Development of a Concentration Measurement System for Pickling Line Control

산세라인 자동화를 위한 농도 측정 시스템 개발

  • 박형국 (POSCO 시스템설계연구그룹) ;
  • 이종현 (POSCO 시스템설계연구그룹) ;
  • 노일환 (POSCO 시스템설계연구그룹)
  • Received : 2013.04.12
  • Accepted : 2013.09.02
  • Published : 2013.10.01


This paper proposes the development of a new method for online analysis which measured acid concentration in a pickling line. Pickling is the most important step to remove surface scale layers and is strongly depending on the exactly controlled pickling liquor composition. Today, there is no feasible system available for the online control of pickling lines. Within this paper, new methods for online analysis of pickling liquors have been tested and implemented into an overall pickling process control tool. This method measured simultaneously the hydrochloric acid and iron ion concentration in a solution of hydrochloric acid by measuring the ultrasonic speed, the solution temperature, and the electrical conductivity. Experimental results showed excellent precision and the measurement error was ${\pm}2g/l$ compared with the neutralization titration measurement.


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