RDA Research Project
Utilize CoMate technology to improve boiler efficiency at EDF Krakow - Minimize the rate of build-up of combustion by-products on boiler heating surfaces.
In a 52 day demonstration, RDA engineers designed and tested the direct injection of CoMate Ash Modifier into a 110 MW coal/biomass fired boiler, operated by EDF; Krakow, Poland.
RDA designed and installed a CoMate feed systems to the specifications of the EDF Krakow boiler, to allow for the direct injection of CoMate Ash Modifier at 250 Kg per day, later adjusted to 325 kg to account for the high fuel mix of sunflower husks.The coal / biomass fuel mixture varied at ratios of 70/30 and 55/45.
In a facility initially designed for coal, the addition of biomass fuel resulted in operating cycles in the 45 day range with an intense build-up of slagging on heating surfaces.
In addition to fuel variations, the design of the superheater / reheater region, left these areas particularly vulnerable to erosion and strong fouling.
2. Shipment unloaded
Variations in MW: The plant runs by day at 110MW and powers down by night to 65 MW - to mitigate these additional variables, a CoMate feed rate table was established.
Variations in the coal/ biomass fuel ratio: The fuel ratios varied as well as the biomass mixture. A heavier mix of sunflower husks caused an increase in fouling. CoMate rate feeds were increased by 30% - mitigating fouling and returning the boiler to acceptable operating parameters.
Unrelated to the CoMate testing, the plant underwent a 41 hour shutdown, due to a tube leak in the economizer.
CoMate was effective in successful mitigating fouling and increasing boiler efficiency and operating cycle.
Operating cycled improved – with initial CoMate injection projections to prolong cycle to 500 days
A 29% reduction in the rise of deposits - Efficiency of deposition went from initial reads of 5.22% to 3.7% and 3.64%, respectively, when CoMate was fed into the boiler (initial measurement of 33wt% content)
Immediate stabilization of the flue gas and steam temperatures to their design points.
Fouling and ash build-up in the super heater and re-heater areas of the boiler became soft and friable.
Softer deposits on boiler tubes equates to less reliance on soot blowing and the risk of erosion to boiler tubes and shields.
Reheat steam temperatures were maintained close to design (540 C) and under pressures, largely at -0.2 and -0.4 KPA, this was due to easily removable ash on the boiler tubes.
110 MW Superheater before CoMate demonstration
RDA At Work
Hefler Forest Products
Helfer Forest Products
RDA has been working closely with the Hefler team since we first launched a CoMate demonstration in 2016.
Hefler Forest Products is located in Atlantic Canada, with sawmill operations producing quality lumber products and a 100% biomass energy plant, producing onsite renewable energy.
With two injection points located in the overfire air plenum, CoMate has made a significant reduction and softening in furnace slag deposits.The team witnessed crystalline material turn to a powdery, friable state.
To begin work RDA took the following approach:
Determine fuel, steam and electrical balance of the co-generation plant
Identify the fuel types and determine chemical composition
Identify areas in the furnace and boiler prone to clinker formation
Identify existing boiler monitoring point locations
Design and install CoMate feed system
Monitor and observe data, ash deposits and changes in boiler performance
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Closeup of freshly cut logs
Pencil demonstration of softened ash sample
Sample taken after 3 months