Reducera stopptiden för en lutanalysator : Kan detta göras med ett användarvänligt gränssnitt?

Sammanfattning: The Smurfit Kappa Piteå is Europe's largest paper mill for Kraftliner. [1] The factory contains of both a sulphate mill and a paper mill including two paper machines. In a sulphate mill, pulp is produced by boiling wood chips with liquor that contains active chemicals such as Na2S and NaOH. There is a cost saving in chemical recycling instead of replacing used chemicals with new ones. In order for boiling pulp and have the process of recycling of chemicals to work optimally, the various liquids must maintain certain values and concentrations. It takes a lot of time and resources when the operators have to do it manually, and therefore the process owner has invested in a process analyzer that is physically connected to the pipes where the chemicals pass to automatically take out samples and analyze them. However, the analyzer has very big problems with crystallization of transportation pipes, valves that get stuck, and the only unit that provides information about the problems is a HMI-display located next to the factory's soda boiler. This place next to the soda boiler is an unpleasant area to stay at. That is one of the reasons that it often takes a long time from the analyzer encounters a problem until someone discovers the problem and contacts the accurate service department to fix the problem. The availability of the analyzer thus needs to be developed. The analyzer had its own PLC with control signals for valves and sensors. Those signals were picked out and sent through a PROFIbus DP to the operators ordinary control system ABB 800Xa. Also, a process image of the analyzer was designed and a number of functions for detecting and reporting problems were implemented. Each valve and sensor received its own faceplate with associated alarms. Now the operators could, with this user-friendly system, more quickly detect problems and address them to the right maintenance department. By interviewing the operators who work with the analyzer, it was made possible to measure the use of creating a new process image as a tool for troubleshooting. Many operators say in the interviews that they feel that the new process image makes them more aware of operational malfunctions of the analyzer that require action. However, some of the mechanical weaknesses in the design that cause these problems still remains, and must be fixed.