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HomeMy WebLinkAbout8.a. Report on Olmsted County Mass Burn TripWe're burning to have a better future. There was a time — just a few decades ago — when the Earth's resources seemed infinite. We used them and often abused them freely. There was another time — just a few years ago — when most of us realized abruptly how untrue that was. Some of us reacted with a sense of hopeless- ness and doom. Today we are entering a period of maturity and wisdom about our enAron- ment. We know that damage has been done; but we also know that much can be undone and that much future damage can be prevented. We are coming to understand our stewardship and responsibility toward the planet on which we live. And we are teaming how to carry out our responsibility. Olmsted County's Waste -to -Energy project and its recycling center are one way of doing that. • We are making use of a resource we once regarded as simply "garbage" • We are generating power without tapping our limited resources of coal and oil • We are cleaning up our air • We are reducing the eyesore (and "nose -sore") of landfills • We are keeping landfill pollutants from poisoning our ground water Our Waste -to -Energy plant is perhaps the 40th such facility built in the United States, and one of about 1500 in the world. As this brochure was being written, dozens more waste burning plants were under construction. A project like this relies on science, technology, business, government and you — the individual - if it is to do its part in keeping the environment healthy. The key to cleaning up the environment is probably under your kitchen sink right now. It's easy to recycle. Here are the materials our recycling center can handle, and some tips on how to prepare them. Aluminum — Everything should be clean and dry. (beverage cans You may crush the cans if you prefer. & aluminum foil) — No steel or tin food cans Newspaper — Tie it with twine or put it in grocery bags — No glossy, colored paper or magazines — Paper should be clean Glass — Remove all metal and caps (clear, brown — Do NOT crush or green) Corrugated cardboard Office/white paper —.Break boxes down flat — Bundle like newspaper How to reduce the waste stream. • Avoid disposable, convenience items • Buy products without bulky, obvious, unnecessary packaging • Look for products that are recyclable, repairable or longer -lasting • Reuse containers wherever possible • Allow grass clippings to return to the soil Compost leaves and kitchen scraps • Use sheets of paper on both sides • Tell your friends!! Project Team Olmsted County Board of Commissioners Douglas A. Krueger, Chairperson Harley Boettcher, Commissioner James M. Daley, Commissioner Carol Kemper, Commissioner William Pudwell, Commissioner Richard G. Devlin, County Administrator Charles R. Michael, P.E., Project Manager Consulting Engineer HDR Techserv, Inc. Minneapolis, Minnesota James W. Booty, P.E., Project Manager Floyd J. Forsberg, P.E., Program Manager/Ltason Major Equipment Suppliers Riley Stoker Corporation, Worcester, Massachusetts Takuma Company, Ltd., Osaka, Japan Murray Turbomachinery, Burlington, Iowa Indeck Power Equipment, Wheeling, Illinois GEA Power Cooling Systems, San Diego, California Engineered Crane Systems, Alpharetta, Georgia Webb Material Handling Equipment, Chicago, Illinois B 6 S Miljoteknik, Aarhus, Denmark Facility Constructor M. A. Mortenson Company Minneapolis, Minnesota i)Olmsted Waste-to-Eneray 2128 Campus Drive, S.E. Rochester, MN 55904 (507) 285.8231 �L''9n°„'� � S^M'.�p 'Rid.' 4y� , • i 4 Y+✓�::AF p �u � {ru .,. {, '�~k Tl.�6�'$�.l L..��+... � ` i �M' t_.".Aa. { • �*` "�.^!i .kYr•+ ' , dim 77 V07: u b%wt�_.. T iv y q� yr rA q 1' �L''9n°„'� � S^M'.�p 'Rid.' 4y� , • i 4 Y+✓�::AF p �u � {ru .,. {, '�~k Tl.�6�'$�.l L..��+... � ` i �M' t_.".Aa. { • �*` "�.^!i .kYr•+ ' , dim 77 V07: u b%wt�_.. P • Garbage doesn't belong in the environment. Instead, we burn it for energy. Now garbage is energy. Light. Heat. Power. Steam to keep Olmsted Commun- ity Hospital's patients warm. Electricity to light the county human services campus. Now Olmsted County Waste -to -Energy is making non -recyclable garbage useful by burning it under high-tech conditions to generate energy. We're still recycling things like aluminum, glass and several types of paper (a big new recycling facility operated by Ability Building Center is part of the Olmsted Waste -to -Energy project). But all the rest of Olmsted County's non- toxic refuse goes into the combustion chamber. Every ton of "useless" trash we burn is 4,500 pounds of coal that won't have to be mined. Garbage doesn't belong in the environment. Instead, we burn it for energy. But that's not even the best part. The best part is what we're not doing with garbage. We're not dumping it into landfills anymore, where its residue seeps through fractures in the bedrock to poison our groundwater. We're not blighting the landscape with it. We're not wasting it. Olmsted Waste -to -Energy Facility. Olmsted Waste -to -Energy (and YOU) can clean up our landfills and help preserve Minnesota's resources. In 1983, it became apparent that the Olmsted County landfill was nearing its capacity and that an alternative would have to be found. Groundwater prob- lems made another landfill one of the least desirable options. We looked at other methods. But in the end, the Waste -to -Energy option had three clear advantages. It was clean. It cost less to operate than a landfill. Arid it produced an easily useable end product. Olmsted Waste -to -Energy: a tour of the campus and the plant. 1. Olmsted Recycling Center When individuals and hauling companies come to the Olmsted Waste -to - Energy Facility, their first stop is likely to be the recycling center, located on the northeast edge of our 20 acre campus. Ability Building Center, which has long been a major recycler, operates the center for Olmsted County. The center is presently set up to recycle: • Three colors of glass (clear, green and brown) • Cardboard • Aluminum • Computer paper • Newspaper • Ledger paper There's also a document destruction service for businesses and government agencies. Up to 20% of everything brought to the Olmsted Waste -to -Energy Facility can be recycled. About 50% of this 19,000 square foot building is devoted to the recycling process itself. Trucks and cars unload on the east side; the recyclable materials are crushed, shredded, baled, etc.; then semis pull up to the loading dock on the west side of the building to take them to a variety of markets. An almost equally large area is devoted to shredded paper and baled card- board storage. ABC sells this material in local markets for animal bedding. Since the bedding need is seasonal, a lot of off-season storage is needed. The smallest section of the building contains lunchroom and rest areas for center employees and (very important) a redemption center where you're paid for your recyclable goods. 2. Our wooded campus Our campus looks like a park. Grassy meadows and hundreds of mature hardwood trees were left undisturbed in the building of the plant; and where we did have to disturb the natural growth, we replaced it with new landscaping. Look up. The air above our "park" is clear. On a cold day, you'll see vapor 3 E E 0 rising from the stack, but usually you'll see nothing. Most pollutants are either burned up by the high temperatures the plant generates or are caught in the electrostatic precipitators. The remaining low level emissions are clear. 3. The weigh station Commercial haulers stop here to have their trucks weighed; the scale auto- matically records the weight and the hauler's account number for billing. Individuals with cars, trucks or trailers of trash stop here to pay, just as they used to do at the county landfill. 4. The plant A. TIPPING HALL — Refuse trucks enter through the west door, back up to one of five openings and tip their loads into the storage bunker. Then they drive out through the east door. The doors open automatically when sensor coils detect an approaching truck. Only commercial trucks ever enter the tipping hall. Cars, pickups and trailers leave their refuse in another area outside the plant. B. STORAGE BUNKER — The bunker is 30 feet deep, 55 feet wide and 110 feet long, and holds up to 200,000 cubic feet or 1,300 tons of refuse (that's 100% of the refuse generated in Olmsted and Dodge Counties in an average week and a portion of the refuse from Wabasha and Goodhue Counties). During the Summer months, about 250 tons of refuse is brought in each day. In Winter, about 160 tons. Since the plant operates 24 hours a day, seven days a week, the bunker will never actually fill up. The extra capacity allows operation to continue on weekends and holidays. Visitors comment that the lack of odor and dust is a pleasant surprise. That's because the combustion air for the boiler is pulled across the bunker by the forced draft fan beneath the combustion chamber; the odors and dust are K. CHIMNEY actually burned. Fh, MO ir ■'L■ ELECTRICITY i STEAM ss STEAM H. TURBINE =STEAM - H. TURBINE DRUM GENERATOR 1I GENERATOR i iI }ti w w TO DISTRICT HEATING G. BOILER 0 ob F. COMBUSTION 00000CHAMBER ECONOMIZER J. ELECTROSTATIC PRECIPITATORS ATES00o0o 70 000p UNDERFIRE JI AIR 11�N I. ASH REMOVAL Q � 5 11 INDUCED DR II ►FT FAN The average person throws away 4 pounds of garbage a day. That adds up to almost 1500 pounds a year! C. CRANE AND GRAPPLE — High above the storage bunker, a huge grapple is suspended from a six-ton bridge crane. The crane travels from one end of the pit to the other as the grapple descends to take bites of the stored materials. The grapple's jaws measure 18 feet across when open and can grasp more than four cubic yards of material at a time. The grapple feeds one of the two furnaces every four to five minutes. In between furnace feedings, the operator uses the grapple to mix the mate- rials in the pit, making sure that everything gets properly mixed for even heat content distribution. There are actually two cranes and two grapples, each with its own set of controls. The second system is primarily used as a backup, although both furnaces can be stoked at once during peak periods (a lockout keeps the two grapples at least five feet apart). If a third furnace is added, both systems will be activated. D. CONTROL ROOM — High above the bunker, an operator guides the movements of the crane and grapple from a central control room equipped to monitor and manage the entire operation. The operator positions the crane; automatic controls raise and lower the grapple and work its jaws. Dozens of remote monitors allow the operator to observe everything from the furnace fuel chutes to the weigh station outside the plant (if necessary, the operator could control the truck scales). The operator carefully observes the contents of the grapple and the pit. If the operator spots an item which may be unacceptable to the system, the grapple is directed to deposit it in the loadout at the far end of the building. Here, it can be inspected more closely and, if necessary, hauled to a landfill or a scrap dealer. E. FUEL LOADING CHUTES — The grapple releases its load of refuse, which falls 26 feet down the water cooled chute into the combustion chamber. Lasers monitor the level in the chute and tell the operator when another load is needed. There are two chutes (one for each furnace), which the operator feeds alternately. F. COMBUSTION CHAMBER —As materials fall, four nickel -chromium alloy reciprocating grate sections tumble them for more efficient burning. As it passes over the first two grates, the refuse is warmed and dried by heat rising from the combustion chamber. At the third grate, the majority of combustion occurs. The fourth, or burnout, grate moves the ash and residue into the removal system below the furnace. 200 tons of refuse per day — 8.34 tons per hour — tumble into the chamber for burning. With temperature computer -controlled at a nearly constant 1800 degrees F, combustion efficiency is ensured. Our Waste -to -Energy plant is the first in the nation to have Takuma's Auto- matic Combustion Control. This microprocessor -based system has three important, related benefits. Because it constantly monitors and reacts to conditions in the chamber, burn levels always remain at maximum efficiency, steam pressure and flow are constant and (because of the efficient burning) gasses such as carbon monoxide do not escape up the stack in large quantities.