JP2016198697A5

JP2016198697A5 -

Info

Publication number: JP2016198697A5
Application number: JP2015078978A
Authority: JP
Filing date: 2015-04-08
Publication date: 2018-03-08
Anticipated expiration: 2035-04-08

Description

［有機酸溶液分解方法］
まず始めにシュウ酸１ａ及びギ酸１ｂを混合槽３にそれぞれ注入し、混合する。そして、混合溶液を配管５を介して分解槽９に移送する。その移送過程の途中（ギ酸分解部５ａ）で過酸化水素水注入装置４によって過酸化水素水を注入し、ギ酸の大部分を分解する。ギ酸の大部分が分解された有機酸溶液を分解槽９に収容し、分解槽９において、オゾン発生装置６ａで発生させたオゾンを有機酸溶液に注入する。分解槽９には測定装置８ａが設置されており、その測定された値（信号）を基に、オゾン注入量制御装置６ｂにて分解槽９に注入するオゾン量（濃度）が制御されるシステムとなっている。 [Organic acid solution decomposition method]
First, oxalic acid 1a and formic acid 1b are respectively injected into the mixing tank 3 and mixed. Then, the mixed solution is transferred to the decomposition tank 9 through the pipe 5. In the middle of the transfer process (formic acid decomposition part 5a), hydrogen peroxide solution is injected by the hydrogen peroxide solution injection device 4 to decompose most of the formic acid. The organic acid solution were largely degraded in formic acid containing the decomposition tank 9, in the decomposition tank 9, to inject ozone generated by the ozone generator 6 a to the organic acid solution. A measuring device 8a is installed in the decomposition tank 9, and the ozone amount (concentration) injected into the decomposition tank 9 is controlled by the ozone injection amount control device 6b based on the measured value (signal). It has become.

（３）オゾン注入速度の決定
ステンレス鋼の電位は先に示した図３及び図４のとおり、オゾン注入速度及びシュウ酸濃度によって決定される。図６はステンレス鋼の電位を０．８Ｖとしたときのオゾン注入速度のシュウ酸濃度依存性を示すグラフである。図６から、分解槽９のシュウ酸濃度に応じてオゾン注入量を制御すれば、ステンレス鋼の電位を腐食抑制臨界値（０．８Ｖ）以下に保ち、腐食を軽減させることが可能となる。なお、図６は温度を６０℃で一定に保ったときのグラフである。図６のグラフは当然温度に依存するものであるが、ここで温度を６０℃としているのは、シュウ酸をオゾンで分解する際に最も効率良く分解できるのが６０℃であり、分解槽は基本的に６０℃に制御されているためである。したがって、一般的には温度変化でオゾン流量を変化させる制御は必要では無いが、分解槽９に測定装置として温度センサーを追加し、その信号を元にオゾン注入量制御装置６ｂでオゾン注入量を制御することも可能である。 (3) Determination of ozone injection rate The potential of stainless steel is determined by the ozone injection rate and the oxalic acid concentration as shown in FIGS. FIG. 6 is a graph showing the oxalic acid concentration dependence of the ozone injection rate when the potential of stainless steel is 0.8V. From FIG. 6, if the ozone injection amount is controlled according to the oxalic acid concentration in the decomposition tank 9, the potential of the stainless steel can be kept below the corrosion inhibition critical value (0.8 V) and the corrosion can be reduced. FIG. 6 is a graph when the temperature is kept constant at 60.degree. The graph of FIG. 6 naturally depends on the temperature. Here, the temperature is set to 60 ° C., and when the oxalic acid is decomposed with ozone, it can be decomposed most efficiently at 60 ° C. This is because the temperature is basically controlled at 60 ° C. Therefore, although in general not necessary control for changing the ozone flow rate temperature changes, adding a temperature sensor and the measurement equipment in the decomposition vessel 9, the ozone with an ozone injection rate control device 6b on the basis of the signal It is also possible to control the injection amount.

図２は、本発明に係る有機酸溶液分解システムの第２の例を示すブロック図である。図２に示す有機酸溶液分解システム１００ｂにおいて、図１に示す有機酸溶液分解処理装置１００ａと異なる部分は、配管５の途中に触媒層５ｂを設けている点と、分解槽９の測定装置８ｂをサンプリング部（サンプリングユニット）１０と分析部１１とで構成した点にある。 FIG. 2 is a block diagram showing a second example of the organic acid solution decomposition system according to the present invention. In the organic acid solution decomposition system 100b shown in FIG. 2, the difference from the organic acid solution decomposition processing apparatus 100a shown in FIG. 1 is that a catalyst layer 5b is provided in the middle of the pipe 5, and a measuring device 8b of the decomposition tank 9. Is composed of a sampling unit ( sampling unit ) 10 and an analysis unit 11.

Claims

A decomposition tank containing an organic acid solution containing a carboxylic acid;
An ozone injection device for injecting ozone into the organic acid solution;
A measuring device for measuring at least one parameter of the potential of the decomposition tank, the pH of the organic acid solution, the carboxylic acid concentration or the carbon dioxide concentration,
The organic acid solution decomposition system, wherein the ozone injection device controls an injection amount of ozone based on a value measured by the measurement device .

The organic acid solution decomposition system according to claim 1, wherein the carboxylic acid is formic acid and oxalic acid.

The measuring device has a sampling unit and an analysis unit,
The sampling unit collects a part of the organic acid solution,
The organic acid solution decomposition system according to claim 1, wherein the analysis unit performs the measurement on a part of the collected organic acid solution.

2. The organic acid solution decomposition system according to claim 1, wherein the ozone injection device controls an injection amount of ozone at a time when the measured value starts to change.

The organic acid solution decomposition system according to claim 1, wherein the ozone injection device controls an injection amount of ozone in accordance with a change amount of the measured value .

The ozone injection device obtains a corrosion inhibition critical value of the parameter calculated from a relationship between the corrosion potential of the decomposition tank measured in advance and the corrosion potential and the parameter, and the parameter is equal to or less than the corrosion inhibition critical value. The organic acid solution decomposition system according to claim 1, wherein the ozone injection amount is controlled so that

An organic acid solution containing carboxylic acid is placed in a decomposition tank,
The measurement device measures at least one parameter of the potential of the decomposition tank, the pH of the organic acid solution, the carboxylic acid concentration or the carbon dioxide concentration,
In injection amount determined based on the measurement value of the parameter, the organic acid solution cracking process, characterized in that the ozone injection device to inject ozone into the organic acid solution disassembly of the carboxylic acid.

The organic acid solution decomposition method according to claim 7, wherein the carboxylic acid is formic acid and oxalic acid.

The organic acid solution decomposition method according to claim 7, wherein the measurement is performed by collecting a part of the organic acid solution.

The injection amount of the ozone, measured organic acid solution decomposition method according to claim 7, wherein the controller controls when the value began to change.

8. The organic acid solution decomposition method according to claim 7, wherein the ozone injection amount is controlled in accordance with the measured change amount of the value .

Obtain the corrosion inhibition critical value of the parameter calculated from the corrosion potential of the decomposition tank measured in advance, and the relationship between the corrosion potential and the parameter, and inject the ozone so that the parameter is equal to or less than the corrosion inhibition critical value. 8. The organic acid solution decomposition method according to claim 7, wherein the amount is controlled.