SCIENTIFIC REVIEW COMMITTEE MEETING
September 18, 2003
MEETING HIGHLIGHTS

Marty Kay welcomed the SRC members and the audience to the meeting. The topics listed below were discussed during the meeting.

Minutes of July 24th Meeting

Responses to Comments from July 24th Meeting

New and Updated BACT - Part B Listings

Other Business

The minutes of the July 24th meeting were approved as written.

AQMD stated that changes in the listings presented at the July 24^th meeting that had been agreed upon at the meeting, as well as any agreed-upon changes in the minutes from the prior meeting, had been made. Committee and audience members could check the final listings and minutes as posted on AQMD’s web site.

At the July 24^th meeting, discussion had continued regarding the revision in MSBACT for emergency diesel engines, and two questions had been left unresolved. These were: (1) source test requirements for emergency diesel engines implicit in the revised MSBACT and (2) comparability of the front half of AQMD Method 5.2 versus the dilution tunnel method used for PM measurement in U.S. EPA engine certifications.

Gary Rubenstein, who was not at the meeting, had researched the test protocols used for U.S. EPA engine certifications and had found that ISO 8178 is the required protocol and that this protocol specifies test cycle D2, a multi-load test cycle, for certification of emergency diesel engines. AQMD stated that its policy would be to require source testing on any uncertified engine and the probable test method requirement would be a single-load test (at the expected usual operating load) using Method 5.2 while also offering the option to employ the ISO protocol. AQMD also noted that the ISO protocol, while in many cases less stringent, would be somewhat challenging to apply in the field in that a load bank would be required in most cases to enable the multi-load testing and the dilution tunnel method is basically a lab method and thus difficult to apply in the field. AQMD added, however, that portable versions of the dilution tunnel method are being considered by both CARB and U.S. EPA.

Regarding comparability of PM measurements by AQMD’s Method 5.2 and the dilution tunnel method, AQMD had discussed this with SCEC and UC Riverside, both of whom had been involved in comparison testing of the two methods on untreateded engine exhausts. Both of these organizations reported that the front half of Method 5.2 compares well with the total PM measured by the dilution tunnel method.

AQMD had looked into two questions regarding the Kings County emergency diesel engine listing. A committee member had asked how the source tests could have found >100% removals of filterable and organic PM in some of the reduced-load tests. AQMD had re-examined the data and found that the data did indicate these >100% removals, which were apparently caused by the PM levels in the exhaust being less than the PM levels in the field blanks (i.e., as measured by the same method sampling the ambient air). However, to avoid confusion, AQMD had changed the values in the listing to 100%. Another committee member had noted that the catalyst vendor had guaranteed 98% VOC removal whereas the test data did not support this. AQMD had contacted the vendor and was advised that the vendor guarantees only 90% VOC removal. The listing was corrected in this regard.

Regarding the tunnel washer operated by Textek, which had been discussed at the July 24^th meeting, a committee member had asked what organics were present in the condensate leaving the process. AQMD had looked at the source test report and had found that the condensate at the time of testing contained, as micrograms per liter, 80,000 acetone, 500 toluene, and 1200 trimethylbenzene. (Howard Lange, AQMD)

This facility manufactures yachts. The primary emission sources are two large spray rooms used for manufacture of the boats. Boat manufacture consists of application of polyester resin/fiberglass mixture and gelcoats to molds that form hulls and other parts. VOC emissions from this process, of which styrene is the main constituent, are controlled by activated carbon beds, which are periodically regenerated on site. The facility has a total of five portable carbon bins, with two being used in parallel for each spray room. The spray rooms were constructed as permanent total enclosures and are vented to the carbon bins. Each carbon bin contains about two tons of carbon and is regenerated after every five days of operation. This system was desired by the facility owner in order to permit a production increase while keeping VOC emissions below the facility cap of 61 lb/day.

The regeneration system consists of a firetube boiler, which also serves as a thermal oxidizer. The carbon bin to be regenerated is disconnected from the spray room that it is serving and moved to the regeneration area, where it is connected to the boiler steam system. Steam is used to strip the adsorbed VOC from the carbon, and the steam/VOC mixture is directed to the boiler burner for destruction of the VOC in the boiler combustion chamber. The boiler is started up on natural gas, but once the carbon bed is heated up sufficiently, the VOC yield from the carbon takes over as the boiler fuel. Regeneration of one bed requires about six hours.

The facility source test included a test of one carbon bin while in service on a spray room and of the thermal oxidizer while regeneration of a bin was in progress. This test showed the carbon bin to be 93.4% effective in removing VOC from the vent gas and the thermal oxidizer to have a destruction efficiency of 91.4%, for an overall system efficiency of 85.4%. Marty Kay and Howard Lange had inspected the facility during normal operation and found the VOC control system to be correctly configured, in good condition and apparently working well based on lack of odor in the area. (Marty Kay, AQMD)

Discussion: Audience members asked how much the VOC control system had cost and how long a batch of carbon could remain in service. Another committee member, who was knowledgeable of the system, responded that it had cost less than $300,000 and the carbon life was typically five to seven years. An audience member asked whether Rule 1162 compliance was being achieved by use of compliant materials or by this VOC control system. AQMD was to determine the answer to this question and clarify the listing in this regard. A committee member asked how Rule 1171 compliance was being achieved. AQMD responded that it was being achieved by use of acetone as the cleanup solvent. The committee member requested that this be added to the listing, and AQMD agreed to do so. (Anoosheh Mostafei, Ship & Shore Environmental; Rita Loof, Radtech; Katy Wolf, IRTA; Marty Kay, AQMD)

This facility operates a combined-cycle gas turbine power plant consisting of three 9.9 MW gas turbine-generators fired on digester gas with unfired heat recovery steam generators, with the combined steam from the three units driving a 5.71 MW steam turbine-generator. The gas turbines were upgraded with newer combustors, which also increased their capacities, thus subjecting the facility to New Source Review. The BACT determination for NOx was based on Part D of AQMD’s BACT Guidelines, which requires control of NOx to 25 ppmvd@15%O2. The BACT determination for CO was 60 ppmvd@15%O2. This was based on the source test result, which showed the one gas turbine that was tested to produce a maximum CO level of 55.5 ppmvd@15%O2, which occurred at the lowest load at which it was to operate. (Howard Lange, AQMD)

Discussion: A committee member noted that the source test results as presented in the listing seemed to be incomplete for the lower of the two loads tested. The data at this load indicated "NM" for non-methane hydrocarbons, and there was no entry for particulate matter. AQMD responded that "NM" was intended to indicate "not measured" but was not sure why there was no entry for particulate matter. AQMD agreed to clarify the meaning of "NM" and determine why there was no entry for particulate matter and also clarify the listing in that regard. (Hal Taback, HTC; Howard Lange, AQMD)

This is a new 44-MW peaking power plant installed in Red Bluff in the Tehama County Air District. The plant consists of sixteen lean-burn natural gas engines, each rated at 3870 BHP. Each engine has a selective catalytic reduction (SCR) system for NOx control followed by an oxidation catalyst for control of CO and hydrocarbons. The BACT determination by the Tehama County APCD, which was based on CARB permitting guidelines for distributed generation, restricts NOx, VOC and CO to 9, 25 and 56 ppmvd@15%O2, respectively. AQMD’s only BACT guideline for stationary engines rated at 2064 BHP or above is found in Part D of the BACT Guidelines and restricts NOx, to 21 ppmvd@15%O2 multiplied by the engine HHV efficiency (%) divided by 33 and restricts CO to 33 ppmvd@15%O2. The Tehama County BACT determination thus is more restrictive for NOx and VOC than AQMD’s existing BACT guideline for this equipment category. (Howard Lange, AQMD)

Discussion:. A committee member questioned the ammonia slip data reported in the source tests, which showed ammonia emissions to be consistently less than 1 ppm. AQMD responded that this may be due partially to the presence of an oxidation catalyst and pointed out that the SCR system is probably achieving approximately 80% NOx control in this case, which allows operation with lower slip than higher-efficiency SCR systems that the committee has discussed in the past. (Hal Taback, HTC; Howard Lange, AQMD; Marty Kay, AQMD)

An audience member questioned whether these engines may be highly unusual in their emissions performance and whether the listing may therefore be too restrictive. AQMD pointed out that the listing reflects CARB permitting guidance for this equipment category. A brief discussion ensued, and it was the committee’s conclusion that the listing should stand. (Vlad Kogan, Orange County Sanitation Districts; Ted Guth, Consultant; Anoosheh Mostafei, Ship & Shore Environmental; Howard Lange, AQMD)

AQMD stated that it was making some changes in Parts C and D of the BACT Guidelines, the parts that apply to non-major sources. These changes consisted of updating the maximum cost effectiveness criteria for new or more stringent BACT guideline and adding/updating guidelines based on recent new or amended AQMD rules. (Marty Kay, AQMD)

AQMD stated its intent to update the maximum cost effectiveness criteria in Part C of the BACT Guidelines, based on the Marshall & Swift Equipment Cost Index published monthly in Chemical Engineering. (Marty Kay, AQMD)

AQMD stated its intent to add four new equipment categories reflecting recently adopted rules: Composting, with subcategory Co-Composting (Rule 1133.2), Resin Manufacturing (Rule 1141), Surfactant Manufacturing (Rule 1141.2) and Woodworking (Rule 1137). The new BACT in each case is basically compliance with the rule, although specific rule requirements were included in some cases. (Marty Kay, AQMD)

Discussion:. Regarding co-composting, an audience member and a committee member objected to including the specific rule requirements in BACT since they felt that the rule, as now written, is too stringent and is likely to be relaxed. AQMD agreed to strike the specific requirements in this case and just reference the rule. A committee member stated that the exemption of co-composting facilities in Note b is not a general exemption and applies only to one facility. AQMD agreed to look into this. Regarding Surfactant Manufacture, a committee member asked why soap manufacture was excluded. AQMD agreed to look into this. (Vlad Kogan, Orange County Sanitation Districts; Greg Adams, Los Angeles County Sanitation Districts; Marty Kay, AQMD)

AQMD stated its intent to update BACT guidelines for eight equipment categories.

Because the inspection & maintenance requirements in Rule 1173 were recently made more stringent, the BACT guidelines for Fugitive Emissions from Bulk Terminals, Natural Gas Plants and Oil and Gas Production Fields were updated to require compliance with Rule 1173, which replaces less stringent inspection & maintenance requirements in some BACT subcategories. Also, subcategory Process Drains was eliminated as it is now covered under new category Wastewater Treatment System. The guideline for Fugitive Emissions from Other Facilities continues to be compliance with Rule 1173, but the description of the category has been reworded to be consistent with terminology used in the rule. (Marty Kay, AQMD)

Discussion: A committee member suggested that the term "Bulk Terminal" be replaced with a more descriptive term. AQMD agreed to look into it. (Greg Adams, Los Angeles County Sanitation Districts; Marty Kay, AQMD)

Four categories of printing equipment have been combined under one new category, Printing (Graphic Arts). The four former categories, which are now subcategories, are Lithographic (Heatset and Non-Heatset), Flexographic, Rotogravure and Screen Printing. Letterpress Printing was added as a new subcategory. Compliance with Rules 1130 (1130.1 for Screen Printing) and 1171 was added to the guidelines as needed. (Marty Kay, AQMD)

Discussion: An audience member suggested that the guideline for lithographic printing specifying oil-base inks be expanded to include other low-VOC inks such as UV-cureable inks. A committee member pointed out that low-vapor pressure blanket and roller washes are still required in the BACT guideline for lithographic printing even though this requirement has been eliminated from Rule 1171. This committee member also asked whether the vapor pressure limit applies to VOC only or to all volatiles in the washes. AQMD agreed to look into these matters. (Rita Loof, Radtech; Katy Wolf, IRTA; Marty Kay, AQMD)

The equipment category Reactor with Atmospheric Vent was updated to include cross-references to the new guidelines for Resin Manufacturing and Surfactant Manufacturing, with which they also must comply. The category Water Treating, Oil/Water Separator was updated with "compliance with Rule 1176" and became a subcategory under a new category Wastewater Treatment System. All other water treatment system equipment is covered under a second subcategory, Other Equipment", for which the BACT guideline is just "compliance with Rule 1176".

AQMD stated that the next meeting is scheduled to take place at 1:00 p.m. November 20 in Room GB.

The committee stated a preference for room CC-2 for future SRC committee meetings. AQMD agreed to try to schedule CC2 for future meetings as available.

An audience member, Mr. Lee Terry of Prudential Overalls, addressed the committee with a concern about meeting the AQMD BACT NOx level of 30 ppmvd@3%O2 for Dryer or Oven on new laundry tumbler dryers that he wishes to install in another district. His specific concern was that the Part B listing of Aramark Uniform Services tumbler dryers was being sited as showing this NOx level is achieved in practice on laundry tumbler dryers whereas his research indicates that this is not the case. Mr. Terry had discussed the matter with burner and dryer manufacturers and with the designated contact person at Aramark and had concluded that manufacturers of low-NOx burners suitable for this application will not guarantee the 30 ppm NOx level and that these burners are high-maintenance items. He had also determined that these burners exceed OSHA noise standards. He further pointed out that there was no source test in the case of the Aramark dryers to show that they actually did achieve the 30 ppm NOx level.

Mr. Terry stated that he would submit written information to AQMD to substantiate his findings. AQMD thanked Mr. Terry for his comments and agreed to review the information and consider the matter. (Lee Terry, Prudential Overalls; Marty Kay, AQMD)

There was no further discussion, and the meeting was closed.