The Distribution and Temporal Change of Mercury in a Sewage Treatment Plant

DOI

10.2991/meic-15.2015.122How to use a DOI?

Keywords

THg;Dissolved THg;MeHg;Dissolved MeHg;Pressure-filter sludge

Abstract

In order to understand the distribution characteristics and temporal change of mercury species in a sewage treatment plant,sewage and sludge samples were collected from influent and effluent of the Second Sewage Treatment Plant of Jiaozuo for 10 months.Atomic Fluorescence method was used to detect mercury.Total mercury (THg) and methylmercury (MeHg) were found the average concentrations of 2.00×103ng/L and 16.2ng/L.THg in grit chamber mainly exists with granule state.THg were positively correlated to TSS (P=0.003). MeHg and dissolved MeHg of influent were found at average concentrations of 7.5ng/L and 0.59ng/L.Inffluent THg and MeHg concentrations have correlation with TSS concentrations (P=0.003, P=0.035).Dissolved MeHg was increases with the temperature rising. THg and Dissolved THg of effluent were found at the average concentrations of 10.6ng/L and 2.2ng/L. Mean daily removals of THg and dissolved THg at the plant were 98.9% and 65%. The ratio (Dissolved THg/THg) has increased in effluent.MeHg and dissolved MeHg of effluent were found that the average concentrations of 0.33ng/L and 0.1ng/L. THg and MeHg contents of the effluent met the requirement of "Urban sewage treatment plant pollutant discharge standard" (GB18918-2002). Mean daily removals of MeHg and dissolved MeHg were 93.5% and 70.7%. MeHg removal efficiency is higher than dissolved MeHg removal efficiency and the MeHg removal efficiency is lower than the THg removal efficiency.The pressure-filter sludge ( (3.94±0.53) ×103ng/g) was  greater than the national standard for soil environmental quality of grade iii.The average concentrations of MeHg was 6.35±0.84ng/g.The ratio of MeHg accounted for THg was minimal(less than 1%). Using the Index of geoaccumulation and potential ecological risk index method to analysis THg in pressure-filter sludge.The result of indicated that THg in pressure-filter sludge have high potential ecological risk.Thus the sludge might not be applied to farm land after suitable treatments.

Copyright

© 2015, the Authors. Published by Atlantis Press.

Open Access

This is an open access article distributed under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

Download article (PDF)

TY  - CONF
AU  - Ying Cui
AU  - Bingjuan Ma
PY  - 2015/04
DA  - 2015/04
TI  - The Distribution and Temporal Change of Mercury in a Sewage Treatment Plant
BT  - Proceedings of the 2015 International Conference on Mechatronics, Electronic, Industrial and Control Engineering
PB  - Atlantis Press
SP  - 531
EP  - 538
SN  - 2352-5401
UR  - https://doi.org/10.2991/meic-15.2015.122
DO  - 10.2991/meic-15.2015.122
ID  - Cui2015/04
ER  -