Effect of Fenton conditioning on the reduction of lead-containing industrial sludge by electroosmotic dewatering

Aiming at the difficulty of dewatering and realizing volume reduction of the lead-containing industrial sludge produced from lead-acid battery plants, Fe²⁺ in the sludge was used to perform Fenton preconditioning, and the effect of different dosages of hydrogen peroxide on the subsequent electroosmotic dewatering and reduction of the sludge was explored. The experimental results showed that the sludge pretreated by Fenton conditioning would break some of the flocs and reduce sludge viscosity from 18.0 mPa·s to 4.7 mPa·s. Part of the inorganic ions in the sludge left the solid phase system and entered the filtrate during the dewatering process, resulting in the water content of the subsequent electroosmotic dewatered sludge cake reducing from 82.72% to 69.34% and the content of volatile suspended solids increasing about 30%. Compared with the direct dewatering of the original sludge, the optimized H₂O₂ addition could promote the subsequent reduction of 66.20% of sludge by electroosmotic dewatering. At the same time, Pb content in the dry basis was increased from 265.2 g/kg to 453.6 g/kg, which was beneficial for the subsequent resource utilization or harmless landfill treatment of the sludge.