Increasing flexibility in the design of wastewater treatment processes

An increasing focus on the design of biological nutrient removal processes and the development of new and varied designs (propelled by increasing needs for higher efficiencies and lower costs) has introduced the need for improved methods of design for wastewater treatment plant (WWTP) processes. These design methods may include studies of process operability (i.e., flexibility, controllability, and resilience). This paper focuses on flexibility and the tools available to facilitate the study of flexibility. A simple example is used to demonstrate a method of flexibility analysis and a more complex example is used to illustrate the significance of the results to WWTP process design. The most significant result is that the flexibility of a process can sometimes be significantly increased with negligible increases in capital costs.

[1]  C. Y. Wen,et al.  Optimal Design of Systems Involving Parameter Uncertainty , 1968 .

[2]  B. Linnhoff,et al.  Sensitivity tables for the design of flexible processes (1) ― How much contingency in heat exchanger networks is cost-effective? , 1986 .

[3]  C. Floudas,et al.  Active constraint strategy for flexibility analysis in chemical processes , 1987 .

[4]  Ana M. Eliceche,et al.  Flexibility analysis leads to a sizing strategy in distillation columns , 1996 .

[5]  Ignacio E. Grossmann,et al.  An index for operational flexibility in chemical process design. Part I: Formulation and theory , 1985 .

[6]  S. Fararooy,et al.  Process controllability toolbox (PCTB) , 1993 .

[7]  H. Stehfest.  An operational dynamic model of the final clarifier , 1984 .

[8]  Ignacio E. Grossmann,et al.  Evaluation of design flexibility in distillation columns using rigorous models , 1995 .

[9]  David Bogle,et al.  Controllability analysis of an industrial polymerization reactor , 1996 .

[10]  Paul Lant,et al.  Output strutural controllability: a tool for integrated process design and control , 1998 .

[11]  Ignacio E. Grossmann,et al.  Optimal process design under uncertainty , 1983 .

[12]  Atsunobu Ichikawa,et al.  Synthesis of Optimal Process Systems with Uncertainty , 1974 .

[13]  J. D. Perkins,et al.  Assessing controllability of chemical plants , 1985 .

[14]  Ignacio E. Grossmann,et al.  An index for operational flexibility in chemical process design. Part I , 1983 .