Highway rest area (R&R) is a place where travellers can take a break before resuming their journeys. Our Technical Team has been on the go last week to perform flow verification services at several rest area (R&R) sewage treatment plants (STP) along the highways running through the west coast of Peninsular Malaysia.
The verification service is to ensure the flow meters are working under optimal operating conditions and installation method. Regular flow verification with consistent intervals and record keeping will ensure that flow discharge measurements are always accurate and reliable.
Requirements
- Instrument: 9 x Open channel flowmeters; 1 x electromagnetic flowmeter at 10 different STP
- Medium: STP effluent
- Installation configurations:
- Open channel:
- 2” parshall flume
- Standard 60°/ 90° v-notch weir
- Non-standard sizing v-notch weir
- Electromagnetic flow meter:
- 4” pipe size; wall thickness: 3mm
- Open channel:
- Services:
- To ensure the flow rates are accurate comparing against the parshall flume discharge table
- To ensure the flow rates are accurate comparing against the standard v-notch weir discharge table and the standard Kindsvater-Shen equation
- To ensure the flow meters are measuring accurately under optimal operating conditions and installation method
Solutions
- For the parshall flume installations, the throat width size, installation height and the water level are measured. The flow rate is calculated using the formula provided by the 2” parshall flume discharge table.
- For the 60°/ 90° v-notch weir installations, the flow rate is calculated using the formula provided by the v-notch discharge table.
- For non-standard sizing v-notch weir, the flow rate is calculated using the Kindsvater-Shen equation
- Open channel sensor height and position are corrected if it encounters sensor deadband or beam angle issues
- Recommendations:
- Use corrugated PVC flexible hose to protect electrical wiring from moisture
- Change non-standard sizing v-notch weir to a standard 60°/ 90° weir for better accuracy
- This verification lasts for one (1) year.
- The findings and recommendations for each STP are elaborated in details and documented in 10 individual I-SYSTEM service reports for auditing and documentation purposes.
