Germany looks to Australian supplier for flowmeters

German mining company RWE Power has ordered 25 ABB AquaMaster electromagnetic water meters to help preserve groundwater based marshes and wetlands around its German coal mines.

The meters monitor the amount of water being pumped back into the nature reserves from RWE's open cast lignite mines, where constant pumping is needed to control groundwater levels in three big mines.

RWE previously using mechanical flowmeters to measure water pumped back to the marshes.

The need for more accurate measurement of water flows and automatic data monitoring made electronic flowmeters an attractive proposition. However, with many of the meters located beyond the reach of mains electricity, it was difficult for RWE to find a suitable electronic alternative for the sites.

AquaMaster meters from ABB provided the solution. Fitted with their own battery power supply, AquaMaster flowmeters could be installed in locations where no mains supply was available.

Whenever RWE maintenance engineers find that a mechanical meter has failed, they now replace it with an AquaMaster as standard. With a measurement accuracy of ±0.5% over a turndown range of 1000:1, the AquaMaster can deliver accurate measurement even at extremely low flow rates, compared with their mechanical counterparts, which can only offer an accuracy of ±2%.

In addition, ABB has now become RWE Power's supplier of meters monitoring pumping stations in mines. In this case, accessing mains power is not an issue and RWE has opted for ABB's COPA XE compact electromagnetic flowmeters.

Erosive particles in the untreated mine water has led to frequent maintenance as sand in the water attacked and eroded the mechanical meters. The company initially tested 11 COPA XE units in its mines for nine months. It has now ordered a further 35 instruments.