Sewage treatment process with magnetic sludge carbon carrier cooperated with standard upgrading and capacity improvement

A sewage treatment process comprising the following steps:

• Step 1:
• performing a primary treatment on the sewage and removing suspended solid pollutants after the primary treatment for the sewage, and placing the treated sewage without the suspended solid pollutants into a secondary biochemical treatment section;
• Step 2:
• mixing a magnetic sludge carbon carrier and a solvent to prepare a first mixed solution which is then placed into the secondary biochemical treatment section synchronously with the sewage;
• Step 3:
• uniformly mixing the sewage, the magnetic sludge carbon carrier and activated sludge in a first biochemical treatment section to form a second mixed solution, in which microorganisms are attached on a surface of the magnetic sludge carbon carrier and adsorbed in its interior channels, and multiply in number to generate a composite biofilm;
• Step 4:
• performing a dreg-water separation in a sedimentation tank on the second mixed solution flowing out of the secondary biochemical treatment section, thereby forming a supernatant that flows into an advanced treatment section and is discharged after reaching a predefined standard, and one part of sediments, which are composite carrier particles, are refluxed to a front influent end of the secondary biochemical treatment section and a second part of the sediments thereof are magnetically separated;
• Step 5:
• recycling magnetic particles, in which the magnetic particles are reclaimed to the front influent end of the secondary biochemical treatment section, and the remaining non-magnetic suspended sludge particles are processed jointly by a sludge dewatering process and a carbonization process to generate the magnetic sludge carbon carrier.