High-precision on-line analysis system and method for amount of excessive alkali

Abstract

The invention discloses a high-precision on-line analysis system for the amount of excessive alkali. The high-precision on-line analysis system includes a rack, wherein an analysis cabin is fixed on the rack; a pretreatment filtering device and an analyzer host are fixed in the analysis cabin; the analyzer host comprises a host case, a display screen is arranged on the host case, an analysis system and an electric control system are arranged in the host case; the analysis system comprises an excessive alkali amount detector, a feeding device and a discharging device; the excessive alkali amount detector comprises a sample cup and a test assembly, the test assembly comprises a reagent dropwise adding device and a tester; the invention also provides a high-precision on-line analysis method for the amount of excessive alkali. The analysis method comprises the following steps: cleaning impurities such as silt, introducing a solution to be detected into a pretreatment filtering device, cleaning the sample cup of the excessive alkali amount detector, quantifying a solution in the sample cup, detecting the content of sodium hydroxide and sodium carbonate, and cleaning the excessive alkaliamount detector. According to the method, the contents of sodium hydroxide and sodium carbonate can be simultaneously and respectively detected, the detection precision and efficiency are improved, and the cost is reduced; the service life of equipment is prolonged, and automatic control is realized.

Description

technical field [0001] The invention belongs to the field of chemical analysis, and in particular relates to a high-precision online analysis system and method for excess alkalinity. Background technique [0002] At present, the primary brine in the chlor-alkali industry is coarse brine, which contains a lot of sand and pebbles, and the calcium and magnesium ions in the coarse brine exceed the standard, so it is necessary to add an excessive amount of Na 2 CO 3 Reaction and precipitation removal with NaOH requires real-time monitoring of the content of Na2CO3 and NaOH. Now manual sampling and filtration analysis is frequent, the workload is heavy, and the analysis accuracy is not enough. If the amount of Na2CO3 and NaOH is too small, the calcium and magnesium in brine will exceed the standard, affecting the entire system, Na 2 CO 3 Too much addition of NaOH will cause waste. On the one hand, it will increase the amount of acid used for subsequent treatment. On the other h...

AI Technical Summary

Problems solved by technology

[0002] At present, the primary brine in the chlor-alkali industry is coarse brine, which contains a lot of sand and pebbles, and the calcium and magnesium ions in the coarse brine exceed the standard, so it is necessary to add an excessive amount of Na 2 CO 3 Reaction and precipitation removal with NaOH requires real-time monitoring of the content of Na2CO3 and NaOH. Now manual sampling and filtration analysis is frequent, the workload is heavy, and the analysis accuracy is not enough. If the amount of Na2CO3 and NaOH is too small, the calcium and magnesium in brine will exceed the standard, affecting the entire system, Na 2 CO 3 Too much addition of NaOH will cause waste. On the one hand, it will increase the amount of acid used for subsequent treatment. On the other hand, the electrolytic cell will also increase the side reactions and affect the quality of the entire system and products. The applicant applied for it in 2015 and made it public later. The patent No. 201520183410.4 is an on-line analyzer for excessive alkalinity, which includes a box body. The box body is equipped with a control system and a detection system. The control system is connected to and controls the detection system. The detection system includes a reaction cup, a micro-feeding Pump, PH meter, quantitative system, feeding system and discharging system, the applicant applied for and published in 2017 the application number 201710572442.7 on-line analyzer for over-alkali content, including a shell, a control device placed in the shell module and operation module; the operation module is used for on-line analysis of the amount of excess alkali, and the above two technical solutions cannot perform pretreatment such as recoil and filtration on the solution to be measured because there is no pretreatment filter device and pure water decompression system As well as cleaning the tested detector, it seriously affects the detection accuracy and the service life of the equipment. More importantly, the basic principle of the above scheme is to neutralize with hydrochloric acid, and then detect with a pH meter. During the detection process, often Large deviations have seriously affected the detection accuracy, and the instrument has a single function. When customers need to detect the concentration, they often need to purchase additional equipment and install it separately, which increases equipment investment, occupies the space of the production site, and increases production costs. Conducive to production automation

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