103. Carbon Monoxide Emissions and Exposures on Recreational Boats Under Various Operating Conditions

2003 ◽  
Author(s):  
G. Earnest ◽  
A. Echt ◽  
J. McCammon ◽  
K. Dunn ◽  
R. McCleery ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Operating Conditions

Moving Brick Receiver–Reactor: A Solar Thermochemical Reactor and Process Design With a Solid–Solid Heat Exchanger and On-Demand Production of Hydrogen and/or Carbon Monoxide

2019 ◽  
Vol 141 (2) ◽  
Author(s):  
Silvan Siegrist ◽  
Henrik von Storch ◽  
Martin Roeb ◽  
Christian Sattler
Keyword(s):  
Carbon Monoxide ◽  
Heat Exchanger ◽  
Solid Phase ◽  
Chemical Conversion ◽  
Operating Conditions ◽  
On Demand ◽  
Commercial Plant ◽  
Production Of Hydrogen ◽  
Solar Thermochemical ◽  
Oxidation Reactor

Three crucial aspects still to be overcome to achieve commercial competitiveness of the solar thermochemical production of hydrogen and carbon monoxide are recuperating the heat from the solid phase, achieving continuous or on-demand production beyond the hours of sunshine, and scaling to commercial plant sizes. To tackle all three aspects, we propose a moving brick receiver–reactor (MBR2) design with a solid–solid heat exchanger. The MBR2 consists of porous bricks that are reversibly mounted on a high temperature transport mechanism, a receiver–reactor where the bricks are reduced by passing through the concentrated solar radiation, a solid–solid heat exchanger under partial vacuum in which the reduced bricks transfer heat to the oxidized bricks, a first storage for the reduced bricks, an oxidation reactor, and a second storage for the oxidized bricks. The bricks may be made of any nonvolatile redox material suitable for a thermochemical two-step (TS) water splitting (WS) or carbon dioxide splitting (CDS) cycle. A first thermodynamic analysis shows that the MBR2 may be able to achieve solar-to-chemical conversion efficiencies of approximately 0.25. Additionally, we identify the desired operating conditions and show that the heat exchanger efficiency has to be higher than the fraction of recombination in order to increase the conversion efficiency.

Carbon Filament Growth on Fully Formulated Pd/Rh Automotive Catalysts

2000 ◽  
Vol 6 (S2) ◽  
pp. 66-67
Author(s):  
J.W. Hangas ◽  
G.W. Graham ◽  
R.W. McCabe ◽  
W. Chun
Keyword(s):  
Carbon Monoxide ◽  
Catalytic Activity ◽  
Operating Conditions ◽  
The Other ◽  
Carbon Filament ◽  
Automotive Catalysts ◽  
Exhaust Catalysts ◽  
Stabilization Procedure ◽  
Carbon Filaments ◽  
Aged Catalyst

Automotive exhaust catalysts are typically operated under stoichiometric conditions to minimize nitrogen oxide, hydrocarbon, and carbon monoxide pollutants. These catalysts do not form carbon filaments under normal operating conditions. In development of catalysts, however, a stabilization procedure is sometimes utilized on used catalysts (dynamometer or vehicle) to purge the catalyst of sulfur prior to measuring the catalytic activity in sweep and light-off testing. The stabilization procedure consists of running the catalyst under rich (excess fuel) conditions for 0.5hr. This study documents the existence of carbon filaments due to the stabilization procedure and discusses the effect of filaments on subsequent testing.Two separate catalysts were used in this study. The first was a 50,000 mile vehicle aged catalyst that had also been through the stabilization procedure and then sweep and light-off tested. The other was only dynamometer aged for 120hr at 850°C (1560°F).

Does the Burning of Moxa (Artemisia vulgaris) in traditional Chinese medicine constitute a health hazard?

2009 ◽  
Vol 27 (1) ◽  
pp. 16-20 ◽  
Author(s):  
John Wheeler ◽  
Belinda Coppock ◽  
Cecil Chen
Keyword(s):  
Carbon Monoxide ◽  
Chinese Medicine ◽  
Traditional Chinese Medicine ◽  
Health Hazard ◽  
Urban Environments ◽  
Operating Conditions ◽  
Therapeutic Modality ◽  
Worst Case ◽  
Safety Standards ◽  
Exposure Levels

Background Concerns have been expressed about potential toxicity of the smoke produced by the burning of moxa in traditional Chinese medicine. With the advent of strict anti-smoking legislation in the UK, it was decided to test the volatiles produced by moxibustion and compare them with current agreed safe exposure levels. Method Moxa, in the form of cigar shaped moxa “sticks” or “rolls”, was tested under International Organization for Standardization conditions in a tobacco testing laboratory, and the quantities of a number of pre-determined volatiles measured. The smoke tested was “sidestream smoke”, the smoke which arises from the burning tip of the moxa. The test results were then scaled up to reflect normal use and to provide direct comparisons with agreed national safety standards for both short- and long-term exposure levels. Results Levels of only two volatiles produced were equivalent or greater than the safe exposure levels, as was the carbon monoxide level reported, both as a consequence of using worst case assumptions for comparison. Under normal operating conditions neither volatile nor carbon monoxide would present a safety hazard. One group of chemicals tested, the aromatic amines, with known carcinogenic properties have no agreed safety levels. Results for these in the study compared favourably with background levels reported in urban environments. Conclusion There are no immediate concerns arising from the continued use of moxa as a therapeutic modality in traditional Chinese medicine. Further testing may be required to establish whether current recommendations for ventilation and cleansing of treatment room surfaces may need to be revised. Stronger recommendations may also be necessary on the inadvisability of using moxa on broken skin.

Thermodynamic Investigation of Acetic Acid Steam Reforming for Hydrogen Production

2012 ◽  
Vol 550-553 ◽  
pp. 2801-2804
Author(s):  
Peng Fu ◽  
Sen Meng An ◽  
Wei Ming Yi ◽  
Xue Yuan Bai
Keyword(s):  
Carbon Monoxide ◽  
Acetic Acid ◽  
Hydrogen Production ◽  
Steam Reforming ◽  
Operating Conditions ◽  
Negative Effects ◽  
Minimization Method ◽  
Gibbs Free Energy Minimization ◽  
Methane Selectivity ◽  
Increasing Temperature

The thermodynamics of acetic acid steam reforming (AASR) for hydrogen production were simulated using a Gibbs free energy minimization method to study the influences of pressure, temperature and water to acetic acid molar feed ratios (WAFR) on the AASR. On the basis of the equilibrium calculations, the optimal operating conditions obtained were 700-800 oC, 1bar and WAFR = 6-10. At these conditions, the yield and selectivity of hydrogen were maximized and the formation of methane and coke was almost inhibited. Higher pressures had negative effects on the yields and selectivities of hydrogen and carbon monoxide. With increasing temperature from 300 to 1000 oC, the selectivity for hydrogen and carbon monoxide increased significantly along with a reduction in methane selectivity. Increase in the WAFR led to the increase in hydrogen selectivity and the decrease in carbon monoxide selectivity.

Effect of Trace Contaminants on PEM Fuel Cell Performance

2005 ◽  
Vol 885 ◽  
Author(s):  
Tony Thampan ◽  
Rick Rocheleau ◽  
Keith Bethune ◽  
Douglas Wheeler
Keyword(s):  
Carbon Monoxide ◽  
Fuel Cell ◽  
Strong Dependence ◽  
Pem Fuel Cells ◽  
Gas Analysis ◽  
Operating Conditions ◽  
Test Facility ◽  
Systematic Evaluation ◽  
Fuel Cell Performance ◽  
The Impact

ABSTRACTAt the Hawaii Fuel Cell Test Facility a systematic evaluation of the impact of impurities in hydrogen is underway to evaluate the effects on the performance of PEM fuel cells. Initial tests are being conducted using carbon monoxide and hydrocarbon contaminants. The effects of carbon monoxide poisons at atmospheric and pressurized operating conditions have shown a strong dependence on concentration of the impurity over the range 6.7 µmole/mole to 29.3 µmole/mole. Additionally, benzene and toluene were tested at 20 µmole/mole. Although both benzene and toluene showed no evidence of fuel cell degradation, on-line gas analysis of the exit anode stream showed that toluene hydrogenation occurs in the anode resulting in 90% conversion of the toluene to methyl-cyclohexane.

scholarly journals An Analytical Study of Nitrogen Oxides and Carbon Monoxide Emissions in Hydrocarbon Combustion With Added Nitrogen: Preliminary Results

1980 ◽  
Author(s):  
D. A. Bittker
Keyword(s):  
Carbon Monoxide ◽  
Nitrogen Oxides ◽  
Analytical Study ◽  
Primary Objective ◽  
Operating Conditions ◽  
Department Of Energy ◽  
Critical Research ◽  
Preliminary Results ◽  
Hydrocarbon Combustion

This work is one part of a four-part Critical Research and Technology Fuels Combustion Program funded by the Department of Energy. The primary objective of this part of the program is to analytically determine the effect of combustor operating conditions on the conversion of fuel-bound nitrogen (FBN) to nitrogen oxides (NOx). The effect of FBN and of operating conditions on carbon monoxide (CO) formation was also studied.

scholarly journals Optimization of Working Conditions for Perovskite-Based Gas Sensor Devices by Multiregression Analysis

2019 ◽  
Vol 2019 ◽  
pp. 1-19 ◽  
Author(s):  
Fabio Zaza ◽  
Vanessa Pallozzi ◽  
Emanuele Serra
Keyword(s):  
Carbon Monoxide ◽  
Mathematical Models ◽  
Gas Sensor ◽  
Flow Rate ◽  
Gas Flow ◽  
Resource Depletion ◽  
Productive Efficiency ◽  
Operating Conditions ◽  
Gas Flow Rate ◽  
Sensor Devices

Environmental degradation and resource depletion drive scientific research priorities to develop technologies for sustainable productive systems. Among them, chemical sensing technology plays a key role for regulating energetic, ecological, and productive efficiency by monitoring and controlling the industrial processes. Semiconducting metal oxide sensors are particularly attractive technology because of their simplicity in function, small size, and projected low cost. The aim of this work is to synthesize Ti-substituted lanthanum ferrite perovskite, LaFe0.8Ti0.2O3, in order to develop a resistive sensor device for monitoring carbon monoxide. Since sensor performances are affected by experimental factors, such as temperature, target gas concentration, and gas flow rate, the aim of the authors was to define the optimum working condition by performing multiple regression analyses. The investigated ranges of operating conditions were temperature from 300 to 480°C, carbon monoxide concentration from 100 to 200 ppm, and inlet-gas flow rate from 40 to 100 cm3/min. The results confirm that the applied systematic analysis is a powerful method for studying the direct and indirect effects of every experimental factor on sensor performance and for computing mathematical models with predictive ability, that are useful tools for defining the optimum chemiresistors’ operating conditions. In addition, mathematical models are able to be used as multiple-factor surface calibration for restive gas sensor devices.

Thermodynamic Analysis of Hydrogen Production from Ethanol in Supercritical Water Oxidation

2011 ◽  
Vol 110-116 ◽  
pp. 77-82
Author(s):  
Nawadee Srisiriwat
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Hydrogen Production ◽  
Thermodynamic Analysis ◽  
Supercritical Water ◽  
Water Oxidation ◽  
Equilibrium Composition ◽  
Operating Conditions ◽  
Molar Ratio ◽  
Hydrogen Yield

A thermodynamic analysis was performed for hydrogen production from ethanol reforming and oxidation in supercritical water (SCW) conditions. The minimization of Gibbs free energy was used to calculate the equilibrium composition to investigate the effect of operating conditions, pressure, temperature, H2O2:EtOH molar ratio and H2O:EtOH molar ratio, on product yields. The theoretical results indicated that the yields of hydrogen and carbon monoxide decreased as the pressure increased but a H2/CO ratio at atmospheric pressure was lower than that at SCW conditions. High temperatures increased the efficiency of hydrogen production although the amount of carbon monoxide also increased. The presence of oxygen led to great decreases in methane oxidized to carbon dioxide and water. The spending of some hydrogen oxidized to water resulting in a lower hydrogen yield. High H2O:EtOH ratios increased the yields of hydrogen and carbon dioxide but decreased the methane and carbon monoxide production. It is possible to conclude that high temperature, high H2O:EtOH ratio and low addition of oxygen should lead to best results in the SCWO of ethanol.

Sign in / Sign up

Export Citation Format

Share Document