Electricity and Control June 2022

MEASUREMENT + INSTRUMENTATION

Simple maintenance Analysers require specialised enclosures to protect the del icate mechanisms from the harsh surrounding environ ment. The J22 gas analyser has a robust enclosure, com bined with improved isolation and enclosure heating, which allow for it to be deployed in wet and cold climate zones. Whenever maintenance is required, analysers can be highly complex or difficult to take apart, and extensive ad justments are needed during

Summary Ensuring the reliable and safe operation of natural gas pipelines and other petrochemical systems requires the prevention of internal corrosion – which is caused largely by condensation in conjunction with other contaminants. In cases where the water content is critical, operators have to date had to rely on electrochemical methods, but the results are often inadequate. In contrast, TDLAS analysers enable a high degree of accuracy and offer user friendly interfaces, plus they deliver measurement values on a continuous basis at intervals of just a few seconds. That means users can determine at any time if the gas quality specification is being met or if corrective measures must be initiated. Furthermore, users can monitor the instrument continuously by means of the diagnostic data. This provides for quick detection of gas contaminants and rapid implementation of the measures needed to rectify the problem. With improved connectivity, users can access the analyser from virtually anywhere. □ acids and caustic solutions, drinking, cooling and wastewater, groundwater, raw water, and aggressive or salty solutions. But it is unsuitable for oil (which lacks conductivity). The MIK is housed in polyvinylidene fluoride (PVDF) and the electrodes in contact with the medium are made of tantalum. Both materials have proven to be totally chemically resistant. With the directly mounted transmit ter in stainless steel housing, the device forms a com pact and robust unit, ideal for fitting inside cramped con trol cabinets. It allows detection of small dosage amounts from 10 ml/min. The device operates according to the principle of electromagnetic measurement – Faraday’s law of magnetic induction – where a voltage is induced in a conductor moving through a magnetic field. The electrically conductive measuring agent acts as the moved conductor. The voltage induced in the measuring agent is proportional to the flow velocity and therefore presents a value for the volumetric flow. The flow rate is calculated on the cross-sectional area of the pipe. The measurement is dependent on the process liquid and its material properties, such as density, viscosity and temperature. The device may be equipped with a switch, frequency or analogue output. With an analogue 4-20 mA signal (or optional pulse output) the MIK communicates the measured values continuously to the users’ process control system. Thus it allows for immediate response to the latest process For more information visit: www.endress.com

The TDLAS analyser is designed with robust internal components protected by a solid enclosure, making it unnecessary to install the analyser in a protected space.

reassembly. Some analysers require matched component sets, which forces users to purchase costly spare parts kits or send the analyser back to the factory. This can impact the availability of measurements at critical transfer points. The J22’s modular design and easy-to-remove gas sample cells enable simple maintenance without long downtimes, even if the instrument is difficult to access.

MEASUREMENT + INSTRUMENTATION : PRODUCTS + SERVICES Phosphate precipitation in wastewater treatment plants

The problem of phosphate precipitation in wastewater treatment plants is typically addressed by adding iron (III) chloride (FeCl 3 ) into the aeration basin. The phosphates dissolved in excess wastewater are chemically mixed with sludge flocculants and transferred with sludge to the sludge treatment stage. This process reduces phosphate concentration in waterways and serves to minimise the potential for abnormal algae growth and the detrimental effect on the aquatic ecosystem. However, because an overdose of iron (III) chloride results in severely polluted water – toxic to people as well as the environment, a completely dependable method of process monitoring is needed. Kobold was tasked to provide a solution. The ideal would be continuous flow measurement of the dosing chemical with a direct data connection to the process control system, which would guarantee water treatment plant owners maximum safety. It would ensure that possible errors were discovered in good time, not

Developed for use in wastewater treatment plants, the Kobold MIK flowmeter is designed to control dosage of iron chloride.

only after the event (during sample taking) when it is too late to rectify them. The Kobold MIK magnetic inductive flowmeter was developed specifically for this application and provides an optimal and economical solution for safe dosage of FeCl 3 . The unit has already proven itself in service, specifically for electric conductivity liquids,

20 Electricity + Control JUNE 2022