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NEWS

Significantly lower emission levels with NOx abatement

ince implementing one of the first with the legal requirements. B&W, a U.S.-based technology firm founded in 1867, has more
nitrogen oxide (NOx) abatement than 50 years of experience in installing low NOx combustion systems for both new and retrofit
Sprojects in the country in 2019, boiler applications around the world.”
Babcock International has completed a Gerber says that B&W’s DRB-XCL® low NOx burners were selected to help meet the new
further three boiler installations at a large emissions limits. One of the main advantages of the DRB-XCL burner is that the internals of
industrial petrochemical plant, reaching the burner are customisable and burner performance can be optimised in situ by adjusting
emission levels of almost 40% lower than components. This enabled priority to initially be given to stable operation, and upon site
the legal requirements. testing, boiler system settings and burner internals could be adjusted incrementally until the
Nitrogen oxides are harmful gases optimum balance between stability and minimum NOx was achieved.
that form when fuel is burned at high “During the final performance test of the installation in the fourth iteration, NOx emissions
temperatures emitted through combustion were reduced by more than 40 percent of the targeted emissions level,” says Gerber. He
of fossil fuels, which remain the primary explains that the system operators are a vital link in the performance of the boilers, as they
source of South Africa’s power. To improve can monitor and adjust the settings to optimise the boiler’s performance. Babcock provided
air quality, nations around the world have training for operators about how the technology works and what is required from operators for
committed to lower NOx emissions through the system to be optimised.
legislation that determines acceptable Reflecting on the performance and lessons learnt since the first installation, Matimba
levels of NOx in the atmosphere. In Mangotlo, Project Engineer for Babcock, says that the hardware has proven to be extremely
South Africa, the National Environmental reliable, which is critical for this type of plant.
Management: Air Quality Act calls for “Furthermore, there has been continuous improvement in the way we design, project
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maximum NOx levels of 750 mg/Nm for manage, and stakeholder manage each installation. We have also introduced industrial
solid fuel combustion installations with a relations to involve the local community so that each outage is managed without incident.”
thermal rating of more than 50 MW. He explains that the installations must take place within planned outages, so time is of the
Babcock’s first NOx abatement essence. “We have refined our project delivery for every boiler that is completed and have
installation, which achieved levels of demonstrated that the project can be implemented successfully over 15 months in parallel
651 mg/Nm , received the South African with other boilers, which is an improvement of 17 months compared to the initial installation,”
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National Energy Association (SANEA) says Mangotlo.
Energy Project Award in 2019. Three “Whilst B&W remains a key partner and continues to provide support to the local Babcock
additional iterations have been completed team throughout each unit’s engineering, installation and commissioning phases, we are proud
since the first installation, with the most to have local expertise to address local challenges,” says Gerber.
recent recording the greatest success “As South Africa’s leading steam generation service provider, Babcock has all the
where performance tests delivered post- engineering disciplines in-house to successfully deliver a project of this scope, from process,
abatement NOx emissions of 469 mg/ thermal and control instrumentation to mechanical and piping engineering capabilities –
Nm – making this among the lowest NOx ensuring support throughout the project life cycle.
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emissions for a pulverised coal (PC)-fired “We are proud to be involved in a project of this nature that makes a significant
boiler installation in South Africa. improvement to air quality in South Africa,” concludes Gerber.
Juan Gerber, Process Engineering
Manager at Babcock, explains that PC-fired Contact Juan Gerber, Babcock, juan.gerber@babcock.co.za
boilers are generally larger utility-type
boilers that generate steam, which in
turn generates power. To regulate NOx
emissions, new power plants are fitted
with low NOx burners, while older PC-fired
boilers would require to be retrofitted to
comply with legislation by 2025 in order to
continue operating.
“These boilers generate power for
the client’s own use and for resale, so in
the event the boilers need to be switched
off, the consequences are immense,” says
Gerber. “We worked with Babcock & Wilcox
(B&W) to provide a solution to ensure
the client’s petrochemical plant, which
comprises 12 boilers in total, is compliant

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