Carbon dioxide methane equivalents

Natural gas, found in geological accumulations, normally refers to the gaseous fossil-based equivalent of oil. Its composition varies widely, from high concentrations of nitrogen and carbon dioxide to (almost) pure methane. In general, it contains low concentrations of the higher (saturated) hydrocarbons, which influence the physical properties and may present condensation problems in high-pressure transport lines. 

Each greenhouse gas differs in its ability to absorb heat in the atmosphere. HFCs and PFCs are the most heat-absorbent. Methane traps over 21 times more heat per molecule than carbon dioxide, and nitrous oxide absorbs 270 times more heat per molecule than carbon dioxide. Often, estimates of greenhouse gas emissions are presented in units of millions of metric tons of carbon equivalents (MMTCE), which weighs each gas by its GWP value, that is, Global Warming Potential. 

Fig. 4.1 Greenhouse gas emission such as carbon dioxide (C02), methane (CH4) and nitrous oxide (N20) converted to C02 equivalents, by sector in 2004 (Barker et al. 2007). Agriculture and forestry together play a major role in the global fluxes of the greenhouse gases carbon dioxide, nitrous oxide and methane...

The data source is GREET1.6 23 except for the PV electricity and hydrogen by PV electrolysis primary energy and CO2 equivalent emissions estimates, which are original to this study. The CO2 equivalent emissions are carbon dioxide, nitrous oxide, and methane. 

Methanogenesis from methanol occurs by its disproportionation to methane and carbon dioxide (Reactions (5) and (5A), Table 2). Reducing equivalents derived from the oxidation of one methanol to CO2 are used to reduce three methanols to CH4. 

Table II contains representative over-all reactions for methane fermentations of acetate and hydrogen, respectively. Acetate fermentation is mediated by heterotrophic organisms which use acetate as a carbon source for synthesis as well as energy. For reaction B , Ek represents the electron equivalents of the electron donor converted for energy per electron equivalent of cells synthesized. Hydrogen fermentation, by contrast, is mediated by autotrophic organisms which use carbon dioxide, acetate, or some other carbon source for cell synthesis. In the equation shown in Table II acetate was assumed to be the carbon source used as found for this fermentation by Bryant (I). E has the same definition as for heterotrophic growth.

Mercury bis-a-acetyl-a-isopropyl or Mercury-bis-aceto-di-methyl-methane, [CHgCO.CMeg—JgHg.—Mercuric dimethyl aceto-acetate is heated in a vacuum at 90 C., when it is found to lose two molecular equivalents of carbon dioxide, which is shown by the loss in weight. The resulting mass is extracted with acetone, and the solvent removed m vacuo, the product isolated melting at 120 C. It is soluble in acetone, alcohol, toluene, or xylene, but only slightly soluble in ether. Mercuric sulphide is split off from it by the action of ammonium sulphide, but no mercuric oxide is formed when sodium hydroxide is added. The compound soon decomposes with the deposition of metallic mercury. 

At steady state, the carbon leaving the system as carbon dioxide and methane fluxes into the overlying water or air, will be equivalent to the amount of carbon remineralised in the column below, integrated over its depth. Dissolved organic carbon (DOC) exchange from pore-water to sea water is thought to have a minor effect on the mass balance (Martens ... 

Classification is followed closely by characterization To every substance is assigned a potential impact in the impact category under study. The potential impact of a substance is set in relation to a dominant factor in the category. The reference unit for example, the greenhouse potential is 1 kg carbon dioxide. The values which result from it are described as impact factors. For instance, the emission of 1 kg of methane which has a stronger greenhouse effect corresponds to the emission of 24.5 kg CO2 methane therefore gets the equivalent value of... 

A carbon offset is a kind of financial instrument one offset represents a reduction of one metric ton of carbon dioxide or its equivalent in other greenhouse gases, such as methane. The average car getting thirty miles to the gallon and being driven 12,000 miles a year produces about 3.5 tons of carbon dioxide, so it would require 3.5 offsets to balance it out and make the driver carbon neutral — 20 to 50, depending on the project the offset is used to finance. Burt s Bees purchases about 25,000 worth of offsets annually. 

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