The PT Bintan Alumina Indonesia power plant was built to support a 2000kt/a alumina project and included 5×40000Nm³/h circulating fluidized bed coal gasification boilers. When the alumina project reached full production capacity, fly ash output reached approximately 240–260 tons per day, with a calorific value of about 5100 Kcal/kg.

During the initial 1000kt/a alumina phase, coal gasification fly ash could only be directly burned. Each boiler consumed about 7–10 tons per day (two boilers total), while brick factories still needed to manually mix and landfill 50–60 tons per day. The original design used intermittent ash feeding every 5 minutes without injection pipes, causing multiple daily ash blockages that were time-consuming to clean and affected combustion efficiency.

During dry ash transportation, serious dust pollution affected the surrounding environment. After ash co-firing, black ash accumulated on the boiler body, manholes, and ash conveying pipeline valves, often causing spontaneous combustion after heating. During landfill operations using air compressor pumping methods, the fine and highly fluid ash generated severe dust and floating ash on water surfaces. After rainfall, the lightweight ash was frequently washed onto the ground, negatively affecting the local community.

To solve these issues and achieve full combustion of coal gasification fly ash, the power plant upgraded and modified the original fly ash co-firing system, ultimately achieving complete utilization of coal fly ash.

The modifications included upgrades to the pressure vessel pressurization system, auxiliary blowing conveying system, nitrogen and compressed air systems, and ash conveying logic. Compared with the previous system, the upgraded power plant achieved continuous zero discharge and complete combustion of coal fly ash. The success of the modification generated significant economic benefits, improved environmental protection performance, and gained positive social recognition locally.