Academic literature on the topic 'Storage tanks Design and construction'

The use of storage tanks in sewerage systems has increased in recent years. The primary functions of such tanks are to attenuate flow and to retain pollutants within the sewer system. The main problem is to provide storage and effective separation of gross and suspended solids without incurring poor self - cleansing and associated high maintenance costs. The size of the required storage volume is dependant on the purpose for which the tank is to be used, but the end product of any design analysis is a fixed volume of storage. This project has involved the development of fullscale and laboratory computer controlled monitoring systems for the purpose of flow visualisation and digital imaging and for the comparative assessment of the sediment removal performance of different geometric configurations of overflow and storage tank. These systems used sophisticated control procedures and the latter had the facility to generate a flow hydrograph of any shape and duration and to superimpose on this hydrograph a pollutograph of synthetic cohesive sediment of any distribution. A wide variety of tanks have been constructed, mainly rectangular in plan shape (some circular), but both online and off-line and with and without an overflow structure. The use of benching to the chamber floor and the inclusion of a dry-weather flow channel were common but not universal features.

The topic of chemical oxidative degradation in rotational molded polyethylene (high-density cross-linked) chemical (sodium hypochlorite) storage tanks is an industry problem that ranks at the top of current business issues for manufacturers of chemical storage tanks. The degradation of these tanks not only compromises the physical and mechanical properties of the tank material, but reduces the life expectancy of the tank, eventually resulting in catastrophic tank failure. Premature tank failure comes at a hefty cost. The reputation of the manufacturer is questioned often resulting in immediate loss of customer satisfaction and future business. The leaking of the chemical from the failed tank serves as a liable environmental hazard that jeopardizes the safety and welfare of its surroundings – people and environment. And the associated manufacturer of the failed tank is almost certainly responsible for the repair or replacement of the tank. All these associated problems and many more related to chemical tank failure cost this relatively small industry millions of dollars annually. The need to determine the failure mechanisms of these tanks is critically important. Such an understanding will provide industry with useful knowledge that will open the door for improvements in tank performance. There is no question that a deeper understanding of failure mechanisms will improve a tank manufacturer's reputation, increase business sales, and assure environmental safety. The addition of this knowledge will also instill consumer confidence in an industry that is considered to lack refined manufacturing processes and proven quality controls. Such advancements are keys to making rotational molding a cutting-edge, technology-driven process that prepares industry for future growth and development. The purpose of this research is to provide tested empirical data and proven expert analysis that can be utilized by companies in understanding the failure mechanisms of these tanks. The information regarding this topic was collected from various tank samples taken from Poly Processing, a leading manufacturer of rotationally molded polyethylene chemical storage tanks and producer of the examined samples, and Odyssey Manufacturing, a manufacturer of bulk sodium hypochlorite and the end user of the examined samples. In the final chapter of this research, a summary is presented of the important findings regarding the purpose of the thesis study.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 95-96).<br>The concept for a new form of pumped storage hydro is being developed within the Precision Engineering Research Group at MIT: the Ocean Renewable Energy Storage (ORES) project. Large, hollow concrete spheres are created, fitted with a reversible pump-turbine and deployed to the sea floor. Water is then allowed to flow through the turbine, into the sphere, to produce power and power is stored back in the device by running the turbine backwards as a pump and evacuating the sphere. The first prototype of that concept is presented here. A land-based system was designed, built and tested to demonstrate its ability to store energy and test the viability of the manufacturing methods planned. The device was successfully built and cycled, storing 2Wh of energy. The round-trip efficiency of the device was severely affected by the low efficiency of the scaled down rotating equipment. It was also found that casting a monolithic sphere is preferable to assembling multiple pieces and that the interior of the sphere should be maintained at atmospheric pressure via a vent line.<br>by James D. C. Meredith.<br>S.M.