Back to Basics with burner technology
Published: 08 July, 2011
The emphasis this year is going to be on using technology, servicing and clever tried and tested techniques to improve efficiencies and achieve these goals, according to Mike Baker, burner division director for Nu-way. Here, he looks at how to save money on energy bills, while keeping a close eye on carbon emission levels.
As companies and organisations in both the public and private sector seek to keep their costs to a minimum, those responsible for energy management are going back to basics and focusing on how they can save money, while also keeping carbon emissions down.
There has been a great deal of research and development in burner design and manufacture in recent years and while modern equipment doesn’t look dramatically different from older models, the operational parameters of new products inevitably deliver much higher performance and improved energy efficiency.
The big push from the UK government to ensure the installation of energy efficient equipment continues, which in turn will enable us to meet our emissions targets and some of the initiatives available include interest free loans from the Carbon Trust. But in the current climate, probably the most important consideration for those responsible for energy and involved in product selection, is to seek high specification burners that will deliver the required cost savings
In recent years, low NOx burners have become an important contributor to helping achieve these aims. Leading manufacturers have dedicated time and investment into their development and most are now offering low NOx as a standard burner feature.
Another key technique is to use modulating controls rather than on-off or high-low, this way the number of times the burner has to start up will go a long way to keeping emissions down. Improved demand matching can also be achieved by using modulating controls, and this ensures the heat output of the burner matches the levels of hot water required for the application. Use of electronic burner programmers will deliver even more precise modulating control of the air and fuel rates, also improving upon the repeatability of the air fuel ratio. The result will be reduced air levels and flue losses and increased operational efficiency.
When using burners for a large industrial or commercial application, electronic burner programmers can enable oxygen trim control. By continuously monitoring any excess air levels and with clever usage of the data provided, the air fuel ratio can be automatically adjusted to achieve optimum combustion. Where oil burners are being used, spill back valves can be used to provide accurate modulation.
In the busy day to day activity of running a manufacturing facility or production line, the subject of maintenance can easily be overlooked, but it is vital to ensure regular servicing and checks are carried out to preserve efficient and reliable operation. In addition, making sure that any faults are found and identified quickly will enable any remedial action to be taken as fast as possible. Use of electronic burner programmers can provide a complete fault history and these diagnostics allow the service engineer to carry out repairs speedily so that any potential down-time periods will be kept to a minimum.
The latest combustion fans are more and more incorporating speed control, and this is particularly relevant when working with smaller burner products. A combination of speed control and air dampers can improve turn down and result in a reduction of electrical energy consumption. The less the burner stops and starts, the greater the operating efficiency will be.
In line with all the various technical advances that have taken place over the last few years, burner design has also been modified to keep pace to offer further performance improvement. Combustion efficiency has been increased due to advanced burner head design that improves the fuel and air mixing at low fire. There are burner products on the market that permit the combustion head to be set at the time of commissioning, while enhanced designs offer automatic adjustment capabilities to position the head at both low and high fire, which also optimises combustion quality.
Looking towards the future, there is no doubt that burners will still be required to provide heat for a considerable amount of time. Research and development is going to be key to ensuring that combustion methods and technologies continue to improve and save energy and in turn reduce fuel bills for the customer. Low NOx has an important role to play in keeping emission levels down and additional advances in burner head design and air fuel mixing techniques, alongside variable adjustment heads to facilitate good air fuel mixing at all throughput levels will more than likely be the next step.
Solid state microprocessor controls will most likely become more commonly used and interrogation of operational data will result in seeking ways of improving performance. Best practice techniques such as using oxygen trim, even on the smallest burners, can make a significant difference. Together with linking to modbus or ethernet communications, this will simplify installation wiring and provide enhanced monitoring while giving preventative maintenance options for the energy or operations manager.
As the drive towards renewable equipment continues, technologies such as heat pumps will become more widespread and could reduce demand for smaller burners. In line with this, manufacturers will probably focus more on the development of larger burner products, which will mainly be used for commercial and industrial boilers. For those involved with industrial process, higher temperatures generated from fossil fuel burners will still be needed and using the latest products and techniques including recuperation for high temperature applications will ensure this continuance.
Selecting burners for industrial and commercial use can be a daunting prospect, particularly when keeping costs and emissions down is so crucial to all companies and organisations today. Burners that offer the highest efficiency possible will provide many benefits for users and manufacturers have the right knowledge and experience that can be called upon to assist with the all-important decision making process.
For further information please visit: http://www.nu-way.co.uk/