Chemical engineering pumping systems

Transportation end uses are expected to become a significant outlet. Products under development include an engine valve cover, as are various housings such as those for od pumps, water pumps, starter motors, and certain transmission parts. These end uses employ PPS because it resists high temperatures and is also chemically resistant. Fuel system parts can employ the excellent chemical resistance of PPS, replacing nylon, if alcohol-based fuels are adopted to reduce emissions. 

As an initial (demonstration) application of the Icon/1000 control system, we automated two simultaneous acrylic lab polymerizations. In this application, heaters, agitators, and metering pumps are controlled. A batch proceeds automatically from state to state unless the operator intervenes through one of a series of color CRT touch screens allowing him to take complete manual control of the batch for as long as he desires. All important process variables are continually monitored and recorded. The entire control scheme was created, tested, and modified several times in the space of two months, without formal instruction, by a chemical engineer with little previous programming experience and no previous experience at all with this system. 

Fig 18. Experimental trickle-bed system A, tube bundle for liquid flow distribution B, flow distribution packing of glass helices C, activated carbon trickle bed 1, mass flow controllers 2, gas or liquid rotameters, 3, reactor (indicating point of gas phase introduction) 4, overflow tank for the liquid phase feed 5, liquid phase hold-up tank 6, absorber pump 7, packed absorption column for saturation of the liquid phase 8, gas-liquid disengager in the liquid phase saturation circuit. (Figure from Haure et ai, 1989, with permission, 1989 American Institute of Chemical Engineers.)... 

The production of vacuum (sub-atmospheric pressure) is required for many chemical engineering processes for example, vacuum distillation, drying and filtration. The type of vacuum pump needed will depend on the degree of vacuum required, the capacity of the system and the rate of air inleakage. 

Van Blarcom, Peter P., Yarway Corp., Bypass Systems for Centrifugal Pumps, Chemical Engineering, Feb. 4,1974. 

Redundant dispense engines. Redundant dispense engines have become fairly common in both pump- and non-pump-based slurry dispense systems. Since slurry is both chemically and mechanically aggressive, a backup dispense engine enables system maintenance without interruption of supply to the fab. 

The method just outlined and illustrated is route specific. It is very flexible and simple to use. It can also be easily computerized if the GP data can be fed in as numerical values. Here we have illustrated its use in the context of a cross-country pipeline, such as a crude oil, products, or perhaps slurry pipeline, which might be commonly encountered by chemical engineers. The method is completely adaptable to any hydraulic flow problem and could be used equally well for a short in-plant pumping system analysis. It can help the designer of flow systems to avoid sometimes subtle traps for slack flow and siphons that might not be immediately obvious if the mechanical energy equation is applied only once between the initial and final points of the flow system. 

Just as the electrical engineer selects resistors, capacitors, and transistors when designing an electric circuit, the chemical engineer selects valves, pumps, and flow meters to produce a flow system. The procedure followed in the design of a flow system is to determine ... 

Chemical reaction and mass transfer are two unique phenomena that help define chemical engineering. Chapter 8 described problems involving chemical reaction and mass transfer in a porous catalyst, and how to model chemical reactors when the flow was well defined, as in a plug-flow reactor. Those models, however, did not account for the complicated flow situations sometimes seen in practice, where flow equations must be solved along with the transport equation. Microfluidics is the chemical analog to microelectro-mechanical systems (MEMS), which are small devices with tiny gears, valves, and pumps. The generally accepted definition of microfluidics is flow in channels of size 1 mm or less, and it is essential to include both distributed flow and mass transfer in such devices. 

Rejowski, R. and Pinto, J. A novel continuous time representation for the scheduhng of pipeline systems with pumping yield rate constraints. Computers Chemical Engineering, 32(4) 1042-1066, 2008. 

Gathering system compressors Engine exhaust, CO (XTO) Gathering system compressors Ertgine mchaust. CH (EPA) Pneumatic devices chemical injection pumps. CH (EPA) Gathering system losses. CH (EPA)... 

Hansen AG, Na TY. (1966) Optimization of jet pump systems. ASME-EIC Fluids Eng. Conf., Paper No. 66-EEA4. American Society of Mechanical Engineers, New York, USA. Havelka P. (1997) Mass transfer capacity of gas-liquid reactors with ejector-type gas distributors. Ph.D. Thesis, Prague Institute of Chemical Technology, Czech Repubhc. cf. Dierendonck et al. (1998). 

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