Ammonia Removal In Nitrifying Bio filters

  • Expanded Clay Aggregate (ECA®) filter works by removing ammonium from domestic wastewater by a combination of nitrification and ion exchange. 
  • An identical filters material, but without sorptive capacity with respect to ammonium is used as a reference. 
  • The experiment showed that Expanded Clay Aggregate (ECA®) removed more ammonium at high ammonium loading rates than the identical filter material used. This was due to ion exchange of ammonium alongside with nitrification. 

Lightweight Composite Concrete Produced With Watertreatment Sludge And Sawdust:

  • The potential application of a lightweight concrete produced with lightweight composite of the water treatment sawdust and sludge, by determining the possible environmental impact and thermal properties of future residue of this concrete. 
  • In this research, two types of concrete were prepared: 
    • Concrete produced with the Expanded Clay Aggregates mixed sand/cement/ECA and water in a mass ration of 1:2:0.7:0.5 
    • Normal concrete mixed with sand/cement/granite/water in a ratio of 1:5:6:0.8.
  • The thermal properties were carried out by the hot wire parallel method.
  • The results showed that under a low loading rate of ammonium, nitrification of already absorbed ammonium took place.
  • This combined effect of ion exchange and nitrification of ammonium in Expanded Clay Aggregate (ECA®)  Zeolite was carried out in experiment with constant ammonium loading for  up to 8 days and as well as in experiments with daily variations in ammonium loading rate..

Lightweight Composite Concrete Produced With Watertreatment Sludge And Sawdust:

Thermal Properties And Potential Application

  • The potential environmental impact was checked using the guidelines and procedures of the Brazilian Association of Technical Standards (ABNT). 
  • The concrete made with the Expanded Clay Aggregate (ECA®) provide a set of thermal properties ideal for the application of this composite concrete in non-structural sealing elements. 
  • The concentration of aluminum in the extract of the concrete produced with the Expanded Clay Aggregate (ECA®) was much lower than the concentration of aluminum in the water treatment sludge, and this confirms the possible reduction of environmental impact of ECA® for use in concrete.