GASEOUS TRACER LEAK DETECTION

1 . A method of detecting a leak in a system for coking coal, the method comprising:

discharging a gaseous tracer adjacent to a structure in the system for coking coal, wherein the structure at least partially divides a high-pressure system and a low-pressure system; and

after discharging the gaseous tracer, measuring an amount of the gaseous tracer at a location within and/or downstream from the low-pressure system,

wherein measuring a spike in the amount of gaseous tracer at the location within and/or downstream from the low-pressure system indicates there is a leak in the structure.

2 . The method of claim 1 , wherein the structure is configured to fluidly isolate the high-pressure system and the low-pressure system.

3 . The method of claim 1 , wherein discharging the gaseous tracer adjacent to the structure comprises discharging the gaseous tracer in the high-pressure system.

4 . The method of claim 1 , wherein the system for coking coal includes at least one oven and at least one sole flue chamber adjacent to the at least one oven, and wherein the at least one oven is the high pressure system, the at least one sole flue chamber is the low pressure system, and the structure divides the at least one oven and the at least one sole flue chamber.

5 . The method of claim 1 , the system for coking coal includes at least one oven, at least one sole flue chamber adjacent to the at least one oven, and at least one tunnel, and wherein the high pressure system is an environment external to the at least one oven, the at least one sole flue chamber, and/or the at least one tunnel, and wherein the low pressure system is the at least one oven, the at least one sole flue chamber, or the at least one tunnel.

6 . The method of claim 1 , wherein the system for coking coal is a heat recovery coke plant, a non-heat recovery coke plant, or a byproduct coke plant.

7 . The method of claim 1 , further comprising:

measuring a baseline amount of the gaseous tracer before discharging the gaseous tracer adjacent to the structure; and

comparing the baseline amount of the gaseous tracer with the gaseous tracer measured after discharging the gaseous tracer adjacent the structure to determine if there is a leak.

8 . The method of claim 7 , wherein measuring a baseline amount of gaseous tracer further comprises zeroing a reading on a measuring device.

9 . The method of claim 1 , wherein measuring the amount of gaseous tracer at the location comprises continuously measuring the amount of gaseous tracer for a period.

10 . The method of claim 1 , wherein the gaseous tracer mixes with other gases in the system for coking coal, and wherein the flow of the gaseous tracer and other gases is turbulent in at least one region of the system between the structure and the location.

11 . The method of claim 1 , wherein a Reynolds number defining the flow of the gaseous tracer is greater than 4,000 in at least one region of the system between the structure and the location.

12 . The method of claim 1 , wherein discharging the gaseous tracer adjacent to the structure comprises discharging the gaseous tracer within two inches of the structure.

13 . The method of claim 1 , wherein discharging the gaseous tracer adjacent to the structure comprises spraying the gaseous tracer across a first external facing surface of the system for coking coal.

14 . The method of claim 12 , wherein discharging the gaseous tracer comprises discharging a first amount of the gaseous tracer adjacent to the structure, the method further comprising discharging a second amount of the gaseous tracer adjacent to the structure if a leak is detected at the structure, wherein the second amount of the gaseous tracer is sprayed on a second external facing surface area of the system positioned within and smaller than the first external facing surface area.

15 . The method of claim 1 , wherein the gaseous tracer is a compound (a) that is not otherwise present or generally present in the system and (b) that is detectable at the location.

16 . The method of claim 1 , wherein the gaseous tracer is a noble gas.

17 . The method of claim 1 , wherein the gaseous tracer is helium.

18 . The method of claim 1 , wherein the structure includes insulation.

19 . The method of claim 1 , wherein the steps of injecting and measuring are performed without shutting off operation of the system for coking coal.

20 . The method of claim 1 , wherein a temperature of at least one of the high pressure or the low-pressure system is 1,000 degrees Celsius or higher during the steps of injecting and measuring.

21 . A method of detecting an air leak in a system for coking coal, the method comprising:

injecting a first known amount of gaseous tracer into the system at a first location, wherein the first location is adjacent to a known leak site or another site that allows air to enter into the system;

measuring a first test amount of the gaseous tracer at a location downstream of the first location;

generating a first volume versus time graph of the first test amount of the gaseous tracer;

discharging a second known amount of the gaseous tracer adjacent to a first potential leak site, wherein the second known amount is equal to the first known amount;

measuring a second test amount of the gaseous tracer at the location downstream of the first location, wherein the location downstream of the first location is also downstream of the first potential leak site;

generating a second volume versus time graph of the second test amount of the gaseous tracer; and

comparing the first and second graphs to determine (i) if there is a leak at the first potential leak site, and/or (ii) the size of the leak.

22 . The method of claim 21 , wherein:

the first volume versus time graph has a first slope, one or more first inflection points, and a first magnitude; and

the second volume versus time graph has a second slope, one or more second inflection points, and a second magnitude.

23 . The method of claim 22 , wherein the size of the leak is determined by comparing the first slope with the second slope and/or by comparing the first magnitude with the second magnitude.

24 . The method of claim 22 wherein the first magnitude corresponds to a first area under the curve and the second magnitude corresponds to a second area under the curve.

25 . The method of claim 22 , further comprising comparing the distance between the one or more first inflection points with the distance between the one or more second inflection points to determine whether there is one leak or multiple leaks.

26 . The method of claim 21 , wherein injecting the first amount of the gaseous tracer into the system and discharging the second amount of the gaseous tracer adjacent to a potential leak site comprises using a gaseous tracer spray probe, the probe including:

a regulator;

a known volume container carrying a known volume of the gaseous tracer; and

a valve configured to dispense a known volume of the gaseous tracer equal to the first and second known amounts of the gaseous tracer.

27 . The method of claim 21 , wherein the system comprises a plurality of coke ovens, a plurality of heat recovery steam generators, and a common tunnel fluidly coupled to the plurality of coke ovens and the plurality of heat recovery steam generators.

28 . A method of detecting an air leak in a system for coking coal, the method comprising:

measuring a baseline amount of a gaseous tracer at a first location;

injecting a first amount of the gaseous tracer into the system at a second location upstream of the first location, wherein the second location is adjacent to a known leak site or another site that allows air to enter into the system;

determining a residence time for the first amount of the gaseous tracer to travel from the second location to the first location;

discharging a second amount of the gaseous tracer adjacent to a first potential leak site upstream from the first location;

measuring an amount of the gaseous tracer at the first location beginning when the gaseous tracer is discharged at the first potential leak site for a first period approximately equal to or longer than the residence time;

comparing the baseline amount of the gaseous tracer with the amount of the gaseous tracer measured during the first period to determine if there is a leak at the first potential leak site.

29 . The method of claim 28 , further comprising:

discharging a third amount of the gaseous tracer adjacent to a second potential leak site;

measuring an amount of the gaseous tracer at the first location beginning when the gaseous tracer is discharged at the second potential leak site and lasting for a second period approximately equal to or longer than the residence time; and

comparing the baseline amount of the gaseous tracer with the amount of the gaseous tracer observed during the second period to determine if there is a leak at the second potential leak site.

30 . The method of claim 29 , wherein the first amount of the gaseous tracer, the second amount of the gaseous tracer, and the third amount of the gaseous tracer are equal.

31 . The method of claim 30 , further comprising, when there is a first leak at the first potential leak site and a second leak at the second potential leak, comparing the amount of the gaseous tracer measured during the first period and the second period to determine whether the first leak or second leak is larger.

32 . The method of claim 30 , further comprising, when there is a first leak at the first potential leak site and a second leak at the second potential leak site, determining which leak to repair first by comparing the amount of the gaseous tracer measured during the first period and the amount of the gaseous tracer measured during the second period.

33 . The method of claim 30 , wherein comparing the amount of the gaseous tracer measured during the first and second periods comprises:

generating a first amount versus time graph of the gaseous tracer during the first period and a second amount versus time graph of the gaseous tracer during the second period, wherein:

the first amount is a first volume or a first mass,

the second amount is a second volume or a second mass,

the first amount versus time graph has a first area under the curve, and

the second amount versus time graph has a second area under the curve; and

comparing the first area under the curve and the second area under the curve.

34 . The method of claim 33 , wherein the first amount versus time graph further comprises a first shape, and wherein the second amount versus time graph further comprises a second shape, and wherein comparing the amount of the gaseous tracer further comprises comparing the first shape and the second shape.

35 . The method of claim 28 , wherein the residence time is 120 seconds or less.

36 . The method of claim 28 , wherein the system comprises a plurality of coke ovens, a sole flue chamber, a plurality of air ducts fluidly connecting the sole flue chamber and the plurality of coke ovens, a plurality of heat recovery steam generators, a common tunnel, and/or a plurality of uptake ducts fluidly coupling the plurality of coke ovens and/or the plurality of heat recovery steam generators.

37 . A method of detecting an air leak in a system for coking coal under a negative pressure, the method comprising:

spraying an external facing region of a system for coking coal with a gaseous tracer;

measuring an amount of the gaseous tracer in the system for coking coal at a location downstream from the first external facing region, wherein a spike in the amount of the gaseous tracer measured indicates there is one or more leaks in the external facing region;

discharging a device configured to dispense smoke or colored gas adjacent to the external facing region of the system; and

observing the discharged smoke or colored gas to detect a sub-region of the external facing region having the one or more leaks.

38 . The method of claim 37 , wherein the device is a smoke generator or a smoke bomb.

39 . A method of detecting an air leak between a high-pressure system and a low-pressure system, wherein the high-pressure system and the low-pressure system are designed to be fluidly isolated, the method comprising:

injecting a gaseous tracer into the high-pressure system at a first location adjacent the low-pressure system; and

measuring a concentration of the gaseous tracer at a second location after injecting the gaseous tracer into the high-pressure system, wherein the second location is inside the low-pressure system;

wherein detecting the gaseous tracer in the low-pressure system after injecting the gaseous tracer into the high-pressure system indicates there is a leak between the high-pressure system and the low-pressure system.

40 . The method of claim 39 wherein the low-pressure system is a heat recovery coke plant and the high-pressure system is an external environment surrounding the heat recovery coke plant.

41 . The method of claim 39 wherein the high-pressure system and/or the low-pressure system is a region within a by-product coke plant.

42 . The method of claim 39 , further comprising:

measuring a baseline concentration of the gaseous tracer in the low-pressure system before discharging the gaseous tracer into the high-pressure system; and

comparing the baseline concentration of the gaseous tracer with a test concentration of the gaseous tracer measured in the low-pressure system after discharging the gaseous tracer into the high-pressure system to determine if there is a leak at the potential leak site.

43 . The method of claim 39 , further comprising:

generating a volume versus time graph of a concentration of the measured gaseous tracer; and

at least semi-quantitatively determining a size of the leak.

44 . The method of claim 39 , wherein at least one of the high-pressure system and the low-pressure system is a region within a coke plant, and wherein the steps of injecting and measuring are performed without shutting off operation of the coke plant.

45 . A method of detecting an air leak between a high-pressure system and a low-pressure system, the method comprising:

injecting a gaseous tracer into the high-pressure system at a first location adjacent to the low-pressure system; and

measuring the concentration of the gaseous tracer at a second location, wherein the second location is in the low-pressure system;

wherein detecting a first spike and a subsequent second spike temporally spaced apart from the first spike in the concentration of the gaseous tracer in the low-pressure system indicates there is a leak between the high-pressure system and the low-pressure system.

46 . The method of claim 45 , wherein the high-pressure system and/or the low-pressure system is a region within a byproduct coke plant.

47 . The method of claim 45 wherein the high-pressure system is a first region within a byproduct coke plant and the low-pressure system is a second region within the byproduct coke plant.

48 . The method of claim 45 , wherein at least one of the high-pressure system and the low-pressure system is a region within a coke plant, and wherein the steps of injecting and measuring are performed without shutting off operation of the coke plant.