The Removal Of Ammonia Nitrogen And Total Phosphorus From Anaerobic Digested Alcohol Wastewater By Eichhornia Crassipes

With the growing demand for alcohol, the alcohol plants produced more and more wastewater. We usually using the traditional treatment, anaerobic fermentation and aerobic fermentation, to deal with the alcohol wastewater at the present. The purpose of aerobic fermentation is to remove the nitrogen and phosphorus in anaerobic digested alcohol wastewater. But as we all know, the consumption and operation costs of aerobic fermentation is so high that it goes against with the principle of energy conservation and environmental protection. So this article is aim at finding a new process, which is effective and more environmental-friendly, to treat the anaerobic digested alcohol wastewater. Eichhorniacrassipes can grow up very fast and it needs a lot of ammonia nitrogen and phosphorus during its growing. So it can obviously reduce the content of ammonia nitrogen and total phosphorus in wastewater to lower the degree of eutrophication. At the present, the eutrophication wastewater that Eichhorniacrassipespurified has not involved anaerobic digested alcohol wastewater, therefore, this article explored the most fitting concentration of anaerobic digested alcohol wastewater to Eichhorniacrassipes’ growth and the removal of ammonia nitrogen and total phosphorous from anaerobic digested alcohol wastewater by Eichhorniacrassipes in different hydraulic loading baffle constructed wetlands has been studied also. Moreover, this study discussed the influence of different LED light qualities on Eichhorniacrassipestreating anaerobic digested alcohol wastewater and Eichhorniacrassipes’ self-growth, because the artificial light is the main obstacles for further development of Eichhorniacrassipes in treating anaerobic digested alcohol wastewater when the temperature is not that suitable for Eichhorniacrassipes’ growth, winter for example. The main results are as follows:(1) 10% concentration of anaerobic digested alcohol wastewater is the fittest concentration to Eichhorniacrassipes’ growth. In that concentration, the fresh weight of Eichhorniacrassipes increased 397% in 10 days, which is the most amongst all the concentration. And the speed of the removal of ammonia nitrogen and total phosphorous by Eichhorniacrassipes is the fastest in that concentration. And the content of ammonia nitrogen and total phosphorous can reach to the national standard A respectively at the 6th and 10 th day.(2) The speed of the removal of ammonia nitrogen and by Eichhorniacrassipes in 20% concentration of anaerobic digested alcohol wastewater is slow. At the 22 th day, the content of ammonia nitrogen and total phosphorous are still high. The content of ammonia nitrogen is 75.11mg/L and the content of total phosphorous is 13.04mg/L, which is far beyond the national standard A. And the fresh weight of Eichhorniacrassipes in 20% anaerobic digested alcohol wastewater increased a bit, only 47.96% at the 22 th day.(3) The Eichhorniacrassipes’ leaves in 25% concentration of anaerobic digested alcohol wastewater started to turn yellow from the bottom and became withering from the 1th day. So the Eichhorniacrassipes can hardly absorb ammonia nitrogen and total phosphorous. The content of ammonia nitrogen is 135.44mg/L and the content of total phosphorous is 22.6mg/L, which means that it just remove31.16% ammonia nitrogen and 8.16% phosphorous. What’s more, the fresh weight of Eichhorniacrassipes in 25% concentration of anaerobic digested alcohol wastewater was reducing from the 1th day and just keep 52.04% stay at the 16 th day.(4) Eichhorniacrassipes can obviously remove the ammonia nitrogen and total phosphorous of 10% concentration of anaerobic digested alcohol wastewater in baffle conducted wetlands. The ammonia nitrogen and total phosphorous content of wastewater purified by Eichhorniacrassipes is varied in hydraulic loading. There is a positive correlation between them. When the hydraulic loading is 34.48L·m-2·d-1, the ammonia nitrogen content of 10% concentration of anaerobic digested alcohol wastewater purified by Eichhorniacrassipes is 4.19mg/L and the content of phosphorus is 0.080mg/L, which can reach the national standard A. And the reduction of ammonia nitrogenby Eichhorniacrassipes is the maximum when the hydraulic loading is 62.07L·m-2·d-1. What’s more, the content of total phosphorus can reach the national standard A also, but the content of ammonia nitrogen, which is 16.63 mg/L, can not meet the requirement of the national standard A.(5) The removal efficiency of ammonia nitrogen and total phosphorus made by Eichhorniacrassipes under red and blue LED lights is higher than the control group: white LED lights. The removal rate of ammonia nitrogen and total phosphorus is 72.62% and 64.37% under white LED lights. The removal efficiency of ammonia nitrogen and total phosphorus made by Eichhorniacrassipes under only red or blue LED lights is lower than red- blue LED lights. The rate of ammonia nitrogen and total phosphorus cleaned up by Eichhorniacrassipes under red LED lights is 91.7%(at the 10 th day) and 83.91%(at the 17 th day) respectively which is higher than the Eichhorniacrassipes under blue LED lights’ 89.66%(at the 10 th day) and 82.99%(at the 17 th day). The removal efficiency of ammonia nitrogen and total phosphorus is varied in the ration of red/blue when both two color LED light are exist at the same time. The bigger the ration of red/blue is, the removal effect turns into better. When the ration of red/blue is 8:1, the removal effect is the best. The removal efficiency of ammonia nitrogen and total phosphorus are 97.11% and 90.34% respectively at the end of detection. And the self-growth of Eichhorniacrassipes under this LED light is also the best. The leaves of Eichhorniacrassipesincreased 35.3 slices and the tiller increased 8 and the fresh weight increased 619% at the 17 th day.(6) The root of the Eichhorniacrassipesunder red LED light grows most quickly. It increased 5 cm in 17 days. But red LED light is inhibition for the growth of Eichhorniacrassipes’ stem. The stem decreased 3.8 cm in 17 days. And the stem of the Eichhorniacrassipesunder white LED light increased 2cm. But the Eichhorniacrassipesunder blue LED light presented the opposite phenomenon. The root stay the same at the 17 th day which is smaller than CK’s 1.1cm and the stem increased 4.4cm which is the biggest among all the LED light.