ENVIRONMENTAL PROCESS CONTROL
LABORATORY
(MODERN METHODS OF MANAGING WATER QUALITY)Purpose
Any hope of achieving significant results in developing and applying models of the dynamic behavior of environmental systems is strongly dependent upon access to field data of the highest possible quality. The Environmental Process Control Laboratory, a completely integrated facility for monitoring the behavior of environmental systems in real-time, was designed expressly for the goal of maximizing our program's independence of action in assembling its data bases. The Laboratory comprises two mobile trailers housing all the components necessary to have a sample of water or wastewater pumped from a given field location, its characteristics of quality analyzed automatically within the trailer units, and the resulting streams of high-density observations communicated to a remote (host) location. The Laboratory has been designed for deployment in a variety of contexts, but principally in the study of municipal and industrial wastewater treatment, protection of surface water quality, aquaculture, and groundwater contamination. Its purpose is to support the development of process models, signal processing software, and, where appropriate, procedures of automatic control, decision support, and information management for these systems.The objective of this class is to provide instruction and practical training in the operation and maintenance of all those technical components — from tubing to telemetry — necessary for the Laboratory to function reliably and with maximal quality of performance. Successful operation of the EPCL, and the replication of similar, albeit less ambitious, applications of this technology, will require students to acquire a rare amalgam of skills from this class. First, for example, there is the basic matter of fluid mechanics: if sub-standard pumping and sample-flushing routines are not detected, electronic signal-averaging procedures will generate erroneous observations. Second, a basic knowledge of chemistry is required for preparing reagents and for appreciating why precision in such preparations is of paramount importance for the successful functioning of a monitor. Third, knowing when and how to replace spent components of an instrument will depend upon an intimate understanding of several types of sensor technology. Fourth, implementing specific operating cycles for the on-line respirometers, designed to investigate all manner of substrate-biomass interactions, will be far from effective in the absence of requisite skills in biochemical process engineering. And last, but by no means least, there is the ubiquity of electronics in the EPCL: without a facility for connecting, re-connecting, re-wiring, and replacing electronic components, we shall make but very little progress indeed.
Outline
A sound appreciation of historical context and current practice in the water industry is important. The class reviews a century or so of problems and solutions in water pollution control, focusing on requirements for sampling and monitoring. This is treated from the distinctive perspective of the third routine of Control and Systems Theory (as established through FORS 6150). Each era of pollution — from pathogen propagation in the nineteenth century, through gross pollution from sewage in the early twentieth century, and so on (up to the present day) — is interpreted through the template of a feedback control scheme, with assessment of the dominant components of the frequency spectrum of environmental variability relevant to the given era. The pedagogical point is that the speed with which things fluctuate and vary in time determines, in principle, the frequency with which sampled observations of that behavior should be made. Students can develop from this their own views on the relevance, or otherwise, of the EPCL to solving contemporary problems of Integrated Urban Water Management (IUWM), nested with watershed management, or Integrated Water Resources Management (IWRM). Attaining this essential goal is accompanied by "an engineer's guide to water quality" and discussion of the life cycle of civil engineering projects. Not surprisingly, a success story in implementing the EPCL, from start to finish, is recounted.Students receive instruction in basic, good laboratory practices and rudimentary data management, and are introduced to the more advanced aspects of data management associated with signal processing (as treated elsewhere in FORS 8150). A site visit to a local wastewater treatment facility is part of the class, its purpose being to assist students in assessing current practice in instrumentation, control, and automation. There is a term project gathered around a web-based operational support and training system for the EPCL. Each student is assigned a particular monitor (for example, that for measuring ortho-phosphate concentration), given instruction in how to operate the monitor and in how to develop web pages, and then required to report on their success in setting up a web-based scheme for future students to acquire the same skills through a self-study or distance-learning process.
Reference is made to material available in the book by Ingildsen and Olsson on "Get More Out of Your Wastewater Treatment Plant".