Surface temperature, hydrocarbon pollution

Biogenic VOC and NO emissions are calculated on-line based on land use data, simulated surface temperature and radiation. Anthropogenic emissions of primary pollutants, like NOx, SO2, and hydrocarbons, as well as emissions of primary particulate matter have to be supplied either at hourly intervals or as yearly data from gridded emission inventories. Validation studies with MCCM have shown its ability to reproduce observed meteorological quantities and pollutant concentrations for different conditions and regions of the Earth (Forkel and Knoche 2006 Forkel et al. 2004 Grell et al. 1998, 2000 JazcUevich et al. 2003 Kim and Stockwell 2007 Suppan and Skouloudis 2003 Suppan and Schadler 2004 Suppan 2010). 

Temperature resistant oxide supports for catalytic active phases are necessary for the catalytic combustion of hydrocarbon pollutants in the field of environment as well for energy production through hydrocarbon clean combustion. Four commonly used pure support oxides in catalysis silica, alumina, titania, and zirconia were synthesised by the sol-gel and aerogel methods and, in parallel, the same oxides were doped with yttria. Pure yttria aerogel was also made and characterised. Heat treatments were performed from ambient up to 1200°C and BET surface areas and XRD patterns were recorded after heat treatments at 300, 600, 900 and 1200 °C for pure and doped oxides, respectively. 

Monitoring near surface existence of hydrocarbon polluted surfaces in the Burgan Oil field area was attempted by Saif ud din et al. [20, 21]. The researchers used the land surface temperature (LST) as an indicator for hydrocarbon pollution. 

The LST and total petroleum hydrocarbon (TPH) are positively correlated. The methodology followed is based on the fact that most of the satellites carry a thermal infra-red band which can be used for LST estimation. The spatio-temporal variation in the thermodynamic properties of surface material has been mapped in order to identify hydrocarbon polluted surfaces using Landsat TM data. Emissivity is a strong indicator of compositional variation in silicate minerals which make up the bulk of the earth s surface material. Emissivity affects the apparent temperature due to changes in the thermal properties of materials (conductivity, density, capacity, and inertia). There are several algorithms proposed to estimate LST from remotely sensed data. The most common of these are mono-window and split window methods [22-25], the latter was used initially to estimate sea surface temperature. 

Fig. 30 Correlation between surface temperature and hydrocarbon pollution...

The study of porous carbon materials using IGC is frequently carried out by adsorption of hydrocarbons at the zero surface coverage. This is doubly useful because it gives information on the textural characteristics of the carbon materials and also the adsorption capacity of these molecules is obtained. It should be pointed out that this adsorption capacity is obtained under dynamic conditions and frequently at relatively high temperatures, i.e. at the experimental conditions very close to the real situations at which the carbon materials are used (for instance to eliminate atmospheric pollutants) [6]. 

The simulation starts with a temperature level of 20 C over the entire length of the exhaust pipe. Five seconds after the engine start the heated brick reaches a temperature of approx. 400 C. At this time, the reduction of the hydrocarbon emmisions is still low because of the very small catalytic surface of the heated brick. As a result of the good convective heat transport, the second brick of the EHC reaches the ignition temperature level fast. Thus the conversion of the pollutants can be increased to 80-90 % within 9 s. The electrical heating of the first brick plus the reaction heat set free at the EHC help to warm-up the main catalyst and total combustion of the hydrocarbons is completed after only 25 s. 

Soot formation is commonly observed in the pyrolysis or combustion process of simple hydrocarbons and coals. Soot does great harm to people s health through carcinogenic effects and the presence of soot in air also leads to visibility reduction, globe temperature decrease, and acid deposition. Soot can suspend in the air for up to 1 month and can be delivered by wind to distant places, which causes wide range pollution. Soot suspended in flames is important to combustion systems because it will significantly enhance radiative heat transfer due to its large surface area (Fletcher et al., 1997). 

Some of the oil lakes and tarcrete deposits are covered by a thin veneer of sand which has obscured them. The depth of burial has increased over the years however, the thickness of sand sheet has not increased in recent years in the study area [39]. High temperatures in sununer months, imparts mobility to the tar and soot deposits at the surface, and winter rains leach out hydrocarbon fractions which percolate down with the water [40]. Consequently, the depth of pollution observed at several places, varies from a surface veneer to a maximum depth of 4p,. 

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