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Papers by Robin Brooks
Journal of Hazardous Materials, Nov 1, 2004
A new mathematical treatment of alarms that considers them as multi-variable interactions between... more A new mathematical treatment of alarms that considers them as multi-variable interactions between process variables has provided the first-ever method to calculate values for alarm limits. This has resulted in substantial reductions in false alarms and hence in alarm annunciation rates in field trials. It has also unified alarm management, process control and product quality control into a single mathematical framework so that operations improvement and hence economic benefits are obtained at the same time as increased process safety. Additionally, an algorithm has been developed that advises what changes should be made to Manipulable process variables to clear an alarm. The multi-variable Best Operating Zone at the heart of the method is derived from existing historical data using equation-free methods. It does not require a first-principles process model or an expensive series of process identification experiments. Integral with the method is a new format Process Operator Display that uses only existing variables to fully describe the multi-variable operating space. This combination of features makes it an affordable and maintainable solution for small plants and single items of equipment as well as for the largest plants. In many cases, it also provides the justification for the investments about to be made or already made in process historian systems. Field Trials have been and are being conducted at IneosChlor and Mallinckrodt Chemicals, both in the UK, of the new geometric process control (GPC) method for improving the quality of both process operations and product by providing Process Alarms and Alerts of much high quality than ever before. The paper describes the methods used, including a simple visual method for Alarm Rationalisation that quickly delivers large sets of Consistent Alarm Limits, and the extension to full Alert Management with highlights from the Field Trials to indicate the overall effectiveness of the method in practice.
All Days, Feb 25, 2008
The control of a drill in realtime is demanding on the skills and experience of the drill operato... more The control of a drill in realtime is demanding on the skills and experience of the drill operator and is variable across operating shifts because different operators have different levels of skill and experience. A mathematical model that could be shared by operators would eliminate this variability but few, if any, exist because of the mathematical difficulty and considerable expense of creating such a model in the first place and then of updating it as geology and hole depth and the type of drilling changes. This paper describes and demonstrates a radically different approach and a solution to the problem by modelling the operating envelope of the drill operation as a multi-dimensional solid object so that the operating problem becomes a geometric problem of operating always as an interior point of the envelope. The beauty of this approach is that the model developers and maintainers do not need any mathematical knowledge or the ability to describe problems with algebraic or differential equations. The method is able to create models of high dimensionality using the original process variables only so is easily understood and accepted. It is well-placed for realtime exploitation of the increasing number of down-hole measurements. The geometric basis of the model makes the operating advice that it generates intrinsically safe. A realtime operator guidance model will be developed and shown during the presentation to show the concepts, mechanics and possibilities of the method. The method is part of the overall technology known as Geometric Process Control (GPC) which is becoming well-established in downstream process industries and has already achieved success in problem-solving and offshore process improvement applications with several major North Sea operators. It has won awards for Innovation from EPSC, IChemE, IET and the CIA (Chemical Industries Association).
All Days, 2008
The control of a drill in realtime is demanding on the skills and experience of the drill operato... more The control of a drill in realtime is demanding on the skills and experience of the drill operator and is variable across operating shifts because different operators have different levels of skill and experience. A mathematical model that could be shared by operators would eliminate this variability but few, if any, exist because of the mathematical difficulty and considerable expense of creating such a model in the first place and then of updating it as geology and hole depth and the type of drilling changes. This paper describes and demonstrates a radically different approach and a solution to the problem by modelling the operating envelope of the drill operation as a multi-dimensional solid object so that the operating problem becomes a geometric problem of operating always as an interior point of the envelope. The beauty of this approach is that the model developers and maintainers do not need any mathematical knowledge or the ability to describe problems with algebraic or diff...
Journal of Hazardous Materials, 2004
A new mathematical treatment of alarms that considers them as multi-variable interactions between... more A new mathematical treatment of alarms that considers them as multi-variable interactions between process variables has provided the first-ever method to calculate values for alarm limits. This has resulted in substantial reductions in false alarms and hence in alarm annunciation rates in field trials. It has also unified alarm management, process control and product quality control into a single mathematical framework so that operations improvement and hence economic benefits are obtained at the same time as increased process safety. Additionally, an algorithm has been developed that advises what changes should be made to Manipulable process variables to clear an alarm.
Conference Presentations by Robin Brooks
IChemE Symposium Series Hazards 23, 2012
Operator Alarms should be the first line of defence in every plant but all too often are more of ... more Operator Alarms should be the first line of defence in every plant but all too often are more of a nuisance than an aid to the operator. This exposes safety alarms to more process excursions with the consequent increase in probability of a Failure upon Demand detracting from the plants overall safety capability. Poor operator alarms also contribute to poor process economics. The situation has arisen because there has never been a fundamental understanding of how alarm limits relate to process control and to process operating objectives. We have identified that the Operating Envelope of a batch or continuous process is the missing factor that unites all three topics. Operator Alarms are interrelated by positioning them on the boundary of an operating envelope which is today approximated by an alarm window or hypercube. Understanding and using the geometric relationship between an operating envelope and its approximating hypercube eliminates many false alarms. This substantially improves the credibility of the alarm system to the operator and allows earlier annunciation with more time for the operator to respond. The new alarms give the operator earlier and positive warning of deviation from whatever combination of business, environmental and process performance objectives are the operating windows chosen objective thus contributing to the economic performance of the plant and so earning the alarm system a share of the business case for further investment. Process control has, for the first time, a well-defined boundary within which to operate so that it can deliver business objectives not measurable in real-time. The method complies fully with the project methodology and the achievement of EEMUA 191 and ISA SP18 ergonomic objectives and in addition is interactive and predictive so that alarm system performance can be predicted for any set of alarm limits being considered to provide immediate, interactive feedback during the alarm review process. This makes alarm reviews fact-based instead of opinion-based and so saves considerable time in the review process for all involved. Alarm Floods are investigated and recognised as the process moving into a different operating envelope. This suggests separate sets of alarm limits for normal and flood modes of operation. Some floods can be separated into a disturbance period and a prolonged process settling period caused by interacting circulation or recycle loops such as in an ethylene process and may be the bulk of what is remembered as 'the alarm flood'.
IChemE Symposium Series No. 156 Hazards 22, 2011
Quantifying the economic value of an Alarm System, or even the value of rationalising it, has rar... more Quantifying the economic value of an Alarm System, or even the value of rationalising it, has rarely been attempted. Alarm Systems are in that category of things imposed upon a plant either by legislation or by the fear of litigation and backed by bodies such as OSHA and HSE or, in the case of operator alarms, that come over-enthusiastically configured as part of the DCS along with the built-in need for a later rationalisation project to make them usable. Few, if any, plants actually know the value, as opposed to the cost, of their alarm systems hence they can not justify and do not see a need to initiate projects involving additional expenditure on, for instance, alarm rationalisation or ongoing continuous improvement of the alarm systems. The root cause has been lack of a fundamental understanding of alarms exemplified by the fact that there has never previously been a general method to find values at which to set the alarm limits, although this is where many or most of the problems of alarm systems begin and therefore could end. We show that alarms should be related to the Operating Envelope required to achieve the plant's business objectives and so provide a general and easily implemented method for finding alarm limit values. Operating Envelopes have been poorly understood, although the term is in common use, and no method for finding or using them has existed. We show how they are easily found for various business and process objectives and how they are related to alarm limits. The example used throughout this paper is a hydro-desulphurisation (HDS) unit having three distinct Modes of operation. In this paper we show that Alarm Limits and Operating Limits are linked by the Operating Envelope. They should in principle be the same, thus allowing Alarm Limits and their rationalisation to benefit from the well-developed economic understanding already in existence for Operating Limits. That they are not the same today is probably because it was not previously possible to see, compare and work with Operating Envelopes.
Journal of Hazardous Materials, Nov 1, 2004
A new mathematical treatment of alarms that considers them as multi-variable interactions between... more A new mathematical treatment of alarms that considers them as multi-variable interactions between process variables has provided the first-ever method to calculate values for alarm limits. This has resulted in substantial reductions in false alarms and hence in alarm annunciation rates in field trials. It has also unified alarm management, process control and product quality control into a single mathematical framework so that operations improvement and hence economic benefits are obtained at the same time as increased process safety. Additionally, an algorithm has been developed that advises what changes should be made to Manipulable process variables to clear an alarm. The multi-variable Best Operating Zone at the heart of the method is derived from existing historical data using equation-free methods. It does not require a first-principles process model or an expensive series of process identification experiments. Integral with the method is a new format Process Operator Display that uses only existing variables to fully describe the multi-variable operating space. This combination of features makes it an affordable and maintainable solution for small plants and single items of equipment as well as for the largest plants. In many cases, it also provides the justification for the investments about to be made or already made in process historian systems. Field Trials have been and are being conducted at IneosChlor and Mallinckrodt Chemicals, both in the UK, of the new geometric process control (GPC) method for improving the quality of both process operations and product by providing Process Alarms and Alerts of much high quality than ever before. The paper describes the methods used, including a simple visual method for Alarm Rationalisation that quickly delivers large sets of Consistent Alarm Limits, and the extension to full Alert Management with highlights from the Field Trials to indicate the overall effectiveness of the method in practice.
All Days, Feb 25, 2008
The control of a drill in realtime is demanding on the skills and experience of the drill operato... more The control of a drill in realtime is demanding on the skills and experience of the drill operator and is variable across operating shifts because different operators have different levels of skill and experience. A mathematical model that could be shared by operators would eliminate this variability but few, if any, exist because of the mathematical difficulty and considerable expense of creating such a model in the first place and then of updating it as geology and hole depth and the type of drilling changes. This paper describes and demonstrates a radically different approach and a solution to the problem by modelling the operating envelope of the drill operation as a multi-dimensional solid object so that the operating problem becomes a geometric problem of operating always as an interior point of the envelope. The beauty of this approach is that the model developers and maintainers do not need any mathematical knowledge or the ability to describe problems with algebraic or differential equations. The method is able to create models of high dimensionality using the original process variables only so is easily understood and accepted. It is well-placed for realtime exploitation of the increasing number of down-hole measurements. The geometric basis of the model makes the operating advice that it generates intrinsically safe. A realtime operator guidance model will be developed and shown during the presentation to show the concepts, mechanics and possibilities of the method. The method is part of the overall technology known as Geometric Process Control (GPC) which is becoming well-established in downstream process industries and has already achieved success in problem-solving and offshore process improvement applications with several major North Sea operators. It has won awards for Innovation from EPSC, IChemE, IET and the CIA (Chemical Industries Association).
All Days, 2008
The control of a drill in realtime is demanding on the skills and experience of the drill operato... more The control of a drill in realtime is demanding on the skills and experience of the drill operator and is variable across operating shifts because different operators have different levels of skill and experience. A mathematical model that could be shared by operators would eliminate this variability but few, if any, exist because of the mathematical difficulty and considerable expense of creating such a model in the first place and then of updating it as geology and hole depth and the type of drilling changes. This paper describes and demonstrates a radically different approach and a solution to the problem by modelling the operating envelope of the drill operation as a multi-dimensional solid object so that the operating problem becomes a geometric problem of operating always as an interior point of the envelope. The beauty of this approach is that the model developers and maintainers do not need any mathematical knowledge or the ability to describe problems with algebraic or diff...
Journal of Hazardous Materials, 2004
A new mathematical treatment of alarms that considers them as multi-variable interactions between... more A new mathematical treatment of alarms that considers them as multi-variable interactions between process variables has provided the first-ever method to calculate values for alarm limits. This has resulted in substantial reductions in false alarms and hence in alarm annunciation rates in field trials. It has also unified alarm management, process control and product quality control into a single mathematical framework so that operations improvement and hence economic benefits are obtained at the same time as increased process safety. Additionally, an algorithm has been developed that advises what changes should be made to Manipulable process variables to clear an alarm.
IChemE Symposium Series Hazards 23, 2012
Operator Alarms should be the first line of defence in every plant but all too often are more of ... more Operator Alarms should be the first line of defence in every plant but all too often are more of a nuisance than an aid to the operator. This exposes safety alarms to more process excursions with the consequent increase in probability of a Failure upon Demand detracting from the plants overall safety capability. Poor operator alarms also contribute to poor process economics. The situation has arisen because there has never been a fundamental understanding of how alarm limits relate to process control and to process operating objectives. We have identified that the Operating Envelope of a batch or continuous process is the missing factor that unites all three topics. Operator Alarms are interrelated by positioning them on the boundary of an operating envelope which is today approximated by an alarm window or hypercube. Understanding and using the geometric relationship between an operating envelope and its approximating hypercube eliminates many false alarms. This substantially improves the credibility of the alarm system to the operator and allows earlier annunciation with more time for the operator to respond. The new alarms give the operator earlier and positive warning of deviation from whatever combination of business, environmental and process performance objectives are the operating windows chosen objective thus contributing to the economic performance of the plant and so earning the alarm system a share of the business case for further investment. Process control has, for the first time, a well-defined boundary within which to operate so that it can deliver business objectives not measurable in real-time. The method complies fully with the project methodology and the achievement of EEMUA 191 and ISA SP18 ergonomic objectives and in addition is interactive and predictive so that alarm system performance can be predicted for any set of alarm limits being considered to provide immediate, interactive feedback during the alarm review process. This makes alarm reviews fact-based instead of opinion-based and so saves considerable time in the review process for all involved. Alarm Floods are investigated and recognised as the process moving into a different operating envelope. This suggests separate sets of alarm limits for normal and flood modes of operation. Some floods can be separated into a disturbance period and a prolonged process settling period caused by interacting circulation or recycle loops such as in an ethylene process and may be the bulk of what is remembered as 'the alarm flood'.
IChemE Symposium Series No. 156 Hazards 22, 2011
Quantifying the economic value of an Alarm System, or even the value of rationalising it, has rar... more Quantifying the economic value of an Alarm System, or even the value of rationalising it, has rarely been attempted. Alarm Systems are in that category of things imposed upon a plant either by legislation or by the fear of litigation and backed by bodies such as OSHA and HSE or, in the case of operator alarms, that come over-enthusiastically configured as part of the DCS along with the built-in need for a later rationalisation project to make them usable. Few, if any, plants actually know the value, as opposed to the cost, of their alarm systems hence they can not justify and do not see a need to initiate projects involving additional expenditure on, for instance, alarm rationalisation or ongoing continuous improvement of the alarm systems. The root cause has been lack of a fundamental understanding of alarms exemplified by the fact that there has never previously been a general method to find values at which to set the alarm limits, although this is where many or most of the problems of alarm systems begin and therefore could end. We show that alarms should be related to the Operating Envelope required to achieve the plant's business objectives and so provide a general and easily implemented method for finding alarm limit values. Operating Envelopes have been poorly understood, although the term is in common use, and no method for finding or using them has existed. We show how they are easily found for various business and process objectives and how they are related to alarm limits. The example used throughout this paper is a hydro-desulphurisation (HDS) unit having three distinct Modes of operation. In this paper we show that Alarm Limits and Operating Limits are linked by the Operating Envelope. They should in principle be the same, thus allowing Alarm Limits and their rationalisation to benefit from the well-developed economic understanding already in existence for Operating Limits. That they are not the same today is probably because it was not previously possible to see, compare and work with Operating Envelopes.