Startup strategy

Verwijs, J. W., H. van den Berg, and K. R. Westerterp (1996). "Startup Strategy Design and Safeguarding of Industrial Adiabatic Tubular Reactor Systems. AIChE Journal 42, 2 (February), 503-15. 

Devise a fast-fill-and-hold startup strategy for the reaction of Problem 14.1. 

When the column initially contains an inert gas, the flash temperature is considerably higher when the column is pressured than when the column is depressured (compare Fig. 12.26 and c). On the other hand, overchilling at an elevated pressure can at times be more detrimental to the metal than overchilling at atmospheric pressure, because the minimum safe working temperature of the metal increases with column pressure. Both effects should be considered when devising the startup strategy and the only available gas is inert in most cases, it is still better to pressure up. 

Because of the large multiplicity regions, multiple steady states of the TAME process were also verified experimentally as illustrated in Fig. 10.15 [71, 73, 85). For this purpose suitable startup strategies were developed by means of dynamic simulation to operate the column directly into the desired steady state. Further, it was... 

Startup and Shutdown Strategies. In addition to safe operation, the usual goal of a reactor startup is to minimize production of off-specification material. This can sometimes be accomplished perfectly. 

Neither method will achieve a bumpless startup for complex kinetic schemes such as fermentations. There is a general method, known as constant RTD control, that can minimize the amount of off-specification material produced during the startup of a complex reaction (e.g., a fermentation or polymerization) in a CSTR. It does not require a process model or even a realtime analyzer. We first analyze shutdown strategies, to which it is also applicable. 

Suppose there are two parallel, first-order reactions in a steady-state CSTR. Show that neither the fed-batch nor fast-fill-and-hold strategies can achieve a bumpless startup if the reactions have different rate... 

Obviously the aim in operating the reactor cascade is to ensure operation at the most favourable conditions, and for this both the startup policy and control strategy are important. 

A variety of control schemes can be employed and are of great importance, since the reactor scheme shows a multiplicity of possible stable operating points. Obviously the aim in operating the reactor cascade is to ensure operation at the most favourable conditions, and for this both the startup policy and the control strategy are important. This example is taken from the paper of Mukesh and Rao (1977). 

Jennings, A., and Tennant, M. (2005). Discovery strategies in a biopharmaceutical startup maximising your chances of success using computational filters. Curr. Pharm. Des. 11, 335-344. 

As the flow of new chemical molecules dries up, the chemical industry needs to look to other sources of innovation in addition to traditional chemical research, and also ensure that it captures the maximum value of each innovation. In order to do both successfully, chemical companies have to break down their traditional inward orientation, determine explicit strategies for innovation, and mimic the business patterns and mentality of successful venture capitalists and new startups to take advantage of outside resources. Among the attractive new technological sources of innovation that they should explore are biotechnology and e-commerce (see Chapters 6 and 7). 

In order to promote the generalisation of DWC in industrial application it is necessary to provide reliable design methodologies, but it is also very important to define strategies for a convenient startup of the column. The present paper proposes a new dynamic model for a DWC and applies it to formulate the startup control. 

For Biogen, see Derdak, ed.. International Directory, vol. 14 (1996), pp. 58-60 Lawrence M. Fisher, The Rocky Road from Startup to Big Time Player Biogen s Triumph against Odds, Strategy Business 8 (1997) 55-63. McKelvey, Evolutionary Innovation, p. 132, tells of Eli Lilly s contact with Gilbert. 

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