UK Water Utilities and industries discharging effluent to the environment are now obliged to meet regulatory requirements for monitoring. In England and Wales, these require discharges to be monitored to a given uncertainty (+8% total daily flow) and all installations inspected every 5 years under the MCERTS Monitoring Certification Scheme.
For many installations, meeting these requirements with traditional open channel structures is difficult. Closed pipe flowmeters can give significant benefits: lower installation costs / maintenance requirements; better measurement at low flows, small discharges (now under the Regulations) and on modern processes (e.g. package plants where inlets / outlets are enclosed).
Closed pipe flowmeters offer good accuracy but performance in influenced by installation conditions, e.g. effect of upstream fittings on velocity profiles. Manufacturers recommend installation conditions which are difficult / expensive to achieve and give accuracy above that required by Regulators. Also, most performance data is from clean not wastewater.
A Good Practice Guide for closed pipe flowmeters discharge monitoring will address: meter selection; sizing; installation; effect of solids on performance; O&M and demonstrating continued performance over time.
Capex savings through reduced installation costs.
- Utilities and industrial companies will be able to meet their regulatory obligations for discharge monitoring with increased confidence, particularly for small discharges.
- More effective purchasing on a wider range of lower cost flowmeters giving:
- Opex savings through reduced long term certification and O&M costs.