The laboratory comprehensive wastewater treatment equipment achieves deep purification of complex wastewater through four core processes: oxidation, adsorption, flocculation, and membrane separation. Its working principle is as follows:
Oxidation process is a key step in the degradation of organic pollutants. The device is equipped with an ozone generator, which generates ozone through high-voltage discharge and utilizes its strong oxidizing properties to destroy the molecular structure of organic matter. For example, ozone can oxidize difficult to degrade substances such as phenols and aldehydes in wastewater, converting them into carbon dioxide and water, while killing bacteria, viruses, and other microorganisms. For high concentration organic wastewater, the equipment can also use Fenton oxidation technology. Under acidic conditions, hydrogen peroxide reacts with ferrous ions to generate hydroxyl radicals, which have strong oxidation ability and can mineralize organic matter, resulting in a COD removal rate of over 90%.
The adsorption process intercepts pollutants through porous media. Activated carbon is a commonly used adsorbent with a large specific surface area, which can adsorb heavy metal ions, organic matter, and pigments in wastewater. For example, the adsorption capacity of activated carbon for mercury ions can reach 50mg/g, and the adsorption rate for phenol exceeds 95%. In addition, the equipment can also adopt macroporous resin adsorption technology, which selectively adsorbs specific substances such as phenols, surfactants, etc. through the pore structure of the resin. After adsorption saturation, it can be regenerated through dilute alkali solution to achieve resource recycling.
The flocculation process uses chemical agents to cause colloidal particles to aggregate and settle. The equipment adds flocculants such as polymeric ferric sulfate and polyacrylamide to form large flocs of suspended solids, colloids, and some organic matter in the wastewater. For example, polymeric ferric sulfate can remove 60% of emulsified oil and 10% -20% of COD at pH 6-8, and the settling rate of flocs can reach 0.5m/h, significantly reducing the subsequent treatment load.
The membrane separation process achieves material separation through the selective permeability of the membrane. The equipment uses ultrafiltration membranes (pore size 0.001-0.1 μ m) to remove proteins, colloids, and bacteria. Nanofiltration membranes (pore size 0.001-0.002 μ m) intercept divalent salts and small molecule organic matter, while reverse osmosis membranes (pore size<0.0001 μ m) can remove almost all solutes. For example, reverse osmosis technology can reduce the salt concentration in wastewater to below 500mg/L, meeting the reuse standards.