Alkaline waste water must be neutralized before it is discharged into a receiving watercourse or into the sewage treatment plant. At the same time, it is important to prevent the organic waste water from rotting, the resulting odor and the deposition of suspended substances in the reactor.
All the above-mentioned tasks – neutralization, oxygenation and good tank mixing – can be achieved simultaneously in FRINGS PROREACT N – neutralization systems in an optimal way.
PROREACT N – neutralization systems consist of a reactor in tower design. The respective size and number of the reactors depends mainly on the amount of water, the pH-values and the neutralization target required by law.
When selecting the materials for the reactors, a wide variety of materials can be used:
The core of the neutralization plant is the FRINGS submerged aerator, which is installed on the reactor bottom and connected to the carbon dioxide source and the atmosphere by means of piping.
The submerged aerator automatically sucks in air, mixes it intensively with the waste water and distributes the waste water-air mixture evenly and fine-bubbled in the reactor. The rising air ensures a vigorous mixing of the entire reactor volume.
If the pH value exceeds the limit set by the authorities, a pH measuring and control device automatically switches over to flue gas suction or doses carbon dioxide into the air suction line.
Once the waste water has been sufficiently neutralized, the system switches back to air intake or interrupts the CO2 dosing, while the submersible aerator continues to provide oxygen intake and good tank mixing.
Carbonic acid, either in pure form or as a component of flue gas, is an inexpensive and non-corrosive neutralizing agent. Acidification of the waste water by carbon dioxide is impossible and makes the use of corrosive acids as neutralizing agents, which leads to increased chloride contamination, unnecessary.
Only high-quality materials and components are used for the neutralization plants, which guarantee long service life with low maintenance.
The entire process is automated to the greatest possible extent and normally only requires routine maintenance work, e.g. calibration of the probes.