lga H+ (ii) a Wherein a is H+ Is the content of hydrogen ions in sodium hypochlorite, a H+ ＝a OH- K is a standard potential value;
the potential value d 1 And theoretical potential d Estimating And (4) performing difference to obtain a potential fluctuation value delta d: Δ d = | d Estimating -d 1 |；
If Δ d is less than or equal to Δ d Threshold value Judging that the reaction of the sodium hypochlorite produced at this time reaches the end point, closing a valve for introducing chlorine, and executing the step S5; if Δ d > Δ d Threshold value If the reaction of the sodium hypochlorite produced at this time is judged not to reach the end point, the chlorine gas can be continuously introduced, the step S41 is returned, and delta d Threshold value For the production timeThe threshold value of the potential fluctuation allowed at the end of the sodium chlorate reaction.
S5: after the reaction reaches the end point, closing the valve for introducing chlorine, opening the valve for introducing nitrogen into the Venturi tube, and introducing nitrogen into the Venturi tube to prevent sodium hypochlorite from being sucked backwards;
s6: after the reaction is finished, a pump is opened to pour the sodium hypochlorite finished product into a finished product tank.
The method comprehensively judges the reaction end point of producing the sodium hypochlorite according to the amount of the introduced chlorine, the potential value and the liquid level increment, avoids misjudgment while ensuring the complete reaction effect, can monitor whether the reaction reaches the end point in real time in the process of introducing the chlorine for reaction, ensures that the chlorine is cut off in time after the reaction end point is reached, can effectively improve the quality of the produced sodium hypochlorite, can more accurately control the amount of alkali and chlorine, and can control the production cost. In the process of judging the reaction end point, the amount of the introduced chlorine is taken as a reference, the potential value and the liquid level increment are taken as auxiliary criteria, and the judgment basis for the reaction end point can be taken as long as the requirements of the amount of the chlorine plus the potential value or the amount of the chlorine plus the liquid level increment are met, so that the control of the reaction end point is flexible and the precision is high.
In this embodiment, taking the end point judgment method for producing sodium hypochlorite by a caustic soda chlorination method according to the present invention as an example, validity of the process for producing sodium hypochlorite is demonstrated through data of actual production:
(1) index of chlorine accumulation
Initially: the mass of the dilute alkali solution is 18.8 tons, and the concentration of the prepared alkali is 13.5 percent.
And (3) reaction end point: the chlorine flow rate was predicted to be 532.8m3, the free base concentration 0.87%, and the effective chlorine concentration 10.51%. The mass balance is shown in Table 1 below:
TABLE 1 material balance data sheet
According to the actual test result, 0.99% of free alkali, 10.21% of available chlorine, 537.17m3 of chlorine gas are introduced cumulatively, the reaction time is 2.4h, and the difference from the theoretical calculation result is small.
(2) Index of electric potential value
According to the theoretical material balance formula, the end point value is 0.87 percent of free alkali, the potential is estimated by adopting the Nernst equation, d Estimating ＝K-0.0592lga H+ ，d Estimating =518.87mv, actual result 529mv. The end point potentials of the actual process are shown in table 2 below:
TABLE 2ORP potential values and end-point test results table
As is clear from Table 2 above, the potential value at the end of the reaction was about 520mv, and the potential fluctuation was small.
(3) Level value index
According to production data, the liquid level will rise by 5% -10%, the initial liquid level 70.39%, and the end liquid level 80.12%. The end point control index is set as liquid level 80%, potential value index 520mv, and chlorine gas integrated value 532.8m3.
Table 3 liquid level rising data table
As shown in Table 3 above, the liquid level rises in the range of 5% to 7.9%. The summary of control parameters is shown in table 4 below:
TABLE 4 production control index summary sheet
Claims (2)
1. An end point judgment method for producing sodium hypochlorite by a caustic soda chlorination method is characterized by comprising the following steps:
s1: preparing dilute NaOH solution with target concentration according to production task, adding the dilute NaOH solution into the reaction tank through a quick-opening valve, and collecting initial liquid level H of the reaction tank by a liquid level sensor 1 ；
S2: starting a pump to circulate the dilute NaOH solution in the reaction tank through a Venturi tube and generate negative pressure;
s3: opening a valve for introducing chlorine, introducing the chlorine with stable flow into the Venturi tube, and carrying out mixed absorption reaction on the chlorine and the dilute NaOH solution in the Venturi tube to generate sodium hypochlorite and fall into a reaction tank;
s4: comprehensively judging whether the reaction for producing sodium hypochlorite in the reaction tank reaches the end point or not according to the rising amount of the liquid level in the reaction tank, the potential value and the total amount of introduced chlorine, if so, entering the step S5, otherwise, continuing the reaction;
s5: after the reaction reaches the end point, closing a valve for introducing chlorine, opening a valve for introducing nitrogen into the Venturi tube, and introducing nitrogen into the Venturi tube to prevent sodium hypochlorite from being sucked back;
s6: after the reaction is finished, a pump is opened to pour the sodium hypochlorite finished product into a finished product tank.
2. The method for judging the endpoint of sodium hypochlorite production by the caustic soda chlorination method according to claim 1, wherein the step S4 comprises:
s41: and (3) calculating the total amount L of the introduced chlorine gas according to the chlorine flow L recorded by the chlorine flow sensor and the time t of the introduced chlorine gas along with the continuous introduction of the chlorine gas: l = L × t;
s42: calculating the total amount L' of the chlorine needed theoretically according to the total amount of the diluted NaOH solution with the target concentration prepared in the step S1;
s43: judging the size of the total amount L of the introduced chlorine and the total amount L' of the chlorine required under the theoretical condition:
if L is less than L', judging that the reaction for producing the sodium hypochlorite does not reach the end point, and continuously introducing chlorine gas;
if L is more than or equal to L', judging that the reaction for producing the sodium hypochlorite can reach the end point, and calculating the introduced chlorineThe difference Δ L between the total amount L of chlorine and the total amount L' of chlorine required under theoretical conditions: Δ L = L-L'; the difference value Delta L and the allowable fluctuation value Delta L of the introduced chlorine gas are compared Wave motion And (3) comparison:
if Δ L > Δ L Wave motion Closing the valve for introducing the chlorine gas and stopping introducing the chlorine gas; if Δ L is less than or equal to Δ L Wave motion If yes, the chlorine gas can be continuously introduced, and the step S44 is executed;
s44: the liquid level sensor collects the liquid level H in the reaction tank at the moment 2 Calculating the amount delta H of liquid level rising in the reaction tank in the process of generating sodium hypochlorite: Δ H = H 2 -H 1 ；
Comparing the rising amount of the liquid level Delta H with the ideal rising amount Delta H Is ideally of Comparing; if Δ H.gtoreq.Δ H Is ideally of Judging that the reaction of the sodium hypochlorite produced at this time reaches the end point, and closing a valve for introducing chlorine; if Δ H < Δ H Is ideally of If so, judging that the reaction for producing the sodium hypochlorite is possible to reach the end point, and executing a step S45;
s45: the potential value d in the reaction tank at this time was measured by a Nernst type potentiometer 1 Calculating the total amount L of chlorine gas and the amount of diluted NaOH solution with the target concentration by using a theoretical material balance formula to obtain the free alkali content a in the sodium hypochlorite OH- ；
Estimation of theoretical potential d in potential sodium hypochlorite by Nernst equation Estimating ：d Estimating ＝K-0.0592lga H+ (ii) a Wherein a is H+ Is the content of hydrogen ions in sodium hypochlorite, a H+ ＝a OH- K is a standard potential value;
the potential value d 1 And theoretical potential d Estimating And (4) obtaining a potential fluctuation value delta d: Δ d = | d Estimating -d 1 |；
If Δ d is less than or equal to Δ d Threshold value If the reaction of the sodium hypochlorite produced at this time is judged to reach the end point, a valve for introducing chlorine is closed, and the step S5 is executed; if Δ d > Δ d Threshold value If the reaction of the sodium hypochlorite produced at this time is judged not to reach the end point, the chlorine gas can be continuously introduced, the step S41 is returned, and delta d Threshold value Potential value allowed at the end of the reaction for producing sodium hypochloriteA fluctuation threshold.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211582166.XA CN115784163B (en) | 2022-12-09 | 2022-12-09 | Terminal judgment method for sodium hypochlorite production by caustic soda chlorination process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211582166.XA CN115784163B (en) | 2022-12-09 | 2022-12-09 | Terminal judgment method for sodium hypochlorite production by caustic soda chlorination process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115784163A true CN115784163A (en) | 2023-03-14 |
| CN115784163B CN115784163B (en) | 2024-01-30 |
Family
ID=85418363
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211582166.XA Active CN115784163B (en) | 2022-12-09 | 2022-12-09 | Terminal judgment method for sodium hypochlorite production by caustic soda chlorination process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115784163B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117742278A (en) * | 2024-02-07 | 2024-03-22 | 四川飞洁科技发展有限公司 | Intelligent monitoring and management method and system for sodium hypochlorite production process |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101226640B1 (en) * | 2012-08-14 | 2013-01-25 | 주식회사 제이텍 | Device for generating high-concentrated sodium hypochlorite |
| CN103241713A (en) * | 2013-05-15 | 2013-08-14 | 乳源东阳光电化厂 | Preparation method of sodium hypochlorite |
| WO2018026260A1 (en) * | 2016-08-05 | 2018-02-08 | Cheng Chew Kong | System and method for recovering sodium hypochlorite from exhaust chlorine gas |
-
2022
- 2022-12-09 CN CN202211582166.XA patent/CN115784163B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101226640B1 (en) * | 2012-08-14 | 2013-01-25 | 주식회사 제이텍 | Device for generating high-concentrated sodium hypochlorite |
| CN103241713A (en) * | 2013-05-15 | 2013-08-14 | 乳源东阳光电化厂 | Preparation method of sodium hypochlorite |
| WO2018026260A1 (en) * | 2016-08-05 | 2018-02-08 | Cheng Chew Kong | System and method for recovering sodium hypochlorite from exhaust chlorine gas |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117742278A (en) * | 2024-02-07 | 2024-03-22 | 四川飞洁科技发展有限公司 | Intelligent monitoring and management method and system for sodium hypochlorite production process |
| CN117742278B (en) * | 2024-02-07 | 2024-04-30 | 四川飞洁科技发展有限公司 | Intelligent monitoring and management method and system for sodium hypochlorite production process |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115784163B (en) | 2024-01-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102589963B (en) | Methods for digesting and detecting titanium concentrate, titanium slag or titanium carbide slag | |
| CN115784163B (en) | Terminal judgment method for sodium hypochlorite production by caustic soda chlorination process | |
| JP5284196B2 (en) | Method for quantitative analysis of selenium | |
| Endrődi et al. | Suppressed oxygen evolution during chlorate formation from hypochlorite in the presence of chromium (VI) | |
| US20160061791A1 (en) | Automatic Ammonium Analyzer | |
| US3199949A (en) | Process control for hypochlorite production | |
| NO133834B (en) | ||
| JP5859287B2 (en) | Method for measuring the concentration of trace hydrogen peroxide in ultrapure water | |
| US20120181182A1 (en) | Electrolytic Apparatus, System and Method for the Safe Production of Nitrogen Trifluoride | |
| JP6462402B2 (en) | Sodium chloride concentration analysis method, sodium chloride concentration analyzer and sodium hypochlorite analyzer | |
| US6653142B1 (en) | Automatic determination of the contamination of aqueous cleaning solutions with carbonaceous compounds | |
| JPH0526853A (en) | Method for measuring main constituent concentration of neutral salt electrolytic bath for descaling stainless steel band | |
| JP4617153B2 (en) | Trace chlorine ion concentration analysis method | |
| EP0466303B1 (en) | Method and system for continuously monitoring and controlling a process stream for dechlorination residual | |
| Asakai | Characterization of oxyanions of chlorine by multipath titrimetric approach for drinking water quality control | |
| WO2020028069A2 (en) | Methods of generating and testing aqueous gas streams | |
| JP3196181B2 (en) | Reaction endpoint control method using ORP electrode | |
| JP6975406B2 (en) | A method for controlling the amount of aluminum dissolved and a method for producing gypsum based on the method. | |
| KR102178443B1 (en) | Method for quantification analysis of iron oxides on steel surface using glow discharge optical emission spectrometry with multivariate analysis | |
| RU2499622C1 (en) | Method for controlling degree of electrolyte depletion in combined electrochemical air regeneration systems for submarines | |
| Cowell et al. | A New Improved Method for the Determination of Sodium Hydroxide Current Efficiency in Membrane Cells | |
| US20040256069A1 (en) | Estimation and control in the wet end using CO2 | |
| CN115190967A (en) | Automatic sugar feeding | |
| CN116395725A (en) | Production of fluorochemicals by means of electrochemical measuring chains | |
| CN112485316A (en) | Electrochemical titration method for testing total chlorine in industrial monobutyl tin oxide |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |