Thermal flow meter reduces maintenance costs at water plants

Fluid Components International’s (FCI) robust ST80 Thermal Flow Meter Series provides precision air/gas measurement so that technicians in the water sector can optimise their ozone disinfection process without the use of chlorine chemicals whilst almost eliminating the need for meter maintenance. They offer high performance mass flow measurement and proven thermal dispersion technology at an economical price.  Operators of the ST80 Series Flow Meters have no need for extra pressure and temperature sensors, flow computers, or other devices that are required with orifice plates, Venturis, Vortex shedding, and other volumetric meters.  The ST80 Flow Meter also requires virtually no maintenance so end-users enjoy low installed and low life-cycle costs. 

The ST80 Air/Gas Flow Meter Series, available in both insertion and inline configurations, is ideal for air or gas line flow measurements in a range of water treatment plant applications. The insertion style meter works over an extensive flow range of 0.25 to 1000 SFPS (0,07 to 305 NMPS) This device is factory calibrated and can provide a flow turndown range of 2:1 to 100:1; surpassing the capabilities of other flow meter technologies in variable demand flow processes.

Ozone is an unstable molecule that is easy to convert to oxygen. As an oxidising agent, it becomes a strong disinfectant that can be used in water treatment applications because it kills hazardous organisms in raw water supplies to make the water safe for human consumption.  There are a few different types of ozone water treatment, each with its own benefits and shortcomings.  

All ozone systems offer excellent disinfection capabilities while eliminating some of the chemical by-product issues created by water chlorination. These systems ensure that the treated water has no odours or after-taste.  Moreover, the efficiency and operational cost of ozone disinfection systems rely heavily on precise, dependable air/gas flow measurement in difficult conditions to operate efficiently.

FCI’s ST80 Flow Meter features integral temperature compensation enabling highly repeatable performance in a wide variety of process environments. This instrument has accuracy up to ±1% of reading with ±0.5% repeatability over various temperatures and pressures in line sizes starting from 2 inches (6 mm) and higher.  

This flow meter’s thermal dispersion flow sensor design is precisely engineered so it does not use any moving parts by utilising solid-state platinum RTD sensors that are precision matched and embedded in equal mass thermowells. The sensor has been designed so it needs almost no cleaning and is less prone to fouling than other flow measurement technologies in which there are concerns about gas streams laden with particulates.  

The rugged and reliable ST80 Flow Meter is available optionally with remote mounting capabilities in situations where space is at a premium or the measurement point is difficult to access.  The remote mount transmitter, with local indication of flow, temperature and totalised flow as an optional extra, can be deployed up to 1,000 feet ( or 300 meters) away from the flow sensor located within the process piping.

These instruments include scalable dual 4-20mA outputs as standard; these are user assignable according to flow rate or temperature. Outputs are user programmable to full flow range or subsets of full flow range.  They are also isolated and have fault indication per NAMUR NE43 guidelines, and they user selectable for high (>21.0 mA) or low (<3.6 mA).  Standard digital outputs available are HART (v7 compliant), Modbus RS-485 and USB Serial I/O.  Optional: digital outputs that can added are Foundation Fieldbus H1, PROFIBUS-PA, or PROFIBUS-DP

The ST80 Series Flow Meter has a wide array of international approvals and certificates: ATEX, CE, CPA, CRN, FMc, FM, EAC/TR CU, EQM/ECAS, IECEx, NEPSI, SIL (IEC 61508), UKCA (UKEX).