Processing of the liquid fraction

Concentration by vacuum evaporation

Concentration by vacuum evaporation

Objective

Concentration of nutrients and organic matter through the evaporation of water at a temperature below 100ºC and at pressures below the vapor pressure of the liquid

Inlets

Water flow from other processes (see combination with other technologies)

Efficiency

Concentrate with a solids content of 25-35%; more than 98% nitrogen recovery if the pH is kept below 5.5

Weaknesses

The presence of heavy metals in the concentrate can limit the application of the product in the field;
Need for reagents (strong acids) to maintain the pH at 5.5 and ensure N recovery;
Forms of sulfur may appear in the condensate if acidification is carried out with sulfuric acid);

Products

Concentrate (nutrients in the form of ammonium, organic matter)

Other outlets

Condensate (water vapor)

Consumption

Energy: Medium
Water: Not applicable
Reagents: Low

Investment

Not available

Operation

Not available

Observations

Choose materials resistant to high temperatures and low pHs (quality stainless steel > 316 L);
Need for operator training to avoid accidents due to working with strong acids.

Combination with other technologies

1. Coagulation-flocculation or Separation by centrifugation -> microfiltration -> reverse osmosis -> vacuum evaporation;
2. Coagulation-flocculation or Separation by centrifugation -> microfiltration -> vacuum evaporation;
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TRL - 9
Status Consolidated
Complexity High

Information made by:

BETA Tech Center