An online detection system of chemical oxygen demand（ COD） based on an advanced oxidation of ozone cooperating with UV and multi-sensor integration is developed

which the measurement information of multiple sensors is fused and the oxygen equivalents cost is calculated by organic matter in water. According to numerous experiments

the compensation models for oxygen equivalents about the amount of ozone imports and temperature are established in low and high range respectively

and the COD value after compensation can be worked out. Test results show that the models are accurate and have high multiple correlation coefficient which are over 0. 96 between the measured value and theoretical value

so the models can meet the test requirements.