Reactor blowout sidelines Orlando's waste-to-energy hopesMar 15 - McClatchy-Tribune Regional News - Mark Schlueb Orlando Sentinel
After Orlando invested $8.5 million and years of its workers' labor, an experimental energy reactor at a city sewage treatment plant suffered a massive, violent blowout. The incident, which mangled a steel pressure-relief apparatus and blew the vents out of the city building, has sidelined a plant that had drawn international attention because of its promise to convert sewage sludge into electricity. "There was significant damage to the building," Public Works Director Rick Howard said. "Given timing, somebody could have been hurt." No one was injured because no one was standing nearby at the time. The blow-out happened last summer, but city officials did not publicly acknowledge the mishap until asked by a reporter. The reactor has sat idle ever since, as the city's private-sector partner tries to raise the capital to build a new one. The reactor isn't something you would find in other sewage treatment plants. Orlando's normal treatment process uses microorganisms that feed on the waste from the city's toilets and sinks. It produces treated wastewater that's clean enough to use for irrigation on golf courses and lawns. But another byproduct of the treatment process is harder to deal with. The bacteria reproduce so much as they eat that the city is left with tons of smelly, mud-like piles of microorganisms. That's sludge, and it never stops coming. For years, the city has spread its sludge on fields and pastures. But wet weather and the threat of tighter environmental regulations have Orlando and other utilities looking for other options. In 2007, Orlando signed an agreement with a Palm Beach County company, SuperWater Solutions Inc., to jointly develop a process for getting rid of the sludge using a process called "supercritical water oxidation." City officials are convinced the technology is their best hope for replacing the costly need to dump sludge on pasture land. They built the test reactor at the city's Iron Bridge treatment plant near the University of Central Florida, investing $8.5 million of utility money in the project over the years. The reactor subjects the sludge to extreme pressure and temperature, destroying all organic matter and leaving water and carbon dioxide behind. The process also releases heat that can be harnessed to produce electricity. Other companies also are experimenting with the process, but so far no company has successfully used the technology to treat sewage sludge on a large scale. Technical hurdles have stood in the way The reaction is notoriously hard to control. Temperature and pressure levels must be monitored and adjusted constantly to compensate for sudden fluctuations caused by inconsistent energy levels in the sludge. "Things can get out of hand quickly," Howard said. "We're trying to control a process that is, by its nature, volatile and hard to control." In July, something went wrong. An expansion tank meant to absorb excess pressure suffered a blowout, releasing a powerful, high-pressure shockwave into the surrounding building. The blowout knocked out vents and left the building's metal walls warped and bent. SuperWater Solutions CEO Don Morgan said the accident was caused by a failed gasket. City officials say there was no explosion and no fire, but the mishap left the reactor unusable. City Hall would not release photographs of the damaged reactor, saying it might reveal trade secrets. A spokeswoman said neither the public nor city commissioners were informed of the blowout because there were no injuries. "In the development process, this is the kind of setback you're going to have along the way," Heather Fagan said. Even so, it is a blow to the years-long effort. In 2012, city officials and SuperWater Solutions were so confident they had perfected the process that the City Council voted to turn over the test reactor to the company. SuperWater Solutions plans to market the process on a commercial scale, building and selling reactors to utilities elsewhere. As part of that agreement, the city is supposed to be paid royalties of $2.60 for every ton of waste the company treats at plants it hopes to build around the world, a deal that at the time was estimated to be worth $62 million to the city over 20 years. The deal also required SuperWater Solutions to pay the city $1 million for the test reactor. The first $200,000 payment, which was due in January, has not been made. Morgan said the company plans to build a new reactor at the Orlando treatment plant, incorporating what's been learned since the original was built. The new reactor has been designed, Morgan said, and company executives are awaiting word from potential investors. "We know the technology works," Morgan said. "The improvements and developments we've realized over the last several months have us very enthusiastic for our plans going forward." Orlando officials said that for safety reasons, the new reactor would be located elsewhere on the property, away from city workers. They want the company to succeed -- not because of the potential profit for the city, but because it would solve their sludge problem. "We still see it as the ultimate option," wastewater division manager Vic Godlewski said. "It has so much potential." mschlueb@tribune.com, 407-420-5417 or Twitter @MarkSchlueb http://www.energycentral.com/functional/news/news_detail.cfm?did=31845171& |