Recovery-boiler leak detection using a waterside chemical-mass-balance method

Water leaks in a black-liquor recovery boiler can cause explosions if the water reaches the molten smelt bed of the boiler. This paper describes a system that detects boiler leaks using a waterside chemical mass balance. A microprocessor-based chemical-feed system meters chemicals to match the losses that occur via blowdown, and boiler-water chemistry is monitored continuously. A water loss is indicated when the expected and measured chemical concentrations diverge. Field experience with this system is presented. Application : a new system for automatic detection of recovery-boiler leaks.