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U.S. Navy's Final Report

Katec Aerosolv Technology Field Test Demonstration

Summary of Results

I. BACKGROUND

Katec Inc. entered into an agreement with the U.S. Environmental Protection Agency (EPA) and the California Environmental Protection Agency for federal verification and state certification of the Aerosolv technology. The technology consists of an aerosol can puncturing/draining device that is threaded into the large bung hole at the top of a 55-gallon drum; a coalescing filter assembly that is threaded into the small bung hole of the drum; and a 30-gallon drum carbon filter canister, see enclosure (1) of Appendix I. Liquids discharged from the puncturing/draining device are collected in the collection receptacle. Non-condensable gases and volatile fractions are diverted through the coalescing filter and adsorbed onto the carbon. Empty cans resulting from the process are recycled as scrap metal.

In November of 1996, Katec approached the U.S. Navy for assistance in developing and performing the Field Test Demonstration outlined in the Field Test Plan. Katec selected the Navy for five reasons:

1.  

The Navy is the largest generator of hazardous waste aerosol cans in California.

2.  

California Assembly Bill 483 authorized hazardous waste aerosol can generators to use certified aerosol can recycling technologies without extensive permitting or authorization requirements. Commander Naval Base, San Diego (CNBSD) and the Navy Public Works Center (PWC), San Diego, Environmental Department were searching for an aerosol can recycling technology manufacturer who would be willing to obtain certification in the State of California. CNBSD and PWC offered to provide a test demonstration site, a large inventory of aerosol cans, and the labor to operate and test the Aerosolv technology.

3.  

The Navy generates a larger variety and diversity of aerosol can products than any other industrial user in California.

4.  

The Navy was instrumental in the development of the Aerosolv technology at the Naval Operations Base in Norfolk Virginia.

5.  

CNBSD and PWC are extremely cognizant of the regulatory issues associated with aerosol can management. For further discussion of regulatory status, please see discussion at the end of this document.

PWC began conducting the Field Test Demonstration in accordance with the approved Field Test Plan on August 5, 1998. The test concluded on November 19, 1998. This document summarizes the results of the demonstration conducted by the Navy.

II. FIELD TEST OBJECTIVES

1.  

Removal

a.  

Removal of hazardous waste to 3% of capacity: Determine the ability of the technology to remove hazardous waste such that less than 3% of the original capacity of hazardous waste remains. This is consistent with the federal definition of an empty container.

The results indicated that 98.6% of the cans contained less than 3% residual by weight of the total capacity after puncturing. This residual was comprised of both hazardous and non-hazardous material.

b.  

Removal of hazardous waste to the maximum extent practical: This is consistent with California's specific aerosol can regulations for hazardous waste. California developed specific regulations for aerosol cans because none existed previously.

DTSC and PWC representatives noted that each of the cans processed were emptied to the maximum extent practical.

c.  

Removal efficiency: Determine the 90% confidence limit of the mean removal efficiency.

The test results indicated that the Aerosolv technology captured 95% of the total product discharged. Removal efficiency calculations are presented in Appendix XIII.

2.  

System Capture Efficiency

a.  

Determine the percent of gaseous and liquid contents removed from the processed cans that is captured by the Aerosolv technology.

Mass balance discharge and Aerosolv system collection results indicated that 95% of the materials discharged were removed and captured by the Aerosolv technology.

3.  

Carbon Filter Effectiveness

a.  

Determine the total mass of the contents of aerosol cans processed by the Aerosolv technology resulting in carbon filter breakthrough emissions and the mass resulting in carbon filter changeout in accordance with criteria established in the Field Test Plan.

For each type of material processed, an analysis was conducted to calculate the cumulative number of grams discharged when the carbon filter exhaust monitor reached 100,000 ppm. Not surprisingly, the values varied depending on the material; indicating that there is no obvious or direct correlation of mass discharge and filter saturation. For the five filters utilized during the paint processing, the filters emitted 100,000 ppm at an average of 16,800 grams of paint discharged. For corrosion preventative compound (CPC), 42,000 grams was discharged prior to the first filter emitting 100,000 ppm. The 100,000 ppm threshold was not reached on the second CPC filter after 35,000 grams was discharged. The filter for the Brakleen never reached the 100,000 ppm threshold even though 46,000 grams was discharged through the unit. In fact, the Brakleen filter never exceeded an exhaust emissions reading in excess of 3.88 ppm.

Target compounds were not detected at the 90% carbon filter effectiveness (100,000 ppm) threshold established in the Field Test Plan for carbon change-out. As such, a more appropriate basis for determining carbon change-out is when emissions of target compounds from the carbon bed exhaust are detected in the breathing zone at concentrations exceeding Occupational Safety and Health Administration (OSHA) permissible exposure limits (PELs). This action point for carbon changeout was never reached during the field test. Based on Field Test results, PWC recommends that carbon changeout occur after continuous or sustained processing well in excess of 2,000 cans (for more detailed information see Appendix XIII).

b.  

Measure the total organic vapor concentrations in carbon filter breakthrough emissions and assess their risks to worker health and safety.

With respect to any emissions coming off of the carbon filter, no target compounds were found at laboratory reporting limits; thus the emissions were propellants. Health risks associated with the propellants are identified in Table 1, Enclosure (3), of Appendix I. Monitoring results support the conclusion that employees were not exposed above OSHA PELs, National Institute of Occupational Safety and Health (NIOSH) recommended exposure levels (RELs) or American Conference of Governmental Industrial Hygienist (ACGIH) RELs.

c.  

Assess the adequacy of the established standard operating procedures in determining when the carbon filter needs replacement.

The standard operating procedure for the Aerosolv unit recommends changing the filter when the granules contained within the colorimetric indicator change color from magenta to black. The manufacturer designed the indicator to be sensitive to the target compounds and not to propellant gases. As noted in the field logs the colorimetric indicator was monitored during the Test Runs and changes in color were observed. At no time was any indicator observed to turn black. These observations support the field monitoring data that target compound saturation was never reached. At the 100,000 ppm threshold carbon beds were still effective in capturing target compounds and minimizing worker health and safety concerns (see specifically the Brakleen Test Runs). PWC recommends that additional language in the SOP clarify that the colorimetric indicator color change is gradual, but saturation is not indicated until it turns black.

4.  

Assess Worker Health and Safety in Operating the Aerosolv Technolog

a.  

Determine the capability of the Aerosolv technology to operate such that the vapor/gaseous emissions within the operator's breathing zone do not exceed the allowable daily exposure.

Workplace monitoring results indicated that PWC employees were not exposed to vapor/gaseous emissions within the operator's breathing zone above OSHA PELs. Breathing zone exposure results are contained in Appendix I, Section 3 of the Report.

b.  

Determine the capability of the Aerosolv technology to operate such that the vapor/gaseous emissions within the operator's breathing zone do not exceed other regulatory limits.

Workplace monitoring results indicated that PWC employees were not exposed to vapor/gaseous emissions within the operator's breathing zone in excess of other occupational exposure limits recommended by NIOSH and ACGIH. Breathing zone exposure results are contained in Appendix I, Section 3 of the Report.

c.  

Determine the potential for emissions from operation of the Aerosolv technology to exceed 10% of the LEL.

Workplace monitoring results indicated that 99.96% of the total data points collected were less than the lower explosion action limit (LEL) of 1% (10,000 ppm). LEL monitoring results are contained in Appendix I of the Report.

d.  

Determine the effectiveness of the technology in preventing releases of the liquid contents of the aerosol cans.

II. FIELD TEST RESULTS

Objective 1a: Removal of Hazardous Waste to 3% of Capacity

PWC began collecting aerosol cans for the Field Test Demonstration in November of 1996. Over 25,000 cans were collected and segregated according to class, family, and species as indicated in the PWC Standard Operating Procedure #931-96-006, Aerosol Can Management. Due to changes in the development of the Field Test Plan and regulatory restrictions regarding treatability studies and the storage of aerosol cans, the cans were sorted and inventoried on three separate occasions. The final segregation and inventory was conducted in response to the November 20, 1997 Draft Field Test Plan. As a result of that segregation and inventory process, PWC provided a list of the various types and constituents contained in each can to be evaluated. DTSC had originally proposed that:

1.  

Test Run #3 be conducted solely on So-Sure Lacquer Green 14110;

2.  

Test Run #4 be conducted on Eco-Sure Gray Spray Paint 16099;

3.  

Test Run #5 be conducted on either Eco-Sure or So-Sure paint;

4.  

Test Runs #6 and #7 be performed on Aerokroil penetrating oil; and

5.  

Test Runs #8 and #9 be performed on Polytech TG-452 aerosol cleaner.

PWC personnel segregated the paints into Eco-Sure and So-Sure paints and demonstrated that the each type of paint contained similar constituents. PWC also demonstrated that So-Sure CPC was more prevalent than Aerokroil and Brakleen was a more prevalent than TG-452. As a result, PWC requested and received verbal permission to:

1.  

Evaluate any approved type of So-Sure paint in place of the green lacquer;

2.  

Evaluate any approved type of Eco-Sure paint in place of the gray spray paint

3.  

Substitute So-Sure CPC for Aerokroil; and

4.  

Substitute Brakleen for TG-452.

Katec further requested that the field test evaluate 3-25% full cans as opposed to full cans as originally requested by DTSC. Katec made this request because in the real world, very few cans in the spent aerosol can waste stream are more than 25% full. In fact, most are 3% to 15% full. However, because of time constraints, and with the approval of DTSC, full cans were processed through the carbon beds. In fact, DTSC representatives requested the processing of full cans during Test Run #1 (Eco-Sure paint). DTSC later revised the Field Test Plan to incorporate these requests.

PWC performed Test Run #1 on 352 Eco-Sure High-Solids enamel paint cans and Test Run #2 on 1132 So-Sure paint cans. At the conclusion of Test Run #2, PWC requested to bypass Test Run #3 based on the length of time required to conduct the previous tests, the shortage of Eco-Sure High-Solids enamel paint cans with between 3% and 25% residual prior to puncturing, and the apparent collection of sufficient data. DTSC permitted PWC to proceed with Test Run #4 while it evaluated the need to conduct Test Run #3.

At the conclusion of Test Run #4 DTSC decided that Test Run #3 was necessary and further requested that PWC not proceed with any other Test Runs until 75 paint cans were randomly selected and cleaned for tare weight determination. PWC personnel consulted with DTSC representatives and selected 100 post-treated cans from Test Run #2 for the purpose of cleaning and tare weight determination. These cans were collected in a separate box and put aside. DTSC representatives then assisted PWC personnel in selecting an appropriate can opener and observed the can opening and cleaning process.

During the cleaning process, PWC and DTSC representatives realized that the polymerized paint solids adhered to the side of the cans was extremely difficult to remove. At that time PWC inquired as to the validity of including the weight of this dried, solid, polymerized, non-hazardous material in the tare weight determination. PWC argued that the 3% criteria outlined in 40 CFR 261.7 did not include non-hazardous material. The polymerized paint solids discovered were definitely non-hazardous.

As such, in accordance with page 4 of the Field Test Plan, PWC requested that the tare weight procedure be modified because it was inadequate with regards to the verification process. Specifically, the procedure as written included the weight of this non-hazardous residue.<

Paint

First Evaluation: So-Sure paint cans from Test Run #2, deficient of exterior paint, tape, labels, or other discretionary debris, were selected in the presence of DTSC personnel to ensure the integrity of the tare weight results. Over 1100 So-Sure paint cans were evaluated. The majority of these cans contained less than 15% product (estimated based on pre-treatment weight) prior to treatment. These cans were collected over a period of two years. PWC selected So-Sure paint because the chemical formulation of So-Sure paint represents the most common type of paint used both commercially and by the military.

The random selection process resulted in evaluation of So-Sure paint cans with post-treatment weights less than 110 grams. This sampling represented 60% of the total So-Sure paint can pool. The cans selected had post-treatment weights ranging from 96.32 grams to 109.96 grams, a variance of 13.64 grams. Original nominal capacity weights ranged from 283 grams to 361 grams with an average of about 300 grams. Given that the lowest post-treatment weight recorded for the entire paint can pool was 94.00 grams, it was reasonable to suspect that the tare weight of the paint cans would probably be less than 94.00 grams. Further, using an average nominal capacity weight of 300 grams, one could quickly determine that 3% of the original contents would equate to approximately 9.0 grams.

Based on these preliminary calculations, PWC hypothesized that cans with post-treatment weights in excess of 103 grams (94 grams of tare weight plus 9 grams of residual) would not meet the 3% criteria. Therefore, 33 of the 75 cans would not meet the 3% criteria. PWC further hypothesized that the residual percentage would increase linearly as the post-treatment weights elevated above 94.0 grams. As such, a can registering a post-treatment weight of 97.0 grams would maintain a 1% residual volume, a can registering a post-treatment weight of 100.0 grams would demonstrate a 2% residual volume, a can registering a post-treatment weight of 103 grams would demonstrate a 3% residual volume, and so on. As such, PWC expected over 40% of the So-Sure paint cans randomly selected to retain residual volumes in excess of 3% because their post-treatment weights exceeded 103 grams.

Tare weight results (provided in Appendix II) did not support our hypotheses. Over 75% of the cans were emptied by the Aerosolv technology to less than 1.5% of their original capacity. Over 90% of the cans were emptied to less than 2.0% of their original capacity. All of the cans were emptied to less than 3.0 % of their original capacity. Further, the results showed no relationship between post-treatment weights and percent residual remaining. Cans with post-treatment weights of 102 grams had percent residual volumes between 1.3% and 1.8%, while cans with average post-treatment weights of 109 grams had percent residual volumes between 0.4% and 1.8%.

Definite trends highlighted by the results indicate that the percent residual remaining in the can is truly a function of the can and the technology design. During the processing of each can, DTSC and PWC representatives noted that the design of the Aerosolv technology puncturing device punctures the can just above the lip formed at the top of the can. The contents of the can are allowed to drain through the hole; however, the cup that's created captures material collected in the lip of the can. This minimal volume of material is consistent for each can. Therefore, the percentage of material that remains becomes a function of the total original capacity of the can and not of the technology's ability to empty specified types of material. Analysis of the tare weight results indicates that all seven cans with percent residual volumes over 2% had total original capacities less than 300 grams.

Second Evaluation: DTSC selected a combination of Eco-Sure and So-Sure cans for the second tare weight evaluation. The cans selected were as follows: 19 Eco-Sure High-Solids enamel paints form Test Run #1, 43 So-Sure paint cans from Test Run #2, and 13 Eco-Sure High-Solids enamel paints from Test Run #3. Eco-Sure High-Solids enamel paint cans from Test Run #1 contained less than 15% material prior to puncturing (estimated based on pre-treatment weight) and were collected over the course of two years after discard. The nature of the So-Sure paint cans selected was described above. Eco-Sure High-Solids enamel paint cans selected from Test Run #3 also contained less than 15% material prior to puncturing (estimated based on pre-treatment weight). However, these cans were only collected over the course of one month after discard. PWC personnel segregated and collected the cans for Test Run #3 from cans that were recently relinquished because they had previously run out of Eco-Sure High-Solids enamel paint cans that they deemed appropriate for evaluation. In addition, three basic differences exist between the Eco-Sure High-Solids enamel paints and the So-Sure paints:

1.  

Eco-Sure High-Solids enamel paints are military specification paints made specifically for the military. Commercial users are unable to obtain high solids content paints of this nature;

2.  

Eco-Sure High-Solids paint cans are lined with a protective internal coating. This coating was removed during the can cleaning process because paint stripper was used to remove the polymerized solids adhered to the protective coating. Therefore, the weight of the protective coating, which should be added to the tare weight of the can, is lost in the calculation;

3.  

Eco-Sure High-Solids enamel paints have two shaker balls per can as opposed to one in most cans. Two balls may be used to ensure proper dissolution of the additional solids present in the can.

Tare weight determination procedures were outlined and agreed upon by DTSC, Katec, and PWC, Appendix IV. Tare weight results supported the conclusions established in the first tare weight evaluation of So-Sure paint cans, Appendix V:

1.  

88% of the cans were emptied by the Aerosolv technology to less than 1.5% of their original capacity;

2.  

Only one can exhibited a post-treatment residual volume greater than 2.5%;

3.  

All of the cans exhibited post-treatment residual volumes less than 3.0%

4.  

Can number 273, the can with the highest post-treatment weight also had the highest tare weight: 116.83 grams;

5.  

Can number 750, the can with the second highest residual volume (2.34%) had one of the lowest post-treatment weights: 103.91 grams;

6.  

Can number 992, the can with the second highest post-treatment weight (113.23) had one of the lowest residual volumes: (0.47%).

In evaluating the military specification Eco-Sure High-Solids enamel paints, it was reasonable to suspect that the residual volume would be greater than that for the commercially common So-Sure paints. Katec and PWC questioned the validity of evaluating a product whose use is primarily limited to military applications. However, the parties agreed that utilizing data obtained from tests performed on these cans would provide valuable insight as to the capabilities of the Aerosolv technology. Katec and PWC also suspected (as discussed above) that cans of high-solids paints that were stored in a near-empty capacity for sustained periods of time would polymerize internally. In this case, one could not re-suspend the solids and they would be unavailable for application as a coating. Consequently, they would also be unavailable for discharge during aerosol can puncturing and draining. Therefore, these cans would retain a greater volume of residual than cans whose solids that did not have an opportunity to polymerize internally. Katec and PWC hypothesized that aerosol cans were not completely impervious to air and that oxidation and polymerization took place inside the cans. If this theory were valid, the residual results for Eco-Sure High-Solids enamel paint cans from Test Run #1 would be drastically different than those from Test Run #3. DTSC and PWC representatives witnessed part of this phenomenon when they investigated Eco-Sure High-Solids enamel paint cans immediately after puncturing and discovered that the cans had in fact allowed polymerized solids to adhere to the sides of the cans. PWC representatives noticed the phenomenon to a greater extent when comparing the amount of polymerization found in Test Run #1 cans to the lesser volume found in Test Run #3 cans. Evaluation of the tare weight results further highlighted the effect:

1.  

All 13 cans from Test Run #3 exhibited tare weight residual volumes between 0.8% and 3% with an average around 1.5%;

2.  

Cans with higher post-treatment weights demonstrated lower residual volumes (compare cans #10, #97, #122, and #132 to cans #44, and #45).

3.  

Five cans from Test Run #1 exhibited post-treatment residual volumes in excess of 3%. Two of these cans appeared to be missing a shaker ball and their tare weight results are suspect.

4.  

The 14 cans remaining had tare weight results between 0.8% and 3.0% with an average around 2.0%;

5.  

Cans from Test Run #1 had noticeably more polymerized solids adhered to the internal protective coating and the outside of the tube.

All of the Eco-Sure High-Solids enamel paint cans were emptied to the maximum extent practical; however, it was apparent that the Test Run #1 cans retained more residual volume than the Test Run #3 cans. Additionally, Test Run #1 cans were noticeably more difficult to clean than either Test Run #2 or Test Run #3 cans. Based on these observations, and in light of the fact that DTSC and PWC representatives witnessed polymerized solids adhered to the side of cans that were cut open immediately after puncture, PWC concluded that polymerization does indeed occur in aerosol cans during sustained storage.

Corrosion Preventative Compound

First Evaluation: For purposes of the first tare weight determination, PWC randomly selected 75 cans from one kind of CPC (Mil-C-81309E, Type III, Class 134A) to ensure the integrity of the tare weight results. This particular type of CPC is a military specification product containing chlorofluorocarbons (CFCs) that have been otherwise banned from commercial use.

Tare weight results indicated that percent residual volumes consistently ranged between 0.3% and 0.6% regardless of post-treatment weight. These data further support the data trends discussed with regards to paint cans. In this case, the type of material and the original total capacity of the can remained constant. Therefore, the only variable was the effect of the technology. From the results, PWC concluded that the technology consistently empties cans with liquid-only components to less than 1% residual.

Second Evaluation: Five types of CPC were evaluated during the Field Test Demonstration: Mil-C-81309D, Type II, Class 2; Mil-C-81309E, Type II, Class 134A; Mil-C-85054A, Type I, Class A; Mil-C-85054B(AS), Type I, Class 134A; and Mil-C-81309E, Type III, Class 134A. From these types DTSC selected 20, 18, 16, 5, and 15 cans respectively. Mil-C-85054B(AS), Type I, Class 134A and Mil-C-8504A(A3), Type I, Class A contained barium sulfate and were expected to demonstrate much greater residual volumes than the other types. All of the CPC types are military specification materials and contain CFC propellants. Materials with CFC propellants are no longer manufactured for applications outside of military applications. As such, the CPC products selected do not represent common commercial use. However, the selection of these products for the Field Test Demonstration assisted the research team in evaluating the effectiveness of the carbon filter and potential occupational health exposure.

Tare weight results indicated that CPC cans that did not contain barium exhibited residual volumes between 0.2% and 1.2%. These results were consistent with the results obtained in the first tare weight determination. CPC cans that contained barium exhibited residual volumes between 0.5% and 2.0%. These results were also consistent with expected results.

Brakleen

PWC randomly selected 75 cans of Brakleen, cleaned the cans with a naphtha solvent, allowed the cans to dry, recorded the tare weight results of each can, and determined the percent residual volume of each can. Tare weight results indicated that percent residual volumes consistently ranged between 0.3 and 0.5% regardless of post-treatment weight. These results paralleled the CPC results with one exception: more Brakleen cans demonstrated percent residual volumes around 0.3%.

Conclusions:

Based on the demonstration results, the Aerosolv technology has successfully demonstrated that it facilitates the emptying of aerosol cans to less than 3% residual as defined by this objective.

The design of the Aerosolv technology facilitates discharge of in excess of 97% by weight of the capacity of aerosol cans processed. The actual percentage of residual remaining in the can is a function of the technology and the can design. In this Field Test, three types of products were evaluated. For each type of product, the volume of liquid captured in the lip of the can was similar, approximately 0.5 cubic centimeters. However, the average percentage of residual remaining in the can for Brakleen was less than that for CPC, which was less than that for paint. Ironically, the total original capacity by weight for Brakleen exceeds that for CPC by over 100 grams. The original capacity by weight for CPC exceeds that for paint by over 150 grams on average. Because the paint total capacity is significantly less than the CPC or the Brakleen , the percent residual by weight remaining in the paint cans is greater (see discussion in the conclusion for Objective 1c below). However, in every case, the weight captured in the lip of the can is minimal and for 98.6% of the cans evaluated, the residual volume constitutes less than 3% of the total original capacity.

Of further interest, five of the 375 cans evaluated during this tare weight determination process that exhibited residual volumes greater than 3%, contained non-hazardous residuals that were present in a non-hazardous form prior to puncturing. All five cans were military specification Eco-Sure High-Solids enamel paint and all five were stored for up to two years in a near-empty capacity. In addition, the residual volume calculation for two of the five cans was suspect.

Objective 1b: Removal of Hazardous Waste to the Maximum Extent Practical

The Aerosolv puncturing/draining device is designed to receive inverted aerosol cans. This design promotes drainage of the contents of the can into the collection receptacle and coalescing filter as appropriate. The puncturing pin places a hole just above the lip of the can through which the contents are allowed to escape. The evacuation process is quick and efficient. Cans are depressurized and emptied to the levels represented in Objective 1a. Investigation of the processed cans allows one to quickly determine that the cans are emptied to the maximum extent practical. See Appendix XII for more detail.

Conclusions:

Based on the demonstration results, the Aerosolv technology has successfully demonstrated that it removes the contents of aerosol cans to the maximum extent practical.

Objective 1c: Removal Efficiency

The Field Test Plan was developed to ensure that the results obtained during the Field Test met the 90% confidence limit of the mean removal efficiency. Data from each aerosol can product class was obtained from the processing of the 375 cans described in the discussion for Objective 1a. The tare weight of each can was subtracted from the pre-treatment weight of each can to determine the weight of material contained in each can prior to processing (original content weight). The tare weight of each can was then subtracted from the post-treatment weight of each can to determine the weight of material that was not removed from the cans (residual weight). The resulting residual weight was then subtracted from the original content weight to determine the weight of material actually removed (removal weight). The removal weight was then divided by the original content weight and the result was multiplied by 100% to determine a removal efficiency.

Conclusions:

Field test results indicate that the removal efficiency objective is not a valid objective for purposes of this demonstration.

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