MODERNIZATION OF BOTTOM SEDIMENT SCOURING PROCESS IN RVSP 20000 TANKS

Abstract

According to the existing norms a tank should be necessarily taken out of operation once in 8-10 years for diagnostic works. The most labor-intensive part is removal of paraffin deposits from its bottom. In this regard, the main purpose of the study is to study the technology of the process of scouring bottom sediments in steel vertical cylindrical tanks with a pontoon volume of 20000 m3 (RVSP 20000) and modeling the operation of various cleaning devices to determine the most effective of them.
 The RVSP 20000 tank includes a device for bottom sediment scouring «DIOGEN-700». In the process of its operation under the action of the rotating blade of the propeller a jet of liquid is created, which mixes oil in the tank due to circular movement of streams. The greatest ac- cumulation of paraffin trace is observed in the-near-wall zone of the tank, therefore there is a need to find a new method of hydromechanical prevention of sludge accumulation on the bottoms of oil tanks.
 As the main device for bottom cleaning it is proposed to use a stirring jet device («UPS-EVNAT»). It divides one main stream into several equal parts. As a result, the area of sediment scouring is higher than when using standard equipment.
 In this work, the turbulent string flow with the use of screw agitator «DIOGEN-700» and with the use of «UPS-EVNAT» was modeled. The revealed results allow to assert that the application of agitating jet device allows to realize better quality erosion of paraffin deposits and cover a larger area in comparison with «DIOGEN-700».