Experiments in monitoring the removal of organic material and nitrogen and determining the amounts of mi- croorganism at different sites in the subsurface flow constructed wetland in Sihong county were performed. The ...Experiments in monitoring the removal of organic material and nitrogen and determining the amounts of mi- croorganism at different sites in the subsurface flow constructed wetland in Sihong county were performed. The results show that the removal of CODCr agrees with the kinetic equation of a first order reaction. The removal of pollutants varies with different seasons. The removal rates of CODCr, NH3-N, TN in the spring are 15%–23% higher than those in the autumn. The amount of ammonifier is larger than that of denitrifying bacteria and the amount of denitrifying bacte- ria is larger than that of nitrosomonas. The amount of bacteria around the plant roots is larger than that on the surface of the packing medium. No apparent change is observed for the amount of denitrifying bacteria and nitrosomonas between spring and autumn.展开更多
Carbonation of concrete is a process which absorbs carbon dioxide (CO2). Recycled aggregate concrete(RAC) may own greater potential in CO2 uptake due to the faster carbonation rate than natural aggregate concrete (NAC...Carbonation of concrete is a process which absorbs carbon dioxide (CO2). Recycled aggregate concrete(RAC) may own greater potential in CO2 uptake due to the faster carbonation rate than natural aggregate concrete (NAC).A quantitative model was employed to predict the CO2 uptake of RAC in this study. The carbonation of RAC and thespecific surface area of recycled coarse aggregates (RCAs) were tested to verify accuracy of the quantitative model. Basedon the verified model, results show that the CO2 uptake capacity increases with the increase of RCA replacementpercentage. The CO2 uptake amount of 1 m^3 C30 RAC within 50 years is 10.6, 13.8, 17.2, and 22.4 kg when the RCAreplacement percentage is 30%, 50%, 70%, and 100%, respectively. The CO2 uptake by RCAs is remarkable and reaches35.8%- 64.3% of the total CO2 uptake by RAC when the RCA storage time being 30 days. Considering the fact that theamount of old hardened cement paste in RCAs is limited, there is an upper limit for the CO2 uptake of RCAs.展开更多
文摘Experiments in monitoring the removal of organic material and nitrogen and determining the amounts of mi- croorganism at different sites in the subsurface flow constructed wetland in Sihong county were performed. The results show that the removal of CODCr agrees with the kinetic equation of a first order reaction. The removal of pollutants varies with different seasons. The removal rates of CODCr, NH3-N, TN in the spring are 15%–23% higher than those in the autumn. The amount of ammonifier is larger than that of denitrifying bacteria and the amount of denitrifying bacte- ria is larger than that of nitrosomonas. The amount of bacteria around the plant roots is larger than that on the surface of the packing medium. No apparent change is observed for the amount of denitrifying bacteria and nitrosomonas between spring and autumn.
基金Support from the National Natural Science Foundation(NSFC)of China(Grant No.51808399)Chinese-Japanese Research Cooperative Program sponsored by Ministry of Science and Technology in China(No.2016YFE0118200).
文摘Carbonation of concrete is a process which absorbs carbon dioxide (CO2). Recycled aggregate concrete(RAC) may own greater potential in CO2 uptake due to the faster carbonation rate than natural aggregate concrete (NAC).A quantitative model was employed to predict the CO2 uptake of RAC in this study. The carbonation of RAC and thespecific surface area of recycled coarse aggregates (RCAs) were tested to verify accuracy of the quantitative model. Basedon the verified model, results show that the CO2 uptake capacity increases with the increase of RCA replacementpercentage. The CO2 uptake amount of 1 m^3 C30 RAC within 50 years is 10.6, 13.8, 17.2, and 22.4 kg when the RCAreplacement percentage is 30%, 50%, 70%, and 100%, respectively. The CO2 uptake by RCAs is remarkable and reaches35.8%- 64.3% of the total CO2 uptake by RAC when the RCA storage time being 30 days. Considering the fact that theamount of old hardened cement paste in RCAs is limited, there is an upper limit for the CO2 uptake of RCAs.
