2016 VMA Technical Seminar Fugitive emission testing and certification of valves What we will have to do next? David Bayreuther March 10, 2016

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1 2016 VMA Technical Seminar Fugitive emission testing and certification of valves What we will have to do next? David Bayreuther March 10, 2016

2 Outline Sources of emissions History of legislation Review of standards Inconsistency in standards What is next? 2

3 Sources of fugitive emissions Refineries and chemical plants Primary types of sources: - equipment leaks - process venting - evaporation losses - flaring - accidents and equipment failures Methane (CH 4 ) - predominant greenhouse gas emitted by the oil and gas sector - more than 20x the global warming potential of carbon dioxide - detrimental to public health EPA reports 11% decrease since but will increase by 2030 if no action taken 3

4 History of legislation Fugitive emissions Air pollution control act 1955 Clean air act 1963 CAA amended in 1970 CAA amended in 1990 to include LDAR Late 1990s, under-reporting facilities assign dedicated management Late 2000s, consent decrees revised to require low leak packing technology Focus is on plants to monitor and repair Plants look to SDOs for help 4

5 Numerous emission test standards are written Fugitive emission test standards ANSI / ISA S ANSI / FCI 91-1 TA-Luft VDI 2440 ISO and -2 Shell SPE 77/300 Shell SPE 77/312 ChevronTexaco API-622 API-624 API-641 (pending) And more to follow isn t this too much already.why? 5 Metso Date Author Title

6 Confusion in the standards committees How do we prove performance through testing? Different tests for various valve types Emphasis on accuracy of the test What is an appropriate test method - Measurement method(s) - Helium vs. Methane - Units of measure - Test temperature - Temperature range - Number of thermal cycles - Test pressure - Packing adjustment allowed? - Static vs. dynamic leakage Lets review some of these issues in more detail 6

7 Which measurement method? Global versus local method Global methods - Vacuum - Bagging - Flushing Local method - Sniffing 7

8 Testing with Helium or Methane? Safety and other considerations Methane - Limited laboratories - Non-toxic but extremely flamable - Explosive when mixed with air - AIT limits maximum test temperature Helium - All laboratories - Readily available - Not flamable - No limit to maximum test temperature 8

9 Units of measure Can you correlate to actual in-service results? Methane - Units are ppmv Helium - Volumetric flow units are mbar-l/s per mm of stem diameter - Ranges from 1,78x10-7 to 1,78x10-4 or - Mass flow units are mg/s per meter of stem diameter - Ranges from 10-5 to 10-2 Not possible to correlate Helium to Methane. or mbar-l/s-mm to ppmv 9

10 Test temperature Is it acceptable if the packing does not reach the test temperature? Goal is to verify that the seal design will remain tight through entire valve temperature rating Typically, the internal fluid establishes the operating temp., and the packing and seals are closer to ambient Using local heat sources the packing box does not reach the full test temp. Test in an oven and the entire valve achieves the test temp. ISO versus API 10

11 Test temperature range What is ambient temperature? ISO Can require 2 tests to cover the temperature range Test at room temp qualifies valve from -29C to +40C Problem example with ISO

12 Number of thermal cycles How many are necessary? Thermal cycles establish time needed to complete test Reason for a thermal cycle Min. per ISO is 2 cycles Some standards require up to 5 Examples of test results 12

13 Test pressure What is the appropriate value? Valve rating at the test temperature? API standards use 600 psig or the valve body rating, whichever is less Challenges in achieving full valve rating 13

14 Is packing adjustment during test allowed? The opinions vary Yes - it simulates the real operating environment Yes but only once after the 1st thermal cycle No - it indicates a problem with the valve design ISO allows one adjustment per stage of testing API allows none 14

15 Despite all the work, test results are not definitive Other factors to consider One successful test in a laboratory is no guarantee of future results Success in a laboratory does not equal success in the plants Factors not address in laboratory test: - thermal stress - pipe stress - flow erosion - vibration - effects of corrosion (both within the system and from outside conditions) - mechanical wear - aging - environment 15

16 Summary on testing Emissions testing standards are a confusing mess... Comparison between different standards is nearly impossible Standards do not take into account the process conditions The number of tests within the standards is practically unlimited - For a valve manufacturer it is impossible to have all the combinations covered But we have excellent results Significant improvements to packing and seal materials, and installation techniques, leading to lower fugitive emissions 16

17 What does the future bring? More change... Latest legislation changes - Announced strategy to reduce Methane emission in In 2015, announced new goal to cut Methane emissions from oil & gas sector by 40 45% by 2025 EPA is seeking expert input on how to update and modernize the LDAR program API developing a new standard for rotary valves 17 Metso Date Author Title

18 Thank you for your time and attention