RJM CleanAir Burner™ install to cut air pollution

Key challenges

RJM was tasked with providing new Ultra-Low NOx CleanAir Burners™ to meet a NOx threshold of 30mg/Nm³ or less. These were fitted to six new Taishan 70MWth single burner boilers (one per unit) for Huayuan, at one of its district heating plants in Beijing.

RJM Solution

Using an IFGR system as the primary NOx reduction technology, RJM’s design took flue gases at 220°C on full load and transported them to the FD inlet via an IFGR flow, using the FD suction fan only, with no requirement for air pre-heating. In addition, CFD modelling was used to design a bespoke mixing box to provide homogeneous mixing of FGR and air at the FD fan inlet ductwork. RJM also designed a new windbox – needed for the larger burner – but in such a way that it would fit within a standard intermodal container, for ease of transportation by rail from the UK.

One of the six RJM HY-70 CleanAir Burners™ destined for a district heating plant in Beijing

Results

NOx levels achieved were <30mg/Nm³ at 3.5% O₂ with up to 30% FGR and CO emissions of <10mg/Nm³ at 3.5% O₂ across the load range with stable flames.

RJM’s CFD of the new windbox confirmed excellent velocity distribution.