Learning about process control

Abstract

The research site has been the Södra Cell Tofte pulp mill. The main focus in this thesis is how to learn about process control. The need for research on this theme is given implicitly in the foundation and construction of the INPRO programme. Norwegian engineering education is discipline oriented, and the INPRO programme aimed at integrating the three disciplines engineering cybernetics, chemical engineering, and organisation and work life science in a single PhD programme. One goal was to produce knowledge of modern production in chemical process plants based on socio-technical thinking.

In the introduction I outline how my research questions have been developed and the need for doing research in the field of improving process understanding in a continuous process plant.

This thesis provides answer to the three questions:

1. What are the learning systems for workers in a process plant?

2. What is the implication for learning of different socio-technical structures?

3. How can learning be further improved for workers in the process industry?

In order to answer these questions and to provide a background for why these questions are important to Tofte, I describe and analyse the case plant Södra Cell Tofte. I find it necessary to make this part rather extensive in order for the reader to understand the context under which Tofte has been developing its learning arenas or learning systems. I use a sociotechnical framework in doing this. I want to introduce and use this framework as I regard it as useful for one of my purposes with this work: Assisting the production unit at Tofte to improve learning. I go through technological improvements that have been carried out from 1980 onwards, and one major organisational change that has taken place. The downsizing and reorganisation that took place in 1992 is of importance as well as the organisational development effort named “Employeeship” that took place in 1996. I had a leave from the INPRO project for almost a year following and evaluating this particular project. The situation at Tofte in 1994 was lack of good learning systems, and after a major reorganisation in 1992 the organisation defined a need for better responsibility distribution and co-operation.

Chapters 3 and 4 present and discuss theories in order to give a broader background for the research issues in this thesis. In Chapter three I discuss features and characteristics of a continuous process plant as these have consequences on how knowledge and skills can be developed and why process understanding is a necessity. I present socio-technical system thinking (STS) as one way of regarding organisation and management of a process plant, and I further discuss why I find this approach appropriate for providing learning primarily at the shop floor level as an integrated part of daily production.

In Chapter four I argue that knowledge and skills in production are becoming increasingly important in highly automated remotely controlled process plants and develop a theory of “process understanding”. Process understanding is defined as the ability to predict what is going to happen. In order to predict what is going to happen with a system one firstly need to define the system boundaries. This system can then be regarded as a mental model. One must know and analyse input variables (know where and how to get relevant process information), and by this anticipate, like in a mental simulation, what will happen with the parameters within a defined time period. Different possible options may be mentally tested including what will happen if no corrective actions are taken. An ability to predict what is going to happen with the product, to process equipment or any other process variable, has to be developed and refined in order to operate a process plant optimally. Theories state that a variety of knowledge and skills are required and that some skills can be acquired only through years of experience. The “knowing why” within a process plant also has to be strengthen in order to develop a better process understanding, but as an addition to the experience based “knowing how”.

Models of learning regarding the demands given by the production systems in order to develop such process understanding are presented and discussed. These are conventional methods, experiential (problem based) learning, and collective learning. The experiential learning model is discussed and what may inhibit learning from experiences to take place in a plant. I have defined the concept “learning arena” and regarded each shift in a control room as a main learning arena since this is the place where theory meets practice. It is further discussed that practice will differ between shifts within same control room due to different mental models of the process. In various learning arenas, different communities-ofpractice must be joined in order to make more shared mental models with the intention to align different practices.

In Chapter five the research methods used to explore the research questions, and thus to bring forth theories about gaining better process control, are reviewed. I have been inspired by action research methods in order to answer my research questions and to contribute in a necessary change process where development and use of learning arenas have been central. I have been more or less active in these arenas and played back experiences and theories in order to further develop the arenas. Besides participations in learning arenas, methods have been interviews, observations, and written documentations.

Chapter six is the case description of two different kinds of learning systems at Tofte: Operator Training (OT) - Operator based development and execution of education/ training and Operations Workshop (OW) - Problem based learning aiming at better production practice. I have provided background for the two cases as an answer to the educational challenges Tofte had in 1996 and not least to differences in operational practice between shifts. I describe background, characteristics, and development from what I term different learning arenas where the learning about process control will take place. I have also discussed in what ways these two learning systems can be regarded as learning arenas and briefly the kind of learning that can take place in each arena. In two Operations workshops I provide more details in order to show some strengths of the method.

In Chapter seven I provide answers to the three research questions outlined in the introduction and further refined in Chapter 4.5. I analyse how different learning types such as individual, experiential, and collective are covered within different learning arenas and how OT and OW meet the requirements for good learning systems in continuous process plants. Further I analyse how tasks regarding education and training are better distributed in a shift and daytime organisation with the two learning systems, and further how learning is integrated with working and thus process operators’ knowledge and skills are better utilised. When I analyse the implication of learning of two different socio-technical structures, I also regard how managers are better enabled to become facilitators for learning. The two arenas have been well established at Tofte, but to a varying degree in the different departments. When regarding Operator training it is still too early to conclude on its impact on results in the pulp mill. However, two Operations workshops have made positive contributions and demonstrated the potential of the method. The strengths of the methods are the collective learning that place in cogenerated learning arenas. In Operator training this strengthens the master-apprentice method, and in Operations workshops it gives a shared understanding and direction for further tasks in process control. Finally, based on the analysis of the first two questions I discuss how learning for workers can be further improved.

In Chapter eighth I conclude on my theoretical contribution and arguments for further research in the actual fields. Finally, based on my findings I will recommend organisational choices on future actions. STS provides frames and directions for learning to take place within groups along the production line. It is however not the scope of the STS paradigm to provide theories of what constitutes knowledge in operations of a plant. And the STS theories are not developed in order to cover more specifically models for how learning within and across semi-autonomous units and organisational levels may take place. Thus the main contribution of this thesis is learning theories based on two different kinds of learning models as means to develop process understanding.