Gas conditioning

The dilute gas condition can be stated as the condition that the available volume per particle in the container is much larger that the volume of the particle itself In other words... 

Flow and Performance Calculations. Electro dynamic equations are usehil when local gas conditions (, a, B) are known. In order to describe the behavior of the dow as a whole, however, it is necessary to combine these equations with the appropriate dow conservation and state equations. These last are the mass, momentum, and energy conservation equations, an equation of state for the working duid, an expression for the electrical conductivity, and the generalized Ohm s law. 

Materials and Reactions. Candle systems vary in mechanical design and shape but contain the same genetic components (Fig. 1). The candle mass contains a cone of material high in iron which initiates reaction of the soHd chlorate composite. Reaction of the cone material is started by a flash powder train fired by a spring-actuated hammer against a primer. An electrically heated wire has also been used. The candle is wrapped in insulation and held in an outer housing that is equipped with a gas exit port and rehef valve. Other elements of the assembly include gas-conditioning filters and chemicals and supports for vibration and shock resistance (4). 

Consumption of ethanolamines ia the United States has changed dramatically since the 1960s. Consumption ia gas conditioning appHcations has peaked and chemical processing intermediates (captive use for ethyleneamine and surfactant appHcations) has increased significantly. 

Mild steel can be used for transport and storage if product discoloration is not a problem, such as in gas conditioning appHcations. Contact with copper, brass, and other copper alloys may cause corrosion of the metal. 

Work continues on improving the efficiency of this process, such as for freeing the alkan olamine from heat-stable salts that can form (125). Formulations have been developed which inhibit degradation of mono- and diethanolamine in processing (126). Models (127), computer programs (128), and kinetics and enthalpies (129—136) have been developed to help determine equiUbria of the acid gas—alkanolamine—water system. Additional references relate to the use of tertiary alkan olamines, such as triethanolamine, for gas conditioning (137—139). 

The Sulfinol gas conditioning process of Shell uses dksopropanolamine in a sulfolane solvent system. This system also increases gas capacity with improved efficiencies (152). 

Gas Conditioning Fact Book, The Dow Chemical Company, Midland, Mich., 1962. 

V. Kwong, R. E. Meissner III, 45th Annual Okla. Univ. Eaurance Reid Gas Conditioning Conference, Norman, Ok, Eeb. 26—Mar. 1, 1995. 

N. I. DowHng and J. B. Hyne, 44th Annual Oklahoma Universif Eaurence Reid Gas Conditioning Conference, Norman, OHa., Eeb. 27—Mar. 2,1994. 

L. D. Polderman, "The Glycols as Hydrate Poiat Depressants ia Natural Gas Systems," Proceedings of the Gas Conditioning Conference University of Oklahoma, Norman, 1958. 

B. H. Engler and co-workers. Catalytic Reduction of NO with Hydrocarbons under Eean Diesel Exhaust Gas Conditions, SAE 930735, Society of Automotive Engineers, Warrendale, Pa., 1993. 

The process gas of ethylene plants and methyl tertiary butyl ether plants is normally a hydrogen/ methane mixture. The molecular weight of the gas in such processes ranges from 3.5 to 14. The tliermodynamic behavior of hydrogen/methane mixtures has been and continues to be extensively researched. The gas dynamic design of turboexpanders, which are extensively used in such plants, depends on the equations of state of the process gas. Optimum performance of the turboexpander and associated equipment demands accurate thermodynamic properties for a wide range of process gas conditions. 

The velocity ratio is the single most important factor in determining the performance of an expander. The velocity ratio, p, is a dimensionless parameter, relating the physical size of the expander to the gas conditions being considered. It is defined as ... 

From dimensional analysis, the expander blade speed, u, is directly proportional to the wheel diameter, D, of the expander, multiplied by the rotational speed, N, of the expander, both of which are dependent on the volume flow of gas and mechanical stresses. The equivalent velocity energy, C, is dependent on the inlet gas conditions to the expander and can be directly translated into available energy by the following equation ... 

As mentioned earlier, because the number of stages has a significant effect in determining the velocity ratio, consider the effect the gas conditions have in determining tlie optimum number of stages. To make this determination, the following parameters should be considered ... 

Some manufacturers have experienced die above mentioned Ni3S2 scale formation phenomenon under certain gas conditions, which led to die failure of a rotating blade. One such experience involved a fracture dial was distinctly intergranular with evidence of secondary intergranular cracks or grain separation across die fracture. Intergranular facets of die fracture were sharp and distinct with little evidence of any ductile mode. The fracture appeared to have occurred in a brittle intergranular mode. 

To fully understand the formation of the N13S2 scale under certain gas conditions, a brief description needs to be given on the chemical aspects of the protective (chromium oxide) Ci 203/(nickel oxide) NiO scales that form at elevated temperatures. Under ideal oxidizing conditions, the alloy Waspaloy preferentially forms a protective oxide layer of NiO and Ci 203 The partial pressure of oxygen is such that these scales are thermodynamically stable and a condition of equilibrium is observed between the oxidizing atmosphere and the scale. Even if the scale surface is damaged or removed, the oxidizing condition of the atmosphere would preferentially reform the oxide scales. 

When the pollutant loading is exeeptionally high or consists of relatively large particles (> 2 /tm), venturi scrubbers or spray chambers may be used to reduce the load on the ESP. Much larger particles (> 10 /tm) are controlled with mechanical collectors such as cyclones. Gas conditioning equipment to reduce both inlet concentration and gas temperature is occasionally used as part of the original design of wet ESPs (AWMA, 1992 Flynn, 1999). 

A major market which has developed for fabric fillers is for the control ot flue-gas fly ash in the utility industry. This market is primarily at the expen.se of electrostatic precipitators. Fabric filters have the inherent advantage of operating at a high level of collection efficiency tor a wide range of dust and gas conditions. 

A superheat exchanger is not needed for a centrifugal compressor system as far as gas condition is concerned. It may be a good unit as fer as other aspects of the process are involved. The centrifugal compressor requires only a suction knock-out drum to remove entrained liquid and foreign particles. 

P = absolute pressure, psia, at flowing gas conditions, or = may be operating pressure, psia Pl = line pressure, psi abs... 

Figure 4. Effect of number of equilibrium stages on heating value and H2 content of product gas Conditions 20 atm, 371 °C, and Hu.CO = 3 1...

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