March 2012 - Power Air Quality Insights 46

Mercury Measurement and Control is Hot Topic Hour on Thursday, March 15, 2012

NOTE: Because of the strong interest in mercury control, we have planned two sessions to discuss this subject – the first on March 15^th and the second on April 12, 2012. Any person that attends the March 15^th Hot Topic Hour will automatically be registered for the session on April 12^th.

The Utility MACT or MATS and the Industrial Boiler MACT have limits for mercury emissions from coal- and oil-fired boilers that are very low. So low, that it is questionable whether or not the required reductions can be achieved in all cases given the constraints imposed by reducing other pollutants simultaneously. Many also believe that it may be very difficult to measure mercury reliably and accurately to determine and prove what removal efficiency is actually being achieved.

Control of mercury emissions from coal-fired boilers is currently achieved via three general broad methods: use of coals with low mercury content along with coal prep or washing, activated carbon injection (ACI), and various multi-pollutant control technologies in which Hg capture is enhanced in existing control devices for SO₂, NO_x, and particulates. Multi-pollutant methods include capture of Hg_p in PM control equipment and soluble oxidized Hg compounds in wet FGD systems. SCR NO_xcontrol systems are also used to enhance oxidation of elemental Hg⁰ in flue gas to increase the mercury removal in a wet FGD.

The overall scheme of regulations will make it even more difficult to develop a strategy and select the most appropriate method for mercury control. An integrated approach that considers how to capture mercury as well as other pollutants and dispose of them in an environmentally friendly manner will be necessary.

The speakers listed below will help us understand the current situation relative to the monitoring and control of mercury from coal-fired power plants. They will address the impact of the MATS on power plant operators; the key issues to be considered when developing a strategy to achieve compliance with the MATS; the current status of and new developments relative to the injection of activated carbon and other materials for mercury removal; the multi-emission control technologies available and under development with their applicability, capabilities, and limitations and present other alternatives available to achieve compliance with the expected regulations.

Jim Wright, Director of Source Testing Mercury at Clean Air Engineering, Inc., will discuss mercury measurement, specifically continuous monitoring at very low levels using sorbent trap technology. He will describe the advantages and disadvantages of this approach and present real-world data from the utility industry that has been collected over the last five years.

Marc Sylvester, Vice-president for Sales at Midwest Energy Emissions Corp (ME2C), will discuss control of mercury emissions from major utility and industrial boilers utilizing patented technologies. ME2C has worked closely with the Energy & Environmental Research Center (EERC) of the University of North Dakota to develop and deploy the best performing and most cost effective mercury control technologies in the world. ME2C will discuss its Sorbent Enhancement Additives technology and its most recent commercial installation. This program is designed to achieve greater than 90 percent capture at less than half the cost of Brominated Activated Carbon.

John Darrow, Associate and Jeff Kolde of the Mercury Control Technology Team at W.L. Gore & Associates, Inc. will describe a new fixed-bed sorbent technology for controlling mercury emissions from combustion applications. This “end-of-pipe” solution provides a simple and effective way to continuously capture both elemental and oxidized mercury from flue gas streams for typically several years at a time without requiring regeneration. Drawbacks of activated carbon injection such as flyash contamination and interference by SO₃ are completely avoided. In addition to very high mercury removal efficiency, SO_x emissions are reduced as a co-benefit.

Bobby IT. Chen, Client Program Manager of Integrated Emissions Solutions at Shaw Environmental & Infrastructure Group, will present some very up-to-date information on the control of mercury from plants burning lignite coal.

Sharon M. Sjostrom, P.E., Chief Technology Officer at ADA Environmental Solutions (ADA-ES)

Dr. Ron Landreth, Manager of Customer Technical Services Environmental Division of Albemarle Sorbent Technologies Corporation

Bobby IT. Chen, Client Program Manager of Integrated Emissions Solutions at Shaw Environmental & Infrastructure Group

We cannot afford to wait for so-called “Clean Coal.” We need a strategy which moves us forward to cleaner coal now. We should immediately start building ultra-supercritical, highly efficient, low polluting coal-fired power plants to replace the oldest and least efficient existing power plants. This is the key first step toward progressive and opportunistic cleaner energy.

There are too many uncertain variables for the U.S. and the world to set rigid strategies and time tables. The course recommended in the McIlvaine publication, Fossil & Nuclear Power Generation: World Analysis & Forecast is labeled “Progressive and Opportunistic Cleaner Energy.”

Sometime within the next 100 years, the fossil fuels will be depleted, while solar and other renewable technologies will be advanced to the point at which they can supply the world’s electricity. Long before fossil fuels are depleted, there will be a priority to convert them to liquid fuels. Even now it is less expensive to make gasoline from U.S. coals than to import oil at $100/barrel and refine it. If shale gas is plentiful, it would also make sense to convert it to gasoline rather than use it in power generation.

“Clean Coal” has been viewed narrowly as incorporating carbon capture and sequestration. However, there are several other equally important factors. One is conversion efficiency. It is possible to greatly reduce CO₂ emissions per unit of electricity produced by use of advanced ultra-supercritical technology. Another is emission control. Coal-fired units can be fitted with pollution control equipment to remove 99 percent of the pollutants (particulate, acid gases, toxic metals and NO_x).

A third factor contributing to cleaner coal is resource synergy. The large steam plume from the coal-fired power plant cooling tower is testimony to the wasted heat which could be better used to operate fish farms, grain driers, ethanol plants and any operation needing low pressure steam.

Another resource synergy has to do with fuels. If cellulosic ethanol becomes commercialized, there will be large quantities of waste biomass which can substitute for a portion of the coal. Sewage sludge and garbage can be gasified and used as “reburn” fuels in coal-fired boilers. High chlorine coals present the opportunity to make 30 percent hydrochloric acid and eliminate the pollution associated with alternative production methods.

The conclusion is that the cleanliness of coal is defined holistically to be the net emissions taking into account carbon capture, efficiency, emission capture and resource synergy. Carbon capture can be a follow on investment. Initially the focus should be on efficiency, emission capture and resource synergy.

Carbon capture and sequestration will only make sense when utilized on highly efficient boilers. Why not build the ultra-supercritical, ultra low emission units now, and then equip them with carbon capture at a later date? Ironically, the Chinese and the Indians are already on this track, while the U.S. is only doing the research.

Due to anomalies in the legal system, environmental advocates have become their own worst enemy. By resisting the construction of any new plant, they will cause 285 GW of old coal-fired power plants to still be operating in 2035. This is the conclusion of the new EIA forecast.

Fuel	Capacity GW in 2035
Coal	285
Gas	408
Nuclear	112
Renewables	168
Other	27
Total	1,000

If these power plants were replaced by ultra-supercriticals, they would use 20 to 30 percent less coal and generate 20-30 percent less CO₂ while emitting only 10 percent of the pollutants emitted by the old power plants.

Cost is a dominant factor in the opportunistic progressive strategy. The replacement of old coal-fired power plants with new ultra-supercriticals will be extremely cost effective. They are using 20-30 percent less coal and are 20 to 30 percent smaller than the power plants they replace. With modern control systems, they are easier to operate and maintain. As a result, the replacement can be justified with just a 25 year expected life for the new ultra-supercritical.

At the end of the 25 years, carbon capture and sequestration can be added or the plant replaced with wind or solar generators. In any case, the reduction in emissions for the next 25 years will be achieved at virtually no cost.

An ultra–supercritical coal-fired power plant burning 20 percent biomass, providing steam for synergistic industrial uses and equipped with 90 percent carbon capture, would actually be a net carbon reducer, so this would be the cleanest energy. The best solar and wind would at best be carbon neutral.

Worldwide sales of scrubbers, absorbers, adsorbers and biofilters will grow at a 7 percent CAGR over the next five years due largely to new technologies and applications as opposed to new regulations impacting existing applications. This is the latest finding in Scrubber/Adsorber/Biofilter World Markets published by the McIlvaine Company. (www.mcilvainecompany.com)

In 2012, 14 percent of the market will be in a miscellaneous “other industries category.” However, over the next five years this is the category which will see the biggest growth. In 2015, large vessels will either have to install scrubbers or greatly reduce the sulfur in the fuel they burn. The economics dictate the scrubber option. Scrubbers for vessels will be a big enough market to rank higher than pulp and paper, food, and electronics.

Another new application is the cement industry. New air toxic regulations in the U.S. will require retrofitting scrubbers on many plants. Some plants in Europe and Asia will install scrubbers.

New technologies will also boost scrubber revenues at the expense of some other types of equipment. Market share will be taken away from the selective catalytic reduction systems used for NO_x control as scrubbers using ozone capture some of the market. Ozone converts NO_x to a soluble NO₂ which can be captured in scrubbers. Ozone will also be increasingly used in combination with scrubbers to compete with carbon adsorbers and biofilters for odor removal from municipal wastewater and food plant stacks.

In the 1960 to 2000 period, the scrubber market was largely driven by the regulations in Europe and the U.S. which required existing plants to install equipment. This program has been completed. But now there is a large investment in new plants in Asia. This includes waste-to-energy plants, steel mills, chemical plants and municipal wastewater treatment plants, so the market in Asia is already larger than other regions and will continue to grow at a faster pace.

Better storage technology would allow for the greater adoption of renewable energy. Many are working on developing better means to store electricity. McIlvaine Renewable Energy Projects and Updates track these developments.

MHI Delivers Large Capacity Energy Storage System Using Lithium-ion Rechargeable Batteries

Mitsubishi Heavy Industries Ltd (MHI) has delivered a large-capacity energy storage system employing lithium-ion rechargeable batteries to the Shimizu Institute of Technology in Tokyo. The institute, a technology arm of Shimizu Corporation, a major Japanese construction firm, is presently conducting advanced studies, including verification testing, into various technological areas, including microgrids, which are a localized power management system, and smart BEMS (building and energy management system). The energy storage system, which is capable of 100 kilowatt (kW) output and storage of 60 kilowatt hours (kWh), is one of today's largest indoor lithium-ion battery-based systems in Japan. Going forward MHI and Shimizu will jointly conduct tests using the energy storage system and verification of the microgrid system, in a quest to respond to increasing social needs for stationary energy storage systems.

The microgrid installed at the Shimizu Institute of Technology has a total output of 600 kW. It consists of multiple power sources, including a photovoltaic generation system, and an energy storage system, all configured for integrated control.

The lithium-ion rechargeable battery energy storage system installed in the microgrid system uses 320 units of a 50 Ah (ampere hour) class cell. Compared with storage systems using other battery types, such as lead-acid and nickel-hydride batteries, the system adopting lithium-ion battery, which has two to three times higher energy density, offers greater compactness plus the capability to supply higher power output in a short time. The energy storage system consists of batteries and their racks, a direct current/alternating current (DC/AC) convertor, and a system control device.

MHI has been marketing the lithium-ion rechargeable battery energy storage system for multi-unit apartment buildings. The company has also completed the development of Japan's first container-type megawatt-class energy storage system, using more than 2,000 units of lithium-ion cell. The company has already begun marketing the system for a variety of applications: as a peak-cut system to accommodate peak electric demand, as an auxiliary power source to achieve stable power supply in unstable power grid areas, and as a power grid stabilization system to promote renewable energy such as wind power and solar energy.

The California Energy Commission awarded $227,000 to the Sacramento Municipal Utility District (SMUD) for a research project demonstrating how energy storage can be integrated into local microgrids.

Funding for the project will come from the Commission’s Public Interest Energy Research (PIER) program. The award is the result of a solicitation where PIER matched American Recovery and Reinvestment Act (ARRA) funds with the goal to bring as much ARRA dollars into California as possible.

SMUD will demonstrate a one-megawatt advanced zinc bromine flow battery energy storage system for utility grid applications and validate the potential penetration of the system. The project will demonstrate the benefits of the storage system for load shifting, peak shaving (sending power back to the grid when demand is high), support for microgrid operations, and renewable energy integration.

SMUD plans to set up two demonstration sites using Premium Power Corporation’s energy storage system. One system will be at SMUD’s Sacramento headquarters; the second will serve the Anatolia III SolarSmart Homes community in Rancho Cordova.

The SMUD headquarters system will help improve microgrid operations, emergency operations, and boost peak period campus operation using electricity generated during off-peak hours. The system at SMUD’s substation will be integrated with the Anatolia III SolarSmart Homes community, which will have 600 homes totaling 1.2 MW of photovoltaic generating capacity installed by the time the system is activated. A common control system at SMUD headquarters will control both storage systems to demonstrate fleet control of multiple distributed storage devices.

The total cost of the SMUD project is $5.15 million. The commission’s funding will supplement a $2.46 million ARRA award that SMUD, along with project partner Premium Power Corporation, received from the U.S. Department of Energy. SMUD is providing $2.46 million for the project.

ABB, 4R Energy, Nissan North America, Inc. (NNA) and Sumitomo Corporation of America have formed a partnership to evaluate the reuse of lithium-ion battery packs that power the Nissan LEAF, the world’s first and only all-electric car designed for the mass market.

The purpose is to evaluate and test the residential and commercial applications of energy storage systems or back-up power sources using lithium-ion battery packs reclaimed from electric vehicles after use. Energy storage systems can store power from the grid during times of low usage and feed that electricity back into the grid during periods of peak demand, increasing grid performance and providing back-up power during outages. The team plans to develop a LEAF battery storage prototype with a capacity of at least 50 kilowatt hours (kWh), enough to supply 15 average homes with electricity for two hours.

Electric vehicle batteries have longer lives than those of personal computers or cell phones, with up to 70 percent capacity remaining after 10 years of use in an automotive application. This longevity allows them to be used beyond the lifetime of the vehicle for applications such as a smart-grid community energy management system or battery energy storage.