Sodium Bicarbonate, Lime, CDS and Regulations were among the Topics covered on the First Day of the Industrial MACT Webinar
In 60 days or so we will know the specific changes for the final Industrial MACT. Correction-- we will know what is final until it is changed again. Unfortunately it will be three more years to find out if litigants are successful in causing changes. However, it will take three years to install the equipment and run it long enough to make sure of compliance. So it would seem there are two choices. Litigate and gamble you won’t have to shut down your plant or go ahead with the assumption that the rule will stand.
The individual presentations are linked as follows:
Shiaw Tseng, Graymont, provided performance data based on circulating dry scrubber (CDS) systems using lime. High removal efficiencies for HCl and mercury have been achieved. The units have a relatively small footprint and have been installed in over 200 plants with the largest operating system being 300 MW. Specific performance at AES, Virginia Tech, Medical College of Ohio, and Graymont Pleasant Gap demonstrate the ability of this technology to meet the proposed MACT requirements.
CDS Systems for Industrial Boilers
Carroll "Mack" W. McGuffey III, Associate at Troutman Sanders LLP, told the participants that it is unlikely that the final rule will be delayed by lawsuits. The litigants can petition to stay the rule until the litigation is complete but the D.C. Circuit Court is unlikely to do so. So the clock will be ticking and compliance will be required in 2014. The lawsuits can focus on several issues. One is the lack of five or more sources achieving the limits on any one pollutant. Another is the argument that a source which achieves the limit on one pollutant but not another is not a valid example.
Industrial Boiler MACT Proposed Rules and Compliance Strategies
Mike Schantz, Director of New Business Development at Lhoist / Chemical Lime Company,
explained that all hydrated lime is not the same. Sorbacal SP performs much better than typical hydrated lime on HCl. Sources using Sorbacal injection should be able to meet the 3 ppm HCl anticipated limit providing temperature, moisture, competing acid gases (SO3 and HF) and CO2 are within the normal range.
Sorbacal Dry Sorbent Injection - a Low Capital Solution for HCl Control
Tony Jabon, Principal Consultant at Trinity Consultants, expects the final rule to have different emission limits than in the proposal. He also expects changes in the testing requirements. One option will be to switch fuels rather than make a capital investment. In fact 11,500 of the 13,500 units already use natural gas and will not have to make changes. For the other 2,000 now is the time to determine the availability and cost of alternatives. Emission controls don’t always work to specifications, so if you go the equipment route, leave enough time for testing and adjustment prior to the compliance date.
Boiler MACT - What Can We Do Now?
Dave Novogoratz, Business Development Manager for the Particulate Control Group at Babcock & Wilcox Power Generation Group, Inc., indicated that the requirement for PM CEMS for boilers over 250 MMBtu/hr and for CO CEMS add some new challenges. The CO limit requirements may require thermal oxidizers or CO catalyst for grate-fired units. Wet ESPs may have a place downstream of wet particulate scrubbers to meet the new PM requirements. ACI, SDA, scrubbers, fabric filters, and oxidation catalyst might be options for dioxin and furan control. Compliance will require a system solution that also takes into account other upcoming regulatory requirements.
Industrial Boiler and Process Heater MACT
Yougen Kong, P.E., Ph.D., Technical Development Manager at Solvay Chemicals, Inc., explained that trona can achieve up to 98 percent HCl removal while sodium bicarbonate can achieve over 99 percent while also achieving better than 90 percent SO2 removal. There is a modest price penalty for the sodium bicarbonate. On the other hand, injection avoids major capital cost and is effective over a range of 275°F to 1500°F. Bicarbonate is being used at many waste incinerators in Europe and coal-fired power plants in the US.
Dry Injection of Trona or Sodium Bicarbonate to Mitigate HCl and SO2 from Industrial Boilers
Carbon, Spray Dryers, Biomass Boilers, CO Challenges and PM CEMS covered in Friday’s Industrial MACT Hot Topic Hour
The individual presentations are linked as follows:
Richard (Rich) Miller, Vice-President of Business Development for Utility Systems at ADA Environmental Solutions (ADA-ES), showed timelines which dictate that boiler operators start mercury testing soon. There are lots of unknowns due to the wide variety of fuels and boiler configurations. With the potential of large carbon needs by the utility and cement industries, supply could be an issue. Mercury reduction guarantees are going to be tough to provide since the need is a mass emission level and not a percent removal. Furthermore the 0.2 lbs/TBtu limit for biomass boilers will be difficult to measure as well as guarantee.
Industrial Boiler MACT Rule - Impact and Control Options for Mercury and Dioxins/Furans
Robert (Bob) Fraser, Senior Technical Director at AECOM Environment, discussed AECOM’s experience to date with the boiler MACT. He indicated that no one plant is now demonstrating the ability to meet all the pollutant requirements. There is very little data on CO and dioxins. It may be necessary to install back end CO and dioxin controls. These could be quite expensive. Minimizing the time at which the gas is in the 800-460 degrees F range by quenching should be effective in avoiding dioxin formation, but this is not an option where downstream fabric filters are being operated. One big question is whether a source which switches fuels to meet the MACT would then be a “new MACT source.” If a new permit is required because of fuel switching, then it is very possible that the source would be considered “new.”
Experience to Date with Boiler MACT - Potential Control Alternatives
Jon Miller, Technical Support Engineer at Albemarle Corporation, explained that M-PACT is an equipment package to inject activated carbon at much lower cost than a custom design. The first M-PACT unit was sold in 2007 and is providing reliable 90 percent mercury reduction. There are a number of components in the larger systems which are critical. One is the choice of blower for the pneumatic conveying. A regenerative blower is less expensive but has a lower pressure output and is less tolerant of dirty environments. A Roots type PD blower is more expensive but capable of higher pressures and will tolerate some dust.
M-PACT Unit, Mercury Control Equipment Optimally Designed for Industrial Boilers
David W. South, Manager of Business Development at Amerex, drew from a considerable bank of experience the company has gained with some 50 MACT related boiler installations in the last five years. One unit on a PC boiler with carbon injection and a fabric filter is using 2.2 lbs/MMacf of B-PAC. Inlet mercury is 20 lbs/TBtu versus 2.5 lbs/TBtu on the outlet. Another with only 2.0 lbs/MMacf is reducing mercury from 25 lbs/TBtu to less than 2 lbs/TBtu.
Industrial MACT - Impact and Control Options
J. Patrick Stevens, Associate and Senior Consultant at Golder Associates Inc., told participants about a survey of 16 biomass-fired boilers in the wood products industry to determine whether or not they would meet the proposed existing source Boiler MACT limits for biomass-fired boilers. CO was one pollutant that would create a challenge. Four boilers would require no improvement. Twelve boilers will require from 13 to 79 percent reduction in CO. Nine of these would require end of pipe controls while three could improve fuel handling and combustion.
Impact of Proposed Boiler MACT on 16 Biomass Boilers
Dan Kietzer, Environmental Market Manager at Sick Maihak, Inc., covered CEMS for particulate and CO and CEMS requirements. The company has sold more than 50 PM CEMS using the scattered light principle to power plants in the U.S. Some were to meet consent decrees which mandated installation of PM CEMS. The scattered light approach can provide accurate mass measurement in either dry or wet stacks. In wet stacks the sample gas is withdrawn and heated prior to measurement. An insitu CEMs for CO can also measure CO2 and H2O.
Industrial Boiler MACT: CEM Requirements
The BIOS, ABSTRACTS and PHOTOS for both days are linked below.
BIOS, ABSTRACTS, PHOTOS - November 18-19-2010.htm