Analysis On The Efficiency Of Integrated Vertical Flow Constructed Wetland On The Low Concentration Rubber Wastewater Treatment

The wastewater treatment process and operation condition of20natural rubber processing factories are researched in Hainan Province. The Basic properties of the waste water and waste water treatment facilities and ability of wastewater treatment were surveyed. On this basis, the field test was used to research the removal efficiency of Integrated Vertical Flow Constructed Wetland with coconut husk and gravel and coarse sand on the low concentration rubber wastewater treatment. The water quality in the influent and the effluent was monitored, the water hydraulic loading of wetland system was optimized and the growth of forage and nutritional quality in the wetland system were researched. There are the results.The expenses of rubber wastewater treatment are not much in the private natural rubber processing factories in Hainan province. Nearly40%of processing plant failed to achieve the requirements of natural rubber processing waste water pollution discharge standards. The nature environment emissions would cause ecological pollution, and it is a waste of resources if the rubber wastewater would not be used. Integrated Vertical Flow Constructed Wetland was added in the original wastewater treatment facilities to purify water quality which can meet the emissions standards or the water reuse standard.The Treatment effect of integrated vertical flow constructed wetland system for the low concentration of waste water is stable. The concentrations of COD, BOD5, NH3-N and TP were192.29mg·L-1,29.35mg·L-1and40.69mg·L-1in the influent of the wetland. The removal rate of COD, NH3-N and TP were68.9%,59.5%and75.2%respectively in the wetland system with coconut husk.The removal rate of COD, NH3-N and TP were67.9%,60.1%and72.9%respectively in the wetland system with gravel. The removal rate of COD, NH3-N and TP were44.4%,43.9%and55.1%respectively in the wetland system with coarse sand.The influence of constructed wetland substrate for the waste water treatment in the wetland system was significant. The concentrations of COD, BOD5, NH3-N and TP were59.48mg·L-1,14.93mg·L-1,16.44mg·L-1and7.27mg·L-1in the wetland system with coconut husk.The concentrations of COD, BOD5and NH3-N, TP were61.50mg·L-1,13.81mg·L-1,16.19mg·L-1and7.93mg·L-1in the wetland system with gravel. The concentrations of COD, BOD5, NH3-N and TP were106.27mg·L-1,25.02mg·L-1,22.76mg·L-1and13.19mg·L-1in the wetland system with coarse sand. The contrast of the treatment effect was that the coconut husk was the best and the gravel was better than coarse sand.The treatment was effected by the the hydraulic load,The concentrations of COD,NH3-N and TP were59.80mg·L-1,16.38mg·L-1and7.33mg·L-1in the wetland system with coconut husk at the hydraulic load of144mm·d-1.The concentrations of COD,NH3-N and TP were93.64mg·L-1,23.02mg·L-1and10.80mg·L-1in the wetland system with coconut husk at the hydraulic load of288mm·d-1.The concentrations of COD,NH3-N and TP were70.32mg·L-1,20.28mg·L-1and7.89mg-L-1in the wetland system with coconut husk at the hydraulic load of216mm·d-1.All of the results can meet the Emissions standards.The treatment was effected by concentrations of the pollutants in the influent of wetland. The concentrations of COD,NH3-N and TP were27.18mg·L-1,13.16mg·L-1and5.15mg·L-1in the effluent of wetland system if the concentrations of COD,NH3-N and TP were119.34mg·L-1,30.74mg·L-1and21.71mg·L-1in the influent of the wetland system with coconut husk.The concentrations of COD,NH3-N and TP were22.92mg·L-1,14.53mg·L-1,4.15mg·L-1in the effluent of wetland system if the concentrations of COD,NH3-N and TP were77.96mg·L-1,23.96mg·L-1and18.08mg·L-1in the influent of the wetland system with coconut husk..The concentration of NH3-N has a little rise and the concentrations of COD and TP would decrease.Analysis and research of the wetland grass growing condition through the long-term observation. The results show that the rubber wastewater is beneficial to the growth of the grass, the growing condition of grass is very well in the wetland with gravel and coconut, the average height of plants are200cm, the average crude protein content were13.4%and14.2%, the average crude fiber content were52.3%,54.2%. They were higher than those in the control group which were180cm,10.7%,49.0%. It shows that the using of rubber wastewater can improve the nutritional value of the plants. It could make full use of resources and have certain economic benefits.In a word, the purification effect of Integrated Vertical Flow Constructed Wetland with coconut husk and gravel and coarse sand on the low concentration rubber wastewater treatment was useful. The main pollutant removal rate is high. It can make the water quality to achieve the waste water reuse and agriculture irrigation requirements. By the way, it also makes full use of the water resources. The using of gravity form as a system dynamics could save the energy and the operating cost is low. It makes the management convenient and has ecological benefits. Accordingly, the system of waste water treatment is worth to extend.