In the field of advanced wastewater treatment in the pulp and paper industry, the Fenton oxidation process has become a key technical step for achieving compliance with discharge standards or for recycling purposes due to its efficient removal capability of refractory organic compounds. However, this process is highly sensitive to the pH value of the reaction system, and its treatment efficiency is highly dependent on the precise control of the pH value. The Probest PPH-500F series pH electrodes, with their high stability and anti-pollution design, provide reliable online monitoring support for the optimization of the Fenton process.

The sewage treatment station that is a supporting facility for a certain paper-making enterprise in the Central China region is responsible for treating highly concentrated paper-making wastewater to a level that exceeds the national emission standards. The treated wastewater can then be discharged in compliance with standards or reused.

Among them, the Fenton oxidation process section serves as the final chemical barrier before the effluent meets the discharge standards. Its role is of utmost importance - by decomposing residual organic substances that are difficult to remove through biochemical treatment with highly oxidizing hydroxyl radicals, it ensures that indicators such as COD and color meet the discharge requirements. The precise control of pH directly determines the oxidation efficiency of the Fenton reaction and the cost of the reagent. Under this process, the Fenton reagent has the best oxidation effect in an acidic condition with a pH of 3-5. Excessively high or low pH values will significantly reduce the treatment effect.

The ProbestPPH-500F series industrial pH electrodes were installed in the Fenton treatment pool, and real-time data comparisons were made with the existing pH electrodes of a certain Swiss brand in the same working conditions.

Comparison of on-site pH measurement data

Comparison of pH measurement data

Application practice has shown that during long-term operation, the Probest pH electrode has highly consistent measurement values with those of the Swiss brand pH electrode. The output signal is stable without any jumps or abnormal drifts, and it is highly stable over a long period of time, meeting the control requirements for pH measurement accuracy in the Fenton process.

The benefits of applying Probest PPH-500F electrodes in the Fenton section of the wastewater treatment plant of a paper manufacturing enterprise:

The Probest PPH-500F series of industrial pH electrodes offer various options, including the standard model, the anti-fouling salt bridge-free model, and the Teflon salt bridge + ion capture trap model. They can be equipped with various sensitive membranes such as those resistant to high/low temperatures, strong acids/alkalis, hydrofluoric acid, and low impedance. The IP68 protection level combined with high-strength anti-shock sensitive membranes ensures resistance to high-pressure flushing and mechanical collisions, guaranteeing the reliability, measurement accuracy, and response speed of long-term online monitoring. It specifically addresses measurement challenges in complex conditions such as wastewater, high salt content, high heavy metal ions, and high ammonia ions.