PCI Flow Meter - Coal Flow Measurement for Blast Furnaces

Pulverized coal injection (PCI) is a process to substitute metallurgical coke by feeding coal into the blast furnace as an alternative fuel with the benefit of immense cost savings. The finely ground coal is transported by a pneumatic conveying system and distributed to multiple tuyeres. During this process the mass flow of coal is measured by means of inline flow meters. The coal flow measurement can be integrated at different stages depending on the PCI system design.

Reasons to measure the coal flow rate in PCI systems

-          The inline coal flow measurement enables the control of injection rates and the optimized utilization of coal.

-          Coal quality can change and so the injection rates must be adjusted. An inline mass flow measurement helps to maintain the desired amount of injected coal and ensures stable heat inside the blast furnace.

-          The distribution of coal into the different tuyeres is an important factor to balance the heat distribution inside the blast furnace. The PCI flow meter can measure the coal flow in each tuyere.

-          Deviations from the expected flow rates can indicate potential issues or inefficiencies in the system like clogging of the tuyeres which can lead to timely troubleshooting and maintenance.

Measuring the mass flow of coal in PCI is vital for ensuring efficient heat control, optimizing fuel usage and improving production quality in blast furnaces.

How is an inline flow meter applied in PCI systems?

The inline flow meter DYNAmas is based on capacitance measurement technology which is best suited for the process conditions in PCI plants. It provides a non-intrusive measurement, the coal flow is not disturbed and the device is maintenance-free. The flow meter is flange mounted (available in different diameters, DIN and ANSI standard) and can be easily installed in existing PCI systems as a retrofit solution.

There are mainly two ways of measuring mass flow of coal in the PCI system:

1. The basic application is the coal flow measurement in the main feeding line prior to the distributor. In this setup the total amount of coal can be controlled.
2. In the advanced application the inline flow meters are installed after the distributor so that each injection line can be controlled independently. The second approach is definitely more efficient in terms of heat control and transparency.

The output of the flow meter relates to the coal flow in kg/h or tonnes/h. The measured value is transmitted to the customer's DCS via a 4-20 mA current output so that the dosing of the coal dust can be controlled centrally from there.

As a special feature density compensation is possible, which increases the accuracy in situations where coal quality changes a lot.

How operators benefit from the PCI flow meter DYNAmas?

-          The coal flow is measured inline and with high precision providing a reliable control of injection rates

-          The flow measurement allows to control both - the total amount of injected coal and the coal flow in each tuyere

-          The inline flow meter can be easily integrated in existing PCI systems – with minimum effort and downtime

DYNAmas is a well-established system to the industry, with proven track record in hundreds of applications. Operational costs are not worth mentioning since it is maintenance-free and of rugged design.