JP2018523128A - Peracid washing inhibitor analyzer and peracid washing analysis method using the same - Google Patents

Abstract

An invention relating to an apparatus for analyzing an acid pickling inhibitor and a method for analyzing an acid pickling inhibitor using the same is disclosed. In one specific example, the peracid wash inhibitor analyzer includes a first reaction part including a first inflow part, a second inflow part, a third inflow part, and a fourth inflow part. , A fifth inflow part, a sixth inflow part, a seventh inflow part, a second reaction part comprising a pH measurement part and a level measurement part, and electrically connected to the pH measurement part and the level measurement part A control operation unit.

Description

  The present invention relates to an apparatus for analyzing an acid pickling inhibitor and a method for analyzing an acid pickling inhibitor using the apparatus. More specifically, the present invention relates to a concentration analysis apparatus for an amine compound contained in a peracid washing inhibitor used in a pickling rolling process at the time of manufacturing a cold-rolled steel sheet, and a peracid washing analysis method using the same.

  The cold rolling process is a process of rolling a steel material that has been hot-rolled at a temperature near room temperature, and is a stage for producing a product with a beautiful surface and excellent workability. In the cold rolling process, the hot rolled coil is subjected to pickling and rolling equipment, and then the final product is produced through equipment such as galvanization or cold rolling.

  In the pickling rolling equipment, the oxide adhering to the surface of the hot-rolled steel sheet is pickled and removed, and then continuously rolled to a desired thickness at room temperature to produce a semi-finished product. Hydrochloric acid is used for the purpose.

  Background art related to the present invention is disclosed in Korean Patent Publication No. 2004-0017751 (published on February 27, 2004, title of invention: pickling method for hot-rolled steel sheet).

  According to an embodiment of the present invention, an anti-pickling agent analyzer excellent in reliability, accuracy and precision is provided.

  According to one embodiment of the present invention, there is provided an apparatus for analyzing an anti-pickling agent which prevents cold pickling of a cold-rolled steel sheet and has an excellent surface defect prevention effect.

  According to one embodiment of the present invention, there is provided a peracid wash inhibitor analyzer capable of improving the work efficiency during the pickling process.

  According to an embodiment of the present invention, there is provided a method for analyzing a peracid washing inhibitor using the peracid washing agent analyzer.

One aspect of the present invention relates to a peracid wash inhibitor analyzer. In one specific example, the peracid wash inhibitor analyzer includes a first inflow portion into which a peracid wash inhibitor containing an amine compound flows, a second inflow portion into which a decomposition agent flows, and SHST (sodium hydroxide- a third inflow portion into which a solution of sodium thiosulfate) and a fourth inflow portion into which water flows are provided, and a decomposition agent is added to the peracid wash inhibitor and heated to decompose the peracid wash inhibitor. A first reaction part for flowing the SHST solution and water into the decomposed peracid washing inhibitor to generate ammonia (NH ₃ ) by distillation; and an ammonia distilled in the first reaction part 5 inflow parts, a sixth inflow part into which boric acid flows in, a seventh inflow part into which sulfuric acid flows in, a pH measurement part for measuring the internal pH, and a level measurement part for measuring the internal level are provided. Said inflow Ammonia is collected with boric acid to produce a collection solution, and the second reaction unit that flows in the sulfuric acid and titrates the collection solution is electrically connected to the pH measurement unit and the level measurement unit, And a control calculation unit for transmitting the measured pH and level data inside the second reaction unit and analyzing the concentration of the peracid washing inhibitor.

Another aspect of the present invention relates to a peracid washing inhibitor analysis method using the peracid washing inhibitor analyzer. In one specific example, the method for analyzing a peracid wash inhibitor includes a step of adding a decomposition agent to a peracid wash inhibitor containing an amine compound and decomposing it by heating, and adding SHST to the decomposed peracid wash inhibitor. (Sodium hydride-sodium thiosulfate) solution and adding water and collecting the ammonia (NH ₃ ) generated by distillation, collecting the collected ammonia (NH ₃ ) with boric acid, collecting the collected solution And deriving the concentration of nitrogen contained in the ammonia (NH ₃ ) by titrating the collected solution with sulfuric acid, wherein the decomposition agent is potassium sulfate (K ₂ SO ₄ ). , Copper sulfate (CuSO ₄ ), sulfuric acid (H ₂ SO ₄ ) and water.

  In one specific example, the heating may be performed at 350 ° C to 400 ° C.

  In one embodiment, the distillation may be performed at 60 ° C to 100 ° C.

  In one embodiment, the titration includes measuring the pH of the boric acid and adding sulfuric acid to the collection solution to adjust the pH of the collection solution to the measured boric acid pH. It may be performed including.

  When applying the method for analyzing a peracid washing inhibitor of the present invention, it is excellent in the reliability, accuracy and precision of the concentration measurement of the amine compound contained in the peracid washing agent, and is suitable for peracid washing of cold-rolled steel sheets. Therefore, it is excellent in the effect of preventing surface defects and can improve the work efficiency during the pickling process.

1 shows an apparatus for analyzing an anti-pickling agent according to an embodiment of the present invention. 1 shows a method for analyzing an anti-pickling agent according to an embodiment of the present invention. It is the graph which compared the density | concentration of the amine compound contained in the prepared peracid wash inhibitor and the measured peracid wash inhibitor.

  In describing the present invention, if it is determined that a specific description of the known technique or configuration can unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

  The terms to be described later are defined in consideration of the functions in the present invention, and may be different depending on the intention of the user, the operator, the customs, etc. Must be based on the content of the entire book.

Peracid Washing Analyzing Device One aspect of the present invention relates to peroxidation preventing agent analysis standing. FIG. 1 shows an anti-pickling agent analyzer 1000 according to an embodiment of the present invention. Referring to FIG. 1, the peracid washing agent analyzer 1000 according to the present invention includes a first inflow part 1 into which a peracid washing inhibitor containing an amine compound stored in the sample storage part 201 flows, and a decomposition. A second inflow part 2 into which the decomposition agent stored in the agent storage part 202 flows in; a third inflow part 3 into which an SHST (sodium hydride-sodium thiosulfate) solution stored in the SHST storage part 203 flows in; and a water storage part And a fourth inflow part 4 into which the water stored in 204 flows in, and a decomposition agent is introduced from the second inflow part 2 to the peracid wash preventing agent that has flowed in from the first inflow part 1 and heated. The peracid washing inhibitor is decomposed, and the SHST solution and water from the fourth inflow part 4 are allowed to flow into the decomposed peracid washing inhibitor and water is distilled from the fourth inflow part 4 to generate ammonia (NH ₃ ). First reaction unit 10 1, a fifth inflow part 5 into which ammonia distilled in the first reaction part 101 flows in, a sixth inflow part 6 into which boric acid stored in the boric acid storage part 205 flows, and a sulfuric acid storage part 206. A seventh inflow section 7 into which the sulfuric acid flows in, a pH measurement section 301 for measuring the internal pH, and a level measurement section 302 for measuring the internal level are provided, and the ammonia that has flowed in through the fifth inflow section 5 is provided. A second reaction unit 102 that collects boric acid flowing in through the sixth inflow part 6 to produce a collection solution, and injects sulfuric acid through the seventh inflow part 7 to titrate the collected solution; and the pH measurement A control calculation unit 103 that is electrically connected to the unit 301 and the level measurement unit 302 and transmits the measured pH and level data in the second reaction unit 102 to analyze the concentration of the peracid washing inhibitor. Including.

  In the present invention, the first reaction unit 101 is provided with a heater (not shown), and a heating agent (not shown) is added to the decomposition agent and heated, and the SHST solution and water are added to perform distillation. Is called. Moreover, although not shown in figure, the waste gas processing part is provided in the 1st reaction part 101 side, and an unreacted waste gas is discharged | emitted.

  Referring to FIG. 1, in one embodiment of the present invention, a first discharge unit 21 and a second discharge unit 22 are provided on one side of the first reaction unit 101 and the second reaction unit 102, respectively. Components remaining in the first reaction unit 101 and the second reaction unit 102 can be discharged. For example, it can be discharged using the principle of siphon.

  Referring to FIG. 1, the water stored in the water storage unit 204 may flow into the sample storage unit 201 through the eighth inflow unit 8 to dilute the peracid wash inhibitor. Since the concentration of the amine compound (HMTA) contained in the peracid washing inhibitor may be different, the amount of water is injected in a dilutable manner such as 5 times, 10 times, 20 times, 50 times and 100 times depending on the sample injection sample And the optimum concentration can be converted.

  Further, the water stored in the water storage unit 204 flows into the second reaction unit 102 through the ninth inflow unit 9 to adjust the concentration of the collected solution or to wash the inside of the second reaction unit 102. be able to.

  In one specific example, the pH measurement unit 301 measures the pH of boric acid flowing from the boric acid storage unit 205 through the sixth inflow unit 6 into the second reaction unit 102 and flows into the boric acid through the fifth inflow unit 5. Sulfuric acid can be introduced into the collection solution generated by collecting the collected ammonia through the seventh inflow portion 7 to measure the pH of the collection solution.

  The level measuring unit 302 measures the level of boric acid that has flowed into the second reaction unit 102 from the boric acid storage unit 205 through the sixth inflow unit 6, and collected by collecting the ammonia in the boric acid. It is possible to measure the level of the solution and the level of the collection solution that is titrated by adding the sulfuric acid.

The control calculation unit 103 can derive the concentration of nitrogen contained in the peracid washing preventing agent using the pH data of the pH measurement unit 301 and the level data measured by the level measurement unit 302.

  In one specific example, each of the first to ninth inflow portions may be provided with a pump, and the pump is electrically connected to the control calculation unit 103 and can be controlled.

Method for Analyzing Peracid Washing Agent Another aspect of the present invention relates to a method for analyzing an acid pickling inhibitor using the peracid washing agent analyzer. FIG. 2 shows a method for analyzing a peracid washing inhibitor according to an embodiment of the present invention. Referring to FIG. 2, the method for analyzing a peracid wash inhibitor includes (s101) a peracid wash decomposition step, (s102) an ammonia collection step, (s103) a collected solution manufacturing step, and (s104). ) A titration step.

More specifically, the method for analyzing an anti-pickling agent comprises: (s101) a step of adding a decomposing agent to an anti-pickling agent containing an amine compound and heating to decompose; and (s102) the decomposition. A step of adding SHST (sodium hydride-sodium thiosulfate) solution and water to the peracid pickling inhibitor and collecting ammonia (NH ₃ ) generated by distillation; (s103) boring the collected ammonia (NH ₃ ) Collecting with an acid to produce a collected solution; and (s104) titrating the collected solution with sulfuric acid to derive a concentration of nitrogen contained in the ammonia (NH ₃ ).

  Hereinafter, the method for analyzing an acid pickling agent according to the present invention will be described in detail step by step.

(S101) Peracid wash preventing agent heating step The above step is a step of adding a decomposing agent to the peracid wash preventing agent containing the amine compound and heating to decompose. In the step, the peracid washing inhibitor and the decomposition agent react to generate decomposition, oxidation, and reduction reactions.
It is required to control the acid concentration of the acid tank, which is the direct cause of unpickling and over-pickling that occurs depending on the concentration of acid used in the pickling process, and over-pickling prevention is required to prevent over-pickling. Agent is used.

  In one specific example of the present invention, a normal compound can be used as the amine compound contained in the peracid washing inhibitor. For example, hexamethylenetetraamine (HMTA) may be used.

In one embodiment, the digestion may be prepared by mixing potassium sulfate (K ₂ SO ₄ ), copper sulfate (CuSO ₄ ), sulfuric acid (H ₂ SO ₄ ), and water. In one embodiment, the decomposition agent is prepared by dissolving 134 g of potassium sulfate (K ₂ SO ₄ ) and 7.3 g of copper sulfate (CuSO ₄ ) in 800 mL of water, and then adding 134 mL of 90% sulfuric acid, It can be manufactured by diluting.

  At this time, the potassium sulfate serves to promote decomposition by dissolving in sulfuric acid to raise the boiling point.

  The heating temperature may be 350 ° C to 400 ° C. When heating in the above range, decomposition of the peracid washing inhibitor can easily proceed while preventing thermal decomposition of nitrogen contained in the peracid washing inhibitor. For example, it may be 380 ° C to 400 ° C.

The nitrogen component contained in the peracid washing inhibitor reacts with the decomposition agent to produce ammonia (NH ₃ ), and the ammonia reacts with the decomposition agent sulfuric acid (H ₂ SO ₄ ) to produce ammonium sulfate ( (NH ₄ ) ₂ SO ₄ ) is produced.

(S102) Ammonia collection step The step is a step of collecting an ammonia (NH ₃ ) gas generated by adding an SHST (sodium hydride-sodium thiosulfate) solution and water to the decomposed peracid washing inhibitor and distilling. is there.

The solution of SHST (sodium hydroxide-sodium thiosulfate, NaOH) contains sodium hydroxide and sodium thiosulfate (Na ₂ S ₂ O ₃ .5H ₂ O).

In one embodiment, the SHST solution is prepared by dissolving 500 g of the sodium hydroxide (NaOH) and 25 g of the sodium thiosulfate (Na ₂ S ₂ O ₃ · 5H ₂ O) in water and adding water to dilute to 1 L. Can be manufactured.

The distillation can be performed using a normal method. The distillation may be performed at 60 ° C to 100 ° C. When distilling at the above temperature, the ammonia (NH ₃ ) gas collecting effect can be excellent.

(S103) Collection Solution Production Step The step is a step of collecting the collected ammonia (NH ₃ ) with boric acid to generate a collection solution. When the boric acid is used, the ammonia can be easily collected, and the amount of nitrogen contained in the peracid washing inhibitor can be easily analyzed.

(S104) Titration step The step is a step of deriving the concentration of nitrogen contained in the ammonia (NH ₃ ) by titrating the collected solution with sulfuric acid. For example, the amount of nitrogen contained in the collected ammonia can be calculated from the amount of sulfuric acid consumed during the titration.

  In one embodiment, dilute sulfuric acid can be used as the sulfuric acid. For example, 0.01 N to 0.05 N (normality) sulfuric acid can be used.

  In one embodiment, the titration includes measuring the pH of the boric acid and adding sulfuric acid to the collection solution to adjust the pH of the collection solution to the measured boric acid pH. It may be performed including.

  When applying the method for analyzing the peracid wash inhibitor of the present invention, applying a method for measuring and analyzing nitrogen contained in amines, the quantitation limit is low, and even when the sample to be analyzed is based on an acid solution, It has the advantage that it can be detected, has excellent reliability, accuracy, and precision in the concentration measurement of the per-acid pickling agent. Work efficiency during the process can be improved.

  Hereinafter, the configuration and operation of the present invention will be described in more detail through preferred embodiments of the present invention. However, this is presented as a preferred example of the present invention and should not be construed as limiting the invention in any way.

EXAMPLE The nitrogen concentration of the peracid washing inhibitor was analyzed using a peracid washing inhibitor analyzer as shown in FIG.

  5 ml of a peracid washing inhibitor sample containing hexamethylenetetraamine (HMTA) stored in the sample storage unit 201 was introduced into the first reaction unit 101 through the first inflow unit 1. At this time, the first discharge part 21 of the first reaction part 101 was closed, and the gas outflow part was discharged through a waste gas treatment part (not shown).

In addition, 134 g of potassium sulfate (K ₂ SO ₄ ) and 7.3 g of copper sulfate (CuSO ₄ ) were dissolved in 800 mL of water, and then 134% of 90% sulfuric acid was added and diluted to 1 L with water again to decompose the solution. Prepare a SHST solution by dissolving 500 g of the sodium hydroxide (NaOH) and 25 g of the sodium thiosulfate (Na ₂ S ₂ O ₃ .5H ₂ O) in water and adding water to dilute to 1 L. did.

Next, 5 mL of the decomposition agent stored in the decomposition agent storage unit 202 flowed into the first reaction unit 101 through the second inflow unit 2. Thereafter, the heater was operated, and the inside of the first reaction unit 101 was heated to 390 ° C. for 10 minutes and then cooled for 5 minutes. 5 mL of boric acid stored in the boric acid storage unit 205 was added to the second reaction unit 102, and the pH of the boric acid was measured by the pH measurement unit 301. 30 mL of distilled water stored in the water storage unit 204 flows into the first reaction unit 101 through the fourth inflow unit 4, and 5 mL of the SHST solution stored in the SHST solution storage unit 203 enters through the third inflow unit 3. After that, it is heated to 100 ° C. and evaporated, and the generated ammonia (NH ₃ ) is collected through the fifth inflow part 5 and flows into the second reaction part 102, and is collected with boric acid. Was generated. When the level inside the second reaction unit 102 measured by the level measurement unit 302 reached 20 mL, the operation of the heater was stopped.

  Next, sulfuric acid stored in the sulfuric acid storage unit 206 was introduced into the collection solution through the seventh inflow unit 7, and the pH of the collection solution was adjusted to the pH of the measured boric acid and titrated.

  At this time, the pH measurement unit 301 and the level measurement unit 302 measure the pH and level of the titrated collection solution, and the control calculation unit 103 electrically connected to the pH measurement unit 301 and the level measurement unit 302 sent.

  Included in the peracid wash inhibitor using the pH data of the collected solution measured by the pH measuring unit 301 and the level data of the titrated collected solution measured by the level measuring unit 302 in the control calculation unit 103 The total nitrogen concentration was derived and shown in Table 1 below.

  Using the results analyzed as in the above Examples, the results were derived by converting the units into amine compound concentrations and are shown in Table 1 below.

  FIG. 3 is a graph comparing the concentrations of amine compounds contained in the prepared peracid wash inhibitor and the measured peracid wash inhibitor. Referring to Table 1 and FIG. 3, the result of actual data analysis shows an accuracy of 92%, the accuracy is measured within 3%, and the peracid wash inhibitor analyzer of the present invention is used. It was found that when the analysis method used was applied, the precision and accuracy were excellent when analyzing the concentration of the amine compound contained in the peracid washing inhibitor.

  Simple variations and modifications of the present invention can be easily implemented by those having ordinary knowledge in the art, and all such modifications and changes can be considered to be included in the scope of the present invention.

Claims (5)

A first inflow portion into which an anti-pickling agent containing an amine compound flows, a second inflow portion into which a decomposition agent flows, a third inflow portion into which an SHST (sodium hydroxide-sodium thiosulfate) solution flows, and water And a fourth inflow part that flows in. A decomposition agent is added to the peracid washing inhibitor and heated to decompose the peracid washing inhibitor, and the decomposed peracid washing agent includes the SHST solution and A first reaction section for flowing water and distilling to generate ammonia (NH ₃ );
A fifth inflow portion into which ammonia distilled in the first reaction portion flows, a sixth inflow portion into which boric acid flows, a seventh inflow portion into which sulfuric acid flows, and a pH measurement portion that measures the internal pH; And a level measuring unit for measuring the internal level, collecting the inflowed ammonia with boric acid to form a collected solution, and flowing in the sulfuric acid to titrate the collected solution. And
A control operation unit that is electrically connected to the pH measurement unit and the level measurement unit, and that transmits the measured pH and level data inside the second reaction unit and analyzes the concentration of the peracid wash inhibitor. An anti-pickling agent analyzer characterized by the above. Adding a decomposing agent to the peracid wash inhibitor containing an amine compound and heating to decompose,
Adding ammonia (NH ₃ ) generated by adding SHST (sodium hydroxide-sodium thiosulfate) solution and water to the decomposed peracid wash inhibitor and distilling;
Collecting the collected ammonia (NH ₃ ) with boric acid to produce a collected solution;
Titrating the collected solution with sulfuric acid to derive a concentration of nitrogen contained in the ammonia (NH ₃ ),
The method according to claim 1, wherein the decomposition agent is produced by mixing potassium sulfate (K ₂ SO ₄ ), copper sulfate (CuSO ₄ ), sulfuric acid (H ₂ SO ₄ ) and water.   The method for analyzing an anti-pickling agent according to claim 2, wherein the heating is performed at 350C to 400C.   The method for analyzing an anti-pickling agent according to claim 2, wherein the distillation is performed at 65 to 100 ° C. The titration measures the pH of the boric acid, and
The method according to claim 2, further comprising the step of adding sulfuric acid to the collection solution to adjust the pH of the collection solution to the pH of the measured boric acid. Agent analysis method.