Measuring Coal Powder Levels
When Nothing Else Will Work
Coal-fired power plants are commonplace around the
world. In order for these power generating stations
to create huge amounts of electricity the turbines
need to be feed with steam and the steam created by
boilers that are fired by … yep, coal. But
coal as it comes from the mining operations is not
what is fed to the burners. First it is ground
or pulverized into powder. It is not unusual
for the coal powder to be stored in silos awaiting
the demand for it to be fed to the burners. The
inventory of coal powder in these silos needs to be
monitored to allow for efficient operation of the power
plant.
So, how do we monitor the inventory of coal powder
in a silo? Not easily. In one typical application
the power plant personnel found that the only technology
that would work reliably is the modern smart weight & cable
system fro Monitor Technologies LLC, the SiloPatrol® SE.
Anhui
Tongling power plant in Anhui province in China had
tried almost ever technology possible to get a reliable
level measurement in their 5 coal powder silos. Radar,
ultrasonic and others were tried, but none worked reliably. It
wasn’t until Beijing Conasen walked in and proposed
that the Tongling plant use the SiloPatrol SE smart
cable-based inventory monitoring system that the power
plant personnel found a reliable solution.
Mr. William Yuan, sales manager for Beijing Conasen
indicates that the power plant tried many major brands
of ultrasonic, radar, and other technologies but that
due to good relations with the Tongling plant personnel
he was able to sell three SiloPatrol SE model SMU sensors
and an HMI operator interface to them. The units
were installed by plant personnel. Because of
the heavy amount of coal dust in the silos an air purge
using dry compressed air was used. The SiloPatrol
sensor incorporates the patent-pending use of Hall-effect
sensor technology, a split-compartment enclosure, microcontroller,
redundant optics and many other valuable features and
technology to ensure reliable measurement even in challenging
dust applications like coal powder.
The SiloPatrol SE system has been working reliably
and the plant has since purchased two additional sensors
and connected them into the same HMI operator interface. This
same sensor technology is working reliably at other
coal-fired power stations in China as well.
Monitor Technologies LLC is a pioneering supplier of level measurement instrumentation,
solids flow monitors, particle emission monitors and aeration devices for the
worldwide powder and bulk solids markets. The experience and market knowledge
gained over 50 years of business has earned Monitor a reputation for providing
high quality and reliable product solutions backed with trusted customer service.
Monitor is located in Elburn Illinois.
The
SafePoint rotary paddle level switch with a self-validating design
detects material presence plus continuously monitors its own ability
to function. The analysis includes sensor health and system power
failure, which makes the SafePoint truly “fail-safe”.
The SafePoint incorporates patented use of Hall-Effect technology,
dual outputs to indicate both material presence and unit health,
and microcontroller technology to continuously protect bulk solids
processing and storage from the consequences of unknown sensor
failure by providing immediate indication of a sensor failure
and confirmation of proper operation.
Other practical features of the SafePoint include rugged construction,
motor shut-off when paddle becomes impeded to maximize motor life, twist On/Off
cover for bolt free removal, and local status indicating light (except hazardous
location models)
A practical application for the SafePoint would be to use this "true"
fail-safe product if undetected sensor failure could result in a
catastrophic process problem.
