Savcor Corrosion and Process Monitoring
Prevention corrosion has always required also measurement of corrosion rate and process factors related to corrosion aggressivity. This has yielded Savcor a solid know-how in utilizing electrochemical measurements for the benefit of corrosion mitigation by process optimization.
In some cases, the measurable properties of process electrolyte itself are interesting and can be even used for process control. Measurement of effective alkali concentration in pulp digester is a good example.
Electrochemistry works in hot environment also. The layer of molten inorganics on the bottom of recovery boiler can be monitored in order to detect the most corroding run modes.
Measurement of entrained air in paper mill white water circulation can give significant savings in defoamer chemical costs. Savcor method is based on very accurate and repeatable ultrasonic sensors.
Corrosion Monitoring in Concrete
Reinforcement steel in concrete is naturally passivated inside the concrete, unless attacked by chlorides or carbonization. Initiation of corrosion may take years or even decades before the actual visible indication appears.
Corrosion probes can be installed in new concrete structures at or above the rebar level. They indicate the first attack of corrosion and give the asset owner a posibility to plan a preventive action. In some cases, the structure has a provision for CP installed from the beginning and it will be energized after the measurements show increased risk for corrosion.
Online Alkaline Measurement
for optimized pulping process
Control of the make-up cooking liquor, as well as initial and resulting alkali concentration, affects the uniformity of pulp produced. During the cooking process, residual alkali strength fluctuates with changes in chip composition, species, wood moisture, and the uniformity of concentration of the make-up chemicals.
Measurement of effective alkali concentration inside the digester has never been done before. The present methods require a filtered side stream which add delay and error. Savcor, together with Andritz, has utilized its long experience in electrochemical measurements inside the digesters and developed an accurate in-situ alkali measurement.
Recovery Boiler Monitoring
Environment in the furnace of recovery boiler is extremely hard for shell material, stress corrosion cracking is very common. Corrosion aggressivity depends mainly on raw material and certain process parameters such as air feed.
When the operators can see online information of the corrosion reactions, they can better adjust the process towards asset-saving conditions.
SONICA Air Content Analyzer
Sonica is an on-line air content analyser designed to measure and monitor air in paper machine stock. Sonica’s capability to operate seamlessly as a part of the process without interfering it differentiates it from the competing solutions.
Sonica collects the data accurately and it does not include any moving mechanical parts, making it highly reliable. The analyser provides higher profile control and decreased overall consumption of defoamer chemicals. The operational costs of Sonica are low and due to its ability to live as a part of the paper making process, the machine speed can be further increased.