The Water Industry has been embracing several changes arising of rapid urbanisation, severe climate changes, rising customer demands, emerging digital technologies and growing statutory compliances. These changes will present businesses with a complex set of challenges that could be worth addressing in order to stay competitive within the industry. Can such challenges be turned into opportunities that benefit businesses, customers and the environment? We think yes and we strive forward to address them through technologies that can make a lasting positive impact.
The activated sludge process is one of the most commonly used for secondary wastewater treatment. As a suspended-growth biological treatment process, activated sludge utilizes a dense microbial culture in suspension to biodegrade organic material under aerobic conditions and form a biological floc for solid separation in the settling units. Diffused or mechanical aeration maintains the aerobic environment in the reactor. Typical retention times are 5-14 hours in conventional units rising to 24-72 in low rate systems (Gray, 1999).
The sequencing batch reactor (SBR) is a fill-and- draw activated sludge system for wastewater treatment. In this system, wastewater is added to a single “batch” reactor, treated to remove undesirable components, and then discharged. Equalization, aeration, and clarification can all be achieved using a single batch reactor. To optimize the performance of the system, two or more batch reactors are used in a predetermined sequence of operations. SBR systems have been successfully used to treat both municipal and industrial wastewater. They are uniquely suited for wastewater treatment applications characterized by low or intermittent flow conditions.
The Extended Aeration Process, a modification of the Activated Sludge Process, effectively treats the contaminants in wastewater. The standard basis of design includes an aeration system, providing a 24-hour detention time and a final settling tank, with an effective 4-hour detention time. Diffused air is introduced into the aeration tank, this provides the proper environment for the development of aerobic bacteria. These bacteria thrive on the materials contained in the wastewater. The prolonged period of aeration, in addition, oxidizes a portion of the solids in the system. Oxygenation by diffused aeration provides operating flexibility and standby reserve to meet the demanding requirements of varied package plant applications
The upflow anaerobic sludge blanket (UASB) reactor has been recognized as an important wastewater treatment technology among anaerobic treatment methods. The merits are performance, green energy generation, minimal space requirement, and low capital, operation, and maintenance costs.