PROCESS EQUIPMENT UPDATE
Presser explains that electric boilers use the conductive and resistive properties of water to carry electric current and generate steam. An AC current flows from an electrode of one phase to ground using the water as a conductor. Since chemicals in the water provide conductivity, the current flow generates heat directly in the water itself. Te more current (amps) that flows, the more heat (BTUs) is generated, and the more steam produced. As an example, in Acme’s CEJS high
voltage electrode steam boiler, almost 100% of the electrical energy is converted into heat with no stack or heat transfer losses. Te electrodes of the jet type electrode steam boiler are vertically mounted around the inside of the pressure vessel. Tis enables the unit to produce maximum amounts of steam in a minimum amount of floor space, with boiler capacity from 6MW to 52MW. Operating at existing distribution voltages, 4.16 to 25KV with up to 99.9% efficiency, the boiler can produce up to 170,000 pounds of steam per hour. With pressure ratings from 105 psig to 500 psig, the boilers are designed to ASME Section 1, and are certified, registered pressure vessels at the location of the boiler. “With the jet type electrode boilers,
there are no combustion hazards because there are no flames, fumes, fuel lines or storage tanks, which minimises the risk of explosions and fires,” says Presser. In
case of an electrical short, the breaker that protects the high voltage circuit trips in a matter of milliseconds, protecting the boiler and the electrical network. Tere is no chance of electrical mishap or fire from the boiler. Since the design does not rely on combustion, it does not create emissions that would endanger the operator or environment. In addition, the design eliminates many environmental issues associated with fuel burning boilers such as fuel fumes, fly ash, and large obtrusive exhaust stacks.
SAFETY FIRST Te approach resolves safety issues related to potentially excessive heat accumulation with the system as well. Low water protection is absolute since the absence of water prevents current from flowing and the electrode boiler from producing steam. Unlike conventional electric boilers or fossil fuel boilers, nothing in the electrode boiler is at a higher temperature than the water itself. Tis prevents the risk of dangerous heat build up in the boiler, electrodes, and other important components even if scaling should occur, and thermal shock is eliminated. “Electric boilers, and specifically the
electrode units, are inherently the safest boiler design today. Tese units do not need an operator because if anything goes wrong, the breaker trips, preventing further escalation of the issue,” explains Presser.
The latest electrode boilers reduce the risk of explosions and noxious emissions
Te electric boilers also improve safety
by reducing industrial noise, which is an OSHA regulated issue. Under OSHA’s Noise Standard, the employer must lower noise exposure through engineering controls, administrative controls, or hearing protection devices (HPDs) to attenuate the occupational noise received by the employee’s ears to within levels specified. In this regard, the electric units are
also exceptionally quiet compared to fuel fired boilers. “Unlike gas-powered burners that throttle like turbine engines almost continually, electric boilers keep operational noise levels down,” says Presser. “Because the loudest boiler component is a circulating pump motor, you can have a conversation next to one without the need to elevate your voice.”
Modern boilers are safer, more energy-efficient alternatives to gas burning units
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Although the safety of the electrode units is superior, there are also benefits in terms of reliability and maintenance. Te absence of excessive temperatures and burnout assures longer operating life. Te boilers have a minimum number of components and electrical controls. With no fuel residues, along with fewer parts and simple control systems, cleaning and maintenance requirements are reduced, and reliability is enhanced. Processors worldwide have long sought to improve safety, yet options have been limited. Now, as safer, more energy-efficient alternatives become more widely available in the form of state-of-the-art electrode boilers, companies can protect their people and processes more completely while minimising required maintenance.
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