Assessment of Treatment Plant Performance and Water Quality Data: A Guide for Students, Researchers and Practitioners
75 Excel spreadsheets are available to download here.
This book presents the basic principles for evaluating water quality and treatment plant performance in a clear, innovative and didactic way, using a combined approach that involves the interpretation of monitoring data associated with (i) the basic processes that take place in water bodies and in water and wastewater treatment plants and (ii) data management and statistical calculations to allow a deep interpretation of the data.
This book is problem-oriented and works from practice to theory, covering most of the information you will need, such as (a) obtaining flow data and working with the concept of loading, (b) organizing sampling programmes and measurements, (c) connecting laboratory analysis to data management, (e) using numerical and graphical methods for describing monitoring data (descriptive statistics), (f) understanding and reporting removal efficiencies, (g) recognizing symmetry and asymmetry in monitoring data (normal and log-normal distributions), (h) evaluating compliance with targets and regulatory standards for effluents and water bodies, (i) making comparisons with the monitoring data (tests of hypothesis), (j) understanding the relationship between monitoring variables (correlation and regression analysis), (k) making water and mass balances, (l) understanding the different loading rates applied to treatment units, (m) learning the principles of reaction kinetics and reactor hydraulics and (n) performing calibration and verification of models.
The major concepts are illustrated by 92 fully worked-out examples, which are supported by 75 freely-downloadable Excel spreadsheets. Each chapter concludes with a checklist for your report. If you are a student, researcher or practitioner planning to use or already using treatment plant and water quality monitoring data, then this book is for you!
ISBN: 9781780409313 (paperback)
ISBN: 9781780409320 (eBook)
ISBN: 9781780409337 (ePub)
Chapter 8: Symmetry and asymmetry in monitoring data. Normal and log-normal distributions
2020. "Symmetry and asymmetry in monitoring data. Normal and log-normal distributions", Assessment of Treatment Plant Performance and Water Quality Data: A Guide for Students, Researchers and Practitioners, Marcos von Sperling, Matthew E. Verbyla, Sílvia M. A. C. Oliveira
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This chapter presents the foundations of two of the most important frequency distributions in environmental monitoring: normal and log-normal distributions. The main characteristics, properties, and parameters are presented, with indications on how to define and interpret them. Normal distributions are widely used and are associated with a symmetric interpretation of data distribution; however, this may not be the case with environmental monitoring data. Therefore, we provide conceptual background to think about data in a nonsymmetrical way, taking the log-normal distribution to represent this typical asymmetrical behaviour of environmental data. Chapters 9 and 10 will make use of the concepts presented here.