Development of on-line evaporator performance monitoring systems at Mulgrave mill

In order to take full advantage of the cleaning system installed at Mulgrave Mill in 1995, a system to measure evaporator performance on-line has been developed. This system involves monitoring a number of points around the evaporator set including vapour temperatures, and some juice and condensate flows. The information is transmitted to a computer which calculates evaporator performance figures for each effect, as well as recording and trending figures and producing reports. It is planned to use the information for planning and scheduling evaporator cleaning operations, with these taking place only on those effects that are significantly fouled. In this way the time required for cleaning procedures would be reduced, and the flexibility of maintenance scheduling increased. Evaporator cleaning costs would also be reduced, as would the quantity of used cleaning materials requiring disposal. The system may also be useful in examining other aspects of evaporator performance and operation.