Submerged Combustion For Treatment Of High Concentration Organic Waste Water

There are some problems in the process of dealing with high concentration organic wastewater by using common biological methods,such as the treatment cycle is long and the effect is poor when dealing with refractory toxic substances.And macromolecule organic matter of high concentration organic wastewater can be completely oxidized at high temperature,into carbon dioxide,water,nitrogen oxides and other small molecules.It is more reasonable and economical to use the incineration method when dealing with high concentration organic wastewater.In this paper,submerged combustion technology is applied to the incineration process of high concentration organic wastewater.On the basis of this submerged combustion technology,an immersion burner was designed and manufactured.It was made up of burner,combustion chamber,immersion tube,defogger,sewage outfall and other components.In the self-built immersion combustion device,this paper carried out a high concentration organic wastewater experimental study.The effects of excess air ratio,secondary air volume,immersion depth,combustion temperature and mixed amount of waste water on the incineration characteristics and exhaust emissions of high concentration organic wastewater were investigated.The results show that the industrial wastewater contains a certain amount of organic matter and alkali metal salt,and it is obvious to remove oganic matter in the tube furnace.As the temperature increases,the combustion efficiency and COD removal rate increase.In the experimental temperature range,the NOx of industrial waste is mainly derived from the rapid NOx and fuel type NOx.The main source of the NOx solution in the combustion process is the rapid NOx.The organic sulfide and trace sulfide acid of industrial wastewater will produce SO2 in the incineration process.The effects of excess air ratio,secondary air volume,immersion depth,combustion temperature and mixed amount of wastewater on the incineration characteristics and exhaust emission of high concentration organic wastewater were studied on the self-propelled immersion burner.The results show that the removal efficiency of organic matter in high concentration organic wastewater is obvious,and the increase of secondary air volume and excess air coefficient can improve the combustion efficiency and reduce CO emission.While the increase in temperature and immersion depth leads to an increase in NOx emissions in the tail gas.With the increase of temperature and immersion depth,COD removal rate is improved.When the temperature is above 900?,the immersion depth reaches to 20cm,COD removal rate can reach more than 90%.Fluent was used to study the gas-liquid flow in the horizontal submerged tube.Studies have shown that the bubble in the shape of a round hat-shaped,spread to the surrounding.Bubbles with downward velocities will penetrate down a distance and then rise.In the process of the rise,the bubbles will squeeze the liquid,and the gas-liquid flow effect is obvious.It will lead to pressure fluctuations.With the increase of inlet air velocity,the disturbance intensity between gas and liquid is enhanced and the bubble puff is more obvious.With the increase in the depth of immersion,pressure fluctuations will increase,the role of gas-liquid two-phase will be more fully.In the actual process,excessive pressure fluctuations will lead to instability in the furnace combustion,so it is necessary to select the appropriate immersion depth.