Controlling CH4 Emissions from Integrated Vertical-Flow Constructed Wetlands by Using Potassium Peroxymonosulfate (PMS) as Oxidant

Abstract

\n It is very important to control methane emissions to reduce global warming. In this study, an attempt was made to adjust the oxidation-reduction potential (Eh) by adding different mass of potassium peroxymonosulfate (PMS) (0 g, 31.25 g, 62.5 g, 125 g, 250 g and 500 g) to reduce methane from integrated vertical-flow constructed wetlands (IVCW). Results show that the reduced CH4 emission from IVCW was the highest with decreased by 43.5% compared to blank group (PMS=0), when adding 125g PMS. Importantly, the reduced CH4 from the root-water system of IVCW was higher than that of the stem-leaf system of IVCW, when adding PMS. It’s found that Eh not only has a significant correlation with CH4 flux, but also has a significant relationship between PMS quality, DO, water temperature and sampling time (yEh= -0.44XPMS + 6.82XDO + 0.38t - 264.1, R2 = 0.99). It concludes that PMS, as an oxidant, is a very feasible method for controlling methane emissions from IVCW. Further research may combine other methods such as microbiology, physical control and hydrology control for mitigating the CH4 emissions from constructed wetlands.