Watertube boiler, data reporting save research facility time and trouble
The director of facilities, Rock Morille, and the project engineer, James Kisiel, wanted the new feedback technology in addition to the other "watertube vs. firetube" benefits. "This was the best and most efficient way for us to get the campus ‘usage trends' information that we must track in order to comply with regulatory standards," said Morille.
Being in Houston, Baylor has to contend with government regulatory agencies that impose greater restrictions on it. Kisiel commented, "One of the great benefits of our particular brand of watertube boiler is that it allows you to add sensing and measuring devices and record critical operating information which is then seen in the software package that organizes and displays the other measured points."
The monitoring system feeds back gas-related data in a number of forms (focusing the operator's attention on total system performance). There is data on high and low gas pressure, how long the boilers actually run in high-fire or low-fire, fluctuations in flue gas temperatures, etc. This feedback from the monitoring system can verify that a plant is in compliance."
Full Feedback Plus ‘Black Box' ExpertiseJoe Regini, the supervisor of the Baylor Central Plant, described how their brand-new feedback system has already helped solve a problem, eliminating the need for a costly service call, "Recently, I had a flame signal failure. It is supposed to read five volts on the flame signal, but it didn't."
The flame signal failure showed up on the boiler monitoring system's day-by-day, 31-day report of data from the various signal, pressure, temperature, conductivity, and SCF monitors. The "31 Days Data" screen shows the voltage of the flame signal. Regini was puzzled, "The boilers were operating perfectly, but I could not get a flame signal." With the boiler monitoring system, the customer has a choice, he can diagnose a problem, himself, or, he can call the boiler manufacturer, who receives more complex diagnostic data - the "black box" information in the four seconds before shutdown.
Regini decided to call the manufacturer for a diagnosis. The manufacturer identified the flame signal connections as the source of the problem. The connections are in a little plug, like a headphone plug, and they were loose on the controller. Regini continues, "Once I plugged them completely in, they were fine."
Why Not Stick With Old Technology?Baylor's decision to switch to the newer watertube technology evolved over time. Over the years, as Baylor expanded, it increased its firetube boiler capacity to 21 bhp. The 21st-century physical plant that Baylor is striving to complete had to confront redundancy, capacity, regulatory, and space issues. Morille and Kisiel evaluated conventional systems as well as systems differing from standard installations in the United States order to find the best fit for the campus.
Regini felt the old firetube boilers weren't meeting Baylor's needs, "The firetubes take a long time to bring up steam pressure. If you start one from cold, it would take you at least an hour to an hour and a half to bring it up to steam pressure. We wanted an on-demand steam generator and we needed redundancy built into our system."
To meet its on-demand steam needs, Baylor decided to switch to watertube boilers. Regini explained, "They only hold about 78 gallons of water, each. So instead of heating a firetube boiler that holds thousands of gallons of water that I have to keep bubbling and hot all the time, I'm heating a smaller surface area and I'm directly changing the water into steam at a much more efficient rate. I'm running, virtually, a one-pass system. Water is coming in the bottom and coming out as steam at the top. So it's not sitting there simmering like a pot on the stove."
At the time of their switch from firetube to watertube, Baylor replaced 2,100 bhp of firetube boiler capacity with seven 300-bhp Miura watertube boilers - retaining one 600-bhp firetube boiler.ES