Reliable pH measurement in pulp production can be problematic to maintain, with solid content in pulp and sulphides used as cooking chemicals quickly clogging the diaphragm, and poisoning the reference system on conventional pH sensors. Regular cleaning can extend the lifetime of sensors, but is time consuming and costly for operators.
Seshasayee Paper and Boards Limited (SPB) has operated an integrated pulp, paper and paper board mill in Tamilnadu, India, since 1960. METTLER TOLEDO’s solution to SPB’s pH sensor problem was the implementation of a measurement system based around our InPro® 4801i sensor. This probe is designed for high performance and long lifetime in harsh environments, such as pulp production and offers extended sensor lifetime due to its long diffusion path and PTFE-coated diaphragm that reduces clogging.
For sensor monitoring and control, an M300 transmitter was selected to combine convenience with ease of use, fast installation and user-friendly configuration in any convenient location. To simplify cleaning, an InTrac® 777 retractable housing containing a flushing chamber for easy and efficient sensor rinsing, without process interruption.
Since installing the system, SPB mill operators can now use their PLC to operate the pneumatic InTrac housing, quickly and thoroughly rinsing process material from sensors. Due to the long sensor lifetime and greater reliability, mill managers calculate that operating costs for the new system are half of what they were prior to use, and are planning to convert all pH measurement points at the facility to METTLER TOLEDO sensors.
For more information contact www.mt.com/gb/en/home/library/case-studies/process-analytics/ph-measurement-in-pulp.html or call Call 0116 234 5095; or Email [email protected]