Although developments in wastewater treatment over recent decades have focused on the biological reactor, the secondary settling tank (SST) also plays a major role in achieving increasingly stringent effluent quality standards. This report collates many of the significant developments that have taken place in SST theory, design, modelling and operation. Earlier SSTs were designed only by empirical hydraulic criteria such as overflow rate, which do not recognize sludge concentration and settleability. Today, there are available not only much improved design procedures but also hydrodynamic models for simulating water and solids distribution and flows in full-scale SSTs. Nine chapters cover a wide range of subjects including: Flocculation and settling behaviour of biological sludges SST performance evaluation protocols Development and evaluation of the different design procedures such as the flux theory and the ATV design rules Developments in and application of one- two- and three-dimensional modelling Experience-based aspects of design and operation of circular, rectangular and vertical SSTs. Reprinted for 2006 Scientific and Technical Report No.6
What is the role of elites in shaping foreign policy? Did unaccountable foreign policy elites shape the post-1945 world order? Chatham House and the Council on Foreign Relations were vital in America's shift from isolationism to globalism, and in Britain's shift from Empire to its current pro-American orientation and were also fundamental in engineering public backing for a new world order. Inderjeet Parmar presents new evidence to show how well-organized and well-connected elite think tanks helped to change the world.
A guide to the entire process of installing and managing underground storage tanks, with a focus on preventing leaks, and what to do if a leak occurs.