Green energy generation often uses steam as a method of generating energy. Biomass, concentrated solar power, geothermal energy, and other forms of energy utilise this method. Knowing the balance of water and steam contained within the boiler is essential for safe and efficient running of the entire plant.
Delta Mobrey has years of experience in monitoring the levels of steam and water so that boilers operate safely. Hydrastep has been designed specifically to monitor boiler levels, irrespective of industry, in the simplest and most reliable manner. This makes Hydrastep a compelling option for steam based plants seeking streamlined and efficient operations. Hydrastep gives the confidence of knowing that water tub boilers are protected from low water levels and their turbines are protected from water run over.
The Combustion Engineering Association, CEA, asked Delta Mobrey to contribute to their most recent guidance document, BG11, because of the reputation that Hydrastep has earned over the years. While BG11 gives guidance on the design, operation and maintenance practices relevant to the UK, the practices highlighted are of benefit globally, as their basic premise is safety and efficient boiler operation. BG11 includes guidance on control systems and instrumentation of the boiler systems. The guide explains that maintaining the correct boiler drum level is critical. If the water level is too low, there is a risk of damage to the boiler drum and tubes, as well as overheating. If the level is too high, water can reach and damage the superheaters, or eventually the turbines. BG11 states that “there are many technologies available to measure and control steam drum levels and triple redundancy whilst mixing technologies is becoming commonplace.” The guide explains the need for a usual indication of the drum level and that is a requirement of both BS EN 12952 and the ASME boiler and pressure vessel code. Traditionally, sight glasses were used, but these are difficult to read and often require maintenance. BG11 cites Hydrastep as giving a clear display, both locally at the drum and in the control room, and is the preferred solution for steam drum level indication (P26).
Hydrastep was originally developed with the UK’s CEGB. Using conductivity probes positioned along a vertical water column gives a highly reliable method to differentiate between steam and water. The level display can be repeated in the control room and is immediately visible to operators without having to look at monitors.
Alarms of trips can be assigned to chosen levels. The dual redundant design means that even with an internal fault, the Hydrastep will continue to give a drum level indication. BG11 refers to Hydrastep as having exceptional reliability because of this (p. 26).
Delta Mobrey’s Hydrastep is being used in several green energy plants within the UK and further afield in Europe. Hydrastep is becoming the choice of plant operators to ensure the safety of the plant and personnel.
About Delta Mobrey
For more than 100 years, Delta Mobrey Limited has been a world-leading specialist in the design and manufacture of quality process instrumentation for the measurement and control of fluids and gases in all industrial plant and equipment.
Trusted quality – proven value: quality and reliability have always formed the cornerstone of our success, recognised by industry with international approvals covering every aspect of our manufacturing and product portfolio, together with certifications spanning all areas of hazardous and regulated environments.
Global team – local support: as a global organisation, Delta Mobrey is totally committed to delivering the best possible customer service and technical support, ensuring a lifetime value of ownership, together with a flexible and responsive approach to meet our customers’ individual demands.
