Removal of chemical oxygen demand, total phosphorus, and ammonia nitrogen from pickle wastewater by plant biomass carbon combined with a chemical oxidant

The pickled wastewater with high concentrations of chemical oxygen demand (COD), total phosphorus (TP), ammonia nitrogen (NH₄⁺-N), and sodium chloride (NaCl) has an adverse effect on the environment, and it is challenging to treat pickle wastewater efficiently by traditional biological methods. It is urgent to develop reasonable treatment methods for ensuring water quality and security. Thus, the purposes of this study were to (1) examine the effect of various factors on the removal efficiency of pollutants (COD, TP, and NH₄⁺-N) from simulated pickle wastewater by plant biomass carbon (PBC) and (2) determine the best technical parameters and verify the treatment effect of real pickle wastewater. The adsorbent type and action mode had a significant impact on removing COD, TP, and NH₄⁺-N in the simulated pickle wastewater. The Fenton oxidant could significantly improve the COD removal rate. The quality difference had no significant effect on removing COD and TP. However, the difference between 0.2 and 0.4 g had a significant impact on removing NH₄⁺-N. The optimal treatment was found by P3 (0.4 g, first use) and a Fenton oxidant oscillating for 120 min. The removal rates of COD, TP, and NH₄⁺-N in real pickle wastewater were 53.06%, 79.96%, and 8.06%, respectively, using optimized parameters.