Chemical process piping systems

Figure 2.4 shows stress corrosion crack growth of a 321 SS in response to chloride and temperature excursions, the initial and the final stress intensity factors are 16.1 MPam and 22.3MPam 2, respectively. Figure 2.5 illustrates SCC in a 316 stainless steel chemical processing piping system. 

Figure 2.5 Stress corrosion cracking in a 316 stainless steel chemical processing piping system. (Reproduced with permission from Daubert Cromwell.)...

In recent years new ec]uipment has been invented, chemical processes, piping materials, valve designs, and new teehnologies not eonsidered when these formulas were developed with eold water in the 19th century. There is a need to measure the aetual losses onee an industrial plant is eommissioned and operations begin. I he authors of this book have developed a formula that permits the measurements of these losses in a live functioning system. Here it is ... 

Myriad FRP products are available for either the repair or the outright replacement of existing structures. In addition to chemical-process pipes and tanks, FRP composite products include structural shapes, bridge systems, grating, handrail ladders, etc. 

Deutsch, D. J. and the Staff of Chemical Engineering, Process Piping Systems, McGraw-Hill Publications Co., New York, 1981. 

Wastage is pronounced in equipment contacting high-pH fluids. Chemical process equipment, heat exchangers, water-cooled process reactors, valving, transfer pipes, and heating and cooling systems are often affected. 

The Guidelines for Process Equipment Reliability Data with Data Tables covers a variety of components used in the chemical process industry, including electrical equipment, analyzers, instrumentation and controls, detectors, heat exchangers, piping systems, rotating equipment (pump, compressor, and fan), valves, and fire protection systems. 

This chapter shows that chemical process systems may fail and have serious consequences to the workers, public and the environment. Comparing with Chapter 6, chemical processes are similar to the processes in a nuclear power plant, hence, they may be analyzed similarly because both consist of tanks, pipes heat exchangers, and sources of heat. As an example of analysis, we analyze a storage tank rupture. 

There is a need in many chemical processes for protection against propagation of nnwanted combnstion phenomena snch as deflagrations and detonations (inclnding decomposition flames) in process eqnipment, piping, and especially vent manifold systems (vapor collection systems). 

Piping system Main steam Process steam Feedwater Raw water Treated water Potable water Aux. cooling system Firefighting system Clarified water Filtered water Water-intake system Circulating-water system Chemical dosing Station drains Fuel oil Fuel gas... 

In the majority of chemical processes heat is either given out or absorbed, and fluids must often be either heated or cooled in a wide range of plant, such as furnaces, evaporators, distillation units, dryers, and reaction vessels where one of the major problems is that of transferring heat at the desired rate. In addition, it may be necessary to prevent the loss of heat from a hot vessel or pipe system. The control of the flow of heat at the desired rate forms one of the most important areas of chemical engineering. Provided that a temperature difference exists between two parts of a system, heat transfer will take place in one or more of three different ways. 

Many physio-chemical processes involve a time delay between the input and output. This delay may be due to the time required for a slow chemical sensor to respond, or for a fluid to travel down a pipe. A time delay is also called dead time or transport lag. In controller design, the output will not contain the most current information, and systems with dead time can be difficult to control. 

Process simulation, 20 710, 728-730 Process specific piping system, in fine chemical production, 11 429-430 Process-stream purification, 13 620 Process synthesis, 13 218 26 999... 

No doubt the chemical process operators watched in amazement as they started up the filter system with the newly replaced cartridges and they observed rusty colored smoke. Investigators theorized the tin spontaneously caught fire within the hot chlorine atmosphere. Apparently, the cartridges burned with sufficient heat to initiate an iron-in-chlorine fire on the filter body. Operations promptly blocked the upstream chlorine valves and the fire continued to burn until the fire quickly consumed the chlorine gas. The fire destroyed the steel shell of the filter and several inches of downstream piping, but no injuries were reported. 

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