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Fwd: McIlvaine Co. offer

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McIlvaine Company
ANSWERS TO IMPORTANT POWER PLANT QUESTIONS OF THE MONTH

Here is a copy of our “Power Plant Questions of the Month”. We propose to email it to you each month for the next year free of charge. We believe if we can demonstrate the value of our information you will want to know more about our Power Plant Knowledge system. We think that one of these months you will find one of these subjects to be important enough to want to explore it in depth and then we can make our sales pitch.

To sign up for your free subscription just click on the reply button on your browser and reply to this e-mail with a “yes” typed in the response.

For more information on the McIlvaine Company see our web site at: http://www.mcilvainecompany.com

POWER PLANT QUESTIONS OF THE MONTH

WILL POWER PLANTS HAVE PROBLEMS MEETING THE 2003 NOx REDUCTION REQUIREMENTS?
The answer is maybe. The bigger utilities with a number of affected plants are faced with only a few outages over the next three years. AEP and TVA have lined up partners in order to nail down the availability of engineering and equipment. But some of the mechanical contractors are already reporting full shops and a heavy workload. The secret is going to be maximum effort now to finalize plans and line up contractors. Those utilities who wait until 2001 are going to be out of luck.

WHAT KIND OF OPERATIONAL PROBLEMS COULD I HAVE WITH NOx CONTROLS?
Combustion modifications can result in accelerated tube wastage and unburned carbon in the fly ash. SCR problems include arsenic poisoning of the catalyst and ammonia slip. In fact, California and Massachusetts are toying with regulations to require zero ammonia emissions. But even absent regulations ammonia can cause problems. It can plug up your air heater and it can contaminate your fly ash. Buyers will definitely react negatively to ammonia contaminated fly ash? Some of the vendors say their methods of ammonia distribution and control eliminate this problem. Others say the answer is a staged system.

We are not going to devote too much attention to NOx issues in this Overview because we have a NOx Chat Room with detailed discussions of all these issues. It is free and easily accessible on our web site.

To go to the NOx Chat Room click here: http://www.mcilvainecompany.com/discuss.

IS THE AVERAGE UTILITY OVER REPORTING NOx AND SOx?
Many utilities are actually emitting less NOx and SOx than they are reporting. Flows are actually 5% lower than instruments are indicating. This could be worth $ millions per year to the medium size utility.

DO I HAVE TO CHANGE CEMS DUE TO PART 75 AMENDMENT?
EPA has amended sections of Part 75 to provide more accurate measurement of NOx mass emissions. The question is whether to upgrade from an emission rate monitoring system to a mass monitoring system or whether it is better to replace the system and start over. Newer analyzers do not confuse NO with total NOx . Keep in mind that the value of accuracy goes up substantially with the trading of NOx at $3,000/ton.

CAN YOU MEASURE MERCURY CONTINUOUSLY AND ACCURATELY ?
It appears that continuous emission monitors for mercury will be able to duplicate the wet chemistry methods within 20%. Don’t be surprised if within a few years both continuous mercury and mass particulate monitors are required for each power plant stack. Tests of mass particulate monitors on incinerators have been positive. A number of power plants in Europe are already using mass particulate monitors of the tape sampler type.

ARE PRECIPITATOR PARTICLE EMISSIONS PRECURSORS OF PM2.5?
One of the problems in quantifying PM2.5 emissions is going to be semantics. How is a large agglomerate of small particles which is emitted when rapping the precipitator classified? If it quickly disintegrates when it loses its electrical charge, isn’t it all small particles?

INFORMATION TECHNOLOGY
How important advances in IT instrumentation, controls, automation, monitoring and process optimization are changing the very nature of electric power generation. Jason Makansi advises that the individual information technology functions must be integrated into a cohesive system that communicates seamlessly with IT networks external to the plant. The ultimate goal is economic optimization.

IT changes and is integrated into the personnel organization and cultures-minimizing people, making work safer, focusing on results, moving towards predictive maintenance, pushing the envelope on operations and performance, breaking down barriers between departments (i.e. maintenance and operations). It will create “virtual plant staffs, crews and teams” responsible for multiple plants and will facilitate third-party service contracts. A 1400 MW coal-fired plant in Australia is supervised by two people on site during the second and third shifts. This will become commonplace in the future.

SHOULD YOU REPLACE PRECIPITATOR INTERNALS WITH BAGS?
The replacement of precipitator internals with bags at the State Line plant is a significant event. While other bidders were following the specs with bids on precipitator internals, Wheelabrator bid a conversion to a baghouse. The flexibility to burn a greater variety of fuels led Southern to select the baghouse conversion. This decision was followed by the Sheldon station award to ABB to replace the existing precipitators with fabric filters.

DO YOU HAVE TO WORRY ABOUT TITLE V AND THE TOTAL PARTICULATE EMMISSIONS?
The problem is that your present opacity monitor doesn’t tell you how much particulate is emitted during excursions. So it is going to be difficult to verify total mass emissions. Unfortunately your Title V permit probably limits you to a specific tons per year of particulate. But there are some simple steps to take to protect yourself. One is to do some stack testing during upset or start up and shut down conditions. If the emissions are only slightly higher than normal then you have some supporting evidence.

IS THERE A ROLE FOR WASTE BURNING IN MY PLANT?

While coal gasification is still a questionable option from a cost standpoint, the gasification of waste can be quite attractive. In parts of Europe power plants are forced to burn 10% biomass in each coal-fired boiler. Gasifying waste and using it as a reburn fuel provides both the economic benefits plus the reduction of NOx. But just simple fuel blending is in vogue. Connectiv is fueling one plant with chicken manure. Illinois Power will burn all the plastic pellets it can find.

WHEN IF EVER IS COFIRING GAS ATTRACTIVE?
The answer is that there are many situations that favor cofiring. In the ozone season it is a way to reduce NOx. During low load conditions the use of gas may be more economic than running the pulverizers and burning the lower cost coal. Most importantly you have a back up if your air pollution control or coal handling equipment fails at a time of high demand. Mississippi Power found that they could burn a combination of petroleum coke and natural gas more inexpensively than coal.

WHAT’S NEW IN GAS TURBINE COMBINED CYCLE SYSTEM COMPONENTS?
There is probably more new and useful technology being developed to improve the complete combined cycle system than there is in the turbines themselves. This is a pretty expansive claim since the new series of turbines has substantially higher output and efficiency. But a substantial part of the output and cost is found in the other components. New ways to cool and purify the intake air can substantially improve output and lower life cycle costs. As they say the devil is in the details. The disc centrifuge manufacturers have MADE improvements in fuel purification. The cooling tower people have more efficient packings.

There is even a better access door you should consider rather than let each component supplier furnish a hard-to-open home grown design.

For more information on the Power Plant Knowledge System click here: http://www.mcilvainecompany.com/PPKS.htm

To sign up for your free subscription to the Power Plant Questions of the Month just click on the reply button on your browser and reply to this e-mail with a “yes” typed in the response.

McIlvaine Company
2970 Maria Avenue
Northbrook, IL 60062
Ph: 847 272-0010
Fax: 847 272-9673

E-Beam Stack Gas Scrubbing

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This might be titled, “Son of Ebara”, for those of you familiar with the history. It appears that dramatically better performance may be possible.

This text was provided to me by a private development group with access and connections to the new e-beam technology that is mentioned. I’ve edited the letter to remove some of the proprietary details. Even so, important ideas are disclosed. I would ask that you be especially careful not share it with anyone outside your company (as with all UFTO materials). If you’re seriously interested in pursuing this, I will put you in touch with the sources.

———————————————-

Below, please, find a short overview of both old and new developments in e-beam processing of industrial exhaust gases.

E-Beam Processing of Industrial Exhaust Gases

— Background
In the past few years new methods of decomposition of VOCs as well as inorganic compounds in flue gases have been developed, primarily involving low-temperature, non-equilibrium plasmas used to selectively decompose organic molecules. The high concentration of electrons, ions, excited species and radicals make these plasmas well suited for driving decomposition reactions that otherwise could be initiated only at very high gas temperature.

Such plasma methods are of particular interest in the decomposition of dilute concentrations of halogenated organic compounds in carrier gas streams such as dry or wet (about 10% relative humidity) air. This type of gaseous waste stream is encountered for example in vapor extraction from soil, air stripping from contaminated water and air pollution control.

Low temperature, non-equilibrium plasmas can be generated by electron beams. They operate at atmospheric pressure in large volumes and in a highly controllable fashion making very high throughput possible. It has been also demonstrated that electron beam becomes even more efficient in decomposition of certain VOCs when combined with certain type of electrical discharge.
Advantages of e-beam induced decomposition over thermal processes become even more pronounced at dilute concentrations of VOCs in the exhaust gases. Because of the high non-equilibrium level of ionization and the selectivity of plasma-chemical decomposition processes the energy required for a given decomposition of dilute concentrations of “electron hungry” VOCs can be 10 to 100 times less than in thermal processes such as incineration, where energy is channeled to all molecules in the gaseous waste stream.

— The EBARA Experience
The Electron Beam Dry Scrubbing (EBDS) process has been first proposed as an efficient method for the simultaneous removal of SO2 and NOx from industrial flue gas in early 1970s. In this process, the e-beam energy generates high concentration of oxidants (OH, HO2, O3) converting SO2 and NOx to nitric and sulfuric acid which in turn form solid powder of ammonium nitrate and sulfate in the presence of added ammonia (NH3).

The Japan Atomic Energy Research Institute and the University of Tokyo have carried out the first research on EBDS in 1970. Follow up technical development by EBARA Corporation lead to the first 10,000 Nm3/hr pilot plant built for a sintering plant at Yahata Works Nippon Steel Corp in 1977. At this plant a flue gas at temperatures T=70-90 C containing 200 ppm of SO2 and 180 ppm of NOx has been treated by 2 x 750keV/45kW e-beam accelerators.

In the US the first and only EBARA-process demonstration unit with a maximum flow rate of 30,000 Nm3/hr has been put in operation in June 1985 at a coal fired power plant in Indianapolis, Indiana. At this plant 2 x 800 keV/80kW electron accelerators has been employed treating 1,000 ppm of SO2 and 400 ppm of NOx in a flue gas at temperatures T=66-150 C.

In December 1985 a 20,000 Nm3/hr pilot plant has been built at Badenwerk, Karlsruhe, FRG at 550 MW coal fired facility employing two 300KeV/90 kW accelerators to treat 50-500 ppm of SO2 and 300-500 ppm of NOx in 70-100 C exhaust gas. In early 1990s similar e-beam treatment pilot units have been built in China, Poland and Russia.

One of the main limitations of EBARA process has been a considerable energy requirement for oxidation of SO2/NOx in an air stream, which amounts in average to about 10 eV/molecule. For a coal fired 300 MW electrical power plant this translates to 12 MW (4% of the electrical power generated by the plant required e-beam power. Back in 1980s the most powerful accelerators were below 100 kW, so 12 MW installation would require 120 x100 kW accelerators and the total accelerator costs in the access of $180 mln. were prohibiting.

— What’s New
A new generation of powerful accelerators manufactured in Russia which can deliver 1MW of e-beam power for the cost of about $1.5 million per unit, can already reduce cost of EBARA process by order of magnitude.

Moreover, a synergetic approach combining electrical discharge and electron beam may allow another tenfold decrease in flue gas processing cost. This is done by essentially substituting much less expensive power of corona discharge for most of the expensive e-beam power. This process maintains all the advantages of e-beam processing such as stability of operation and uniform treatment of large volumes and high mass flows of flue gas — for a fraction of cost compare with e-beam treatment alone. Note that corona discharge alone, without e-beam stimulating effect, suffers from intrinsic non-uniformities and instabilities which greatly reduce its efficiency for industrial scale applications.

Experiments on SO2 oxidation in e-beam stimulated corona discharge have been conducted. We were investigating the plasma chemical processes in an electron beam driven plasma reactor for efficient decomposition of SO2 , NOx or any VOC in carrier gases at atmospheric pressures.

The reactor used an electron beam to stimulate corona discharge at sub-breakdown pulsed electric field. A combination of e-beam and superimposed electrical field in the form of stimulated corona discharge creates plasma with highly controllable electron density and temperature and therefore highly controllable chemical reaction rates.

Synergetic effect of SO2 decomposition by the combined action of e-beam and corona discharge was estimated by the coefficient K equal to the ratio of the discharge energy Wc, consumed from high-voltage source, to the energy Wb deposited by electron beam within the volume of the discharge:
K = Wc / Wb

It has been demonstrated that under certain experimental conditions the energy of discharge consumed from high-voltage source can exceed e-beam energy input by more than 300 times. In other words, a low cost high-voltage rectifier instead of a high-cost electron accelerator provided about 99.7% of the flue gas ionization energy. As a result the same SO2 decomposition effect in e-beam stimulated corona discharge can be achieved with 300 times lower e-beam power compare with irradiation by e-beam alone.

There some indications that shorter e-beam pulses and higher discharge threshold voltage Umax may also lead to the significant decrease of energy cost per oxidation of one SO2 molecule from a typical value of 10 eV/mol down to 3 or even 1eV/mol. However, even at the lower Umax values rather efficient SO2 oxidation process is taking place.

The main purpose of these initial experiments on SO2 oxidation was to demonstrate significance of synergetic effect in e-beam stimulated corona discharge. Discovered synergetic effect allows efficient SO2 decomposition under the conditions when only 0.3% of the total ionization energy is provided by an electron beam with the rest coming from a low cost electrical discharge. Further experiments are necessary to determine the optimum conditions for most efficient decomposition of SO2./NOx mixtures, as well as VOCs in industrial exhaust gases.

We are open to any form of collaboration with a US utility company or research organization, which would enable us to continue these very promising experiments.

I look forward to your comments and suggestions.