Providing solutions to complex Burner Management System (BMS) applications requires a combination of process knowledge, regulatory awareness, robust components, and an intuitive interface all applied with industry experience to ensure that life, equipment, and revenue are well-protected.
A BMS is truly the last line of defense in preventing the catastrophic failure of a boiler, fired heater or other industrial heating systems involving the combustion of a fossil fuel. Safety is always the number one priority.
Industrial Energy processes involve large equipment and machinery, combustion, some hazardous materials, and other potentially dangerous aspects. Proper safety practices and procedures must always be in place and used. The end user must therefore be confident that the BMS supplier has a firm understanding in several key areas.
It is important that experienced individuals who are intimately familiar with the particularities of the combustion processes considered be engaged as early as possible in the project. Deep process knowledge and an understanding of the particular caveats of a customer’s system go far to ensure that details are identified and common pitfalls are avoided.
Familiarity with the applicable BMS and flame safety codes is essential so that BMS systems perform satisfactorily. Prescriptive and regulatory codes such and NFPA 85, 86, and 87; API 556; ISA-TR84.00.05; AS 3814 describe the jurisdiction under which the BMS system must be designed. These codes also provide clear direction on the required physical separation between the BMS and the regulatory and advanced control systems. This is especially important when dealing with retrofitting of older units. It is important to realize that a simple like for like replacement of a BMS system is generally not acceptable.
When upgrading to a modern BMS, the latest codes and requirements must be followed. Some of these new requirements may not have been in place at the time the legacy BMS system was installed.
BMS functionality should include the following:
Purge Interlocks and Monitoring
Monitoring and purging of the unit to ensure that it is adequately purged of accumulated fuel before a burner light off is attempted.
Fuel Header/Burner Starting and Tripping Logic
Control of fuel header and burner starting sequences to ensure safe firing practices, the system will trip the burner and/or fuel header when conditions occur that might lead to an accumulation of unburned fuel in the furnace.
Alarms and System Diagnostics
An extensive set of alarm and system diagnostic messages for operations personnel to enhance operator effectiveness, bring situations of potential combustion instability to the operator’s attention, and improve process maintenance by providing quick identification and isolation of problems such as:
• First Out Cause of Trip
• Missing Interlocks and Permissives
• System Hardware Fault Identification
• Field Device Failure
Improved BMS functionality
BMS implementations have typically been done simply to comply with code and have delivered a minimum of functionality. In practice, this has often left site operations “in the dark” as to the status of the BMS sequence or any field device issues. If an interlock was preventing light-off or if the combustion process tripped, little or no information was available about the cause of the problem.
BMS Solutions should provide extensive diagnostic information for operations and maintenance such that:
• Burner light-off is simplified and accomplished more quickly
• Causes of process trips are identified more quickly and downtime is reduced
• Repeat causes of combustion problems are pinpointed so that downtime can be lessened