Fundamentals of Wastewater Treatment

Abstract: the Sewer Design Guide is a guide for the engineer when planning and designing wastewater facilities and should be used for both public facilities and private facilities which serve multiple lots. This guide summarizes and outlines relevant City policies, applicable codes, and engineering and operational practices and procedures that have been developed in an effort to establish a cost-effective, reliable, and safe wastewater collection system. Also to be considered and used in conjunction with this design guide are all applicable current standard drawings, specifications, codes, laws and industry requirements for the planning and design of wastewater infrastructures

Due to water shortage, wastewater reuse has gained great importance in many parts of the world. Wastewater reuse practices have become valuable source in water resources management. As an independent source of water, reclaimed water can increase the reliability of water supply. Reclaimed wastewater requires effective measures to protect public health and the environment. Strong wastewater reuse guidelines and regulations are developed for the purpose. It is difficult to establish wastewater guidelines and regulations that can suit all regions in the world. Among the broad reasons for this as limiting factors, are economics of countries relating chosen treatment technologies and additionally, the local context of a region must be taken into consideration in settings. Almost all wastewater reuse guidelines and regulations are bacteriological-based. Some of them consider biochemical parameters. In this lesson you will comprehend the importance as well as the necessity of setting wastewater reuse guidelines and regulations. You will be aware of arising problems for getting universal valid standards. You will get an overview of guidelines and regulations existing worldwide and regionally.

Conventional wastewater treatment technologies improve the quality of wastewater discharged into the environment and restrain polluted waters from contaminating other available clean water resources. However, these treatment technologies do not make wastewater fit for further beneficial uses in communities closer to the points of generation. Innovative and advanced technologies that can further improve the quality of wastewater are needed to overcome this limitation of conventional technologies, and to promote widespread adoption of recycle and reuse practices. Advanced treatment processes can be biological processes, physicochemical processes, or a combination of both (hybrid processes). Biological processes to remove nutrient pollutants such as nitrogen and phosphorus, provide the platform for further wastewater treatment to reusable quality. Physicochemical processes such as deep-bed filtration, floating media filtration, and membrane filtration, play a major role among treatment technologies for water reuse. Membrane filtration has significant advantages over other processes since they produce high quality effluent that requires little or no disinfection with minimum sludge generation. The hybrid processes attempt to obtain the benefits of both biological and physicochemical processes in one step.

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.

The Swedish Environmental Protection Agency (EPA) has determined a need to introduce advanced treatment for pharmaceutical residues in wastewater. An additional benefit of such a treatment is that it would also include the treatment of other hazardous substances.The extent to which pharmaceutical residues risk becoming a problem depends on local conditions such as the sensitivity of the receiving waters. While this is an important variable to consider, the Swedish EPA believes that the sensitivity of the receiving waters should not be the only consideration when setting requirements for treatment. The amount of released pharmaceutical residues and long-term effects should also be considered in decision making and justification. The investment and operational costs of introducing advanced treatment depend in part on the size and current capacity of treatment facilities, which is why size limitations can be an additional consideration when setting requirements.

•Describe the activated sludge process and its control variables. •List List three types of activated sludge treatment plants.