All of the Above Energy, Part 2

The February 4 post looked  at the combustion technology to have been used at the now-terminated Las Brisas power plant in Corpus christi, TX, and provided some examples of clean tech patents in the realm of carbon trading and offsets, carbon sequestration, and carbon emissions reduction that might have been applied at Las Brisas. In this post, we continue with a summary of recent inventions in the fields of toxic emissions reduction and reducing fine particulate matter emissions from power plants.

Toxic Emissions Reduction

One of the substances potentially to be emitted from the Las Brisas plant was mercury. US Patent 7,862,725, “Method for mercury capture from fluid streams,” was granted to David Mazyck and co-inventors in January 2011. The patent was assigned to the University of Florida Research Foundation Incorporated. It provides a “method for removing mercury from a fluid stream includes the steps of providing a porous composite material comprising a substrate and a plurality of catalyst and/or photocatalyst particles, and contacting substrate with a fluid stream. The porous composite material adsorbs and/or then oxidizes or reduces metallic species including elemental mercury. A fossil fuel fired power plant can include an emission control device comprising the porous composite material to filter flue gas to and thereby minimize mercury emissions into the environment.”

Reducing Fine Particulates

USEPA regulations limit the amount of fine particulate matter than can be emitted from stationary sources including power plants. In 1997 EPA revised the National Ambient Air Quality Standards (NAAQS) to drop the particulate diameter to be controlled from 10 microns to 2.5 microns (PM2.5). In 2006 the allowable concentration that could be released was cut almost in half from 65 to 35 micrograms per cubic meter. For reference, a strand of human hair is on average about 100 microns, thus the particulate matter regulations target an object 40 times smaller than the diameter of human hair. At a concentration of 35 micrograms per cubic meter, it would take 1,295,978,200 cubic meters to obtain one pound of PM2.5. This is equivalent to the volume enclosed by NASA’s Vehicle Assembly Building at the Kennedy Space Center. Times 354.

Particulate matter is generally removed from power plant flue gas by either electrostatic precipitators (ESPs) and/or fabric filters (‘baghouses’). Most ESPs are dry, but in some settings wet ESPs are needed. ESPs use high-voltage fields to apply electric charges to the particles moving through the field. The charged particles then move toward a collection surface of opposite charge, where they accumulate and are then collected for disposal. ESPs were originally used in the early 1900s.

US Patent 7,776,141 was granted to Song Wu and co-inventors in August 2010. “Methods and apparatus for performing flue gas pollution control and/or energy recovery,” assigned to Hitachi Power Systems America, Ltd., provides methods and apparatus for pollution control for use in a coal power plant. “Ash is collected and injected into the flue gas stream at a location upstream of a cooling module. The ash acts as an absorbent and/or reactant material onto which condensate may condense. By re-introducing ash to keep the condensation forming wet areas within the system, lower cost materials which are less corrosion resistant than needed for wet operating conditions can be used. Mercury recovery and SO3 removal is facilitated by the cooling process and re-introduction of collected ash. Activated carbon and/or an alkali absorbent material may be added. Use of a dry ESP and/or fabric filter as opposed to a wet ESP for particulate collection leads to cost benefits. Energy recovered by the cooling of the flue gas may be re-used to heat turbine condensate leading to improved energy efficiency.” Thus this invention not only reduces particulate matter but also sulfur and mercury emissions.

A Promise Kept

In November 2008, candidate Obama in an interview with the San Francisco Chronicle said:

"The only thing I’ve said with respect to coal, I haven’t been some coal booster. What I have said is that for us to take coal off the table as a (sic) ideological matter as opposed to saying if technology allows us to use coal in a clean way, we should pursue it."

So if somebody wants to build a coal-powered plant, they can.

It’s just that it will bankrupt them.

Clean Tech for Fossil Fuel Power Plants?

There is a tremendous amount. The equipment and methods to be derived from the patents listed here and in part 1 may or may not have been applicable to Las Brisas – that would require detailed engineering evaluations performed during plant design. However, technological innovations are available to apply at all power plants in the US. In many cases, top-down regulatory strictures make installing them cost prohibitive. In other cases, the change in the past few years regarding fuel costs (e.g., dramatically lower natural gas prices) lead plant owners to decide upon plant retirement or, sometimes, reconstruction to allow use of an entirely different fuel. One would think that for all the talk of using innovation, clean tech, protecting American jobs, and taking an ‘all of the above’ approach, we might see fewer instances of plants like Las Brisas being forced into oblivion.

Footnote

The Daily Caller reports that,

"The energy company Duke Energy, which has close ties to President Barack Obama’s administration and is involved with the pro-Obama political operation Organizing for Action, completed two new expansive wind power projects this month in the same region near Corpus Cristi, Texas where a major job-creating coal power project was recently disbanded."

Duke Energy announced the completion of the Los Vientos I and Los Vientos II wind projects on January 14.

The Los Vientos projects are located “approximately 120 miles south of Corpus Christi and 20 miles inland from the Gulf of Mexico,” according to a 2011 Duke press release.

The largest-ever Duke wind construction projects, they add 402 MW of intermittent power to the grid, less than one-third of Las Brisas’ baseload generation capacity.

All of the Above Energy, except for …

Source: http://www.lasbrisasenergy.com/technology.html

Chase Power Development, LLC of Houston, TX has announced that it is ceasing operations. The company was attempting to permit and build the Las Brisas power plant in Corpus Christi, TX. Las Brisas, anticipated to cost $3 billion and create 1,300 direct and 2,600 indirect jobs, was a planned 1,320 megawatt plant with circulating fluidized bed boilers that would use petroleum coke as its primary fuel source. The petroleum coke was to be obtained from three local refineries. Chase Power CEO Dave Freysinger was quoted in the Corpus Christi Caller as saying that the project succumbed to overwhelming USEPA regulations on carbon-based fuel permitting requirements and emission standards for petroleum coke. Opponents of the plant claimed it would emit toxic chemicals and fine particles into the air.

The Technology

Las Brisas was to have incorporated circulating fluidized bed combustion technology, widely used in the electricity generation industry. The following description from the Las Brisas Energy Center web page explains the process depicted in the accompanying flow diagram:

Fuel Input

Fuel and limestone are fed into the combustion chamber of the boiler while air (primary and secondary) is blown in to “fluidize” the mixture. The fluidized mixture burns at a relatively low temperature and produces heat. The limestone absorbs sulfur dioxide (SO2), and the low-burning temperature limits the formation of nitrogen oxide (NOX) – two gases associated with the combustion of solid fuels.

CFB Boiler

Heat from the combustion process boils the water in the water tubes turning it into high-energy steam. Ammonia is injected into the boiler outlet to further reduce (NOX) emissions.

Cyclone Collector

The cyclone is used to return ash and unburned fuel to the combustion chamber for re-burning, making the process more efficient.

State-of-the-Art Air Quality Control System

After combustion, lime is injected into the “polishing scrubber” to capture more of the (SO2). A “baghouse” (particulate control device) collects dust particles (particulate matter) that escape during the combustion process. Activated Carbon Injection (ACI) will be installed upstream of the fabric filter to enhance the removal of mercury and HAP’s [i.e., Hazardous Air Pollutants].

Steam Turbine

The high-pressure steam spins the turbine connected to the generator, which converts mechanical energy into electricity.

Transmission Lines

The electricity produced from the steam turbine/generator is routed through substations along transmission lines and delivered to distribution systems for customer use.

All of the Above Energy?

The White House website links to a document titled “Obama Administration Record on an All-of-the-Above Energy Strategy.” The document states:

The President is committed to an all-of-the-above strategy that expands production of American energy resources, like oil and natural gas; increases energy efficiency to save families and businesses money at the pump; and develops cleaner, alternative fuels to reduce our oil dependence.

The document also says that the US “need[s] to take control of our own energy future by out-innovating and outbuilding our global competitors.”

What are some recent innovations that might have applied to the now-defunct Las Brisas plant, which it would seem, due to its underlying oil-based fuel, might have been part of the all of the above energy strategy?

Petroleum Coke

Petroleum coke, according to the US Energy Information Administration, is a coal-like material produced as part of the petroleum distillation process. “Petroleum coke has uses in the electric power and industrial sectors, as fuel inputs or a manufacturing raw material used to produce electrodes for the steel and aluminum industries. In 2011, the refining industry supplied 132 million barrels of petroleum coke with most of it subsequently consumed as fuel.”

US Patent 7,901,473, “Pre-burning, dry process methodology and systems for enhancing solid fuel properties,” was granted to CoalTek, Inc. (Tucker, GA) in March 2011. Inventors Jerry Weinberg and colleagues developed “a dry electromagnetic process technology … that can be controlled and monitored to selectively alter and enhance solid fuel properties for the application in question. Specific changes include altering the mechanical structure and chemical composition of solid fuels such as coal, coal coke or petroleum coke, increasing the BTU/lb to optimum levels, decreasing all forms of sulfur, and decreasing ash, while maintaining the BTU/lb of the fuels. A new family of solid fuel designer coals not found in nature can be produced via these methods and apparatus.”

Their invention not only increases the heat content (Btu/lb) of the fuel, but also decreases sulfur (and hence, sulfur dioxide emissions) and ash (reducing the amounts of fly and bottom ash that must be removed from the flue gas or boilers and subsequently disposed of, and the amounts of fine particulate matter produced. More on this in a future post.)

Carbon Emissions Trading & Offsets, Sequestration, and Reduction

This is an active area of innovation and patenting. In the last five years the following inventions (and there are many more in this area) have been approved by the US Patent Office.

Carbon Trading & Offsets

Bank of America makes it easy for commercial entities to do their part to help stop global warming. US Patent 8,214,258, “Systems, methods and computer program products for a comprehensive environmental benefit program associated with a commercial credit card,” issued in July 2012 to Jeffrey Pauly and David Vogel. “Systems, methods, and computer program products are provided for a comprehensive environmental benefit program associated with purchases made by a corporate entity and, more specifically, purchases associated with a commercial credit card. According to embodiments herein disclosed, environmental impact data, such as ecological or carbon footprint data may be determined based on the purchases made by a commercial entity using the commercial credit card and, in some embodiments, purchases made through other purchasing channels. In addition, environmental advisory data, such as suggestions for environmental improvements, environmental educational information or the like may be determined based on the purchases. Additionally, environmental rebates, such as carbon offsets may be determined based on the purchases/purchase amounts and customized based on commercial entity preferences.”

This is a business method patent using ‘computer program products’ (i.e., software). Is this patent good because it helps save the planet? Is it bad because it is owned by a large corporation? Or bad because it’s a business method patent and some folks have the notion that they shouldn’t be allowed? Or bad because it’s software and other folks have the notion that software patents are the death of innovation? It makes my head explode pondering this quandary.

Carbon Sequestration

US Patent 8,308,911, “System and method for atmospheric carbon sequestration,” from November 2012, issued to inventor Michael Cheiky and assigned to Cool Planet Biofuels, LLC. (Anyone remember the early 70s when the rage was global cooling and a new ice age? Just wondering.) “This invention relates to systems and methods for converting biomass into highly inert carbon. Specifically, some embodiments densify the carbon into anthracite-style carbon aggregations and store it in geologically stable underground deposits. The use of certain embodiments yield a net effect of removing atmospheric carbon via the process of photosynthesis and converting it into hard coal, which can be stored in underground beds that mimic existing coal deposits which are known to be stable for thousands of years.”

Carbon Reduction

US Patent 7,919,290, “Bio-recycling of carbon dioxide emitted from power plants,” issued in April 2011 to John Offerman and Hugh McTavish; they retained ownership of the patent. Their invention “provides a method to decrease emission of carbon dioxide from combustion of fossil fuels or other hydrocarbons and to enhance the efficiency of methane production from anaerobic biodigesters. The invention involves feeding carbon dioxide from the exhaust gas of hydrocarbon fuel combustion to an anaerobic biodigester where biomass is anaerobically fermented to produce methane. Carbon dioxide is an electron acceptor for anaerobic fermentation, and thus some of the carbon dioxide is reduced to methane, which can again be used for fuel. In this way, at least a portion of the exhaust gas CO2 is recycled to form fuel methane instead of being released into the atmosphere. Thus, the net CO2 emission from burning a given amount of fossil fuel is decreased. Adding carbon dioxide to an anaerobic fermentation also increases the efficiency and amount of methane production in the fermentation.”

We will explore toxic emissions and fine particulate matter reductions technology that might have played a role at Las Brisas in an upcoming post.