Source: http://energy.cleartheair.org.hk/?m=201208
Timestamp: 2019-04-21 00:18:02+00:00

Document:
China BlueChemical, the fertiliser manufacturing unit of state-owned oil and gas major China National Offshore Oil, plans to make a complete switch from natural gas to coal to power its urea plant in Inner Mongolia by 2015, to ensure the plant stays viable amid rising gas costs.
Chief executive Yang Yexin said the plant would have problems making a profit if gas prices rose another 20-30 per cent from present levels .
“In the long term, gas prices are bound to go up, so we need to plan ahead to ensure sustainability of the plant,” Yang said.
Beijing is under pressure to lift domestic gas prices since more gas has to be imported to meet demand, and international gas prices are much higher than regulated domestic prices.
The Tianye plant makes urea, a nitrogenous fertiliser, which together with phosphate and potassium, are the three key ingredients in a balanced fertiliser mix.
The plant also makes methanol, which is an industrial chemical and fuel.
Urea output at the plant fell 4 per cent and methanol production decline 16 per cent in the first half from the year-earlier period, due to a shortage of gas.
Yang said gas supplier PetroChina (SEHK: 0857, announcements, news) would complete a second pipeline in the region this winter, which would ease the supply shortage.
At China BlueChemical’s Hainan plant, its main base, output also tumbled 16.6 per cent and methanol production slid 7.6 per cent in the first half, due to planned maintenance of facilities. Yang said production volumes should return to normal as no overhauls of major facilities were planned for the second half, and major maintenance checks tended to take place once every two to three years.
Declines in output and sales were more than offset by the benefits from a 11.5 per cent rise in the average urea selling price; and a 4.3 per cent gain in the methanol selling price, resulting in a 5.1 per cent gain in overall first-half sales.
However, due to lower sales volumes, the firm’s fixed costs were higher on a per-tonne basis, squeezing its profit margin to 30.4 per cent from 35.7 per cent in the same period last year. Net profit dropped 11.8 per cent year-on-year to 908.45 million yuan.
On Tuesday Mayor Michael Bloomberg announced New York City’s solicitation for proposals to construct a waste-to-energy facility near or within New York City, a decision that reflects the mayor’s intention, announced in the 2012 State of the City address, to “explore the possibility of cleanly converting trash into renewable energy.” The proposed facility will be a pilot program, processing at most 450 tons of waste per day but capable of doubling capacity if successful. According to the mayor’s press release, conventional incineration facilities are excluded from consideration, limiting eligible proposals to emerging waste-to-energy technologies. The mayor is seeking jobs, energy independence, reduced greenhouse gas emission and—most importantly—reductions in the city’s solid waste management costs. The city currently spends about $1 billion per year to manage solid waste—a cost that is certain to grow as landfills in the United States close.
To realize these goals, however, the city must confront the challenges of siting such a facility in one of the city’s 59 neighborhoods, which have consistently and often successfully fought new solid waste facilities for over two decades. Any proponent of a new waste-to-energy facility may also need to navigate the state’s new licensing process for electric generating facilities, which is expected to become applicable this year after implementing regulations are finalized.
At one time, New York City relied on 32 municipal waste incinerators and at least 35 municipal landfills to manage its solid waste. Those facilities were phased out beginning in the 1960s, and by 1994 there were no incinerators and only one landfill remaining in five boroughs. Bucking this trend, however, in 1979 Mayor Ed Koch proposed the construction of a new incinerator at the Brooklyn Navy Yard. Community groups successfully fought this proposal until 1996, when Mayor Rudolph Giuliani signed a bill prohibiting construction of the Navy Yard incinerator and requiring closure of Fresh Kills Landfill on Staten Island—the last in the city.
Since the closure, almost all the city’s commercial and residential waste has been trucked to out-of-state landfills at great financial and environmental expense. The city’s 2006 Solid Waste Management Plan (SWMP) tried to expand the options for handling waste by planning for more recycling, composting and out-of-state shipment by barge rather than truck. But New York City and its private waste haulers continue to truck the vast majority of the city’s waste to out-of-state landfills.
During the course of the Navy Yard Incinerator debate, the regulatory landscape for incinerators changed. In the early 1990s, Congress and the Environmental Protection Agency (EPA) drastically curtailed allowable incinerator emissions. This rule change helped bring about a 96 percent reduction in mercury emissions between 1990 and 2005 and a 99 percent reduction in dioxin emissions.
The U.S. Supreme Court also resolved the issue of “toxic ash” from incinerators in 1994. Prior to 1994, incinerators had relied on the household waste exemption in the U.S. Resource Conservation and Recovery Act (RCRA) when disposing of incinerator ash. But the Supreme Court held that incinerator ash with hazardous waste characteristics must be disposed of as hazardous waste in accordance with RCRA. The environmental concerns that surrounded the 1985 proposal may therefore no longer be valid.
While nearly all existing waste-to-energy facilities in the United States create electricity by burning waste, emerging technologies provide alternative electricity production methods. Thermal processes (e.g., gasification and plasma) involve heating the waste to release gases that are then burned to create electricity. Separating the solids from the gases prior to combustion eliminates most ash and other particles from the exhaust. Anaerobic digestion uses municipal waste as a food source for microbes that thrive in oxygen-free environments, converting organic waste into methane gas, among other things, which is then burned to generate electricity. Hydrolysis involves immersing the waste in acid to create sugars that can then be fermented to produce ethanol, which can be sold or used as fuel for energy production.
Each of these emerging technologies further reduces the potential for adverse environmental effects. And they are arguably consistent with the state’s solid waste management policy, which creates a hierarchy of solid waste management methods that include, from most to least preferable: (1) reduce waste; (2) reuse or recycle or compost; (3) recover energy from solid waste that cannot be reused or recycled; and (4) landfill or burn. New York City’s current SWMP concluded that it was not a realistic alternative to site, permit and build a new commercial-scale waste conversion facility in the New York City region in the near term of the next five years. The city’s next SWMP is due in 2016 and, based on recent statements from local officials, is likely to re-visit this conclusion.
The state’s renewal of Article 10 of the Public Service Law in 2011 will both help and hurt the effort to site a waste-to-energy facility in New York City. From 1992 to 2003, Article 10 created the exclusive process for licensing electric generating facilities of 80 megawatts or more in New York State. The Siting Board of the Public Service Commission oversaw the process and issued certificates of public need and necessity to successful applicants. The board had the authority to waive compliance with other state and local requirements and permitting processes on a case-by-case basis. Facilities that generated fewer than 80 megawatts (MW) were subject to normal state and local approval processes, however, including the State Environmental Quality Review Act (SEQRA) and local zoning. When Article 10 expired in 2003, SEQRA, zoning and other state and local laws applied without restriction to all power plants—a development that many municipalities and residents welcomed.
Since the existing waste-to-energy facilities in New York are each below the 80 MW threshold, Article 10 would not have applied to them. The prior version of Article 10 also contained an exemption for facilities that generated electricity from solid waste—an exemption conspicuously lacking in the 2011 version. Whether the amended Article 10 will apply to a new waste-to-energy facility depends on its size and use of its electricity. Article 10 applies to all new facilities with a nameplate capacity of 25 MW or more that sell power to the electricity grid. At least a few of the 10 existing waste-to-energy facilities in New York meet this threshold. Even a relatively small conventional waste-to-energy facility processing as little as 1,000 tons per day would likely be subject to Article 10.
On the positive side for new electric-generating facilities, Article 10 is intended to provide a streamlined review process with four phases: the formalized pre-application phase, the application phase, the administrative hearing and the decision. Identification of environmental or health effects, mitigation of those effects, and reasonable alternatives must all be identified in the pre-application phase. The process is intended to address all legal and environmental issues and stakeholder concerns in one forum overseen by the siting board constituted for the particular application.
On the challenging side, Article 10 requires a heightened consideration of environmental justice (EJ), community impacts and alternatives. Unlike SEQRA, which requires disclosure but not necessarily action on environmental justice, Article 10 requires proponents to avoid, offset or minimize impacts on EJ communities through “verifiable measures.” Article 10 also requires a full exploration of alternative locations and solid waste management options (i.e., continued landfilling and recycling). In addition to the alternative proposed by the applicant, the intervenors or the siting board may also propose alternatives, and the siting board may make a preliminary finding on the adequacy of the consideration of alternatives before addressing other issues.
One recent event is a potent reminder of challenges that waste-to-energy will face inside or outside the new Article 10 process. In 2011, the commission received an application to add waste-to-energy facilities to the list of projects that qualify as “renewable” under the state’s renewable portfolio standard, which calls for the New York State Energy, Research & Development Authority to help the state produce 30 percent of its energy from renewable sources by 2015. The commission promptly received thousands of comments in opposition, and the application was withdrawn on Dec. 8, 2011.
Successfully siting a waste-to-energy facility will involve conducting a rigorous environmental impact review; choosing the proposed location carefully; and building strong community support. Year after year, New York courts reject legal challenges to projects where a complete environmental impact statement has been prepared under SEQRA. This includes solid waste management facilities like the proposed waste-transfer station on the East River at East 91st Street, which residents repeatedly and unsuccessfully challenged in court. New York courts are likely to be deferential to electric generating facilities where they feel that a thorough environmental review has taken place whether pursuant to SEQRA or Article 10.
With regard to location, Article 10, once effective, will bar municipalities from separately regulating electric generating facilities. But local laws still matter—a lot. Applicants must demonstrate to the Public Service Commission whether and how a proposed facility will comply with local laws or, if not, why the commission should permit exceptions. Moreover, municipalities are mandatory participants in the hearing process.
The New York State Department of Public Service has recently released its draft of Article 10 regulations for public comment and they underscore the important role that members of the public and municipalities will play in the commission’s review process. Selecting a site where waste-to-energy facilities would be as-of-right (if possible) is therefore recommended. Applicants should also consider choosing a brownfield site, which may provide access to tax credits offered through the New York State Brownfield Cleanup Program. If Article 10 does not apply to the facility, local laws will govern. In New York City, this may include compliance with the City Environmental Quality Review (CEQR) regulations and the CEQR Technical Manual, the Uniform Land Use Review Procedure (ULURP), and Fair Share regulations (which seek equity among neighborhoods in siting municipal facilities). Most important, the facility will be subject to local zoning controls.
In New York City, siting will be complicated by the dwindling number of manufacturing zones. In the past 10 years, the City Planning Commission has undertaken extensive (and in some cases long overdue) zoning changes in industrial areas to eliminate some “M” zones and open up vast areas to residential and commercial uses. The result is a 20 percent reduction in dedicated manufacturing zones in New York City. This figure does not account for the ad-hoc erosion of industrial zones where the city has allowed a large number of new parks and residential uses to be sited in the past 10 years.
With fewer dedicated manufacturing zones and more mixed use districts, siting heavy industrial facilities has become tougher. According to the Waste-to-Energy Research and Technology Council, housed at Columbia University, facilities ideally require 25 acres to accommodate truck queuing within the project site. With the exception of the west shore of Staten Island, this is likely to be a challenge in New York City. It also suggests that waterfront sites that can accommodate barge transport and minimize truck traffic will have preferential treatment.
Finally, proponents must develop strong plans for building community support. Article 10 creates a formal role in the review process for residents within five miles of a proposed facility and certain nonprofit organizations. And the amended Article 10 preserves the “intervenor account” that is paid by the applicant to defray costs incurred by municipalities, nonprofit organizations and municipalities in participating in the review process. If the facility is under 25 MW, local laws—particularly ULURP and Fair Share—provide their own process for seeking community input and developing project alternatives.
Addressing valid community concerns is therefore vital. One way to accommodate such concerns is through “community benefit agreements,” which are typically negotiated outside the formal permitting processes with key community stakeholders and elected officials. These agreements can be highly controversial and are largely untested in courts, but they remain a regular part of development in New York and will likely play a key role in developing community support for a waste-to-energy facility.
The deep public concerns about waste-to-energy facilities are rooted in a history of incinerators that is admittedly ugly. But modern waste-to-energy facilities are dramatically cleaner than their pre-1992 predecessors and air emissions even compare favorably to fossil-fuel power plants. These facilities also reduce emissions from truck traffic and landfilling, which will have regional environmental benefits.
A key critique, that waste-to-energy facilities will reduce the city’s incentive to increase recycling, may prove unfounded. Europe has at least 400 waste-to-energy facilities and local recycling rates that are often above 50 percent. The biggest challenge for new facilities is likely to be the identification of an industrial site that is appropriate for a waste-to-energy facility (if not zoned for it) and that satisfies the state’s rigorous new standards for environmental justice.
Christopher Rizzo is counsel and Michael Plumb is an associate at Carter Ledyard & Milburn in its environmental and land use practice group. Mr. Rizzo teaches at Pace Law School.
Reprinted with permission from the March 8, 2012 edition of the New York Law Journal © 2012 ALM media Properties, LLC. All rights reserved. Further duplication without permission is prohibited. For information, contact 877-257-3382, reprints@alm.com or visit www.almreprints.com.
 The comment echoed similar statements by the City’s Director of Sustainability and Long Term Planning at an Oct. 24, 2011 City Council Hearing.
 New York City, PLANYC, p. 137 (April 2011).
 42 U.S.C. §7429(a)(2) (1990 Clean Air Act Amendments requiring NSPS for new incinerators and MACT for existing sources); regulations promulgated at 60 Fed. Reg. 65387-65436 (Dec. 19, 1995).
 Memorandum from Walt Stevenson, EPA Office of Air Quality Planning and Standards, on Emissions From Large and Small MWC Units at MACT Compliance (Aug. 10, 2007).
 Chicago v. Environmental Defense Fund, 511 U.S. 328 (1994).
 WTE facilities are likely to do well in a greenhouse gas analysis because, municipal solid waste is composed of renewable fuel which will displace fossil fuels in energy production. In addition, landfill methane gas is avoided. If greenhouse gas reductions become a marketable commodity in the United States, WTE facilities could generate carbon credits.
 N.Y. Envtl. Conserv. L. §27-0106.
 Emerging solid waste technology facilities were evaluated in a separate study which was attached as an appendix to the SWMP. New York City Comprehensive Solid Waste Management Plan,Appendix F (September 2006).
 DEC released draft environmental justice regulations in January 2012. Among other things, the regulations require a study area of ½ square mile around the proposed major electric generating facility.
 New York State Public Service Commission, Proceeding 03-E-0188.
 N.Y. Public Service L. §172.
 Pratt Center for Community Development, “Protecting New York’s Threatened Manufacturing Space,” April 16, 2009.
 N.Y. Public Service L. §166(m).
 N.Y. Public Service L. §163; N.Y. Finance L. §97-kkkk.
There are nearly 8 million people crammed into Israel and most of them like a little A/C in the summer. But only 74, 520 families separate their organic and inorganic waste. What does that have to do with anything, you ask?
Well, it turns out that the Ministry of Environment has recently committed just over USD17 million to help biogas innovators turn organic waste into energy within the next three years. Which means that if more families make the effort to donate their organic waste, then the country can produce more energy to power their homes and appliances.
The Jerusalem Post reports that Israel has already invested about $250,000 to catalyze a nation-wide recycling initiative, which includes creating awareness of the importance of recycling, building recycling facilities, and providing incentives for all stakeholders to turn trash into treasures.
But this new commitment from the Ministry of Environment sends the strongest signal yet that Israel is serious about not only cutting down waste, but re-using it in constructive ways. Given its constant energy-insecurity, which its new natural gas fields can’t alleviate alone, this is a very smart move.
New factories will house anaerobic digestive facilities that will accelerate the breakdown of organic waste. That process releases methane gas as a byproduct, which can then be harvested and converted to electricity.
We’ve seen biogas used on a small scale and at the Ariel Sharon Park in Israel (formerly the Hiria municipal dump) but this is the first large-scale, government-funded biogas initiative we’ve seen.
The Ministry of Environment has also teamed up with the Ministry of Interior in order to hasten the planning process associated with the country’s Master Plan for Waste Treatment.
Israel has finally declared war on waste. It’s about time!
Plasma gasification plants are modular.
if you want to handle more waste you just add additional modules, maybe someone should tell Elvis Au at the ENB and ask him to remove his blinkers ?
Gasification takes place at temperatures in excess of 4000 degrees C and in the absence of air.
The plasma torches instantly revert the waste materials into molecular form, the resultant hydrogen , carbon and other gases are scrubbed leaving pure hydrogen to power turbines.
The plasma plant emissions are steam and plasmarok.
Plasma gasification is a multi-stage process which starts with feed inputs – ranging from waste to coal to plant matter, and can include hazardous wastes. The first step is to process the feed stock to make it uniform and dry, and have the valuable recyclables sorted out. The second step is gasification, where extreme heat from the plasma torches is applied inside a sealed, air-controlled reactor. During gasification, carbon-based materials break down into gases and the inorganic materials melt into liquid slag which is poured off and cooled. The heat causes hazards and poisons to be completely destroyed. The third stage is gas clean-up and heat recovery, where the gases are scrubbed of impurities to form clean fuel, and heat exchangers recycle the heat back into the system as steam. The final stage is fuel production – the output can range from electricity to a variety of fuels as well as chemicals, hydrogen and polymers.
Plasma is a superheated column of electrically conductive gas. In nature, plasma is found in lightning and on the surface of the sun. Plasma torches burn at temperatures approaching 5500ºC (10,000˚F) and can reliably destroy any materials found on earth – with the exception of nuclear waste.
Waste gasification typically operates at temperatures of 1500˚C (2700˚F), and at those temperatures materials are subject to a process called molecular disassociation, meaning their molecular bonds are broken down and in the process all toxins and organic poisons are destroyed. Plasma torches have been used for many years to destroy chemical weapons and toxic wastes, like printed circuit boards (PCBs) and asbestos, but it is only recently that these processes have been optimized for energy capture and fuel production.
America’s Westinghouse Corporation began building plasma torches with NASA for the Apollo Space Program in the 1960s to test the heat shields for spacecraft at 5500˚C. In the late 1990s, the first pilot-scale plasma gasification projects were built in Japan to convert MSW, sewage sludge, and auto-shredder residue to energy. The Japanese pilot plants have been successful, and commercial-scale projects are under development now in Canada and other countries, by companies such as Alter NRG, from Alberta, Canada.
A base case scenario with a 680 tonne per day (750 US tons) waste gasification plant which would be appropriate for a small city or regional facility, would cost an estimated $150 million (€108 million) to construct. A municipality that funds the entire project through bonds should seek a positive cash flow year-after-year via revenues from tipping fees, recyclables and electricity sales, as well as sales of slag and sulphur. There is considerable range in the values for each of these variables, and any proposed development would require extensive due diligence to determine local prices for each line item. Tipping fees, electricity rates, commodity recyclables, as well as interest rates and taxes, all vary dramatically – creating a model which needs to be thoroughly evaluated for any proposed development.
The economics of waste gasification heavily favour recycling – inorganic materials like metal and glass have no value as fuel and make the gasification process less efficient, even though plasma torches have the ability to melt them. High-value plastics and papers that can be readily separated are far more valuable as recyclables than as fuel. Certain plastics earn €195 per tonne ($300 per US ton) and certain types of paper can earn around €53 per tonne ($75 per US ton). For comparison, a tonne of waste may produce 0.8 MW of electricity, worth around €51 ($70) per MW. It is clear that any of these materials that can be separated and sold, are worth much more as commodities than as fuel.
Liquid fuels are typically produced from syngas through catalytic conversion processes such as Fischer-Tropsch – which has been widely used since World War II to produce motor fuels from coal. Biotech methods to produce liquid fuels are also being developed to use enzymes or micro-organisms to make the conversion.
Much research and effort is being put into developing more selective catalysts and productive enzymes which will raise system efficiencies to levels needed to be competitive. Currently, ethanol from gasification costs more than $2 a gallon (equivalent of €0.37 per litre), and it is estimated that production needs to cost closer to $1.25 (€0.90) or $1.50 (€1.10). Production of ethanol at demonstration scale has shown that one US ton of MSW can produce around 100 gallons (equivalent of 0.9 tonnes producing 380litres) of ethanol, give or take 20%. Cost estimation for ethanol production is difficult, but rough calculations indicate that ethanol could potentially be more profitable than electricity.
Gasification is superior to incineration and offers a dramatic improvement in environmental impact and energy performance. Incinerators are high-temperature burners that use the heat generated from the fire to run a boiler and steam turbine in order to produce electricity. During combustion, complex chemical reactions take place that bind oxygen to molecules and form pollutants, such as nitrous oxides and dioxins. These pollutants pass through the smokestack – unless exhaust scrubbers are put in place to clean the gases.
The objective of gasification systems is to produce a clean gas used for downstream processes which requires specific chemistry, free of acids and particulates – so the scrubbing is an integral component to the system engineering, as opposed to a legal requirement that must be met.
The second argument made against waste gasification is that has the same emissions as incineration. These arguments are based on gasification systems which do not clean the gases and instead combust dirty syngas. Such systems are essentially two-stage burners and are not recommended for environmental reasons. There are many variations of combustion, pyrolysis and gasification – all used in different combinations. Proper engineering is required to achieve positive environmental performance.
As the materials are vapourized the gasses flow out the top, while the molten slag pours out the bottom of the reactor. Gasification of MSW requires temperatures above 1200˚C (2200˚F) and systems are targeted to operate around 1500˚C (2700˚F). As the hot gases exit the reactor they are cooled through a combination of quenching and heat exchangers. The heat is very valuable and is recycled back into the system to generate steam for other purposes.
There are engineering challenges in using heat exchangers at 1500˚C, as temperatures will strain steel and other materials. The heat exchanging sub-system is one of the areas which would benefit from further development.
Electricity is produced using boilers, engines or gas turbines. Gas engines and turbines require very clean gases, but straight combustion to fire a boiler can use less clean gas and has the lowest cost. Steam systems may generate 450–550 kWh per tonne (500–600 kWh per US ton) of MSW. Gas turbines in a combined cycle may generate 900–1200 kWh per tonne (1000–1200 kWh per ton) of MSW. IGCC is considered the state-of-the-art and the most efficient means to generate power from carbon resources. It is the model used for modern clean coal power plants.
Heat recovery steam generators can also use the captured heat from the gases in addition to the heat from the turbine exhaust. The gases pass out of the reactor at around 1200˚C and the heat can be used to generate significant energy for the facility. In theory, the torches and the facility would consume only 25% of the energy produced, leaving 75% available for sale.
This is a guest post by Dawn Santoianni.
Why does diverting waste from a landfill and turning that waste into energy cause so much controversy? Despite the widespread use of waste-to-energy (WTE) in European countries, here in the U.S. WTE has a reputation for being “dirty.” Environmental activist groups frequently oppose WTE because of air emissions concerns. They argue WTE is not “green” and using waste as an energy source discourages reuse and recycling. Despite some successful recycling and curbside composting programs such as in Portland, Americans currently only recycle or compost 34 percent of municipal waste generated, according to the Environmental Protection Agency. The U.S. has relatively low landfilling costs which enable our wasteful ways. By comparison, in Germany the majority of waste is recycled, composted, or processed by biological and thermal methods. The success of recycling and WTE in Germany and other European countries arose because of government mandates and disposal costs that reflect the scarcity of landfill space. Globally, 70 percent of municipal solid waste is landfilled, with projections that the volume of MSW will doublewithin the next 15 years.
Using municipal solid waste (MSW) to generate energy can reduce the amount of material sent to landfills by 90 percent, avoiding greenhouse gas emissions from landfills – the third largest human-related source of methane emissions. Studies estimate the amount of energy in U.S. food waste alone is equivalent to 350 million barrels of oil, or enough to power 16.2 million households each year. Beyond MSW, the U.S. has issues managing animal wastes, construction and demolition debris, and sewage sludge to name a few. America needs a transformation on how we view waste and WTE. Innovative technologies are promising to help us start to see the resource in what we currently waste and demonstrate that WTE can be clean.
Waste-to-energy in the U.S. is still widely perceived as either energy derived from landfill gas or incineration. Waste-to-energy is not a single technology, but a variety of technologies – both thermal and biological – that can be used to convert waste products into electricity or fuels. While landfill gas is better used than emitted as greenhouse gas, activists want to divert waste from landfills, not produce more gas. Incineration of MSW typically employs a mass burn method and requires pollution controls including those for mercury, lead, dioxins/furans, particulate matter, nitrogen oxides and sulfur dioxide. Mass burn facilities require little or no preprocessing of waste – simultaneously an attractive economic feature and a root cause of the image problem. Prior to improved waste sorting and recycling efforts in recent years, incinerators would burn a heterogeneous mixture that included metal wastes, producing considerable air emissions. Mass burn facilities are often permitted as “major sources” of hazardous air pollutants by the EPA. Of the 87 operating WTE plants in the U.S., 63 are mass burn. In New York, efforts to generate energy from city trash have met with sharp criticism and protests, even though direct combustion methods were specifically excluded from consideration. Therein lies the problem: waste-to-energy has such a negative connotation that cleaner technologies are also being overlooked.
A thermal technology that eliminates many of the objections to WTE is gasification. Gasification is a fundamentally different thermal process than incineration. Waste (MSW or other) is pre-processed using a combination of screening, size reduction, and separation to remove inorganic materials such as metal and glass. The resulting waste is compressed and dried into pellets or bricks, which is used as feedstock to the gasifier. Unlike incineration where the waste is burned, gasification uses high temperatures and pressures in a substoichiometric atmosphere (less oxygen than required for complete combustion) to convert the waste into a syngas that is comprised primarily of carbon monoxide and hydrogen. The syngas can be subsequently used to produce electricity in a steam process or gas turbine, or to power an internal combustion engine. Residual ash is disposed or further processed for material recovery. The low oxygen environment prevents the formation of dioxins, furans, or large quantities of nitrogen oxides (NOx) and sulfur oxides (SOx). Due to the low volume of process gas, gasification requires less expensive emissions control equipment. How the syngas is used will dictate the extent of gas conditioning required. Dioxin and furan reformation in the syngas can be prevented by the low oxygen atmosphere, absence of metal particulates, and quenching (rapid cooling). Recent studies have shown that gasification of MSW could have substantial environmental benefits, saving 0.3 to 0.6 tons of carbon equivalent emissions per ton compared with landfill disposal.
Two other thermal technologies are plasma arc gasification and pyrolysis. Plasma gasification uses an arc of ionized gas to heat the feedstock to extremely high temperatures, breaking it down into elemental byproducts. The residual inorganic material is vitrified – turned into a glass-like substance, which is inert (non-leaching) and exceeds EPA standards. However, plasma gasification remains an expensive technology because of the energy required for the plasma arc torch. A demonstration project in Florida has received a final permit and will process 600 tons of waste per day. Notably, the facility’s permit limits for the six EPA criteria pollutants are the lowest in the country for the size of the facility. Another project is Texas is still in the early planning stage. In pyrolysis, the feedstock is thermally decomposed at moderate to high temperatures in the absence of air, resulting in liquid or gaseous fuel and a solid residue called char. If pyrolytic fuels are combusted to produce electricity, emission control equipment is required. Pyrolysis and gasification are sometimes confused, even though the operating conditions and products differ. Gasification, plasma gasification, and pyrolysis offer improved waste conversion efficiencies (25 to 50 % higher) compared with conventional mass burn incineration.
Unfortunately, confusion over technology has led many to oppose new WTE gasification projects as incinerators in disguise, or “too good to be true.” Adding to the confusion is the lack of substantive emissions data from gasification facilities in the U.S. Studies of biomass gasification (not just MSW, but woody biomass as well) show a wide range of emissions due to the variability in feedstock, pretreatment, operating conditions, and configuration. As a result, when community groups investigate thermal technologies for MSW, emissions and operational data from sources that are dissimilar from the proposed project are misinterpreted. Public opposition combined with unfavorable economics (low landfill prices, required preconditioning of waste) have hampered the commercialization of gasification, plasma arc gasification, and pyrolysis.
While gasification is still struggling to overcome the incinerator reputation for MSW, the technology has had demonstrated success with animal waste. The Denver Zoo’s Elephant Passage exhibit achieved platinum LEED certificationusing an innovative gasification system that converts both human trash and animal waste into renewable electricity to power the exhibit. Successful gasification projects such as this may pave the way for more sustainable animal waste management. Typically, animal manure is stored on-farm or spread on fields as a nitrogen and phosphorus-rich soil enhancer. However, animal manure can be too much of a good thing. The concentration and size of animal production operations cause waste to be stored in large stockpiles (as in the case of poultry litter), lagoons (hog and dairy cow waste), or applied to over-fertilized agricultural lands. These practices can cause runoff that leads to surface water contamination. Waste-to-energy technologies can improve animal waste management by providing numerous benefits, including water quality improvement and odor reduction. Notable animal waste gasification projects include a pilot-scale Georgia gasification plant which converted Tyson poultry litter to process steam, and an Iowa poultry farm demonstration project that has recently secured funding.
Biological technologies – ready for commercial scale?
Non-thermal technologies use biological processes to break down waste. Anaerobic digestion, a process that employs bacterial decomposition in an oxygen-starved atmosphere, is becoming a preferred method for high-water-content animal manures as well as other waste streams. Anaerobic digestion is the same process that causes methane emissions from uncovered waste lagoons, but modern technology utilizes enclosed vessels to capture odors, maintain and optimize digestion conditions, and collect the nutrient-rich residue left behind. The biogas produced from anaerobic digestion is 55 to 70 percent methane, and can be used to produce electricity or refined as a biofuel. Several dairy farms across the U.S. are now utilizing biodigesters to generate energy. The barrier to large-scale penetration has been unfavorable economics and material handling limitations. Anaerobic digestion systems cannot process mixed waste and are sensitive to the moisture content of the waste. As a result, large quantities of water may be required. Innovations have overcome the latter problem as the first commercial-scale high-solids anaerobic digestion systemprocessing food waste from regional producers recently made its debut in California.
If anaerobic digestion suffers from an image problem, it is that commercial scale is difficult to achieve because of the time it takes to process waste and the preconditioning required. While an incinerator can process over 500 tons MSW per day, the first commercial-scale digester in California plans to process 100 tons per day by 2013. Most digesters fall into the 10 to 50 tons-per-day range. EPA is attempting to encourage WTE from anaerobic digestion with aninteractive tool to match biogas producers with users, including biogas produced at wastewater treatment plants.
Exciting new technology developments utilize algae and fungi which thrive at higher temperatures to process waste into biofuels. Utilizing waste for biofuel development is preferable to using starchy food-based biomass, such as corn for ethanol. Cellulostic-derived ethanol has been produced only in laboratories and small demonstration scales due to the high cost of production, despite government mandates requiring its use. The enzymes to break down cellulosic biomass have been the main economic hurdle, accounting for half the cost of cellulosic ethanol production. Researchers at the Department of Energy are cataloging fungi that can break down cellulosic waste biomass into simple sugars for fermentation into ethanol. Large collections of fungi can be explored to identify those that produce cost-effective enzymes for the breakdown of wastes and development of biofuels.
Lessons learned from the biodiesel market is that once waste becomes a commodity, feedstock availability and price increases can become issues, according the North Carolina Biofuels Center. As biodiesel gained in popularity withproduction surpassing one billion gallons in 2011, shortages of waste oil have actually induced thefts of used cooking oil. Limitations on the amount of feedstock waste, called yellow grease (as well as soybean oil) ultimately limit the volume of biofuels that can be developed. For MSW and animal wastes, supply chain management including the availability, location, volume, and control of a waste stream will make or break the economic viability of a WTE plant. Issues with waste availability can lead to the use of supplemental feedstock or reduction in material recovery efforts and is one of the main objections to new MSW WTE plants.
So do new technologies bring us closer to zero waste or sabotage our recycling efforts? If we start to look at waste as an energy resource, will that only encourage wastefulness? Data suggests that the recycling rate in communities with WTE facilities are higher than the national average, and that landfill diversion rates may be higher for WTE communities than for communities attempting zero waste. Some municipalities are successful in diverting waste from landfills by focusing on reducing and recycling first, followed by WTE. Waste-to-energy still remains less attractive than trucking to landfills because of high capital costs and the production cost for electricity. Policy at the federal, state, and municipal level can shift those economics by imposing fees to make landfilling more expensive, instituting curbside programs that make it easier for households to recycle and compost, and encouraging WTE as part of an integrated waste management solution.
About the Author: Dawn Santoianni is a combustion engineer who has worked on energy and environmental issues for 20 years. She has conducted air pollution research as a contractor for the U.S. Environmental Protection Agency and testified before a Congressional subcommittee on a proposed environmental regulation. Dawn currently works as technical writing consultant through her company, Tau Technical Communications LLC. When she is not debating or blogging about energy policy, Dawn spends time at her “cool” job – volunteering at an educational wildlife facility where she helps care for lions, tigers and wolves. She enjoys reading about particle physics and is intrigued by the experiments at the Large Hadron Collider. Follow on Twitter @tautechnical. Dawn was invited to guest post by Plugged In‘s Melissa C. Lott.
Plugged In Next: Plenty of Fish in the Sea?
WTE seems to drag “Rube Goldberg” baggage everywhere it goes. There has never been a shortage of whimsical engineering and fly-by-night companies, but then again humans have been trying since antiquity to turn lead into gold.
I’ve never understood the obsession with complex systems that upgrade crude wastes into pipeline-grade gas and automotive fuels rather than simply producing heat/electricity, especially when the people next door use virgin natural gas and automotive fuels to produce heat/electricity.
The reason so many environmental/energy efforts have failed to be economical or popular is because they are trying to ride against the tide of entropy. Energy must be viewed not only in quantity but also quality, with high-grade energy being reserved for high-grade use and the low-grade wastes being used to meet low-grade needs (like space heating).
What’s wrong with just biomass gasification at home. Small biomass gas stoves are all over the internet and You-tube. I for one heat my coffee and tea with junk mail, and the resulting ash is way smaller than the waste paper that would have ended up in the land fill.
The stoves are easy to make and practically free. Why pay for energy when you are throwing it away. Here is free energy that is really free and doesn’t require zero point energy, positrons or neutrinos. It just needs the personal imagination to do it.
joenn – I obviously haven’t looked at all the biomass stoves available online, but the ones I have seen that bill themselves as “gasifiers” are direct combustion stoves. Depending on what you burn, you could have some unhealthy emissions. Even modern gasification plants employ syngas cleaning equipment.
RankineCycle – I don’t agree with characterization that WTE has Rube Goldberg complexity. If you don’t care about emissions or environmental impacts, then you could simplify the process. Energy from waste needs to be used locally – I don’t think there is any misconception about piping biogas/waste biofuels long distances.
It is expected to divert up to 350,000 tonnes of non-recyclable waste from landfill per year – helping to meet the UK’s waste diversion targets.
The facility’s developer claimed that the technology offers a more efficient, cleaner conversion of waste to energy than traditional technologies and has the potential to generate a wider range of useful products, including heat, hydrogen, chemicals and fuels.
Air Products said that emissions are reduced due to the high temperature used in the process while the waste is converted into a syngas and a by-product, a non-organic vitrified slag which can be recycled, for use in road bedding and other construction based applications.
“Air Products’ announcement reflects the UK’s commitment and support for clean energy, combined with our stable and transparent environment for investors,” he added.
“Transparency, longevity and certainty underpin the UK’s commitment to renewable energy. The renewable obligations banding review demonstrates the value the UK Government places on energy security and consumer protection against fluctuating fossil fuel prices, as well as job creation and business growth,” concluded Clegg.
Following last week’s response by DECC to the consultation on the Renewables Obligation Banding Review – which sets out support levels for renewable energy technologies for the period 2013 to 2017 – there has been further reaction of the waste industry.
LEHIGH VALLEY, Pa., Aug. 7, 2012 /PRNewswire/ — Air Products (NYSE: APD) today announced it will build and operate the world’s largest renewable energy plant in the UK using advanced gasification energy-from-waste (EfW) technology. The Tees Valley plant, located at the New Energy and Technology Business Park, near Billingham, Teesside, will be the first of its kind in the UK, and the largest of its kind anywhere in the world with an approximate capacity of 50MW.
The Tees Valley Renewable Energy facility’s core conversion technology, a Westinghouse gasifier supplied by AlterNRG, has been used successfully in other countries such as Japan. This is the largest energy-from-waste facility based on this technology globally and the first time that it will be used in the UK at this scale. It provides the foundation for a renewable energy source using waste which could otherwise go to landfill. Advanced gasification is a more efficient energy-from-waste process than incineration and has a lower environmental impact, producing 42% less CO2 emissions per MWh than incineration. An advanced gasification-based plant can produce a number of different outputs from waste, including electricity, heat, chemicals, fuels, or renewable hydrogen that could be used to power low-carbon vehicles.
NOTE: This release may contain forward-looking statements within the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are based on management’s reasonable expectations and assumptions as of the date of this release regarding important risk factors. Actual performance and financial results may differ materially from projections and estimates expressed in the forward-looking statements because of many factors not anticipated by management, including, without limitation, unanticipated contract terminations or cancellation or postponement of the projects; interruption in ordinary sources of supply of raw materials, including waste; the ability to attract, hire and retain skilled workers; the impact of environmental, healthcare, tax or other legislation and regulations; efficacy or safety concerns with respect to the Company’s technology or operations; the inability to obtain necessary regulatory approvals; difficulty or excessive cost of construction of the facility and/or the infringement of patents or intellectual property rights of others and other risk factors described in the Company’s Form 10K for its fiscal year ended September 30, 2011. The Company disclaims any obligation or undertaking to disseminate any updates or revisions to any forward-looking statements contained in this document to reflect any change in the Company’s assumptions, beliefs or expectations or any change in events, conditions, or circumstances upon which any such forward-looking statements are based.

References: §7429
 v. 
 §27
 §172
 §166
 §163
 §97