K-Patents will present the latest innovations in in-line concentration measurement technology at the PulPaper 2007 exhibition at the Helsinki Fair Center in June 5-7th, 2007.
The new K-Patents SAFE-DRIVETM Process Refractometer PR-23-SD is a retractable refractometer for measuring black liquor dry solids and green liquor density or TTA in kraft chemical recovery process. The K-Patents SAFE-DRIVETM design allows for safe and easy insertion and retraction of the sensor under full operating pressure without having to shut down the process.
The new K-Patents Digital Divert Control System DD-23 complies strictly with all recommendations of the Black Liquor Recovery Boiler Advisory Committee (BLRBAC). The DD-23 system includes two SAFE-DRIVETM Process refractometer sensors in the main black liquor line, and an integrated panel with two Indicating transmitters and a Divert control unit Each refractometer is a completely independent measurement system. Each system sends a separate output signal, which can be used by a control system or a DCS.
Feeding low concentrations of black liquor solids to a kraft chemical recovery boiler burner can cause a steam explosion. A digital divert control system is required to ensure safe operation.
BLRBAC recommends standards for safe firing of black liquor and suggests using an automatic black liquor divert control system to ensure that weak liquor is not fed into the boiler. BLRBAC requires that if the black liquor concentration falls below 58%, the system shall give an audible alarm signal, and go to a diversion function to direct the black liquor flow to bypass the boiler. A concentration value of 60% shall give an audible alarm to notify the users about the low concentration. Furthermore, the control unit shall check that the difference between the signals of the two individual refractometers does not exceed 2%.
These close tolerances require digital circuitry which eliminates drift.
K-Patents provides process refractometers for measuring dry solids, liquid density, concentration and TTA (Total Titratable Alkali) in kraft chemical pulp and paper mills.
Our key expertise over the last 25 years has been in optimizing energy-intensive operations: reducing consumption of pulp chemicals and usage of water in washing, reducing steam usage and maximizing the capacity of evaporators, and controlling green liquor in causticizing. Also, recovery boiler safety can be increased by using K-Patents instrumentation.