Forecasting of urban wastewater discharge based on Gray-Markov Model
基于灰色马尔可夫模型的城市污水量预测

The urban wastewater discharge can provide fundamental data for drainage engineering design, the Gray System Theory is widely used to forecast urban wastewater discharge. Based the urban wastewater discharge in Tianjin from 2001 to 2009, Gray Model was established to forecast the discharge of domestic sewage and industrial wastewater in Tianjin from 2010 to 2015. As the data of industrial wastewater was characterized as great fluctuation, Markov Model was introduced to amend the results of Gray Model. The results showed that the forecasting results of industrial wastewater by Gray Markov Model had high accuracy. The domestic sewage discharged would be 651.2057 million tons and the industrial wastewater discharged would be 193.3939 million tons in 2015. It indicated that the percentage of domestic sewage discharge in urban wastewater discharge having an increase trend as time goes on.