High-sulfur-content and high-COD (Chemical Oxygen Demand) wastewater treatment process

The invention provides a high-sulfur and high-COD (Chemical Oxygen Demand) wastewater treatment process, which is used for treating gas field wastewater with the sulfide content of more than 500mg/L, the COD of more than 15000mg/L and the ammonia nitrogen content of less than 100mg/L. The treatment process comprises the following steps: carrying out negative pressure desulfurization treatment on sulfur-containing wastewater to obtain H2S and desulfurized wastewater; the method comprises the following steps: adjusting the pH value of the desulfurization wastewater to 2-4, mixing H2O2 with the concentration of 1.5-4.5% and the desulfurization wastewater according to the volume ratio of (50-110) ml: 1 L, and adding Fe < 2 + > according to the ratio of n (Fe < 2 + >): n (H2O2) of 1: (15-25) to obtain desulfurized and organic matter-removed wastewater; adding sodium hypochlorite into the desulfurized and organic matter-removed wastewater to obtain desulfurized and organic matter-removed ammonia nitrogen-removed wa