Stable, effective acid removal indicators are being achieved at Zhanjiang Steel thanks to a new, CISDI-developed blast furnace gas system for the blast furnace 2 sprinkling tower.

The 5,050 cubic metre furnace is five years old and the new BFG de-acidifying system was built during its short, four-monthly repair periods.

The rebuild increases the PH value of condensate water from 3.4 to 5.4 for the BFG’s pipeline network. The problem of acid corrosion has been eradicated, increasing plant safety.

BFG pipelines are subjected to condensate water acid corrosion when dry bag filter technology is applied to the BFG cleaning system, although plus top gas recovery turbine for power generation can create huge economic and social benefits.

The condensate water’s strong acidity - a PH value of lower than 1.7 - had been a long-term problem and affected safety during operation of the gas pipeline network, the TRT power generation unit and the hot stoves.

This problem has long been a challenge for the blast furnace ironmaking sector and in early 2020 CISDI put together a dedicated team to research and develop BFG de-acidifying technology.

The team visited Zhanjiang to investigate the deterioration problem and verify the de-acidifying effects.

Their solutions enabled production to continue uninterrupted and have been granted multiple patents through combined TRIZ, BIM and collaborated design means.

A CISDI engineer monitors BFG acidity at Baosteel Zhanjiang’s blast furnace 2