Cooling inter-stage

The cooling of the inter-stage compressor air by injecting water is also another very effective way for getting more power from the gas turbine. The problem in most units is that there is no convenient place to inject the water. The gas turbines would require substantial modification to install such a system. Care would have to be taken that any modification would not affect the integrity of the system. This type of a system is very effective in units where there is a low and high-pressure compressor, providing a very convenient place to inject the water. This type of compressor are mostly available in aeroderivative units. 

If possible, design for maximum water knock-out using compression and cooling alone. At 50°C (120°F) inter-stage this corresponds to about (500 to 900 pisa) for the penultimate stage discharge (note the previous point)... 

FIGURE 13.1 Types of fixed bed reactors, (a) Axial flow fixed bed reactor Up or down flow, single or multi-stage, with or without inter-stage cooling, single or multi-tubular, (b) Radial flow fixed bed reactor Radially inward or outward flow, straight or reverse flow (direction of inlet and outlet is same or opposite to each other). 

Industrially, the shift reaction is run in adiabatic reactors. Thus, there exists the dilemma of slow catalyst kinetics where the equilibrium is favorable (low temperature) and fast catalyst kinetics where the equilibrium is unfavorable (high temperature). This problem is solved by operating the reaction in one to three sequential reactors with inter-stage cooling and subsequently lower inlet temperatures. 

INTER-STAGE DIFFERENTIAL - In a multistage HVAC system, the change in temperature at the thermostat needed to turn additional heating or cooling equipment on. 

Optimize compressor operation, reduce friction and air leakages in air distribution system, low pressure drop air coolers and instruments, reduction of air leaks, use of heat of compression dryers, cool compressor suction air, waste heat recovery at compressor inter-stage coolers, better control Install additional compressors in parallel. Use of heat of compression dryer Use cogeneration, ORC, KC or (hydraulic) power recovery turbines... 

Figure 11.6 Three-stage steam ejector system with water-cooled inter- and after-condensers (Case IB).

Refrigeration system optimization/debottlenecking using snb-cooling in the inter-stage compressor coolers. This has the potential to increase the overall throughput, but the GHG reduction potential may be limited to a slight increase in compressor... 

Giroux et al. proposed a two-stage approach with inter-stage cooling for the preferential oxidation of CO for monolithic reactors. They found that the addition... 

Figure 10.43 Defining the work of a two-stage compressor with inter-stage cooling.

Solution Methane compression from 1 to 60 bar is assumed to be carried < a three-stage machine with inter- and after-cooling to 300 K and a comp efficiency of 75 percent. The actual work of this compression is estimated as 1,C per kilogram of methane. The fraction of the methane that is liquefied z is calcul by an energy balance ... 

The ammonia synthesis loop consists of two stages. Makeup gas is compressed in a two-stage inter-cooled compressor, which is the low-pressure casing of the syngas compressor. Discharge pressure of this compressor is about 110 bar. An indirectly cooled once-through converter at this location produces one third of the total ammonia. Effluent from this converter is cooled and the major part of the ammonia produced is separated from the gas. 

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