Gas during process

A chemical agent in a formulation that provides gas during processing. The gas may result from heating or from a chemical reaction. Example Water reacts with isocyanate material to produce carbon dioxide gas in one process for making polyurethane (solid) foam. 

In the case ofbf/N2 implantation into Si, the buried insulating SisN4 layer is formed in Si N. The structure of SOI-like structures prepared by annealing of Si N, similarly as in the case of Si 0, depends on HP exerted by ambient gas during processing [4-6]. However, due to still unsolved problems (e.g. 

Relative to the process streams, emissions from auxiUary equipment and flares are small. Some ethylene oxide units use gas-fired turbines to feed air or ethylene (109). These result in unbumed hydrocarbon and possible NO emissions. Also, most ethylene oxide units have flares to vent the process gas during upsets. Data is scarce, but estimates indicate that flaring of process gas occurs once to twice a year (109). 

The orifice-riser distributor is designed to lay the hquid carefully onto the bed, with a minimum of contact with gas during the process. It can be designed to provide a large number of liquid streams, with the limit of sufficient liquid head to provide uniform liquid flow through the orifices. The gas risers must oe designed to accommodate the expected variations in flow rate, often with a minimum of pressure drop. For veiy distribution-sensitive packings, it is necessaiy to include pour points in the vicinity of the column wall (to within 25 mm). 

Critical factors. In general, porosity is caused by the entrapment of gas during the welding process or during solidification of the weld metal. Surface contamination may provide a gas source during the welding operation. 

An electrostatic precipitator is used to remove more tar from coke oven gas. The tar is then sent to storage. Ammonia liquor is also separated from the tar decanter and sent to wastewater treatment after ammonia recovery. Coke oven gas is further cooled in a final cooler. Naphthalene is removed in a separator on the final cooler. Light oil is then removed from the coke oven gas and is fractionated to recover benzene, toluene, and xylene. Some facilities may include an onsite tar distillation unit. The Claus process is normally used to recover sulfur from coke oven gas. During the coke quenching, handling, and screening operation, coke breeze is produced. The breeze is either reused on site (e.g., in the sinter plant) or sold offsite as a by-product. 

In addition to being the most widely used disinfectant for water treatment, chlorine is extensively used in a variety of products, including paper products, dyestuffs, textiles, petroleum products, pharmaceuticals, antiseptics, insecticides, foodstuffs, solvents, paints, and other consumer products. Most chlorine produced is used in the manufacture of chlorinated compounds for sanitation, pulp bleaching, disinfectants, and textile processing. It is also used in the manufacture of chlorates, chloroform, and carbon tetrachloride and in the extraction of bromine. Among other past uses, chlorine served as a war gas during World War I. 

Ethylenethiourea (ETU) is a toxic decomposition product/metabolite of alky-lenebis(dithiocarbamates). This compound could be generated during processing of treated crops at elevated temperature. Different chromatographic methods to determine the residue levels of ETU have been published. After extraction with methanol, clean-up on a Gas-Chrom S/alumina column and derivatization (alkylation) with bro-mobutane, ETU residues can be determined by GC with a flame photometric detector in the sulfur mode. Alternatively, ETU residues can also be determined by an HPLC method with UV detection at 240 nm or by liquid chromatography/mass spectrometry (LC/MS) or liquid chromatography/tandem mass spectrometry (LC/MS/MS) (molecular ion m/z 103). ... 

But in sonicated condition hexamminenickel(II) ions did not form, because of the degassing effect of the ultrasound leading to the removal of ammonia gas during the sonication process. Because of this reason the turbidity in sonicated sample did not come to the zero value (Table 9.8). Ultrasound was also effective in the reduction of crystallization time by 50% in Ni-chloro and by 25% in Ni-thiocyanato complex, which, however, remained the same in NiSO.4 solution as shown in Table 9.10. 

All the gas laws described so far worked only for a given sample of gas. If a gas is produced during a chemical reaction or some of the gas under study escapes during processing, these gas laws do not apply. The ideal gas law works (at least approximately) for any sample of gas. Consider a given sample of gas, for which... 

The average quantity and composition of gases from AC1 and AC2 are shown in Table 3. The N2 free gases contained small quantities of CO2, H2S, and other gases which are probably the result of thermal coal decomposition. Only 2 weight percent of the as-fed coal goes to gas during the first step of the process. This amount of gas formation probably cannot be avoided. 

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