Water purification sludge

In this sector, large numbers of small units need simple and effective flue gas treatment systems. NEUTREC^® process technology enables them to respect local regulations. BICAR^®TEC sodium bicarbonate is a highly effective precipitant for sulphur dioxide, the main pollutant from this type of incineration.

Depending on the nature of the waste water sludges, their use as fertiliser often present environmental disadvantages. In this case incineration becomes one recourse for the operator.

The most widespread process is fluid bed incineration. This permits total combustion of the sludge at around of 900°C, with the sludge remaining in the furnace just a few seconds. The homogeneity of the product and its high organic content (70%) make it easy to incinerate. Prior to incineration, the sludges are dehydrated into a paste containing 25-30% of dry matter.

Co-incineration
Where a municipal waste incineration plant exists in the vicinity the thermal station, the sludges can be directed towards an incinerator.
Incineration can take three different forms: Tipping the sludges directly in the waste pit, drying the sludge first and then incinerating it, or injecting fine droplets of paste-like sludge into the furnace.

Performance of sodium bicarbonate:
Bicarbonate effectively neutralises the SOx and HCl generated by this technology and easily meets the emission limit values which will be recommended by the new legislation scheduled for this activity.