CO Measurement of PCI in Steel Plant

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Prevent Self-ignition of Pulverized Coal with a Fast Measurement Time of Less than 2 Seconds



Pulverized coal piled up in bag filters (dust collectors) can cause self-ignition in pulverized coal injection (PCI) facilities at steel plants, and that is a safety concern. It can prevent ignition by measuring and monitoring carbon monoxide (CO) concentration continuously. An upward trend in CO is a sign of self-ignition. However, the conventional method is not suitable for CO measurement, because it requires a sample conditioning system (SCS) before measurement, resulting in response delays and increased maintenance costs and man-hours. The TDLS8000 laser gas analyzer can solve this problem efficiently. It can be installed directly in the process without a SCS, resulting in fast measurement and a significant reduction in running costs.


Customer’s Expectation

  • Safe operation of PCI facilities (prevention of self-ignition)
  • Early detection of pulverized coal self-ignition
  • CO concentration meter with fast response and continuous measurement
  • Reduction of SCS maintenance costs and man-hours


Process Overview

Pulverized coal is provided to the blast furnace. A bag filter is set to remove pulverized coal in the exhaust line of the storage tank. Piled-up pulverized coal can self-ignite in a high-temperature environment. Temperature and CO concentration are measured to prevent ignition.

Process Overview

Solution Provided by Yokogawa

TDLS8000 can detect CO concentration quickly by in-situ measurement. That means catching the signs of self-ignition in pulverized coal piled up in bag filters and taking the necessary action immediately. Also, TDLS needs only slight maintenance due to non-sampling and non-consumption parts.


Advantages of TDLS8000

  • Fast response - direct measurement of process gas
  • Slight maintenance - non-sampling
  • Accurate measurement of low concentration - reference cell installation
Solution provided by Yokogawa

Measurement System

  • Model & Suffix Code
    • TDLS8000-G2-C2-□*1)- A1-J-N/RC/**2)
    • Unit connection cable:K9775□*3)
  • Utility
    • Recommended purge gasses*4)
      N2(more than 99.99%)or instrument air
    • Purge gas flow rates*4)
      Optic: 2~20 L/min
      Process gas window(one side):typ. 5~50 L/min *4)
    • Power supply;24 V DC ± 10%

Measurement system

    • *1) depends on flange size
      *2) option code(if needed)
      *3) depends on cable length
      *4) depends on the application
  • Note
    • Please use clean and dry purge gas.
    • Please select -C2 instead of -C1 for TDLS gas code.
    • Please check the CO2 and H2O concentration in the process gas and write them on the application datasheet.


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