A large municipal wastewater treatment facility in Helsinki, Finland, is using technology from Gasmet to continuously monitor its greenhouse gas emissions to help in the city’s efforts to combat climate change and also to help improve the wastewater treatment process, the company says.
In contrast to the strict regulatory monitoring that is applied to the quality of water emissions from wastewater plants, little attention is paid to gaseous emissions from from such facilities, but greenhouse emissions from such facilities can be significant, according to Gasmet.
The Viikinmäki wastewater treatment plant was built in 1994 to process wastewater from both domestic and industrial sources. However, the average temperature in Helsinki between December and February is around 25 F, with extremes below -4 F and even -22 F, so the plant was built almost entirely underground to avoid the freezing temperatures. But building the plant underground also made it easier for the plant to comply with local regulations requiring emissions monitoring, Gasmet says.
Gasmet installed a continuous emissions monitoring system at the underground facility in late 2012.
The plant’s emissions for methane in 2013 were around 350 tons, and for nitrous oxide around 134 tons. This means that the emissions per cubic meter of wastewater equate to 3.5g of methane and 1.34g of nitrous oxide, Gasmet says.
In May last year, Gasmet launched a flue gas continuous mercury monitoring system. The system employs cold vapour atomic fluorescence to produce low detection limits. The company says it costs less than other comparable mercury monitoring instruments and has low operational costs because it doesn’t require separate chemicals, amalgamation concentrators, air scrubbers or additional gases. Gasmet has so far installed systems in Finland and Poland.