Why is wastewater treatment important?
Wastewater poses a serious burden on the environment and can have harmful effects on our surroundings if it is not properly managed and disposed of. Therefore, effective wastewater treatment solutions are essential. They ensure that the water is thoroughly cleaned before being returned to nature.
Disposal of industrial wastewater is an important task that requires effective and environmentally friendly methods. The most common treatment processes include physical, chemical, biological, and thermal treatments – as well as water reuse and recycling.
An ENVOTHERM system combines thermal treatment with water reuse.
Laboratory report
This laboratory report presents measurements of heavily polluted wastewater from a Danish railway company—both before and after treatment with our ZLD unit (Zero Liquid Discharge). The results show a significant reduction in all parameters—and remarkably, this has been achieved without the use of activated carbon. With the addition of activated carbon, both conductivity and oil/fats can be completely removed.
Before evaporation
| pH chemical parameters | ||
| pH value (laboratory measurement)) | 10,2 | |
| Conductivity at25 °C | µS/cm | 38000 |
| Anions | ||
| Chloride (Cl⁻) | Mg/l | 1100 |
| Sulfate (SO₄²⁻) | Mg/l | 1000 |
| Total cyanide | Mg/l | 0,34 |
| Overview parameters | ||
| Oil and grease (total) | Mg/l | i.k |
| Oil (non-polar fraction) | Mg/l | i.k |
| Sediment | Mg/l | <0,033 (lod) |
| Total Suspended Solids | Mg/l | 560 |
| Inorganic trace elements | ||
| Arsenic (As) | µS/I | 195 |
| Lead (Pb) | µS/I | 12700 |
| Cadmium (Cd) | µS/I | 69,7 |
| Chromium (Cr) | µS/I | 7100 |
| Copper (Cu) | µS/I | 13600 |
| Mercury(Hg) | µS/I | <0,0300 (LOD) |
| Molybdenum (Mo) | µS/I | 5750 |
| Nickel (Ni) | µS/I | 16800 |
| Selenium (Se) | µS/I | 29,6 |
| Silver (Ag) | µS/I | 23 |
| Zinc (Zn) | µS/I | 173000 |
| Cobolt (Co) | µS/I | 0,757 |
| Tin (Sn) | µS/I | 3,35 |
After evaporation (without any post-processing)
| pH and chemical parameters | ||
| pH value (laboratory measurement | ) | 10,4 |
| Conductivity at 25 °C | µS/cm | 470 |
| Anions | ||
| Chlorid (Cl⁻) | Mg/l | <1,0(+) |
| Sulfate (SO₄²⁻) | Mg/l | 7,2 |
| Total cyanide | Mg/l | <0,010 (lod) |
| Overview parameters | ||
| Oil and grease (total) | Mg/l | 280 |
| Oil (non-polar fraction) | Mg/l | 9,8 |
| Sediment | Mg/l | <0,033 (lod) |
| Total Suspended Solids | Mg/l | 6,4 |
| Inorganic trace elements | ||
| Arsenic (As) | µS/I | 4,9 |
| Lead (Pb) | µS/I | <1 (lod) |
| Cadmium (Cd) | µS/I | <0,03 (lod) |
| Chromium (Cr) | µS/I | 7 |
| Copper (Cu) | µS/I | 26 |
| Mercury (Hg) | µS/I | <0,0300 (LOD) |
| Molybdenum (Mo) | µS/I | 2,6 |
| Nickel (Ni) | µS/I | 9 |
| Selenium(Se) | µS/I | <0,24 (+) |
| Silver (Ag) | µS/I | <1 (lod) |
| Zinc (Zn) | µS/I | <90 (+) |
| Cobolt (Co) | µS/I | <0,010 |
| Tin (Sn) | µS/I | 0,06 |