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High-Powered Plasma Turns Garbage Into Gas
<img alt=”Photo: Kevin Van Aelst” src=”/magazine/wp-content/images/20-02/ff_trashblaster_f.jpg” title=”Feature” width=”315″/>
Photo: Kevin Van Aelst
From the highway, one of the biggest landfills in the US doesn’t look at all like a dump. It’s more like a misplaced mesa. Only when you drive closer to the center of operations at the 700-acre Columbia Ridge Landfill in Arlington, Oregon, does the function of this place become clear. Some 35,000 tons of mostly household trash arrive here weekly by train from Seattle and by truck from Portland.
Dump trucks inch up the gravel road to the top of the heap, where they tip their cargo of dirty diapers, discarded furniture, lemon rinds, spent lightbulbs, Styrofoam peanuts, and all the rest onto a carefully flattened blanket of dirt. At night, more dump trucks spread another layer of dirt over the day’s deposits, preventing trash from escaping on the breeze.
But as of November, not all the trash arriving at Columbia Ridge has ended up buried. On the southwest side of the landfill, bus-sized containers of gas connect to ribbons of piping, which run into a building that looks like an airplane hangar with a loading dock. Here, dump trucks also offload refuse. This trash, however, is destined for a special kind of treatment—one that could redefine how we think about trash.
In an era when it’s getting more and more confusing to determine where to toss your paper coffee cup—compost? recycle? trash? arrrgh!—and when no one seems to have a viable solution to the problem of humanity’s ever-expanding rubbish pile, this plant represents a step toward radical simplification. It uses plasma gasification, a technology that turns trash into a fuel without producing emissions. In other words: a guilt-free solution to our waste problems.
Recycling is all well and good. But it hardly addresses the real problem we have with our household waste: We throw two-thirds of it in landfills while somehow managing to feel virtuous that we put last night’s empty wine bottle in the recycling bin. Surely we could do better, environmentally and economically.
There is, in fact, value in trash—if you can unlock it. That’s what this facility in northern Oregon is designed to do. Run by a startup called S4 Energy Solutions, it’s the first commercial plant in the US to use plasma gasification to convert municipal household garbage into gas products like hydrogen and carbon monoxide, which can in turn be burned as fuel or sold to industry for other applications. (Hydrogen, for example, is used to make ammonia and fertilizers.)
Here’s how it works: The household waste delivered into this hangar will get shredded, then travel via conveyer to the top of a large tank. From there it falls into a furnace that’s heated to 1,500 degrees Fahrenheit and mixes with oxygen and steam. The resulting chemical reaction vaporizes 75 to 85 percent of the waste, transforming it into a blend of gases known as syngas (so called because they can be used to create synthetic natural gas). The syngas is piped out of the system and segregated. The remaining substances, still chemically intact, descend into a second vessel that’s roughly the size of a Volkswagen Beetle.
This cauldron makes the one above sound lukewarm by comparison. Inside, two electrodes aimed toward the middle of the vessel create an electric arc that, at 18,000 degrees, is almost as hot as lightning. This intense, sustained energy becomes so hot that it transforms materials into their constituent atomic elements. The reactions take place at more than 2,700 degrees, which means this isn’t incineration—this is emission-free molecular deconstruction. (The small amount of waste material that survives falls to the bottom of the chamber, where it’s trapped in molten glass that later hardens into inert blocks.)
The seemingly sci-fi transformation occurs because the trash is blasted apart by plasma—the forgotten-stepsister state of matter. Plasma is like gas in that you can’t grip or pour it. But because extreme heat ionizes some atoms (adding or subtracting electrons), causing conductivity, it behaves in ways that are distinct from gas.
Dozens of firms are racing to find the right formula to use plasma to blast garbage into gas. Yet despite incremental improvements in the technology, plasma gasification has proved too energy- and capital-intensive for real-world use on everyday trash. If the value of the syngas produced doesn’t offset the amount of energy required to power the furnaces and melt the trash, what’s the point?
Now S4 cofounder Jeff Surma may have finally solved that problem. (S4, by the way, refers to the fourth state of matter: plasma.) The 52-year-old chemical engineer is convinced that he can transform garbage from something we toss into something we value—and get it to work on a vast scale. He has already made enough advances with the technology to attract millions of dollars in backing from Waste Management, the $12.5 billion trash hauling, recycling, and disposal behemoth, which owns the landfill here in Arlington.
Still, it’s a long shot. The US generates about 250 million tons of trash a year. Even with recycling and composting facilities tackling an estimated 85 million tons of refuse per year, it would take thousands of new plants much bigger than this one (and another S4 facility being constructed in McCarran, Nevada) to handle the nation’s municipal trash output. That’s a lot of plasma.
<img alt=”Photo: Kevin Van Aelst” src=”/magazine/wp-content/images/20-02/ff_trashblaster2_f.jpg” title=”Feature” width=”315″/>
Photo: Kevin Van Aelst
On a summer afternoon, Surma steps out of his Mercury Mariner, replaces tasselled loafers with work boots, and dons a yellow hard hat. He has a runner’s physique and a shock of white hair, and wears wraparound sunglasses. Today he’s guiding potential customers from the chemical industry around the Arlington plant, explaining how it all works. Later he confides: “If we’re still here in two years, telling you what we plan to be doing, you can come back and call bullshit on us.”
Here’s a short history of how Surma’s trash blaster came to be: Fresh out of graduate school at Montana State University in 1985, he was hired by Pacific Northwest National Laboratory, a research facility in Richland, Washington. He was there to work on an especially hideous mess: the Hanford Nuclear Reservation, just down the road. Beginning with the Manhattan Project, the US government cooked most of the plutonium for America’s nuclear weapons arsenal at Hanford. With its nine nuclear reactors, giant plutonium processing plants, and buried tanks of radioactive sludge, the site has earned the dubious distinction of being one of the most contaminated nuclear waste sites in the Western Hemisphere.
Surma’s first project was to work on so-called joule-heated melters, an experimental method for processing nuclear waste. “We basically fed this muddy slurry into a chamber that was heated with coils,” he says, “almost like the coils on an electric stovetop.” This chemical process, known as vitrification, immobilizes radioactive materials in an inert form of glass. By and large, the system worked; the team was able to convert waste into more than 30 four-foot-tall canisters of vitrified glass.
But that pricey and delicate process made sense for only the worst materials on the site. Hanford also has huge quantities of more heterogeneous trash, much of which contains low-level radioactivity. “It couldn’t go to a landfill,” Surma says, but it wasn’t suited to vitrification, either.
Surma went prowling through the literature for other waste-treatment techniques and was soon reading up on tech known as the plasma torch. In the 1960s, scientists at NASA wanted to learn more about the effect of extreme heat on manned spacecraft reentering the atmosphere. They developed plasma torches to mimic those conditions.
Meanwhile, Surma learned, the practice of using plasma for processing waste had been around for decades, primarily in the metal and chemical industries. Oil refineries, for instance, spend $2,000 a ton to dispose of their toxic sludge with plasma gasification. But few people ever gave the technology much serious consideration for treating everyday garbage because of the high energy costs and because the heterogeneity of municipal solid waste makes it that much harder to efficiently untangle.
Jeff Surma wants to transform garbage from something we toss into something we value.
And then there’s the problem of the toxins in heavy metals—materials from busted televisions, microwave ovens, dead batteries, broken thermometers, old paints—which aren’t broken down by plasma. If you don’t want hazardous leftovers making their way into, say, the water supply, you have to find a way to safely sequester the stuff. Those especially nasty substances, of course, were Surma’s specialty.
Around the same time that Surma was looking into all this, a physicist at MIT’s Plasma Science and Fusion Center named Dan Cohn was searching for plasma technology’s possible environmental applications. He placed a call to Pacific Northwest, asking if anyone at the lab was doing plasma research, and he was connected with Surma. Before long they were brainstorming how to take the technology beyond merely disposing of specialized toxic waste: They wanted to go after the billions of tons of common household trash.
The next step was to pull in a retired engineer from GE named Charles Titus. He was an expert in high-voltage engineering and had become convinced that metal torches, which tend to get damaged by the very heat they deliver, were the wrong technology. It would be better to create plasma with an electric arc strung between two graphite electrodes. (Titus died in 2007.)
But the trio also knew that if they were going to aim for the massive market in municipal solid waste, they needed a clean system with essentially no byproducts. Otherwise, their technology would look like incineration in disguise. One evening in 1994, over a meat-lover’s pizza and another round of Sam Adams at a Bertucci’s restaurant near MIT, Surma wondered aloud about combining the plasma attack with the vitrification technology he’d mastered at Hanford to handle the nasty leftovers. The concept was captivating, but they would have to find a way to run that kind of machinery without also needing a dedicated hydroelectric dam to power it.
To combine the vitrification and plasma-zapping processes in the same chamber, they needed to keep the molten glass at the bottom of the vessel from cooling down; continuously having to reheat it would interrupt key chemical reactions and could quickly lead to exorbitant energy costs.
Keep it hot. Sounds straightforward, but it isn’t. While the molten soup needs alternating current to maintain steady temperature, the electric arc for the plasma runs on direct current. Titus, the electricity guru, said he could rig the AC/DC combo, and that evening they quickly sketched out details for a system that would enable DC and AC to cohabitate within a plasma gasification furnace jacked up with a melter. This tandem approach, the men realized, promised to provide just enough energy to sustain the plasma and atomize trash, while keeping the glass in a molten state. “But no more energy than that!” Surma says. The next day they wrote up the details in an invention disclosure, a kind of shortcut for protecting an idea in advance of filing a full patent.
Within a few months, the three scientists felt ready to launch a company. Cohn knew a guy who had made a killing selling his frozen-dinner company to ConAgra and was looking to invest in promising technologies. So one afternoon in 1994, in a dimly lit room with mahogany walls at Manhattan’s Chemists’ Club, they presented the melter idea to the frozen-dinner guy, who had brought along a venture capitalist friend to offer advice. Surma, Cohn, and Titus got the money, as well as a complementary booklet of coupons for chicken potpies.
The plasma-enhanced melter now operating in Oregon breaks down everyday garbage into its constituent atomic elements. Here’s how it works.
A conveyer belt delivers shredded trash into a chamber, where it’s mixed with oxygen and steam heated to 1,500 degrees Fahrenheit. This process, called gasification, transforms about 80 percent of the waste into a mixture of gases that are piped out of the system.
2/ Plasma Blasting
Material that doesn’t succumb to the initial heat enters a specially insulated cauldron. An 18,000-degree electric arc that runs between two electrodes creates a plasma zone in the center of the container. Exposed to this intense heat, almost all the remaining trash gets blasted into its constituent atomic elements. Again, the resulting gases are piped out and sequestered.
3/ Hazmat Capture
At the bottom of the cauldron sits a joule-heated melter, which is like coils on an electric stove and maintains a molten glass bath that traps any hazardous material left over from the plasma process.
Swirling in a taffy-like ooze, the molten glass is drawn out of the system. Now inert, it can be converted into low-value materials such as road aggregate. Metals are captured at this point, too, and later recycled into steel.
5/ Fuel Capture
The sequestered gases, known as syngas—mostly carbon monoxide and hydrogen—are cleaned and can be sold and converted to fuels like diesel or ethanol to produce electricity onsite or elsewhere.
Illustration: James Provost
They called their company Integrated Environmental Technologies (eventually InEnTec), and in 1995 Surma took a leave of absence from Pacific Northwest to run it. It was slow going at first. Surma and his team of three engineers didn’t finish the prototype melter until 1997. They sold their first commercial units, geared specifically for hazardous waste, in 1999. Early customers included Boeing and Kawasaki, which produce heaps of hazardous waste and have to pay dearly to deal with it. Manufacturers save big money when they don’t have to contract with someone else to dispose of their waste, and gleaning useful materials or gases out of a treatment process only adds to overall savings.
But when InEnTec tried to venture into markets beyond the manufacturing and chemical industries, things always went wrong. Surma sold a unit to a company in Hawaii that used it to process medical waste, but that firm ended up folding. Next, he tried to set up a medical waste processing operation in northern California, this time to be run by InEnTec itself. But a group of impassioned citizens stepped in to oppose the project. They didn’t—or refused to—understand the science of plasma gasification and the absence of emissions. All they heard was “medical waste treatment plant” (and some version of “right down the street”). After an 18-month struggle, Surma jettisoned the project in 2007. It was a moment of truth. He realized that the business had somehow drifted from the founders’ original vision. “It was always our intent, from the very first patent, to go after the municipal solid waste stream,” he says. “But customer pull drew us into hazardous- and medical-waste treatment.”
Surma decided to retrench—to get back to the goal of processing what he calls the granddaddy of waste streams. Together with InEnTec’s chief engineer, Jim Batdorf, he spent three days planted in front of a whiteboard, trying to come up with ways to make it more economically feasible to use the melter on household garbage in all its heterogeneous glory.
The breakthrough alteration they came up with was to stack a conventional gasifier atop the plasma-enhanced melter. The trash undergoes heating and treatment by way of this preliminary gasifier, then moves into the chamber with the plasma zapper and vitrification. It’s like partly defrosting a turkey before putting it in the oven. This strategy improves efficiency because it takes less energy for the plasma to blast materials that have already undergone some heating. The leftovers, meanwhile, drop down into the molten soup, which flows in a slow, taffy-like ooze of glass and liquefied metal out the bottom of the system. At the same time, syngas piped out of the plant can be burned as fuel to, in theory, supply all of the power needed to run the melter itself.
The actual plant built by S4—a wholly owned subsidiary of InEnTec—is still so new that it remains to be seen whether the quality and quantity of Surma’s syngas matches the predictions and test data gathered so far. “The goal is to take waste and produce a product that is used for energy or for some other process,” says Tom Reardon, a vice president with the waste consultancy Gershman, Brickner & Bratton. “They’ve proven they can produce a syngas. But from it, can they produce the fuel they’re supposed to?”
“The easy answer used to be: Store it in a can, put it in a truck, and then send it to a big hole in the ground.”
What Surma didn’t know back when InEnTec was retooling for municipal trash was that, starting in 2005, executives at Waste Management had quietly dispatched a team of experts and consultants to study plasma gasification. If it looked like a worthy technology, they would invest. After a review that lasted more than two years, they determined that InEnTec was one of the few firms in the world whose technology looked viable. In 2008, Surma found himself on a flight to Houston to give Waste Management executives a presentation about his plasma-enhanced melter.
The company’s executives know better than most that we can chuck trash in landfills for only so long. “The easy answer used to be: Store it in a can, put it in a truck, and then send it to a big hole in the ground,” says Carl Rush, a senior vice president at Waste Management. “We’re moving away from that as a society.” Why? People don’t like it, it’s becoming costlier to transport and bury garbage, and—even in the spacious American West—landfills are gradually butting up against more backyards and inching their way toward local water tables.
Trash-to-fuel technology has in fact been around since the 1970s and involves burning waste to generate electricity. But that method, no matter how fancy your emissions scrubbers, invariably produces a stew of byproducts that need to be disposed of. Consequently, environmentalists—and some in the industry itself—have remained skeptical of trash-to-fuel. Nevertheless, Rush and his team suspected that entrepreneurs might have cracked the problem and began searching for experimental technologies to invest in. Among the more than two dozen companies Waste Management has recently added to its portfolio are a startup with a specialized method for producing compost, a firm that uses gasification to turn biomass into synthetic gas, and a company that converts mixed and contaminated waste plastic into synthetic crude oil.
Not all of these startups will make it, and it’s possible that most won’t. But Waste Management bosses hope they will help accelerate the transition to an era in which the very idea of garbage itself is garbage—and they want to be positioned to profit when that time comes.
The INENTEC Hydrocarbon Conversion Test Facility is located next door to Richland’s tiny airport. Inside the cavernous building stands the first prototype of the plasma- enhanced melter, which is less than a third the size of the unit 85 miles away in Arlington. This is where Surma and his team refine and tune the blasting process in an ongoing series of upgrade experiments, melting materials from everyday trash to asbestos, PCBs, hazardous chemical sludge, and discarded electronic equipment. Data gleaned here will help with tweaks at the plant in Arlington and inform the design and operation of S4′s next commercial melters.
Today they’re testing a chemical called toluene, one of the most stable organic compounds there is. That makes it a great substance for assessing the melter’s proficiency at busting things apart, since being chemically stable means toluene is not easily changed or altered without some kind of big input, such as a blast of superhigh heat.
Staring through a circular window into the furnace, I see the cherry-red glow of the plasma. It looks like a cross between lava and a supernova. (If you could somehow stick your arm in there, it would be instantly vaporized.)
Back in Arlington, I catch up with Waste Management’s point person for S4, Joe Vaillancourt. After a tour of the gasification plant, he sits on a desk in the operations room. Plastic still covers the gray carpet, but flatscreen monitors are aglow. “This plant will provide the data to quiet the naysayers,” Vaillancourt says. Once it’s running at full capacity, it will process 25 tons of waste a day.
He stares out the window for a moment, past the S4 facility to the man-made mountain of garbage behind it. Then he nods toward the consoles, where technicians will monitor the machines and chemical brew that will blast tomorrow’s trash to smithereens. “If you don’t want landfills, how could you not want this?” he asks.
Contributing editor David Wolman (firstname.lastname@example.org) is the author of The End of Money: Counterfeiters, Preachers, Techies, Dreamers—and the Coming Cashless Society.
30 April 2013
By Ben Messenger
Managing Editor of Waste Management World magazine
Following years of delays preliminary civil works have begun on a waste to energy facility in the village of Venkatamangalam, India which will use gasification technology to process municipal solid waste (MSW) from Tambaram and Pallavaram municipalities, according to a report in The Hindu.
To mark the start of construction, a ‘bhoomi pooja‘ ceremony was reported to have been performed at the 50-acre site located around 15 km from Tambaram in the Indian state of Tamil Nadu.
According to the report the Rs 1 billion ($18.5 million) project a public private partnership which will operate on a design, built, operate and transfer (DBOT) basis and is expected to be complete by mid-2014.
The plant is reportedly been designed to process some 300 tonnes of solid waste per day and generate around 3 MW of electricity from the syngas created by a waste gasification process.
Explaining the plant’s operation municipal officials explained that waste brought to the site would be segregated into biodegradable, recyclable and other inert waste. Wet waste would be dried with blowers to remove moisture and reduce its weight by 50%.
The report said that the waste would then be sieved, shredded and subjected to a thermalisation process to create syngas which would be used to generate electricity.
The by-products from the waste gasification process would be either used for creating ‘eco-bricks’ or dumped in scientific landfills.
According to the report officials claimed that no part of the process would result in any form of pollution to land, water or air.
The facility is reported to be being developed by Mumbai based infrastructure developer, Essel Infraprojects and Tambaram Municipal Solid Waste Private Limited, under a Special Purpose Vehicle (SPV) created for the purpose – Essel Pallavapuram.
According to The Hindu, K.M.R. Nissar Ahmed, Pallavaram’s municipal chairman said that the SPV would also be in charge of operating and maintaining the facility, as well as landfill sites, for 20 years, Mr. Ahmed told presspersons here.
K.M.R. Nissar Ahmed, Pallavaram municipal chairman, said of the total project cost,
Ahmed is also reported to have said that around Rs 200 million ($3.7 million) of the total cost of the facility would be covered by a grant under the Jawaharlal Nehru National Urban Renewal Mission – a huge city-modernisation scheme launched by the Government of India’s under Ministry of Urban Development.
The rest of the funds are reported to have come from Essel Infraprojects, the lead partner in the project.
The chairman is also reported to have said that even after the commissioning the plant, the municipalities of Pallavaram and Tambaram would continue to engage in primary waste collection.
The waste generated and collected in the two towns will be transferred to the plant, with the municipalities paying Rs 500 ($9.30) for every tonne of waste treated at the facility.
Parthapratim Ata, general manager, Essel Infraprojects, was reported to be confident of completing the project on time and begin generating power by the middle of next year
A City That Turns Garbage Into Energy Copes With a Shortage
Trash piled nine yards high is converted to heat and electricity at a waste-to-energy incinerator in Oslo.
Published: April 29, 2013
OSLO — This is a city that imports garbage. Some comes from England, some from Ireland. Some is from neighboring Sweden. It even has designs on the American market.
A trash incinerator. Roughly half of Oslo and most of its schools are heated by burning garbage.
“I’d like to take some from the United States,” said Pal Mikkelsen, in his office at a huge plant on the edge of town that turns garbage into heat and electricity. “Sea transport is cheap.”
Oslo, a recycling-friendly place where roughly half the city and most of its schools are heated by burning garbage — household trash, industrial waste, even toxic and dangerous waste from hospitals and drug arrests — has a problem: it has literally run out of garbage to burn.
The problem is not unique to Oslo, a city of 1.4 million people. Across Northern Europe, where the practice of burning garbage to generate heat and electricity has exploded in recent decades, demand for trash far outstrips supply. “Northern Europe has a huge generating capacity,” said Mr. Mikkelsen, 50, a mechanical engineer who for the last year has been the managing director of Oslo’s waste-to-energy agency.
Yet the fastidious population of Northern Europe produces only about 150 million tons of waste a year, he said, far too little to supply incinerating plants that can handle more than 700 million tons. “And the Swedes continue to build” more plants, he said, a look of exasperation on his face, “as do Austria and Germany.”
Stockholm, to the east, has become such a competitor that it has even managed to persuade some Norwegian municipalities to deliver their waste there. By ship and by truck, countless tons of garbage make their way from regions that have an excess to others that have the capacity to burn it and produce energy.
“There’s a European waste market — it’s a commodity,” said Hege Rooth Olbergsveen, the senior adviser to Oslo’s waste recovery program. “It’s a growing market.”
Most people approve of the idea. “Yes, absolutely,” said Terje Worren, 36, a software consultant, who admitted to heating his house with oil and his water with electricity. “It utilizes waste in a good way.”
The English like it, too, though they are not big players in the garbage-for-energy industry. The Yorkshire-based company that handles garbage collection for cities like Leeds, in the north of England, now ships as much as 1,000 tons a month of garbage — or, since the bad stuff has been sorted out, “refuse-derived fuel” — to countries in Northern Europe, including Norway, according to Donna Cox, a Leeds city spokeswoman.
A British tax on landfill makes it cheaper to send it to places like Oslo. “It helps us in reducing the escalating costs of the landfill tax,” Ms. Cox wrote in an e-mail.
For some, it might seem bizarre that Oslo would resort to importing garbage to produce energy. Norway ranks among the world’s 10 largest exporters of oil and gas, and has abundant coal reserves and a network of more than 1,100 hydroelectric plants in its water-rich mountains. Yet Mr. Mikkelsen said garbage burning was “a game of renewable energy, to reduce the use of fossil fuels.”
Of course, other areas of Europe are producing abundant amounts of garbage, including southern Italy, where cities like Naples paid towns in Germany and the Netherlands to accept garbage, helping to defuse a Neapolitan garbage crisis. Yet though Oslo considered the Italian garbage, it preferred to stick with what it said was the cleaner and safer English waste. “It’s a sensitive question,” Mr. Mikkelsen said.
Garbage may be, well, garbage in some parts of the world, but in Oslo it is very high-tech. Households separate their garbage, putting food waste in green plastic bags, plastics in blue bags and glass elsewhere. The bags are handed out free at groceries and other stores.
The larger of Mr. Mikkelsen’s two waste-to-energy plants uses computerized sensors to separate the color-coded garbage bags that race across conveyor belts and into incinerators. The building’s curved exterior, with lighting that is visible from a long distance to motorists driving by, competes architecturally with Oslo’s striking new opera house.
Still, not everybody is comfortable with this garbage addiction. “From an environmental point of view, it’s a huge problem,” said Lars Haltbrekken, the chairman of Norway’s oldest environmental group, an affiliate of the Friends of the Earth. “There is pressure to produce more and more waste, as long as there is this overcapacity.”
In a hierarchy of environmental goals, Mr. Haltbrekken said, producing less garbage should take first place, while generating energy from garbage should be at the bottom. “The problem is that our lowest priority conflicts with our highest one,” he said.
“So now we import waste from Leeds and other places, and we also had discussions with Naples,” he added. “We said, ‘O.K., so we’re helping the Neapolitans,’ but that’s not a long-term strategy.”
Maybe not, city planners say, but for now it is a necessity. “Recycling and energy recovery have to go hand in hand,” said Ms. Rooth Olbergsveen, of the city’s waste recovery agency. Recycling has made strides, she said, and the separation of organic garbage, like food waste, has begun enabling Oslo to produce biogas, which is now powering some buses in downtown Oslo.
Mr. Haltbrekken acknowledged that he does not benefit from garbage-generated energy. His home near the center of town, built about 1890, is heated by burning wood pellets, and his water is heated electrically. In general, he said, Friends of the Earth supports the city’s environmental goals.
Yet he added, “In the short-term view, of course, it’s better to burn the garbage in Oslo than to leave it in Leeds or Bristol.”
But “in the long term,” he said, “no.”
A version of this article appeared in print on April 30, 2013, on page A9 of the New York edition with the headline: A City That Turns Garbage Into Energy Copes With a Shortage.
C&G Environmental Protection Holdings will invest Bt900 million in its first waste-to-energy plant in Bangkok that can reduce waste by 500 tonnes a day while producing 9.8 megawatts.
Bangkok skies about to get filthier
The Nation April 22, 2013 1:00 am
C&G Environmental Protection Holdings will invest Bt900 million in its first waste-to-energy plant in Bangkok that can reduce waste by 500 tonnes a day while producing 9.8 megawatts.
Headquartered in Hong Kong and listed on the Singapore main board in April 2005, C&G is a leading waste-to-energy investor and operator in China.
C&G invests in, constructs, operates and maintains waste incineration power plants for the treatment of municipal solid waste under the build-operate-transfer investments schemes in China.
The company operates five waste-to-energy plants – Jinjiang, Hui’an, Anxi, Fuqing in Fujian and Huangshi in Hubei – and a sludge treatment plant in Jinjiang. Five more plants are slated to commence operation in 2012-13 – Jianyang and Nanping in Fujian, Langfang in Hebei, Yingkou in Liaoning and Xiaogan in Hubei.
Asia-Pacific’s waste-to-energy market will post substantial growth by 2015, as more countries view the technology as a sustainable alternative to landfills for disposing waste while generating clean energy, according to a report by Frost & Sullivan.
The report said the industry could grow at a compound annual rate of 6.7 per cent for thermal waste-to-energy and 9.7 per cent for biological waste-to-energy from 2008-15. Thermal technologies use heat or combustion to convert both organic and inorganic wastes while biological technologies use bacteria to digest organic wastes to yield fuel.
Ning He, chief executive officer of C&G Environmental Protection (Thailand), said C&G signed a build-operate-transfer agreement with the Bangkok Metropolitan Administration in July last year for the construction of a waste-to-energy project in Nong Khaem in Bangkok, with a total investment of about Bt900 million.
The plant will start up in the middle of next year to eliminate waste in Bangkok by about 500 tonnes per day. The concession will run 20 years. The plant can produce 9.8MW but actual output will be 7-8MW. Part of the electricity will be used by the factories locating in the same area, while the rest will be sold to the Metropolitan Electricity Authority (MEA) under a contract to be signed this month.
“Our revenues will be generated by an elimination fee for the waste in Bangkok, which is at about Bt970 per tonne, as well as by electricity sales,” Ning said.
Under the renewable energy policy governed by the Energy Department, C&G can apply for an electricity subsidy of Bt3.5 per kWh, besides the basic tariff, for the first seven years of operations. Under a policy instituted by the Board of Investment, C&G can apply for a tax-exempt period of up to eight years, and then five years of 50-per-cent tax reduction.
The company will secure financing for the Bangkok project from certain banks in Thailand and all debt repayment will be made in about seven years. The plant will reach its return on investment within 12 years.
The company is also looking to expand from the Thai operations to neighbouring countries starting from Malaysia. It expected to construct two power plants per year, which will require annual investment of about Bt5 billion.
“We chose Thailand as the location for constructing our first waste-to-energy plant outside China as Thailand is one of the most secure locations for foreign investment. The Thai government, however, should grant a clear regulation for alternative energy. Local authorities, such as the Energy Ministry and Interior Ministry, should have a consensus and clear conclusion regarding the policy on waste-to-energy plants,” he added.
Transformation of Waste into Syngas using Plasma Gasification for the Production of Energy or Biofuels
Download PDF : Brian-Thompson-WESTINGHOUSE-PLASMA AA
MILWAUKEE, June 2, 2011 – Alliance Federated Energy (AFE) signs LOI with Novo Energy Pty. Ltd. in Johannesburg to build 3 plasma gasification based energy from waste facilities in South Africa. Under the terms of the agreement, Novo will co-develop the projects with AFE and purchase all the estimated 9-10 million MMBtu’s of syngas expected to be produced annually for their compressed gas vehicle program. The facilities are expected be built in Johannesburg, Cape Town and Durban.
About Alliance Federated Energy
Established in 2005, Alliance Federated Energy is a developer of renewable energy and related infrastructure projects focused on environmentally sustainable technologies, with a specific focus on plasma gasification technology to generate electric and thermal energy and bio-fuels.
About NOVO Energy Pty. Ltd.
NOVO Energy is a South African Energy and Technology Company which has established partnerships with leading international companies that supply alternative fuel technologies and services. This was born out of a need to offer cleaner and more affordable industrial and transportation fuel for the South African market. NOVO is active in Sub-Saharan African countries and provides a turnkey solution – from needs identification to full implementation and maintenance of installed equipment.
NOVO Energy is a level 3 BBBEE contributor. For more information, visit www.novoenergy.co.za.
Reports find waste-to-energy plan feasible
Consultants hired to evaluate the feasibility of the city sewer authority’s $44 million waste-to-energy plan said the project is technically sound but only “marginally” economically feasible.
In a presentation before the Water Pollution Control Authority board, financial consulting firm HDR said the plan to power Stamford’s water-treatment plant through gasification of dried wastewater sludge would eventually net about $2.5 million over a 20-year period. The draft report concluded the project “could provide renewable energy and an economic benefit” to the city, as long as it is “technically feasible and can be successfully completed.”
In a separate report, technical management consultants AECOM said they felt the project was “technically feasible as defined,” adding that gasification technology “holds great promise in reducing energy use at wastewater treatment facilities and has the potential of reducing the overall environmental impact” of such facilities.
Gasification is a process for extracting energy from organic materials by heating the material at high temperatures with oxygen or steam. Though the method was first developed in the 1800s and has since been used on an industrial scale to produce electricity using coal or wood, AECOM said Stamford’s project is the first it is familiar with that would try to produce power through gasification of biosolid waste.
The WPCA hired financial and technical consultants to review the waste-to-energy plan last year after it came under criticism from city residents who said Stamford should not be spending millions on an untested technology.
Under the proposal, the WPCA would first substitute wood chips for natural gas to fuel its current waste sludge drying system, which produces “biosolid” pellets the city sells to a contractor as fertilizer. In a second phase, the sewer authority plans to install generators that would run on energy produced from gasification of the pellets, providing fuel for the plant’s overall waste-treatment operation.
Despite the generally positive evaluations, critics of the plan who pushed for the reviews said they are still wary of the project. Lou Basel, a WPCA board member and vocal waste-to-energy critic, said he felt the AECOM report had many holes in it.
“When we went through it, it had many, many instances where AECOM said there’s information missing on this, information is missing on that,” Basel said.
“I said, ‘How could you state that the project is technically feasible if all this information is missing?’ ”
WPCA Executive Director Jeanette Brown said the reports were encouraging.
“AECOM is very positive that the project is technically feasible,” Brown said. “That gives me a lot of confidence if a big company like AECOM is promoting gasification to their clients as a viable technology.”
Brown said grant funding and changes, such as skipping the project’s first phase, could make it more economically palatable. HDR management consultant David Traeger said the estimated $2.5 million gain is not enough to justify the investment on a financial basis, especially as operating costs and other risk factors could rise. However, gasification could provide valuable noneconomic benefits, he said.
“Any environmental project is probably going to cost money, so you need to look at the sustainability over the long haul too,” Traeger said. “There’s more than one aspect to evaluating feasibility than just financials.”
HDR Vice President Kurt Emmerich said state and federal air-pollution regulations will almost certainly become more restrictive in coming years, meaning that creating a sustainable treatment plant that can reuse waste rather than truck it to an incinerator is likely to become an asset. In that respect, Brown, who has spearheaded the project, is moving in the right direction, Emmerich said.
“Jeanette is leading you into something that is scary, and there are some uncharted waters, but she’s leading you where it’s going to be in the future,” Emmerich told the WPCA board.
Yet Cove resident Marikay Mead Wilson said she was still skeptical after seeing the presentation.
“It sounds like there are many unknowns, a lot of questions, and it sounds kind of half baked,” Mead Wilson said. “We can’t be the guinea pigs. We can’t afford to do this wrong.”
16 April 2013 | By Marino Donati
Plans to develop an advanced gasification energy from waste facility in the Midlands have been launched.
Waste2Tricity (W2T) is overseeing a concept design study to produce proposals for the facility that would convert around 100,000 tonnes of residual household and commercial and industrial waste to provide almost 109,000 MW hours of electricity every year.
The exact location has yet to be revealed but a planning applicaton is scheduled for the summer
The project will use Westinghouse plasma assisted gasification from Alter NRG. It will use internal combustion engines, but is also expected to demonstrate AFC Energy’s alkaline fuel cells (pictured, left), as they become commercially available.
W2T chairman Peter Jones said he expected it to be the first of many similar programmes for its project partners.
He said: “The 100,000 tonnes a year model will meet the localism agenda, using locally derived feedstock to supply electricity to local homes and businesses. We believe there is a potential market in the UK for up to 100 units of this size.
“Once we are able to deploy fuel cells, the output from our plants will increase substantially and be carbon capture ready, holding out the prospect of carbon negative electricity.”
It is hoped the plant will be operational in late 2016.
Gasification – Carbon negative SNG from waste, biomass and coal: a cost-effective way to decarbonise gas-fired generation.
By A. R. Day, cost consultant; A. Williams, GL Noble Denton Ltd; Chris Hodrien, Timmins CCS Ltd.
Low cost carbon negative SNG (substitute natural gas) produced from co-gasified waste, biomass and coal, and decarbonised at source prior to injection into the gas transmission system, will assist in decarbonising downstream gas users – power, heat, transport and industry – at no cost to businesses and consumers, without alteration to their existing use of energy, provided that carbon negative SNG is cost competitive with fossil natural gas.
Particularly attractive is the integration of SNG production technology initially developed by British Gas Corporation and the UK government as part of a plan to supply the whole of UK gas demand by SNG (when North Sea gas ran out) with BGL multi-fuel co-gasification (as demonstrated by the SVZ company operating what was once Europe’s largest lignite to town gas production plant, at Schwarze Pumpe in former E. Germany), together with the Timmins CCS concept.*
The basic idea (Figure 1) is to use high efficiency slagging co-gasification to produce carbon negative synthetic natural gas with CCS. The low cost carbon negative SNG, with gas storage, and natural gas back up, is used in a conventional natural gas fired combined cycle plant with no loss of efficiency or operational flexibility.
The cost per unit energy of carbon negative SNG is estimated to be between 1/10th and 1/15th of the ‘whole system’ cost of wind power, and produces lower emissions than wind when emissions from fossil fuel back up are taken into account.
The carbon negative SNG scheme can also be extended to include integrated electrolysis, powered by low cost excess wind ‘lopping’, to produce ‘green’ hydrogen, oxygen and heat for low cost demand management and energy storage (see Figure 2).
For the main carbon negative SNG scheme discussed here, the following results have been obtained:
– Plant scale: 1.0 to 1.5 million tonnes per annum of nominally 50% mixed wastes, 30% biomass and 20% coal by mass.
– Gross efficiency, for carbon negative SNG: 78.5%.
– Net efficiency for carbon negative SNG, allowing for parasitic plant loads: 76.75%.
– Net fuel cost: £-0.4/GJ.
– Carbon content of fuel: 54.6% biogenic, 45.4% fossil carbon.
– Payback period: 20 years, 8% weighted aggregate cost of capital.
– Cost of 60 bar carbon negative SNG: 40 to 45 p/therm.
– Implied cost of carbon negative SNG fired power generation: £40 to 50/MWh.
– Cost of 150 bar high purity supercritical CO2: £0.4 per tonne CO2 excluding transport and storage.
– Cost of CO2 transport and storage: 33% of the unit cost of CO2 transport and storage per unit energy output compared with a fossil fuel power station.
– Net emissions intensity: -45 gCO2/kWh, assuming carbon negative SNG is used in a 60% efficient CCGT.
Decarbonising gas turbine based generation
Natural gas fired combined cycle plants are the thermal generation technology of choice in most of the Western world due to the combination of: flexible operation; high efficiency; low emissions; low capital cost; readily available fuel supply system; low land take; and low water consumption. However, fitting post-capture CCS to a natural gas fired CCGT significantly compromises many of those advantages.
Our approach is to decarbonise gas at source, prior to its injection into the gas grid, thus enabling existing CCGT operators to generate decarbonised electricity with no loss of: energy efficiency; plant load factor; operational flexibility; or rate of capital recovery. This highly attractive proposition depends on the cost of carbon negative SNG being competitive with the cost of fossil natural gas.
Methane is the simplest and most common hydrocarbon gas, and is the world’s most highly developed, internationally traded, fungible and storable gaseous energy resource and vector. But methane is not necessarily a fossil fuel. The fossil CO2 emissions intensity of methane used for energy purposes depends on what fuel the methane is made from, how it is made, and the end use. Fossil CO2 emissions from the use of methane can be negated by a combination of partly biogenic carbon fuels and CCS (Figure 3).
A typical mixed waste stream contains around 65% biogenic carbon. A typical 50% mixed residual waste, 30% biomass and 20% coal fuel mix contains 50 to 55% net biogenic carbon (as a proportion of total carbon). A typical methanation plant produces nearly 55% of total carbon throughput as CO2, which is available for sequestration, and 45% as methane. Emitted biogenic carbon, and sequestered fossil carbon are accounted as carbon neutral. Sequestered biogenic carbon is accounted as carbon negative, and offsets fossil carbon emissions at the SNG’s final point of use. The biomass is assumed to be sustainably resourced. Residual waste has already had at least one economic use, and any emissions associated with the original materials processing and use are assumed to have been accounted for in the original use. Residual wastes are those wastes left after waste reduction reuse and recycling, for which there is no further economic use.
Methane synthesis is an attractive route to delivering low cost CCS. SNG plants are inherently carbon capture ready as they produce CO2 as a waste byproduct. Compared with fossil fuel power stations, SNG plants produce relatively low volumes of high CO2 partial pressure mixed SNG and CO2, and can be converted economically to CCS. This has been demonstrated at the Great Plains synfuel plant in Dakota, since 1984 the world’s largest and longest-running SNG plant, which was retro-fitted in 2000 with CO2 capture and pipeline compression for EOR at Weyburn in Canada. The carbon negative SNG with Timmins CCS scheme discussed here uses the same British Gas developed catalysts as at Great Plains.
Reducing the cost of CCS
CCS installed on fossil fuel thermal power generation is currently uneconomic due to the high cost of CO2 capture and compression from power station flue gases. This is the largest single impediment to the large scale deployment of CCS on power generation. On the other hand, CCS on gas based processes is already economic, and in use at commercial scale.
The solubility of gaseous CO2 in a liquid solvent carrier is proportional to the concentration of CO2 in the original mixed gas stream, and the pressure of the gas stream. Concentration x pressure = partial pressure. CO2 partial pressure is thus the ‘key’ determinant of the capital and operational cost of CO2 separation and compression.
The IEA recently stated “The higher the CO2 partial pressure, the greater the ease of capture, and the lower the cost per tonne of CO2 captured and stored.” At the point of CO2 separation, and for the same plant energy input, the gas flow rate in an SNG plant with Timmins CCS is 400 times less, and the CO2 partial pressure is 250 times greater, than in a post-combustion fossil fuel power plant. This is a massive engineering, operational and financial advantage and explains why the cost of CO2 capture and compression from an SNG plant is two orders of magnitude lower than for post-combustion CCS on a fossil fuel power station. See Figure 4.
Reducing the cost of producing SNG from coal
80% of the unit cost of SNG is the cost of fuel and the cost of capital. Both may be reduced by improving net process efficiency. The 1955 to 1992 UK government/British Gas Corporation ’30 Year plan’ to produce SNG from coal to supply the whole of UK gas demand when North Sea gas ran out remains the world’s highest efficiency coal to SNG scheme, at 76% net efficiency unabated.
This compares with 61% net efficiency in the recently published US DOE/NETL Worley Parson coal or lignite to SNG scheme, with the option of fertiliser co-production. The British Gas scheme delivers 25% more SNG per tonne of coal than the DOE/NETL scheme.
The technology was successfully demonstrated at the British Gas SNG development plant at Westfield prior to its closure in 1992.
The high efficiency of the British Gas SNG scheme is achieved by integrating the BGL slagging gasifier, the world’s highest cold gas efficiency industrial scale solid fuel co-gasifier (Figure 5), and the HICOM combined catalytic shift and methanation process, with a range of standard industrial gas cleaning processes: Rectisol pre-wash, COS hydrolysis, Selefining, Claus/Scot and Selexol.
Both the BGL and HICOM rely on internal mass and energy exchange thus enabling the energy released by the oxidation of carbon to be used efficiently to transfer hydrogen bonds with oxygen in steam to hydrogen bonds with carbon in methane.
Some of the processes are endothermic, and some are exothermic. Highly developed waste heat recovery producing 540 deg C 155 bar steam drives on-site power supply, air separation and a range of plant processes. Increasing the gasification pressure increases methane production, decreases tar production, increases overall plant efficiency and reduces capital costs per unit output. A high pressure BGL was operated at 65 bar pressure at Westfield in the late 1980s.
Reduced operational costs with Timmins CCS
Integrating the use of partly waste based fuels and Timmins CCS (Figure 6) with HICOM and Selexol acid gas removal increases the efficiency of the base BGL, HICOM and Selexol processes. Plastic in the waste increases methane production in the gasifier, thus reducing the load on the methane synthesis process.
The recycling of part of the CO2 stream to HICOM reduces the amount of product gas recycled for cooling purposes. It also assists in suppressing the Boudouard reaction (2CO = C + CO2), thus reducing the need to inject excess steam to suppress Boudouard, and subsequently to remove the steam prior to gas separation.
Cryogenic separation of part of the CO2 stream prior to Selexol, and maintaining the gas flow at high pressure, reduces the capital and operational costs of the base Selexol plant. The improvements in efficiency in the base HICOM and Selexol plants offset the efficiency penalty for the Timmins CCS cryogenic plant.
A carbon capture ready SNG plant with the Timmins CCS process produces high purity ambient temperature liquid CO2 at 60 bar. In order to convert the plant to fully abated CCS state, it is only necessary compress the already liquid CO2 to 150 bar supercritical state. This requires the addition of a small liquid CO2 pump with only 0.06% net energy penalty and 0.2% CAPEX penalty. This explains the exceptionally low marginal abatement cost of carbon for the carbon negative SNG scheme with Timmins CCS.
Building on waste gasification experience, the key to viable economics
The big question is: can carbon negative SNG be produced at a price which is competitive with fossil natural gas? Some 80% of the levelised cost of SNG is CAPEX recovery and fuel costs. The answer is “yes” if waste gasification is factored in.
Our work has concentrated on reducing fuel costs by using waste as the primary fuel, with biomass and coal as the secondary fuels.
The basic physics and chemistry of modern high pressure gasification were developed before WW1. The first commercial coal fuelled dry ash Lurgi gasifier was built in the late 1930s. The first pilot oxygen blown slagging Lurgi gasifier, designed to run on Italian lignite, was built in 1943. Its existence was disclosed to allied intelligence in Frankfurt in April 1945 and reported to the UK government Ministry of Fuel and Power in 1947. The slagging gasifier used less steam than the dry ash gasifier, and could operate on low grade fuels. The UK government reported in 1947 than the cost benefit of using low grade fuel had to be balanced against the cost of oxygen.
A second pilot slagging Lurgi gasifier was built in Germany in 1953. The joint rights to the design were acquired by the UK Ministry of Fuel and Power in 1955. From 1955 to 1992 the British Gas Lurgi (BGL) slagging gasifier was developed in the UK, first at the Midlands Research Station (MRS) in Solihull, and latterly at the Westfield development centre.
Use of waste as a low cost substitute fuel was first considered at MRS in the early 1970s, and some low key experiments were carried out. In the late 1980s British Gas assisted the East German state run town gas plant at Schwarze Pumpe with experiments using a converted dry ash Lurgi gasifier, fitted with a slagging hearth, to co-gasify a 50/50 waste/coal mix.
From 1990 onwards the design of a commercial scale BGL gasifier, using operational data from Westfield, resulted in full environmental consent being granted in 1998 for the use of the BGL to co-gasify several hundred different classifications of hazardous and non-hazardous wastes at Schwarze Pumpe, at up to 85% waste/15% coal. Commercial operations commenced in 2000. The plant was dismantled in 2007, and is now in India awaiting re-erection as a lignite to fertiliser plant.
Typically the BGL at Schwarze Pumpe ran on a 75 to 80% mixed wastes/20 to 25% mixed coal and lignite feed stock. Test runs in 2003, supported by the European plastics industry (Tecpol), indicated stable operation on 80% mixed wastes/20% coal fuel mix.
A changing economic landscape for waste
The combination of landfill tax, various incentives for the use of renewables and the carbon floor price have revolutionised the economic landscape in the UK for waste, biomass and coal co-gasification, when combined with low cost CCS. We believe that the BGL is the world’s highest net efficiency, and most operationally flexible, large scale gasifier capable of handling high waste content fuels and biomass.
In many parts of the world, residual waste (after reduction, recycling and re-use) is the most widely available and lowest cost sustainable indigenous fuel resource, but burning waste in a moving grate incinerator to produce low grade steam for base load power generation at around 25% net efficiency is expensive and inefficient. In comparison the British Gas originated SNG scheme with Timmins CCS can produce carbon negative SNG, which is a storable and dispatchable energy commodity, at 76.75% net efficiency, ie three times more ‘bang for your buck’.
Due to the far higher net energy efficiency, the capital cost per unit output energy of a waste gasification plant is lower than for a waste incinerator.
Around 34% of a waste incinerator’s mass throughput is produced as solid, liquid and gaseous emissions requiring expensive flue gas clean up, and secondary hazardous or leachable waste processing and disposal operations.
Coal and waste are both dirty hydrocarbon fuels. High temperature oxygen blown ‘clean coal’ slagging gasification technology, designed to co-vitrify the heavy metal and minerals in low grade coal or lignite is equally applicable to waste processing, and massively reduces the secondary waste processing problems associated with waste incineration. Indeed the BGL slagging gasifier can utilise the hazardous air pollution control residues produced by waste incinerators as a flux to promote slag formation.
As already noted, the BGL gasifier at SVZ Schwarze Pumpe (Figure 7) was granted full environmental certification in 1998 to co-gasify up to 85% mixed hazardous and non-hazardous wastes, and 15% coal, and was approved by UNEP in 2006 for the highly efficient (99.99%) permanent destruction of persistent organic pollutants. Hazardous heavy metals are immobilised in a certified non-leaching vitrified recyclate.
Coal to SNG is not economic in Europe or USA due to the low price ‘spread’ per unit energy between coal and natural gas being insufficient to cover the capital cost of an SNG plant. SNG developments are proceeding apace in China due to the large ‘spread’ between the low cost of stranded coal assets in western China, and the high cost of gas on the eastern China seaboard. Gas pipelines are the lowest CAPEX method of bulk energy transmission. There is already experience with BGL and SNG production in China, see Figures 8 and 9.
The Great Plains synfuel plant is commercially viable due to a combination of: low cost mine-mouth lignite as fuel; economic co-production of SNG, power, fertiliser, phenol and CO2 for commercial EOR at Weyburn in Canada; and the low capital recovery rate for federal funds invested in the project. Our concept is to increase the price ‘spread’ between solid fuels and natural gas by using waste as a low cost fuel to displace a large part of the coal supply.
In order to reduce the use of landfill for waste disposal, many countries tax the use of landfill from waste, and incentivise the production of ‘clean’ energy from waste. The UK landfill tax escalator runs until 2015, then is flat to 2021, with proposed inflation indexation from 2021 to 2028. The 2015 landfill tax will be £80/tonne. Assuming a typical mixed non-hazardous waste stream contains an average of 10 GJ/tonne of thermochemical energy, the avoided cost of landfill tax is an effective £-8/GJ fuel subsidy. This can be used to offset the typical UK cost of coal and biomass at around £3.0 to 3.50/GJ. Using an average 50:30:20 waste, biomass, coal (by mass) fuel mix as a basis, combined with processing of hazardous air pollution control residues produced in waste incinerators, it is possible to devise a net negative cost fuel mix with nearly 55% biogenic carbon content.
A strong case in the UK, EU and elsewhere
Our analysis shows that under a range of feasible policy scenarios, during the period 2012 to 2030, a carbon negative SNG plant in UK, with a fuel input of around 1.0 to 1.5 million tonnes pa (660 to 1000 MWt fuel input) of mixed fuels will produce carbon negative SNG at a cost of around 40 to 45 p/therm, based on a 20 year payback period and 8% weighted aggregated cost of capital.
The cost of carbon negative SNG in the UK case includes the avoided cost of UK landfill tax, the avoided cost of the UK carbon floor price, and a substantial developer’s risk premium, but excludes the additional revenue from the Renewable Heat Incentive (RHI) until 2031, currently 104 p/therm for 54.6% biogenic carbon content SNG.
The current open market wholesale price of natural gas in the UK is around 65 p/therm. This is expected to increase to around 70 p/therm by 2015, and then gradually decrease from the mid 2020s onwards. There is considerable debate about the long-term price trajectory for gas in EU and UK. It depends on, among other things, the rate at which conventional gas is supplemented by unconventional gas, and the impact this has on long-run oil-indexed gas prices. Informal advice from parties associated with shale gas development in the UK suggests that a technically and financially robust scheme, which is cost competitive with the long-term price trajectory for gas of around 40 to 45 p/therm, is considered to be ‘bankable’.
The UK CCS cost reduction task force recently reported that by 2030 the cost of power generation with “conventional” CCS might feasibly be reduced from around £160/MWh to around £100/MWh base load (8000 hours pa), the cost of sequestered carbon reduced from around £150/tonne to about £50/tonne, and the rate of CO2 capture increased from 85% to 90%.
Over the same period, and using the same assumptions as the task force, the cost of power generation from carbon negative SNG would reduce from £55/MWh to £40/MWh, the cost of sequestered carbon would reduce from £15/tonne to £3/tonne, with the equivalent of 110% CO2 capture rate. Even allowing for optimism bias, and discounting any benefit from the RHI, there is a strong case to be made for developing carbon negative SNG in the UK, and elsewhere in the EU.
There is also a strong case to be made for developing low cost carbon negative SNG with Timmins CCS in a number of countries (eg, USA, China, S Korea, Japan as well as in the EU) as a means of economically supplementing natural gas resources, addressing the problem of ever increasing production of hazardous and non-hazardous wastes, and reducing atmospheric emissions. The specific circumstances of each country would of course need to be taken into account when developing any particular scheme.
*This article draws on the presentation given by Dr Williams at the IChemE Gasification Conference in Cagliari, Sardinia, May 2012. It also follows on from the article on Timmins CCS published in the January 2013 edition of Modern Power Systems.
Timmins CCS is a generic CO2 separation scheme for any gas flow above 10 bar pressure, using rearranged standard gas processing plant. In the Timmins CCS scheme the whole plant operates at high pressure, thus avoiding de-pressurisation and re-pressurisation costs, and producing high purity high pressure liquid CO2. Timmins CCS may be integrated into a wide variety of power generation, gas processing, reforming, urea and petrochemical plants where it is desired to separate CO2 as a high purity, high pressure liquid.
Three different schemes, based on three different fuels, using the Timmins CCS process for gas turbine power generation, are currently being developed:
– Waste, biomass and coal: co-gasification with CCS to produce carbon negative SNG (as described in the present article), currently, the most advanced development of Timmins CCS.
– Coal: IGCC with CCS and a hydrogen fired CCGT. This was the topic of the January 2013 article in MPS. An update is planned, reporting on the latest results, which are greatly improved relative to those published previously.
– Natural gas: partial oxidation (POX) with autothermal reforming with a dual fuel high-hydrogen syngas/natural gas fired CCGT. Energy is recovered from the hot gases produced by the POX reactor in an expansion turbine prior to further reforming, CCS and the CCGT. The additional energy recovered by the expander turbine offsets the energy losses in the reforming stages.