Accessibility of Low-Emitting Valves and Packing to meet Consent Decree Requirements in the Chemical Industry

Transcription

1 The Dow Chemical Company Accessibility of Low-Emitting Valves and Packing to meet Consent Decree Requirements in the Chemical Industry An End User Perspective By Dan DeVine

2 OVERVIEW ELP/Consent Decree Information Searching for Low Emission Products Results-Availability Challenges Increasing Qualified Low Emission Products Possible Implications for the Valve Industry

3 ELP INFORMATION The Dow Chemical Company has an Enhanced Leak Detection and Repair Program (ELP) for two production plants It imposes stricter requirements than normal Leak Detection and Repair (LDAR) regulations for Hazardous Air Pollutants (HAP) Includes increased monitoring frequency This presentation only addresses the low emission valve portion of the ELP

4 ELP INFORMATION Comparison of valve trigger requirements: HON Subpart H vs ELP Equipment Service HON ELP Valves Gas/Vapor or Light Liquid Service Leak definition = 500 ppm Monitoring frequency starts quarterly but can be reduced to annually with good performance Action Level 100 ppm (not a leak but must attempt repair) Leak definition = 250 ppm. The option to reduce from quarterly to annual monitoring is no longer based on source-wide leak rates; it is limited to individual good performing valves (meaning 2 years without a leak) and in exchange, the remaining valves must be monitored monthly for at least a year.

5 ELP INFORMATION Dow s decree was signed in November ELPs come from the EPA during negotiation of enforcement actions. Approximately 30 Dow plants at one site were inspected; 2 plants ended up with an ELP. EPA conducted fugitive emissions monitoring and compared the leak rate that they found to the previous leak rates determined by Dow s fugitive emission monitoring contractor. If EPA s leak rate was 3x what the contractor had reported for any fugitive component type, ELP was imposed for all fugitive component types at that plant, including monitoring open-ended lines at the closure device. Key point for valves: under MACT, if a valve leaks, you repair it and you re done. Under ELP, you must replace or repack the valve. The new packing or new valve must be low-emitting if commercially available. Even if you successfully repaired the leak, you still must replace or repack the valve.

6 ELP INFORMATION According to the EPA (at the ISA 2012 LDAR Symposium) ~95% of oil companies have ELPs, and 12 chemical companies At least 4 more have been issued to the oil and chemical industry since then, see the EPA Website for more information The reduction of LDAR non-compliance is listed in the EPA s Selection of National Enforcement Initiatives for FY

7 ELP DEFINITIONS Low Emission Valves (i) A valve (including its specific packing assembly) for which the manufacturer has issued a written warranty that it will not emit fugitives at greater than 100 ppm, and that, if it does so emit at any time in the first five years, the manufacturer will replace the valve; provided however, that no valve shall qualify as Low-E by reason of written warranty unless the valve (including its specific packing assembly) either: (a) first was tested by the manufacturer or a qualified testing firm pursuant to generally-accepted good engineering practices for testing fugitive emissions and the results of the testing reasonably support the warranty; or (b) is as an Extension of another valve that qualified as Low-E OR

8 ELP DEFINITIONS Low Emission Valves (ii) A valve (including its specific packing assembly) that: (a) Has been tested by the manufacturer or a qualified testing firm pursuant to generally-accepted good engineering practices for testing fugitive emissions and that, during the test, at no time leaked at greater than 500 ppm, and on Average, leaked at less than 100 ppm; or (b) Is an Extension of another valve that qualified as Low-E

9 Extension, shall mean that: ELP DEFINITIONS Extension (i) (ii) the tested and untested valves were produced by the same manufacturer to the same or essentially equivalent quality requirements; the characteristics of the valve that affect sealing performance (e.g., type of valve, stem motion, tolerances, surface finishes, loading arrangement, and stem and body seal material, design, and construction) are the same or essentially equivalent as between the tested valve and the untested valve; and (iii) the temperature and pressure ratings of the tested valve are at least as high as the temperature and pressure ratings of the untested valve.

10 ELP DEFINITIONS Low Emission Packing Low-Emissions Packing or Low-E Packing shall mean either (i) or (ii) as follows: (i) A valve packing product, independent of any specific valve, for which the manufacturer has issued a written warranty that the packing will not emit fugitives at greater than 100 ppm, and that, if it does so emit at any time in the first five years, the manufacturer will replace the product; provided however, that no packing product shall qualify as Low-E by reason of written warranty unless the packing first was tested by the manufacturer or a qualified testing firm pursuant to generally-accepted good engineering practices for testing fugitive emissions and the results of the testing reasonably support the warranty; OR

11 ELP DEFINITIONS Low Emission Packing (ii) A valve packing product, independent of any specific valve, that has been tested by the manufacturer or a qualified testing firm pursuant to generally-accepted good engineering practices for testing fugitive emissions, and that, during the test, at no time leaked at greater than 500 ppm, and on Average, leaked at less than 100 ppm.

12 ELP DEFINITIONS NOTE: Generally-accepted good engineering practices includes whether there is confidence that the test results will meaningfully predict valve performance in the field. This could include the number of mechanical cycles, the inclusion of thermal cycles, the pressure and temperature conditions, etc. If the valve must be repeatedly adjusted to pass the test, it decreases confidence.

13 The Search for Low-E Dow requested and reviewed testing data Valves Approved Dow Valve Manufacturers Packing Three manufacturers

14 AVAILABILITY CHALLENGES Many of the valves did not meet the Low-E definition per the ELP Either no warranty offered, or the warranty did not meet requirements of the ELP VALVES ELP requires test data to back low emission designation some results were too high, e.g. over 500 ppmv max Testing measured leak rate (e.g. mass/ time) instead of volumetric concentration, e.g. ppmv

15 AVAILABILITY CHALLENGES No scientific basis for correlating the test results between leak rate and volumetric concentration? DOW RESTRICTED

16 AVAILABILITY CHALLENGES Low emission packing is commercially available for certain applications, but not all U.S. based testing tends to be for packing in rising stem glands, per API 622, which excludes PTFE PACKING Some chemical services can utilize PTFE packing - lower maximum temperature services than the oil industry No standard or commonly used PTFE testing method

17 AVAILABILITY CHALLENGES Packing tests were based on a certain number of rings, for example 5. Does not qualify for packing glands if at least 5 rings do not fit Greater use of quarter turn valves in the chemical industry, which can have a smaller packing gland, limiting the number of packing rings PACKING Some testing used a live loaded design which may not be available for a valve that is being repacked Packing must be compatible with process, and possibly meet FDA, Kosher, Halal, etc.

18 AVAILABILITY CHALLENGES: SUMMARY No common standard for testing different types of valves Dominant packing test standard is API 622, for high temperature services, rising stem style gland No warranty that meets ELP offered for valves A wide variety of valve styles and configurations that affect stem sealing. Number of permutations is extremely large, hard to test for all conditions

19 AVAILABILITY CHALLENGES: SUMMARY ELP has commercially unavailable provisions Dow can use non-qualified low emission products if these provisions are met It requires contacting no less than three manufacturers of packing or valve type Commercially unavailable products require extra documentation/reporting and is rechecked annually

20 LOW EMISSION VALVE AND PACKING What would improve availability? Multi-Generational Plan Current Position Compliant Low emission testing data Common Testing Standards Wider acceptance by industry and governments Generation 3 Ideal Final Results Gate valves Packing Generation 2 Generation 1 Time Gen 0

21 LOW EMISSION VALVE AND PACKING Improving Availability- Ideal Final Results Globally accepted valve test standard Testing standard or standards that allow for multiple packing materials (graphite, PTFE, etc.) Reasonable extension of testing results (to other sizes, pressure classes, packing designs) Broader warranties that meet requirements of ELP agreements Government organizations that accept both leak rate and concentration data Continuous increase in types of valves that meet Low-E definitions

22 POSSIBLE IMPLICATIONS (SPECULATIVE) FOR THE VALVE INDUSTRY U.S. EPA considering inclusion of low emission regulations into Uniform Standards, and issuing more ELPs New chemical industry ELPs tend to be more restrictive on valve stem fugitive emissions than existing Oil Industry ELPs, therefore demand for Low-E products could increase Valve manufacturers that do not meet low emission definitions might lose market share

23 The Dow Chemical Company Questions? Thanks!! Dan DeVine