Gaseous emissions sulfur oxides

The gaseous component typically contains hydrocarbons, hydrogen sulfide, ammonia, mercaptans, solvents, and other constituents, and is either discharged directly to the atmosphere or is combusted in a flare. The major air emissions from blowdown systems are hydrocarbons in the case of direct discharge to the atmosphere and sulfur oxides when flared. 

Emissions monitoring is essential in controlling industrial environments and processes to ensure good air quality standards are maintained. It is also required in order that the various regulations and guidelines related to air quality are met. In addition to gaseous emissions, such as sulfur dioxide, carbon monoxide, nitrogen oxides, hydrocarbons, and many others, the emissions of particulate material and heavy metals must also be controlled. 

There is much concern about the emissions which result when fuel sulfur combusts (i.e., sulfur oxides). These gaseous products further react to form environmental pollutants such as sulfuric acid and metal sulfates. Active sulfur and certain sulfur compounds can corrode injection systems and contribute to combustion chamber deposits. Under low-temperature operating conditions, moisture can condense within the engine. Sulfur compounds can then combine with water to form corrosive acidic compounds. 

In a new process proposed by Kellogg the oxidation of HCI makes use of nitrosyl-sulfuric acid (HNSOs) at 4 bar and 260-320 °C [9], The amount of byproducts diminishes drastically raising the overall yield over 98%. The gaseous emissions are reduced practically to zero. Chlorinated waste from other processes may be incinerated to HCI, and in this way recycled to the manufacturing of VCM. The process is safer because the contact of hydrocarbon mixtures with oxygen is eliminated. A capital cost reduction of 15% may be estimated compared with the oxy-chlorination process. 

The emission of gaseous pollutants such as sulfur oxide, nitrogen oxide, and toxic gases as a result of a variety of industrial processes has become a serious environmental concern, especially in specific parts of the world. As a result, sensors are needed to monitor the concentration of various contaminants, which can prevent or limit uncontrolled releases of toxic compounds. 

Other emissions include gaseous emissions such as carbon monoxide, hydrocarbons, sulfur oxides, nitrogen oxides, hydrogen oxides, VOCs, and aldehydes. Gaseous anissions are much lower than the particulate, generally mounting to less than 0.5 kg/t. The EPA emission factors for various gaseous pollutants in asphalt concrete manufacture are listed in Table 53.16. 

If it can be assumed that water used for cooling purposes in a coal utility plant is predominantly the type that passes through cooling towers, the gaseous emissions from such a plant will be carbon dioxide (CO2), sulfur oxides (SOx, where x = 2 or 3), nitrogen oxides (NOx, where x = 1 or 2), as well as sundry other sulfur compounds of which hydrogen sulfide (H2S), carbonyl sulfide (COS), carbon disulfide (CS2), and mercaptans (RSH) are examples. 

Thermal-oxidative degradation leads to gaseous emissions that can already be detected below 100 °C, Fig. 4.71 [626]. These gases consist mainly of SO, and, to a lesser degree, of HjS the content of other very volatile sulfurous gases is low. The... 

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