VAM utilisation - Versionsgeschichte

Helm: /* Flow-reversal oxidation - operating principals */

2012-05-08T13:22:18Z

‎Flow-reversal oxidation - operating principals

Helm: /* Flow-reversal oxidation - operating principals */

2012-05-08T13:19:51Z

‎Flow-reversal oxidation - operating principals

Helm: /* Flow-reversal oxidation - operating principals */

2012-05-08T13:16:51Z

‎Flow-reversal oxidation - operating principals

Helm: /* Flow-reversal oxidation - operating principals */

2012-05-08T13:16:29Z

‎Flow-reversal oxidation - operating principals

Helm: /* Flow-reversal oxidation - operating principals */

2012-05-08T13:15:57Z

‎Flow-reversal oxidation - operating principals

Helm: /* Flow-reversal oxidation - operating principals */

2012-05-08T13:14:17Z

‎Flow-reversal oxidation - operating principals

Helm: /* Flow-reversal oxidation - operating principals */

2012-05-08T13:10:53Z

‎Flow-reversal oxidation - operating principals

Helm: /* Flow-reversal oxidation - operating principals */

2012-05-08T12:52:45Z

‎Flow-reversal oxidation - operating principals

Helm: /* Flow-reversal oxidation - operating principals */

2012-05-08T12:49:18Z

‎Flow-reversal oxidation - operating principals

Helm: /* Flow-reversal oxidation - operating principals */

2012-05-08T12:48:18Z

‎Flow-reversal oxidation - operating principals

@@ Zeile 17: / Zeile 17: @@
 All operating VAM projects to utilise CMM are in a research or a demonstration phase. At the moment two companies are notably active in developing VAM technologies. Moreover a third company is developing a VAM utilisation, but has not demonstrated its technology yet.
-For more information see the description of these technologies from the respective companies:
+For more information see the description of these technologies from companies' papers:
 . [http://www.megtec.com Vocsidizer]<br /> [[Datei:Vocsidizer.pdf|thumb]]

← Nächstältere Version		Version vom 8. Mai 2012, 13:19 Uhr
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	1. [http://www.megtec.com Vocsidizer]<br /> [[Datei:Vocsidizer.pdf\|thumb]]		1. [http://www.megtec.com Vocsidizer]<br /> [[Datei:Vocsidizer.pdf\|thumb]]

−	2. [http://~~ausruestung~~.~~atec~~.~~de/englisch/bhkw_pics_eng.htm ATEC “Technical equipment for coal mine suction and utilisation, Combined power and heat systems”~~]<br />	+	2. [http://www.biothermica.com Vamox]<br />
		+	[[Datei:Vamox.pdf\|thumb]]
		+
		+	3. Vamcat [[Datei:Vamcat.pdf\|thumb]]

@@ Zeile 19: / Zeile 19: @@
 For more information see the description of these technologies from the respective companies:
-. [http://www.megtec.com "Vocsidizer"]<br />
+. [http://www.megtec.com Vocsidizer]<br /> [[Datei:Vocsidizer.pdf|thumb]]
 . [http://ausruestung.atec.de/englisch/bhkw_pics_eng.htm ATEC “Technical equipment for coal mine suction and utilisation, Combined power and heat systems”]<br />

@@ Zeile 18: / Zeile 18: @@
 For more information see the description of these technologies from the respective companies:
 . [http://www.megtec.com "Vocsidizer"]<br />
 [[Datei:Vocsidizer.pdf|thumb]]
 . [http://ausruestung.atec.de/englisch/bhkw_pics_eng.htm ATEC “Technical equipment for coal mine suction and utilisation, Combined power and heat systems”]<br />

← Nächstältere Version		Version vom 8. Mai 2012, 13:15 Uhr
Zeile 18:		Zeile 18:

	For more information see the description of these technologies from the respective companies:		For more information see the description of these technologies from the respective companies:
−	~~::Vocsidizer~~ [http://www.megtec.com][[Datei:Vocsidizer.pdf\|thumb]]	+	1. [http://www.megtec.com "Vocsidizer"]<br />
		+	[[Datei:Vocsidizer.pdf\|thumb]]
		+	2. [http://ausruestung.atec.de/englisch/bhkw_pics_eng.htm ATEC “Technical equipment for coal mine suction and utilisation, Combined power and heat systems”]<br />

← Nächstältere Version		Version vom 8. Mai 2012, 13:14 Uhr
Zeile 18:		Zeile 18:

	For more information see the description of these technologies from the respective companies:		For more information see the description of these technologies from the respective companies:
−	::Vocsidizer	+	::Vocsidizer [http://www.megtec.com][[Datei:Vocsidizer.pdf\|thumb]]

@@ Zeile 16: / Zeile 16: @@
 The VAM from the ventilation shaft has to be compressed to compensate the pressure losses in the air – methane – mixture filtration and oxidation area. This additional pressure can’t be produced from the ventilation fan.
 All operating VAM projects to utilise CMM are in a research or a demonstration phase. At the moment two companies are notably active in developing VAM technologies. Moreover a third company is developing a VAM utilisation, but has not demonstrated its technology yet.
-For more information on see:
-::
+For more information see the description of these technologies from the respective companies:

@@ Zeile 15: / Zeile 15: @@
 However, there are a few drawbacks that show the inefficiency of the oxidizing process. In the first place it is the decrease in pressure during the VAM flow through the oxidizing chamber.  There is also a lot of dirt in the flow of the VAM that causes contamination of the filling material and the valves. Another problem is the fluctuating heat dispersion. The dispersion effuses in a parabolic profile. So, in the middle of the chamber it is warmer than in the peripherals.
 The VAM from the ventilation shaft has to be compressed to compensate the pressure losses in the air – methane – mixture filtration and oxidation area. This additional pressure can’t be produced from the ventilation fan.
-All operating VAM projects to utilise CMM are in a research or a demonstration phase. At the moment two companies are notably active in developing VAM technologies. Moreover a third company is developing a VAM utilisation, but has not demonstrated its technology yet. Nearly all information comes from these companies. So in the following we will describe this technology by using companies’ papers.
+All operating VAM projects to utilise CMM are in a research or a demonstration phase. At the moment two companies are notably active in developing VAM technologies. Moreover a third company is developing a VAM utilisation, but has not demonstrated its technology yet.

@@ Zeile 9: / Zeile 9: @@
 ===Flow-reversal oxidation - operating principals ===
-[[Bild:Flow_reversal_oxidation.jpg|thumb|Text der Bildbeschreibung]]The basic operating principal underlying flow-reversal regenerative oxidizers is rather straightforward. Each oxidizer unit comprises a bed of heat exchange material with a preheating system (e.g. electric heating element). Ducting conveys the gas to be oxidized (VAM in this case) into the oxidizer core. The heat exchange material typically comprises ceramic pellets with a high surface area-to-volume ratio. The oxidizer also has a system of valves and dampers that direct the VAM flow across the bed. To start up the system, the preheating system raises the temperature of the heat exchange material in the oxidizer bed to or above the auto-oxidation temperature of VAM (> 800°C), at which point the preheating system is turned off and VAM inflow is initiated. The methane oxidizes when it reaches the preheated bed, releasing the heat of combustion. This heat, in turn, is transferred to the bed, thereby maintaining its temperature at or above the temperature necessary to support auto-thermal operation. It should be noted that the oxidation process is flameless and, following the initial bed preheating, requires no auxiliary fuel so long as adequate inflow methane concentrations are maintained.
+[[Bild:Flow_reversal_oxidation.jpg|thumb|Flow-Reversal Oxidation]]The basic operating principal underlying flow-reversal regenerative oxidizers is rather straightforward. Each oxidizer unit comprises a bed of heat exchange material with a preheating system (e.g. electric heating element). Ducting conveys the gas to be oxidized (VAM in this case) into the oxidizer core. The heat exchange material typically comprises ceramic pellets with a high surface area-to-volume ratio. The oxidizer also has a system of valves and dampers that direct the VAM flow across the bed. To start up the system, the preheating system raises the temperature of the heat exchange material in the oxidizer bed to or above the auto-oxidation temperature of VAM (> 800°C), at which point the preheating system is turned off and VAM inflow is initiated. The methane oxidizes when it reaches the preheated bed, releasing the heat of combustion. This heat, in turn, is transferred to the bed, thereby maintaining its temperature at or above the temperature necessary to support auto-thermal operation. It should be noted that the oxidation process is flameless and, following the initial bed preheating, requires no auxiliary fuel so long as adequate inflow methane concentrations are maintained.
 If the inflow of ambient-temperature ventilation exhaust air is maintained in only one direction, the heated area of the bed would migrate across the bed in the direction of flow until the heat essentially is blown out of the bed. If that happens, bed temperatures would no longer be adequate to sustain auto-thermal operation, and the system would cease oxidizing subsequent VAM inflows. To preclude cooling of the bed, dampers and valves redirect the flow of incoming ventilation exhaust air from one side of the bed to the other, typically on a timeframe of every two or three minutes. This flow-reversal process, which is managed by a programmable logic controller, maintains the hot area of the bed in the middle of the oxidizer, where it is available to support oxidation of a constant stream of VAM over time.