Clear-waste tank

Clear-waste tank. An unlined steel clear-waste tank is typically used to hold clarified waste before injection. The tank is equipped with a float switch designed to start and stop the injection pump at predetermined levels. 

Numerous °Sr and Cs plumes apparently emanate from leaks in high-level waste tanks at Hanford. Typically the tanks contain waste sludges and residual caustic solutions. Movement of Sr and Cs through the vadose zone beneath the tanks might have been aided by direct and indirect action of the caustic solutions on aqueous spcciation and the surface reactivity of otherwise sorptive phases that exist at depth. C olloidal transport probably also plays a role in contaminant transport. A recently initialed vadose /one monitoring effort will ho icfiilly provide a clear pic-... 

Continuous clarifiers generally are employed with dilute suspensions, principally industrial process streams and domestic municipal wastes, and their primary purpose is to produce a relatively clear overflow. They are basically identical to thickeners in design and layout except that they employ a mechanism of hghter construction and a drive head with a lower torque capability. These differences are permitted in clarification applications because the thickened pulp produced is smaller in volume and appreciably lower in suspended solids concentration, owing in part to the large percentage of relatively fine (smaller than 10 Im) solids. The installed cost of a clarifier, therefore, is approximately 5 to 10 percent less than that of a thickener of equal tank size, as given in Fig. 18-94. 

Waste Reduction Processes can be redesigned to reduce the amount of waste generated. For example, transfer hnes between processes can be Blown clear pneumaticaUy to drive liquid into the Batch mix tank. 

All tanks shall have level indicators, which are clearly visible from a distance, and low-level alarms. The overflow nozzles/Unes from the tanks shall be connected to a header (which is then connected to another collection tank) so that no water is wasted at any time (water meters, flow indicators, and quantity totalisers shall also be provided to measiu e the quantities received into and consumed from important tanks). 

Volume reduction of concentrated evaporator bottoms, which may include boric acid wastes, laundry wastes, chemical wastes, and other floor drain wastes, is accomplished in the radwaste volume reduction system. The major components of the system are the crystallizer chamber and recirculation system, condenser, and vacuum pump system. The crystallizer chamber consists of a conical tank and an inner circular baffle to separate solid crystals from a clear recycle stream. Combustible wastes such as clothing, filter cartridges, and wood are volume-reduced in the radwaste incinerator. Solidification of volume-reduced wastes and other low-level radioactive wastes, such as spent resins and contaminated tools, is performed in the cement solidification system. The major components of the cement solidification system include the high shear radwaste mixer, waste dispensing system, flush water recycle steam, cement storage and feed system, and the container handling system. 

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