Riello burners help drive efficiency for Telereal Trillium
Following a detailed technical appraisal and competitive tender exercise, Riello burners were selected as the best match for the refurbished boilers at a high profile government site in Swansea, managed on behalf of Telereal Trillium by Arthur Portelli of Oakbury Building Services Consultants.
The 3 x 2.5 MW burners at the site were installed in 1982 to meet a site demand of around 5MW with N+1 resilience so that heat loads could be met with one boiler offline for maintenance or repair. Because of the age of the burners, and efficiency issues being experienced, Telereal Trillium carried out a technical review to assess condition and future operational life of the boiler plant.
Having considered several options, a comprehensive refurbishment of the three 2.5MW high temperature dual fuel hot water boilers was identified as the best option, bringing them up to the standard of any new boiler on the market. A further benefit of refurbishment was reduced disruption, taking advantage of the N+1 configuration.
The refurbishment by Steam Plant Hire (Halesowen) included installation of new high efficiency insulation, refractory, control wiring, casings, gas and oil pipe systems and replacement of the obsolete burners. A driving factor for the project was to improve overall efficiency, so selecting the correct burner system was critical to achieving the required combustion efficiency, along with improved turndown and low emissions (including NOx).
After reviewing several burners available on the market, two burner manufacturers were invited to tender for the programme and Riello undertook a full burner matching process, which included a site visit and assessment of the existing installation. Following a presentation to Telereal Trillium, RLS300 EV O2 BLU low NOx dual-fuel burners were identified as offering the best option.
“I am grateful to the Riello team for their efforts during the replacement of the 3 x 2.5 MW burners,” commented Arthur Portelli, Director of Oakbury Building Services Consultants.
“This was a particularly challenging project for a whole number of reasons and I was impressed with the manner that the team handled all the problems we encountered at the design, tender and project stage. The support from the Riello sales and technical teams has been first class, only equalled by the burners that have lived up to all expectations,” he added.
In addition to delivering the required performance, the compact ‘monobloc’ design of the RLS300 EV O2 BLU enabled better use of available space in the plant room. This was because the previous burners were of a ‘dualbloc’ design with additional separate air fans and motors and separate control panels – all of which were no longer required.
The burners were supplied with a Siemens LMV52 burner management system, which will work in conjunction with Riello’s electronic CAM technology to enhance combustion efficiency through accurate control of excess oxygen levels. Further efficiencies will be achieved using oxygen trim control and variable speed control of the main fan motor. The latter has been shown to reduce electrical consumption by up to 35% compared to fixed speed motors, as well as reducing noise levels.
The RLS300 EV O2 BLU also incorporates Riello’s low NOx combustion head design, which guarantees excellent mixing of fuel and oxygen at all firing rates. In parallel, a system for internal recirculation of combustion gases (flue gas recirculation) back into the flame contributes to low NOx levels of <80mg/kWh, compliant with EN676 (Gas), Level 3.
Boiler ‘efficiency kits’ were selected by Telereal Trillium as part of the burner system which, when connected to the LMV52 burner management system, allows for the boiler efficiency to be monitored in ‘real time’. This can be uploaded via a suitable Modbus system to allow the BMS to display and monitor the current boiler efficiency.
Riello worked closely with the project team throughout the refurbishment to ensure timely delivery of burners and ancillary equipment in line with the programme of works.
Further information: www.rielloburners.co.uk