Water & Wastewater Asia Jan/Feb 2018

WATER & WASTEWATER ASIA January / February 2018 periodic inspections to check on the safety and soundness of the pits are required by the Japanese law. Since emptying the pits to check for abnormalities such as cracks and damage is difficult, TFC carries out regular “water logging” inspections. During these inspections, the pits are filled with water and left for some time, after which any decrease in the water level is measured using a level gauge and recorder. Level measurement is simply about determining the position of a surface inside a tank. To be more precise, it is the determination of the linear vertical distance between a reference point – usually the base of a holding container – and the surface of a liquid, the top of a solid, or the interface of two liquids. Precise handling of the level of liquid in a tank is important in process control, inventory management and custody transfer. In the case for TFC, process control was needed tomaintain environmental protection and compliance. During TFC’s inspections, some elements of the wastewater treatment process needed to be stopped completely, which delayed production. Therefore, it is vital to carry out the inspection as quickly as possible so as not to incur more costs or sacrifice accuracy. The Rosemount™ 3308 Wireless Guided Wave Radar installed over the concrete pit