Friday, May 16, 2008

'Biosolids' plant takes stink out of sludge
Pellets to be used for fertilizer
By MICHAEL CASS • Staff Writer • May 4, 2008

The things you flush down your toilet could feed someone's lawn before summer's over.
Metro Water Services is running the final tests before it opens a new waste-water treatment facility on Second Avenue North. The $125 million Central Biosolids Facility will convert waste water produced by Metro residents and businesses into tiny pellets that can be used as fertilizer.


About 70 tons of pellets, known as "biosolids," will replace the 350 tons of treated sludge the city has been sending off to landfills every day. The stench that has sometimes annoyed residents of nearby Germantown and Salemtown also should be eliminated, Metro officials said. The city spent $10 million on odor control.
"Salemtown and Germantown continue to develop, so we had to do something," said Ron Taylor, chief engineer for the water department's operations division.
"To go from having to send all that material to landfills and sending a lot of trucks through developing neighborhoods to a point where we'll cut the trucks by 75 percent, that is a transformation."
But the biosolids project still makes some people queasy.
Some environmental activists say Metro is essentially taking sludge that would go to landfills and putting it on soil, where it could hurt animals and people.
" 'Biosolids' is just a pretty name the industry gives sludge," said Sherry Force, who runs a recycling and environmental awareness program at Granbery Elementary School. "We should continue to landfill it until we find a safe way to dispose of it.
"These people do not know what's in this material at any given time, yet they've sanctioned it to be spread out on agricultural fields."
Taylor said the Metro treatment process will eliminate disease-causing pathogens found in the sludge, however, and produce a safe, nutrient-rich class of pellets. The process meets the U.S. Environmental Protection Agency's standards for reuse of waste water.
But the EPA's blessing doesn't mean much to Force or fellow activist Bruce Wood.
"Maybe the federal government lets us get away with it, but they let us pollute the Cumberland River, too," said Wood, who leads a Nashville environmental and public health advocacy group called BURNT.
More sewage processed
The number of Metro sewer customers has increased about 15 percent in the past seven years, Water Services Director Scott Potter said at a Metro Council budget hearing last month. Taylor said Metro has been sending about 100,000 tons of sludge a year to landfills at a cost of about $3 million annually.
That will change under the biosolids process, which will take the residual sludge produced by the older waste-water treatment process — the smelly gunk now going to landfills — and break it down further.
The new facility will thicken the residual sludge to start removing water and use anaerobic bacteria — bacteria that don't need oxygen — to reduce pathogens and decompose the sludge. That part of the process, which takes place in large buildings called "digesters," produces methane gas.
The digested sludge then will go to one of five centrifuges, which will "dewater" it to remove excess liquid. Finally, it will go through a heat-drying system, powered by the methane gas from the digesters, to evaporate the remaining water, destroy the remaining pathogens and produce the biosolids.
The pellets will be heated to 200 degrees Fahrenheit when the process is over.
Metro has contracted with Arkansas-based Mannco Fertilizer Co. to market 25,000 to 30,000 tons of pellets a year, according to the company's Web site.
"Mannco has successfully developed markets for use on row crops, golf courses, horticulture and turf grass needs," the Web site says.
Jeff Gossage, Metro's purchasing director, said Friday that the marketing contract had been awarded but did not call back with details.
Greenway planned
Metro also is planning to build a greenway near the biosolids facility, said Shain Dennison, greenways director for Metro Parks. Construction could start this summer on the 1.5-mile stretch, which would be part of a greenway system connecting downtown to MetroCenter and would feature a spur to Germantown's Morgan Park.
"It's going to be a better thing when they get everything done," said Salemtown resident and blogger Mike Byrd, who has complained about the smell coming from the waste-water treatment plant in the past. "All the dominoes seem to be falling into place. … It's a great thing for Salemtown."
Metro also has built a smaller, $25 million biosolids facility at its Dry Creek waste-water treatment plant in the Rivergate area. The Dry Creek plant opened in 1961, three years after the Central plant opened north of downtown.

http://tennessean.com/apps/pbcs.dll/article?AID=/20080504/NEWS01/805040428/-1/ARCHIVE01

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Another Sludge Pelletizer Fire - Honolulu


http://the.honoluluadvertiser.com/article/2007/Jul/15/ln/FP707150378.html

Posted on: Sunday, July 15, 2007

Oahu sewage upgrades fall behind

Photo gallery: Sand Island wastewater treatment plantBy Johnny BrannonAdvertiser Staff WriterHawaii news photo - The Honolulu AdvertiserAt the Sand Island Wastewater Treatment Plant, Tim Robinson stands in front of a key part of the facility, an egg-shaped "digester" that is used as part of the sludge recycling process.Photos by JEFF WIDENER The Honolulu Advertiser
Hawaii news photo - The Honolulu AdvertiserSand Island sewage plant employees Allen Perry, back, and Silvestre Ulep walk along a large holding tank for raw, untreated sewage.

Growing pressure to reduce pollution risks from O'ahu's sewage and to decrease the amount of debris flowing into the island's main garbage dump, two costly projects that affect both situations remain hampered by problems.An important disinfection unit at the Sand Island Wastewater Treatment Plant is five years behind schedule and has cost $40 million more than the city's original $60 million estimate.The project — a first-of-its-kind application — is complete but has yet to begin a crucial yearlong period of continuous operation and testing to prove its effectiveness.Before that period concludes, the U.S. Environmental Protection Agency is expected to call for a major plant upgrade that could cost $800 million more and require major changes to the system of pumps and pipes that feeds into the disinfection unit.The second delayed project, a $38 million facility that converts dried sewage sludge from the Sand Island plant into organic fertilizer pellets, remains inoperable after it was damaged by an early-morning fire one month ago.In the meantime, about 36 tons of dried sludge "cake" are trucked to the city's Waimanalo Gulch dump each day as that site nears its permitted capacity. The dump's operating permit expires in less than a year, but the city hopes to expand the site and extend its operation.SOLUTIONS IN WORKSOfficials say problems with the sewage disinfection unit and fertilizer facility should be resolved within months, and that they are committed to making sure both projects are operated safely and efficiently.The disinfection unit — which zaps treated sewage with powerful banks of ultraviolet lamps to destroy pathogens — is now fully operational, said Allen Perry, city metro region wastewater superintendent.But a few lingering problems must be corrected, and some preliminary tests must be completed before the yearlong proving period begins, he said.The electric power that feeds the unit has sometimes spiked and damaged key parts or caused equipment to be shut down.That can't happen during the proving period, because the unit must operate without interruption — or face more delays, Perry said.A recent power fluctuation lasted only 10 seconds but destroyed 30 of the plant's 1,680 ultraviolet lamps, which cost nearly $300 each.Electricity to run the unit is expected to cost up to $9 million per year, so different light intensities and operating methods are being tested, city environmental services director Eric Takamura said.The light must be strong enough to disinfect the sewage properly without wasting electricity or wearing out lamps prematurely."We're trying to optimize the system to keep the costs down," Takamura said. "Every time we test under a different scenario, we have to wait for lab results to come back."Testing during the proving period will help determine whether the city must operate the unit continuously in the future, or only run it under certain weather and flow conditions that could push discharged effluent back toward O'ahu's shoreline.The unit is designed to handle up to 150 million gallons of sewage per day, and has five channels that can be opened or closed as there are peaks and lulls in the city's sewage flow.Each channel has 336 ultraviolet lamps that can be submerged in the sewage during operations.The unit was originally scheduled to be completed in July 2002 at a cost of under $60 million, but work was delayed by design changes and construction problems that increased the cost to $100 million.The fertilizer facility was to be completed by mid-2004 to help comply with a federal consent decree that requires the city to recycle some of its sewage sludge.But the project was delayed by community opposition and City Council concerns about possible health risks from use of the fertilizer pellets, which the city insists are safe.FIRE CAUSES DELAYSConstruction was completed in December, and production testing began early this year. But the fire that broke out before dawn on June 14 has pushed the schedule back again.The facility had been shut down for the night before the fire broke out, and the cause of the blaze remains under investigation, said site manager Kenny Huy of Synagro, a company that will operate the facility for the city.Repair work is on schedule and should be completed by the end of September, and insurance should cover the cost, which is still being estimated, Huy said.The company is awaiting final approval from the state Health Department to begin selling the fertilizer pellets, which also could be used in some city parks and golf courses.The fire mainly burned fiberglass odor-control ducts, insulation and plastic water pipes. The blaze also broke or melted several large windows and singed parts of the facility.But a key part of the facility — an egg-shaped "digester" 116 feet tall — was not damaged and remains operational.Officials expect that more than 90 percent of the dried sludge that now goes to the dump will be made into fertilizer pellets when the facility is fully operational.The project was recently named a 2007 project of the year by the Hawai'i chapter of the American Public Works Association.The city expects to hear sometime after October whether the EPA plans to require the sewage plant to upgrade from enhanced primary treatment to a more comprehensive process, called secondary treatment.The process breaks down the biological content of sewage more thoroughly, and is performed at most U.S. wastewater treatment plants.The Sand Island plant, and another at Honouliuli, have operated for years without secondary treatment, under special waivers from the EPA.The federal agency announced in March that the Honouliuli plant should be upgraded, which city officials estimate would cost $400 million. A similar decision is expected in October regarding Sand Island, and officials estimate an upgrade there could cost $800 million.Mayor Mufi Hannemann and other city officials contend the upgrades are not necessary because the plants discharge treated sewage effluent in deep water far offshore. Most plants that perform secondary treatment discharge into lakes, rivers or shallow coastal waters.http://the.honoluluadvertiser.com/article/2007/Jul/15/ln/FP707150378.html

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Thursday, May 15, 2008

Windsor City Blogspot writes about Prism-Berlie (Azurix) American Water Services Pellets

(and don't forget about the big fire that shut down the plant in Oct 2002)

http://windsorcityon.blogspot.com/2006_09_03_archive.html

"Windsor Biosolids Processing FacilityThe City of Windsor, Ont. contracted with Prism Berlie (now Azurix) to build, finance, own and operate a biosolids processing facility for 20 years. The facility was completed in the spring of 1999 and uses heat drying to convert sewage sludge (biosolids) from Windsor's two sewage treatment plants into marketable fertilizer pellets. The City is responsible for providing a minimum of 30,000 wet tonnes per year to Azurix. The company is responsible for transportation from the City plants, all facility operations, permits and marketing the pellets to end-users. The original capital cost of the project, financed by then-Prism Berlie, was $10 million."
So I decided to look into it since it was described as a $60 million deal over its life. That's big money in any league. I read a very interesting document prepared by the City describing the deal. One comment jumped out at me "The private company's incentive under BOOT [build, own, operate,transfer] is to make as much money as possible during its period of ownership." Ownership transfers to the City after 20 years.It appears that sludge smells. Not only smells but stinks, badly. Getting rid of sludge can also pay well if you do it right.
The odours from "the open method of stabilizing and then storing biosolids, sometimes for periods exceeding six months, have upset both domestic and industrial residents in the west end of Windsor." Council decided in 1997 to plan for a "more effective non-odorous method of stabilizing and recycling the biosolids from" the two pollution control plants. Moreover, as the Star reported "Michigan Democrat lawmakers don't want stinky, blood smeared trucks carrying biohazards and bodily waste -- including treated sewage sludge from Windsor -- rolling through Michigan streets. "After an extensive RFP proposal that is set out ad nauseum in the Administration Report, Prism-Berlie won the job with their technology. Of course it was picked since it was "state of the art" and would "operate with no offending odour." We in Windsor have to be the pace-setters right.
In an article I found, I saw that
"Azurix Corp is a holding company formed in 1998 with the majority of stock split evenly between Enron Corp and Marlin Water Trust. (Public shareholders own the rest. It is traded on the New York Stock Exchange, listed under the short form AZRX. Azurix companies are located around the world, among them Wessex Water Services Ltd. in the United Kingdom, and there are water treatment facilities in Argentina as well."
One of its "purchase in Ontario was Prism Berlie, which operates a state-of-the-art biosolid pelletizing plant in Windsor." In April 2001, Enron announced it would break up Azurix and sell its assets.
The contract was signed in 1997 to start, after construction, in 1999. There was a 2 year period when the former contract ended and the new plant was operating so a tender went out for hauling sludge to a landfill and Prism-Berlie won that tender at a price of $27 per ton. [Remember that number]The plant opened. I am not sure if someone confirmed that the plant met its specs at the time and was able to process all of the sludge. I believe that, in fact, the plant may not have done so and therefore some amount of sludge still had to be hauled away. That should be an easy figure to obtain.
Another interesting Star story in June 1999 said
"Windsor's much-vaunted high-tech and environmentally friendly solution to dealing with its sewage has, according to this story, turned into very expensive garbage. It cost city taxpayers $40 a tonne a few months ago to landfill city sewage. The $19-million state-of-the-art Prism-Berlie biosolids recycling plant which opened Thursday with much fanfare turns that sewage into $84 a tonne fetilizer pellets for commercial sale. The pellets, however, are being trucked straight to the landfill. Agriculture Canada still hasn't granted a licence so the pellets can be sold as fertilizer."
The Star reported that "The plant was plagued by fires following its March 1999 opening and closed in October 2002 when an explosion destroyed equipment, blew holes in walls and caused $5 million in damage." Obviously from that time until re-opening, sludge had to be shipped away. The Star reported that it was actually a good deal for the City since we were being charged $60 to send the sludge to the landfill and not paying the amount of $90 under the contract for the sludge to be processed.No matter the optimistic Administration reports to Council that set out the new opening dates (September 2003, then March 2005, then June 2005), it took around 4 years to rebuild the plant. During all of that time, sludge was hauled to landfills in Ontario and Michigan by Prism-Berlie at $60 per ton it appears.In going through this series of events, I had a number of questions:
Did anyone in the past confirm and can anyone confirm now that the old plant and now the new one meets specs and can process what it is supposed to process. Is the plant in compliance and what tests were run to prove it
If not, what will the City do about it?
During the period while the plant was operating, what percentage of the sludge was processed? For the balance, what happened to it. If it was shipped to a landfill, what price did the City pay---$27, $40, $60 or $90
During the 4 years after the explosion, did the City pay $60 for hauling and not $27 and if so, why? It was said that the city "saved" money....In fact, did the City pay out too much ["Shuttering the plant saved the city money. It's been paying $60 per ton of sludge to haul 2,500 tons of waste per month to Michigan for disposal in a landfill. It costs $90 per ton for the recycled process. "It's cheaper to put it in a landfill, but it's not environmentally viable or an appropriate thing to do," [Kit] Woods said."]
How was the $60 calculated and did it go out for tender?
Will the City get a plant of value when the contract expires
"The city signed a 20-year contract." Given the downtime, will the contract be extended?
Depending on what the facts are, money may be owing to the City if we overpaid for getting rid of sludge. If money is owing to the City, how much is it? I assume that the City will go out and collect it.
Why didn't the sharp-eyed, line-by-line, eagle-eyed Coucillor Budget and the Budgeteers catch this?
Easy---Just so you know, "biosolids processing is financed through the Sanitary Sewer Surcharge which is a self-financing reserve fund and cannot be used for other municipal purposes." In other words, no one would really notice anything about it or care. It's just a few pennies. But those pennies multiplied by millions of gallons of water add up quickly!

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Saturday, May 10, 2008

www.chicagotribune.com/news/specials/chi-black_boxsep20,0,3744954.story
chicagotribune.com
TRIBUNE INVESTIGATION


Of big claims, insiders and a sludge plant
How the Chicago sanitary district bought into a company's dubious track recordFrom Seattle to Stickney
By David Jackson
Tribune staff reporter
September 20, 2007



Eight stories tall and sheathed in corrugated steel, the windowless tower juts above the umber lagoons of the world's largest sewage treatment plant, in west suburban Stickney.Its outer walls are painted white, but Chicago sanitary district officials use a dark nickname for this structure.They call it "the Black Box."Its four 60-foot-tall ovens are designed to each day swallow about a quarter of the district's sludge and churn out 150 tons of fertilizer. The dry pellets, small as mustard seeds, are supposed to be safe enough to spread on farms where food is grown for human consumption.District officials say the $217 million project will help protect a vital public trust: the Midwest's "inland ocean" of freshwater lakes, underground aquifers and sun-splashed rivers.But the company that won the lucrative contract did so based on questionable assurances about its executives' track record at a similar facility, government records show. At the very time one of those executives was persuading Chicago officials to hire his company, Seattle authorities were cutting short its contract. They complained about noxious fumes, fires and unreliable output.Chicago sanitary district officials never reviewed government files in Washington state to verify the claims made by the company, Metropolitan Biosolids Management LLC."I only recall one telephone conversation with the people from Chicago to discuss the project," said John Smyth, project manager for King County's Department of Natural Resources and Parks.The history of Chicago's project also is tangled by the city's old-school insider politics. Records show extensive ties between the sanitary district superintendent who championed the Black Box and the MBM executive in charge of building it today.The showcase plant is now nearly four years behind schedule. The Metropolitan Water Reclamation District of Greater Chicago plans to levy more than $1 million in late charges against MBM. In 2004, top district officials tried unsuccessfully to end the deal because of construction delays and permit disputes.District officials say the past problems have no bearing on the project's prospects and add that some of the delays came because they are closely monitoring MBM's work.The firm was created by former district General Supt. Bart Lynam, who left office in 1978 about a year after a federal jury acquitted him of corruption charges in a high-profile district bribery scandal.Lynam's current corporate partner, and MBM's majority owner, is a division of Veolia, the French-based conglomerate that calls itself the world's largest water company and a pioneer in the global trend toward privatizing government water services. Veolia was not involved in the Seattle operation.In Chicago, district officials expect operations to start in January after a 60-day test to confirm the plant's safety and effectiveness. MBM will own and operate it for 20 years, and the district will pay the $217 million in installments as sludge is processed.In a letter to the Tribune, Lynam said his Seattle plant met its contract requirements, and he called the Chicago project "a very 'green' operation for the good of the community."For Veolia, the Black Box represents a new solution to a pressing public need, and company executives say its future is untainted by Lynam's earlier, shuttered venture.Veolia's own experience, though, shows how pelletizer technology remains a tricky enterprise. In 2003, a fire nearly destroyed a Veolia plant in Toronto that officials hope to open later this year. And in Atlanta, Veolia and city officials are locked in a federal lawsuit over who is to blame for a long-stalled pelletizer project there.The company says it is constantly refining the technology. The Stickney facility, for instance, will have added fire protections and odor controls, making it far better than Lynam's Seattle operation, said Veolia Water Vice President Michael Wheeler. "We want this to be a showplace people come from all over the world to see."A well-placed advocateA first-time visitor might be forgiven for gazing up slack-jawed through the nearly finished building's grated metal floors. Its ovens shimmer with the latent power of rockets on a launching pad. Twisting feeder tubes and squat turbines are housed in a cathedral-tall cinder-block shell. The air pressure will be lowered inside to help draw dangerous fumes through a series of high-tech scrubbers."This is an important project," said the district's current general superintendent, Richard Lanyon, adding that the district needs to find ways to better recycle and even sell its treated sewage.Although the district doesn't stand to lose money in the Black Box deal, which is being financed in part by bonds issued through the Village of Hodgkins, insiders already are profiting. In addition to his role as an MBM principal, for example, Lynam runs a firm that has submitted at least $200,000 in "consulting" bills to serve as a liaison with the district and provide "technical input" and marketing, according to construction invoices examined by the Tribune. Such arrangements are not prohibited.When MBM bid for the project, Lynam found a staunch advocate in the now-deceased Chicago sanitary district chief who oversaw the Black Box contract.Hugh "Mac" McMillan had reported to Lynam at the district during the 1970s, then succeeded him as general superintendent. McMillan left the district, and during the 1980s he and Lynam both served as corporate officers of Paschen Contractors, then a major district contractor.Rejoining the district as superintendent in 1994, McMillan soon launched the Black Box as his administration's top priority. He gave it that secretive name because the district asked prospective firms to craft an innovative design but didn't tell them what sort of technology to use. At district meetings, McMillan brushed back questions about Lynam's Seattle operation, calling it a "success" and "proven technology."In December 2000, after overseeing MBM's selection as the Black Box contractor, McMillan retired to join a key Black Box subcontractor responsible for the project's engineering design, permitting and legal counsel, records show.The district has no "revolving door" policy that limits post-employment work in the private sector, so district officials say McMillan's private-sector affiliations with Lynam were not inappropriate. "It was known to us," Lanyon said of McMillan's ties to Lynam and the contract.A spokesman for Consoer Townsend Envirodyne Engineers, the subcontractor McMillan joined, said he did not work directly on the Black Box account.Lynam's letter to the Tribune said he didn't learn of McMillan's move to Consoer Townsend until after it took place. Lynam added that he and McMillan did not work together at Paschen: "In fact, we lived at opposite ends of the country. He resided in Florida."McMillan died in 2004. Today, his likeness gleams from a metal plaque outside the district office pavilion named after him on Erie Street.A bit of sewage alchemyFreshwater scarcity is emerging as one of the 21st Century's signature issues, and big cities such as Chicago are scrambling to rinse the ceaseless gush of waste from homes and factories.That urgent quest has spawned a multibillion-dollar industry, from boring deep wells that render methane gas from municipal waste to melting sewage residue into a glass aggregate that can be mixed into asphalt.But few places have the vast needs of Chicago's sanitary district. Each day, more than 1 billion gallons of wastewater sluice to one of the modern world's civil engineering marvels. At the 560-acre Stickney Works and six smaller sites, the slush is screened, dried slowly in long ponds or in rapidly spinning drums, fed to cleansing microorganisms and run through anaerobic digesters until it has the clumpy consistency of lawn soil after a spring rain.Each day, the district pays contractors about $27,000 to haul some 300 tons of this final sludge cake to landfills and farms.In the district's map-lined offices, a half-block west of Michigan Avenue's glittering boutiques, global engineering firms vie for wastewater treatment contracts alongside inventors who peddle miracle machines.Here, in 1996, then-General Supt. McMillan announced the Black Box proposal with a sobering speech."At the moment, I am not confident that we have, even today, an ability to dispose of our current production," McMillan told district commissioners.Hauling and landfill costs were soaring, and suburban residents had grown increasingly vocal about noxious fumes at Stickney and other preliminary treatment sites, he said.Like his counterparts across the country, McMillan sought an innovative technology to produce a drier product that would be cheaper to truck. While that process might leave traces of heavy metals and household chemicals, it could destroy enough pathogens to allow the district to market a fertilizer safe enough to spread on food-crop fields.With his Seattle sludge pelletizer, McMillan's friend Lynam proposed just such an alchemy.Boots-in-muck entrepreneurWorkers at Cunningham Manufacturing Co. in Seattle thought a rat had died. They ripped out the walls of an upstairs office bathroom in a vain effort to locate the stink.A few doors away in the swath of shipping firms and factories that form Seattle's South Park industrial district, United Iron Works employees started going home sick.Then 140 South Park workers signed a petition demanding that Seattle officials shut the sewage treatment plant run by Lynam's company. They said its fumes caused stomach flips, sore throats and headaches.This was the back story to the "patented technology" Lynam pitched to Chicago officials.Lynam moved to Seattle after resigning from the district in 1978. There he launched the first of three firms that partnered with giant construction and water companies to bid for government and industry contracts.Starting in the 1980s, Seattle officials were under pressure to tear down five 30-foot-tall sewage digesters stacked on an outcrop of Discovery Park, a trail-laced preserve that tumbles onto beaches rimming Puget Sound.In hopes of removing at least some of the digesters, local authorities in 1989 awarded Lynam's company a 20-year contract to build a pelletizer. But soon after he opened his South Park demonstration plant, the Puget Sound Clean Air Agency cited it for eight air-pollution regulation violations from 1992 to 1994. During that time, the agency took the unusual step of filing a civil lawsuit to force Lynam's company to comply with air-emission laws.From government records and interviews, Lynam emerges as a tireless, boots-in-the-muck entrepreneur who disputed odor complaints as he struggled to keep his experiment afloat."They really tried to make it work," said King County project manager Smyth. And so did local government officials; Smyth was assigned an "odor beeper" so he could quickly address complaints.In his letter to the Tribune, Lynam called the eight Puget Sound air-regulation violations "allegations" and said Seattle's "antiquated sewer system" was the source of any foul smells.Lynam's company, however, did acknowledge odor problems in correspondence with Washington state officials, stating that machinery breakdowns and human error caused the emissions. The firm hired odor consultants, upgraded equipment, retrained staff and at one point cut back plant hours to run only at night.In August 1994, police responding to a fire noticed a stench from 12 blocks away and "believed that there was a decaying corpse in the area," their incident report said.Nine months before the South Park demonstration contract was slated to end, Lynam's company -- then called PCL/SMI -- agreed to "terminate for convenience" and avoid default, a King County report said."They shut down before they got a shutdown order," Smyth said in an interview.For his part, Lynam said his team made improvements to the South Park plant, but "because it was a temporary facility, we agreed to end the project." His company had "gained valuable experience and knowledge," which was the plant's purpose, he said.Seattle officials still hoped to replace the Discovery Park digesters so they pressed forward with Lynam's strategy to build a second, larger plant in the park. "We decided to go ahead," Smyth said.Safety concerns stemming from two flash explosions delayed that plant's required performance tests, according to a local government report. And odor problems persisted."Smells like a sewer outside," Albert and Della Gordon said in a July 1996 complaint to the clean-air agency.Lynam told the Tribune that the odor complaints stemmed from nearby municipal pipes and said his company bolstered the facility's fire protections.Still, his fertilizer pellets sometimes came out fluffy, making them difficult to truck and spread on fields. One food grower stopped taking deliveries after tractor drivers and farmworkers complained of breathing difficulties and skin rashes. "We do not wish to put our employees at risk," John Huffman of Natural Selection Farms Inc. wrote in a May 1996 letter.Lynam told the Tribune that the dust was "pathogen free."On Nov. 13, 1996, a week after being elected governor of Washington, King County Executive Gary Locke sent Lynam a notice of termination "effective as of the date of this letter.""By ending this experiment now, we can lower rates, reduce odors and ensure environmental safety," Locke announced.In public statements about the termination of PCL/SMI's contract, King County officials said the venture was cut short "for convenience, not cause."Lynam cites that phrase as evidence that his Seattle project "met the contract requirements."But Smyth gave a different explanation. "What that essentially means is that we wanted out of the deal but didn't want to go through long and drawn-out litigation," he said.At the time the Seattle contract was canceled, Lynam told local reporters that his company had been blindsided. "This came as a complete shock to us," he said. "I know what we are doing is environmentally right. This is unquestionably the best way to do it."To this day, many Seattle officials and activists admire Lynam's intentions. "He's a publicly spirited guy. He wants to make it work for all the right reasons," said Metropolitan King County Councilmember Larry Phillips.But municipal sludge is smelly and combustible, Phillips added. "It takes time to get this perfected, and locally we just ran out of time."Even as his Seattle venture was being cut short, Lynam began laying the groundwork for a new future in Chicago.Questions raised, rejectedIn the months after McMillan announced his Black Box proposal, Lynam's PCL/SMI company was one of 27 firms that sent the district expressions of interest in bidding.On Nov. 15, 1996, two days after King County mailed Lynam its notice of termination, Chicago officials wrote Lynam to ask for "additional information" about his Seattle plant, district records show.In his response a month later and in other bid letters, Lynam said his 1990s Seattle operation "successfully" produced 60 tons of dry fertilizer pellets per day.According to government files examined by the Tribune under Washington state's Open Records Act, that facility never passed the 60-ton-per-day acceptance test required by King County authorities. It produced an average of only 41 dry tons of pellets per day during its best month.Lynam's December 1996 bid letter also said his Seattle operation "had no violations of our permits."That was true of his second plant, but the first South Park facility paid penalties for regulation violations and faced the government lawsuit. In recent interviews, Chicago district officials said they were unaware of the South Park plant's infractions."Violations always matter," General Supt. Lanyon told the Tribune. But Lanyon added that Lynam needed only his second plant to qualify Metropolitan Biosolids Management for Chicago's contract: Bidders had to have run a facility that produced 30 dry tons of treated sewage and operated for one year during the last five years; it didn't need to be currently functioning. Lynam's second Seattle venture matched those specifications.He told the Tribune that King County government officials had "made a political decision" to cut short his company's contract because pressure from a local union made it difficult for the city to supply enough sludge. In a 1997 newsletter, a union leader claimed credit for stopping Lynam's company.In interviews, though, union officials said the opposition Lynam cites did not arise until the plant's final 90-day trial period. And Smyth called those union troubles a "misleading" explanation for why the county cut short the contract. By then, he said, the union resistance was "another nail in the coffin."Back in Chicago, numerous bids were winnowed. MBM's proposal, which was significantly lower than the others, gradually advanced through several years of open competition.Finally, at a November 2000 district board meeting, Commissioner Patricia Young asked McMillan why Lynam's Seattle plant was shuttered. "Can you explain what happened with that operation, why it failed?""It did not fail," McMillan said. "We have representations from the owners of that facility -- I'm talking about the municipal agency -- that it did not fail to meet the contract requirements.""So why is it not operating anymore?""Union disputes.""Union disputes?""That's correct," McMillan said.A month later, at a December 2000 board meeting, Young offered a motion that the district adopt revolving-door hiring restrictions like those enforced by the City of Chicago and Cook County.Again, McMillan shut her down. No commissioner seconded Young's motion, so it failed.Days later, with Young as the lone dissenting vote, commissioners authorized the district to award Lynam's company the Black Box contract.----------dyjackson@tribune.com
Copyright © 2008, Chicago Tribune

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Friday, May 09, 2008

Sewage sludge pellets: fire and explosion risks

The article below was published by the Ontario Fire Marshall's Office in the Publication: Ontario Fire Service Messenger November/December 2002


Sewage sludge pellets: fire and explosion risks


There are rabbit food pellets, pellets for guns, wood pellets for burning in stoves, and there are even sewage sludge pellets! What will they think of next? Introduction Sewage sludge is the nutrient-rich organic byproduct of the wastewater treatment process. It contains most of the nutrients required for crop growth, and organic matter, which can enrich soil, and may also be called “biosolids”.

For some people, spreading biosolids on farmlands is considered to be perfectly safe way of returning nutrients to the ground if appropriate procedures are in place. Recycling this nutrient source is viewed to be better than putting it in a landfill site or incinerating it. Other people believe that cities are simply transferring urban pollution to the countryside, and site concerns about the fumes, respiratory infections and other negative health effects that may stem from exposure to biosolids, and the potential for contaminated well water and water courses.


Sewage sludge can exist in liquid forms and can also be converted into granules or pellets by removing the moisture. In this solid form, pellets are easier to handle and store, and transportation costs are reduced, as compared to liquid sludge. Although people may be aware of the environment aspects associated with the disposal of sewage sludge, they may not be aware that sewage sludge pellets have been associated with numerous fires and explosions.

For instance, Sludge pellets stockpiled at a farm in Windsor caused a smoldering fire. There were a series of explosions in a Windsor pelletization plant, most recently in October 2002. The City of Toronto had problems with the self-heating of sewage pellets in a storage silo. An explosion at the Miloganite plant in Milwaukee in 1996 caused serious injuries to a worker and $ 4.5 million worth of damage to the plant and property.


This article has been prepared to provide information on potential fire hazards associated with sludge pellets, safe storage and effective fire suppression. Self-heating properties of the product: Sewage sludge is mainly derived from human waste, but may also contain animal products, paper, high fat content from processing plants, heavy metals, organic contaminants and petroleum products from petroleum and diesel spills. When formed into pellets, the finished product has less than 5% moisture content. Should the moisture content of this material reach between 5- 10% by weight of the product, aerobic biological decomposition occurs, causing self-heating.

Water generated by this process is absorbed by the surrounding sludge, which intensifies the self-heating process. A smoldering fire may occur if the heat generated by this self-heating process is not dissipated to the surroundings. Processing and Handling In the initial stages of sewage treatment, the digestion process produces methane and carbon dioxide. If raw sludge is stored it will decompose and produce hydrogen sulphide and other volatile sulpher compounds. With the addition of chemicals to dewater the sludge, hydrogen sulphide and ammonia may be released. Conversion of sewage sludge into granules or pellets, by removing the moisture, is the final stage of the sewage treatment process.

The amount of dust produced in the drying process and later processing is affected by the method of drying and type of final product. Sewage sludge dust is about the same size and similar hazard as wood dust. Depending on the design of the plant, there is the potential for a dust explosion to occur at the main dryer, dust collector and handling plant, pelletizer and final product discharge plant.

In pellet form the product is sufficiently hard to withstand the normal conditions of mixing, handling and transportation without producing excessive levels of dust. These pellets have a relatively low auto-ignition temperature, as low as 2650C, and may be easily ignited without process precautions. A risk assessment followed by implementation of suitable prevention and protection measures is required for all parts of the process.

Special attention should be given to the specific hazards associated with the generation of methane, hydrogen suphide, and dusts. Appropriate ventilation, relief venting, suppression systems, containment features, avoidance of ignition sources, and safe handling and storage practices also need to be considered. Storage Once dried, pellets may self-heat to the point of ignition and slow burn.


To minimize the potential for self-heating, sewage sludge pellets should be kept cool and dry and should not be stored in large piles. Storage silos should be designed to aid cooling and be sized to allow thermal dissipation of heat. For this reason, tall narrow silos are preferable to wide silos. Where significant levels of dust are likely to be produced in the storage silos, they should be designed to mitigate the effect of any explosion. The simplest protection is the provision of explosion relief panels venting to a safe location. Silos should be designed to identify and contain a fire. A slow burning silo fire is likely to be starved of oxygen and therefore produce carbon monoxide. A carbon monoxide detector in the silo will indicate an incipient fire.

As well, multi-point temperature probes may be installed to monitor the temperature of the product. As an alternative to indoor storage, pellets should be transported to a site location and be off-loaded and turned into the soil as soon as possible. If this is not possible, the material should be spread on the ground evenly in the form of a very thin layer. This configuration will dissipate any heat generated into the ground and atmosphere.

Fire suppression

Inside a silo, an inert gas can be used to contain, but not necessarily extinguish, a fire. The injection of an inert gas will cause a drop in temperature, but may only have a limited effect. The temperatures should be monitored for several hours before deciding if the fire has been controlled. Procedures to deal with a silo fire may include the gradual emptying of the silo to a safe location. Outside, a sewage sludge pellet fire typically smolders at the surface with a relatively low burning temperature and emits dense white smoke and products of incomplete combustion. The smoke may contain organic acids and other compounds that are irritating agents.

The simplest way to deal with such a fire is to dissipate the heat by spreading out the pellets. It may also be extinguished by confining and smothering. Alternately, the pellets may be mixed into the soil or stamped with heavy earth moving equipment. In some cases, the use of Class A foam may be considered for fire suppression. Class A foam is a special formulation of hydrocarbon surfactants, that reduces the surface tension of water and provides for better water penetration and increased effectiveness. Class A foam acts as a surface barrier to stop or prevent further combustion. The use of water to suppress this type of fire is controversial.

The application of water may actually support a fire by contributing to the process of aerobic decomposition. Further, adding water may return the dried sewage into liquid sewage and create additional leachate and runoff. In turn, this may contaminate ground and surface waters surrounding the site and could cause significant environmental and health risks. Overall, fire fighting tactics need to consider a range of circumstances, not the least of which include the size of fire, location, wind/weather conditions, water supply, personnel safety, access to heavy equipment, and environmental impact.

Conclusions

Although fires involving sludge pellets are not common occurrences, they do tend to attract a great deal of public attention and challenge the fire service. By working with the public, pellet factory owners, and owners of sites used to spread sewage sludge pellets, the fire service can ensure that safe practices are employed, thereby protecting the public, environment and emergency responders.

Article prepared by OFM Fire Protection Engineers Beth Tate and M. Mailvaganam.

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