Dynasonics Flowmeters Help Save Water

Dynasonics ultrasonic flowmeters have been used in an application where open ditch irrigation has been replaced by a closed pipe system and precise flow control via wireless communications. This system was employed by the Montezuma Valley Irrigation Company (MVIC) in Cortez, Colorado, to save water in the arid region. As much as 60 per cent of the water that enters an open ditch irrigation canal is wasted via evaporation, seepage and losses at the end of the canal.

By replacing five miles of open irrigation ditches with closed polyethylene pipe and flow control, MVIC is saving 1,000 acre-feet of water per year. Each branch turnout from the main header to a farm has a Dynasonics ultrasonic flowmeter and two butterfly valves. The meter measures the amount of water passing through the turnout. The first butterfly valve is controlled by the MVIC and is used to set flows according to the number of shares of water allocated to that particular farmer.

The second butterfly valve can be used by an owner to shut off or reduce water volume. Flow control and measurement is implemented via a wireless supervisory control and data acquisition (SCADA) system. The SCADA system consists of a telemetry receiver and master control centre in the main office connected to field equipment via a wireless data link. Each flowmeter is either solar or battery powered, providing savings by eliminating power wiring.

This feature not only saved on installation, but will also provide ongoing savings in the form of lower energy use. The key component of each branch turnout is the flowmeter. The closed pipe network project has been successful and the US Bureau of Reclamation is providing stimulus grants to the MVIC for construction of a second similar seven-mile pipeline project.

Sierra Mass Flowmeters Are GHG Certified

Sierra Instruments has introduced a line of mass flowmeters certified by Sierra for greenhouse gas (GHG) reporting. The company said that all Sierra GHG meters now conform to the new EPA rule (40 CFR Part 98), which mandates that as of 2 January 2010, companies in the US that emit more than 25,000 tons/year of CO2 equivalent must report GHG emissions.

Sierra claimed its GHG certified mass flowmeters provide an economical way to totalise methane or natural gas burned, enabling the calculation of CO2-equivalent emissions. Sierra has experience in producing accurate and repeatable mass flowmeters for methane (CH4) as well as N20, SF6, HFCs, PFCs and CO2. The three GHG certified thermal mass flowmeters are the Boiler-Trak, model 640S and model 780S.

Sierra Boiler-Trak is a thermal mass flowmeter designed for stationary combustion applications (commercial boilers, kilns and heaters), which are among the largest emitters of CO2. Sierra model 640S has been optimised for landfill gas, the second largest source of CO2. Landfill gas is very humid, at low pressure (20-40mbar/g) and about 40C to 60C when it leaves the landfill.

The 640S has 100:1 turndown, no moving parts, and generates nominal pressure drop across the immersible sensor probe, and so it is ideal for this application, Sierra said. The Sierra model 780S was designed for gas and electricity producers, the third largest category of CO2 emitters. This flowmeter is routinely used by gas and power plants to measure methane to compressors, pre-heaters, boilers and other process equipment.

Aalborg Releases Direct-Reading Flowmeters

Aalborg Instruments has introduced direct-reading scales for Models P, S and T flowmeters. Direct-reading flow-tube scales are designed for a specific gas or liquid at a given temperature and pressure, valid only for the associated units of flow. Flow rates for a specified set of parameters are clearly indicated in specific engineering units, such as ml/min or scfh.

Using correlating tables and graphs to determine flow rates is no longer necessary. NIST-traceably calibrated for specific liquids and gases, these units are ideal for OEM applications and processing industries. Direct-reading scales are available for argon, carbon dioxide, helium, hydrogen, hydrogen chloride, methane, nitrous oxide, oxygen and propane.

Turbine Flowmeters Measure Aggressive Chemicals

The Titan 800 Series turbine flowmeters are low-cost, non-metallic meters, ideal for measuring aggressive chemicals including ultra-pure water. The standard connections will accept 8mm or 12mm hose sizes and the electronic output from a Hall effect sensor gives NPN or PNP pulses for a remote counter, offering 0.1 per cent repeatability over a flow range of 30:1.

With a PVDF plastic construction, the standard unit operates to 60C and 10 bar, and two built-in LEDs indicate power and the output pulse rate. A direct flow switch output is available, for low flow or cooling flow failure alarms, as are units suitable for high-temperature 125C operation. With the optional six-point water calibration, the Titan 800 series offers 1-2 per cent flow accuracy. The flow ranges available cover from 0.05-15 litres/min.

Flowmeters Monitor Waste Water

The Wells Sanitary District waste water treatment facility has installed four Optiflux electromagnetic flowmeters to monitor the flow of sludge at the treatment plant. The newly refurbished plant on the southern coast of Maine, USA treats up to 7.5 million litres of waste water per day. Engineering consultants redesigned many of the systems and processes at the facility and replaced all the existing electromagnetic flowmeters with Krohne's Optiflux instruments.

The Optiflux incorporates advanced measurement technology, which is highly accurate even when measuring substances with a high bubble or solid content or where there is turbulent flow. The flowmeters installed at Wells Sanitary District are being used to measure sludge recirculation and monitor the amount of effluent that is treated.

In the sludge recirculation area, which forms part of the of the facility's in-line waste activated sludge process, two Optiflux flowmeters are being used to measure the throughput of sludge, which is calculated per minute and per day. Another flowmeter is installed to measure the flow of sludge being removed from the system. The fourth Optiflux is used in the treated effluent area to measure the flow of treated water that flows through the facility.

Dennis Thayler, Superintendent at Wells Sanitary District, said: 'Many people don't realise that these meters operate 24/7, under demanding conditions, so they need to offer superior performance and reliability'. 'The use of accurate and reliable meters in this environment cannot be overstated'. 'Flowmeters are essential to the overall process here - and at any treatment facility, for that matter'.

The Wells Sanitary District now meets all safety standards required by the US environmental protection Agency (EPA) and Maine's Department of Environmental Protection. The Optiflux magmeter provides precise measurement across a wide and demanding range of applications. It can achieve an industry-leading accuracy of 0.15% and reproducibility of 0.06%, even when measuring materials with high solid content or that have turbulent flow.