How to perform incinerator flue gas treatment systems?


Dalkia Waste Energy, a subsidiary of the EDF Group which specialises in environmental process engineering, contacted us in order to be able to respond to the following problem: Improvements in the performance of smoke treatment at the Villefranche-sur-Saône waste incinerator.

The farm’s mills had deficiencies in terms of granulometry at the grinding outlet as well as numerous sodium bicarbonate grinding losses, leading to over-consumption of bicarbonate for the reduction of pollutants (SO2 and HCL) in the fumes.


Proposed solutions
In order to optimise the installation, performance studies were carried out with Dalkia on the crusher. The variables measured were those of the quantities of shredded material produced in relation to the quantity of sodium bicarbonate used. Finally, granulometry tests were carried out by our Design Office technicians to determine the extent of losses in grinding the sodium bicarbonate. The part was conceptualized using our design software “SolidWorks”.

Based on the observation of the lack of performance of the grinder and the results of the tests, we recommended the replacement with a new grinder whose capacities were adjusted to be able to meet Dalkia Waste Energy’s performance requirements in an optimal way.

The main characteristics of the new shredder compared to the old one are :

  • Rationalisation of the number of shredding chambers (from 2 to 1)
  • A more precise micro-doser
  • Finer grain size applied
  • Improvements noted

The immediate improvements were seen when the new granulometry test of the mill was carried out. These tests gave satisfactory results:

  • For flow rates ranging from 20 to 480kH (the mill’s operating range to absorb the intensity of peaks) with a 7.5kW motor
  • Small flow rate: 20 microns D90 (particle size)
  • Large flow rate: 30 microns D90 (particle size)
  • < 8 mg/Nm3 for HCL
  • < 40 mg/Nm3 for SO2
  • Better agglomeration efficiency with pollutants
  • Modification carried out on 3 grinders

SCCM ALP positions itself as a single provider by providing a turnkey solution including goods and services such as :

  • supply of a set of products (mills, piping, dosing screws, deburring system, hopper…)
  • installation services (electrical installation)
  • services for adjusting the automatisms to be able to supply the quantity of shredded material according to the pollution peaks of the incineration process.

Project management and coordination of the various trades is led by our experienced project manager.