Rotating Biological Contactors (Biodiscs)

The content of this technical sheet on “aerated ponds” is based primarily on the following publications: “Aerated Pond”, compiled by Eawag (Swiss Federal Institute of Aquatic Science and Technology), Dorothee Spuhler (international Gmbh) published on SSWM (http://www.sswm.info) (2015). “Aerated, partial mix lagoons”, Technology Fact Sheet 832-F-02-008, published by U.S. EPA (2002). “Principles of design and operations of wastewater treatment pond systems for plant operators, engineers, and managers”, EPA/600/R-11/088, published by U.S. EPA (August 2011).

• Identify the source and general types of wastewater odors. • List three potential impacts of odors. • List three factors affecting the existence of odors. • Name a commonly used method to reduce odors from wastewater. • Describe three methods for solving odor problems in air.

This book provides an overview of the most studied AOPs, some of which are largely implemented for water remediation. The fundamental principles, kinetic modeling, water quality impact on process performance, byproduct formation, economics, examples of research and pilot studies, full-scale applications and future research needs are discussed for each advanced oxidation process.

Over the last few decades adsorption has gained paramount importance in industry and environmental protection. Adsorption processes are widely applied for separation and purification because of the high reliability, energy efficiency, design flexibility, technological maturity and the ability to regenerate the exhausted adsorbent. One method of important extending the adsorption treatment processes is biofiltration. The biological filter relies on the activities of the community of micro-organisms that become attached onto the filter media. Microbes oxidize organic matters in water to produce energy and therefore available nutrients sources in feed water are essential for their development. Biofiltration can effectively remove organic matter that is not able to be removed from water and biologically treated sewage effluent in conventional sewage treatment. The microbial attachment process, the factors that influence biological filtration, the kinetics of microbial growth and details of the microbial community in the biofilter are discussed in detail. There are several types of biofilters including submerged filters, trickling filter, bed filter, fluidised bed. The different biofilters are described and a comparison between them is provided. The application of biofilters for treating various types of wastewater effluent is detailed.

Introduction Every year in South Africa an estimated R500m is spent on chemicals used in the treatment of drinking and waste water. Most of this money is allocated on the basis of tenders issued and contracts awarded. The evaluation of tenders is generally undertaken by a team of people from various disciplines within the awarding organization and the decisions they make can have a significant effect on the quality of water or waste that is produced and also on the finances of the organization for which they work. It is obvious therefore that these decisions – which chemicals to use, how much to use, how much should be paid, who is the most professional supplier – are important ones and ones that should be taken whilst in possession of the most factual and impartial information. This guide aims to provide those decision-makers, and other users of water treatment chemicals, with specific and useful information about water treatment chemicals. It is a chemistry text book aimed specifically at those people who have to make informed decisions but who have not had a formal education in chemistry or whose chemistry education has not been specific in detail relevant to water treatment chemicals. It does not, however, aim to be a comprehensive chemistry textbook and chemicals not used in water treatment are not discussed; nor are properties that are irrelevant to the water treatment application of the chemical. The guide is designed to serve as a reference book with each chapter being self contained and specific. It will be easily understood by those readers that do not have a formal chemistry education and hopefully will provide some useful additional insight and information to those that The guide is divided into ten chapters and includes an appendix at the end that contains various useful equations. The contents of each chapter are listed below.