contros hydroc methane sensor at mc118 presented by ken sleeper seabed technology research center...
TRANSCRIPT
1
Contros HydroCMethane Sensor
at MC118
Presented by Ken SleeperSeabed Technology Research Center
Mississippi Mineral Resources InstituteUniversity of Mississippi
October 26, 2010
2
Why Contros
• Need for a direct measure of methane on the seafloor
– PFA, BBLA, CSA and future arrays
– Raman Spectrometer, METS sensor, Mid-IR and Mass Spectrometer
– Evaluate new near-IR detector• Chris Martens’ METS shoot out – Survey Mode• Rich Camilli redesign of the power draw –
Observatory Mode
3
Contros near IR CH4 sensor
Key Features
• Membrane Diffusion• Partial Pressures (Henry’s Law)• IR absorption bands of Methane• Concentration• Pressure• Temperature• Relative Humidity
4
June 2010 MC118 Cruise
• 15 CTD CASTS with CDOM and Transmissometer
• 5 Casts with the Contros– 3 with pump cowling– 1 with no pump cowling– 1 with pump operational– 3 with bottles & GC work
• 4 separate Mass Spec casts
5
CTD Cast 13With CDOM & O2
6
9:58:39 10:03:5910:09:1810:14:3810:19:5810:25:1810:30:380
0.5
1
1.5
2
2.5
3
3.5
4
62310 Cast 11Concentration µmol/L
Concentration µmol/L
10:49:4810:55:0811:00:2811:05:4811:11:0811:16:2811:21:4811:27:0811:32:280
0.5
1
1.5
2
2.5
3
62310 Cast 12Concentration µmol/L
Concentration µmol/L
7
13:15:08 13:17:48 13:20:28 13:23:08 13:25:48 13:28:28 13:31:08 13:33:48 13:36:28 13:39:08 13:41:48 13:44:28 13:47:08 13:49:48 13:52:28 13:55:080
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
062410 cast 13Concentration µmol/L
Concentration µmol/L
8
13:15:0813:19:2313:23:3813:27:5313:32:0813:36:2313:40:3813:44:5313:49:0813:53:23900
950
1000
1050
1100
1150Pressure
TIME (hr:min:sec)
Pres
sure
(mba
r)
13:12:00 13:19:12 13:26:24 13:33:36 13:40:48 13:48:00 13:55:12 14:02:2425
27
29
31
33
35
37
39
41
Gas Temperature (°C)
CH4-0510-006 CH4-0510-006 T_gas °C
Tem
pera
ture
Time (hr:min:sec)
13:12:00 13:19:12 13:26:24 13:33:36 13:40:48 13:48:00 13:55:12 14:02:240
10
20
30
40
50
60
70Relative Humidity (rh%_gas%)
CH4-0510-006 CH4-0510-006 %rH_gas %
Rela
tive
Hum
idity
(%)
Time (hr:min:sec)13:15:0813:19:0313:22:5813:26:5313:30:4813:34:4313:38:3813:42:3313:46:2813:50:2313:54:18
00.20.40.60.8
11.21.41.61.8
2
062410 cast 13Concentration µmol/L
Concentration µmol/L
Time (hr:min:sec)
Conc
entr
ation
13:15:0813:19:2313:23:3813:27:5313:32:0813:36:2313:40:3813:44:5313:49:0813:53:2339.2
39.4
39.6
39.8
40
40.2
40.4
40.6
40.8
41Control Temperature (°C)
Time (hr:min:sec)
Tem
pera
ture
(°C)
Detection Chamber Readings• Control Temperature• Gas Temperature• Pressure• Relative Humidity• Raw electrical signal
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CAST 13 Raw Voltage Output
10
Depth Profile – Cast 13IR raw output
Down Cast UP Cast
Depth ProfilesMass Spec Casts
11
Cast 1 Cast 2 Cast 3
12
Future Directions
• AUV Surveys– Mid-Atlantic Ridge
• Geochemical Array - BBLA– Duty cycle vs reconfigure
power draw– Post deployment follow
up
• Sensor development– Shorten response time– Lower detection levels
13
Funding for this project is generously provided by
NOAA/OER, NIUSTDOI/BOEMRE (MMS)
andDOE/NETL
Special thanks to Andy Gossett, Matt Lowe, Brian Noakes, Larry Overstreet and the crew of the Pelican for handling the at-sea operations
of the equipment