In spite of alternative energy concepts, coal-fired power plants are a technology which cannot be replaced at the moment. Installation damage and boiler downtime due to corrosion by flue gas however considerably impairs the efficiency of such combustion plants. The GM960 gas analyzer from SICK is therefore used to monitor the boiler wall.
GM960 gas analyzer
The basic problem is the sulfur and chloride content in the carbon which enters the metallic boiler walls and destroy them by corrosion. The corrosive processes themselves are highly complex. They can neither be measured directly nor simply. But they have one thing in common: They mainly take place in a reducing atmosphere, i.e., there is little or no oxygen (O2) in the fuel gas, but instead a lot of carbon monoxide (CO).The determination of reducing flue gas conditions near the boiler wall can catch potential corrosion danger in time. Diminished boiler walls can be prevented by appropriate counteractions. Thanks to the long term evaluation of the corrosive impact, service intervals can be extended and the durability of the boiler can be prolonged.
The solution is therefore: boiler wall monitoring with GM960 from SICK
For a 700-MW steam generator fired by black coal, SICK offers the adequate measuring system to extensively prevent corrosion due to fuel gas on the inner boiler wall: The boiler wall monitor GM960. The CO and O2 concentrations are permanently and reliably measured at many different points of the boiler wall. The gas concentrations are used as indicators of a potential corrosion problem. The measuring concept of the GM960 is designed to enable an examination of the flue gas atmosphere at the inner boiler wall as an entire entity. The CO and O2 values are analyzed at 40 measuring points and the corrosion-specific values CO corrosion level and CO corrosion load are calculated. In practice two sensors (CO and O2) and an electronic unit are installed at each of these measuring points. All measuring points are connected via data bus to an industrial PC controlling the whole system, analyzing the data and generating alarm signals in case an acute corrosion danger is recognized. Thus counteractions can immediately be taken.
Recognize and prevent corrosion in time
The GM960 analyzes the flue gas simultaneously at all measuring points. From the measured CO and O2 concentrations, the CO corrosion level and CO corrosion load are determined for each measuring point. The CO corrosion level is a trend measurement for assessing the present risk of corrosion to the boiler wall. The CO corrosion load indicates the level of long-term corrosive impact the boiler wall was exposed to near the measuring point. The boiler wall monitor provides permanent information about the potential risk of corrosion to the boiler wall. The GM960 supports the ideal adjustment of the burners and combustion air. Evaluation of the measurement data can facilitate efficient maintenance and revision plans. All this reduces operating costs and increases operational safety. All data is evaluated, saved and graphically depicted in the master unit. Linking the master unit to the companys own data network provides an overview of the most important measurement data on each workplace PC in the power plant.
- Product information: GM960 gas analyzer
- More solutions: Power Plant
