The invention discloses a method and
system for treating high-
ammonia nitrogen photovoltaic waste water containing
cadmium and
thiourea. The high-
ammonia nitrogen photovoltaic waste water containing
cadmium and
thiourea enters a primary comprehensive
cadmium removing
pool, NaOH, PAC and PAM are added in order for carrying out a coagulation reaction, cadmium precipitates are added into the waste water, NaOH is added for adjusting a pH value and the waste water enters a
distillation stripper, and at the same time
ammonia nitrogen in the waste water is recycled and converted into 16-19% ammoniacal liquor;
effluent enters a secondary integrated cadmium removing
pool, NaOH, TMT, PAC and PAM are added in order for carrying out a coagulation reaction, and a
secondary treatment is carried out for residual cadmium substances in water;
effluent enters an advanced oxidation
pool, agent H2SO4, FeSO4, H2O2, and NaClO are added in order, and oxidation and
decomposition are carried out for
thiourea substances and residual
ammonia nitrogen in the waste water;
effluent enters a coagulative
precipitation tank, agent NaOH, TMT, PAC and PAM are added in order, residual cadmium in water and oxidation products in the advanced oxidation technology are removed, and
water quality of discharged water reaches a B grade standard in '
wastewater quality standards for
discharge to municipal sewers' (GJ343-2010).