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4. Cleaning vessels and reservoirs by MegaMacs (Heating Oil holdings) The process works much the same way whether cleaning tank bottoms, processing drummed sludge or cleaning up a lagoon or separator pond. Depending on product stored and local conditions different cleaning agents are used. When sludge already contains some water (crude oil application), it is practical to use water as a cleaning agent. In this case three phase centrifuge unit will be beneficial which will: produce sellable oil byproduct, reduce water consumption and separate vast majority of solid phase. Should cleaning of refineries or power plants tanks required, cutter stock should be used as a cleaning agent. This will allow not only increase extraction of hydrocarbons but also reduce heavy hydrocarbons content in solid phase due to their high solubility in the hot cutter stock. In this case centrifuge is not as practical. Finer screen on vibro separator maybe used instead. Byproduct received has parameters of regular heating oil which could be sold or returned to refining process. Following is a description of technological process with a cutter stock used as a cleaning solution. Main process tank filled with 10-15 m3 of cutter stock and heated to 180°F (82°C) by recirculation through heat exchanger using washing pump. Robotic Cannon on a tripod and booster pump are installed inside the tank against each other. Hydraulic and process hoses network connected. As soon as everything connected and cutter stock is heated, wash pump switched to cleaning mode and delivers hot cleaning/diluting agent to Robotic Cannon. After pressurized hot stream from cannon dilutes sludge it extracted from the tank by booster pump. 4.1. Recirculation System From booster pump diluted sludge goes directly to vibro separator where solid particles (up to 2 mm) are removed. Remaining mix enters MegaMacs’ main process tank where solid particles (less than 2 mm) settle to the bottom and light fraction rises to the top of the tank. Settled solids are removed by helical conveyor and solid’s pump. Floating skimmer with pump evacuates light fraction for further processing. Cleaning/diluting agent returned to the robotic cannon, through heat exchanger, closing the loop. Some quantity of cutter stock has to be added periodically. Recirculation continues until bottom sludge is completely removed from the tank. Once this is done operators replace robotic cannon with wash heads installed on tripods evenly spreading them across the tank. After wash heads are connected, hot cleaning solution is drown to them by wash pump and process is restarted. Should change of holding product or welding repairs are planned, tank might be washed with water (caustic may be added) using same wash heads. On a final stage after wash heads are removed high pressure hand guns with water are used for detail cleaning in hard to reach places. As soon as cleaning finished, reservoir allowed to naturally drying out. Such system requires 3 operators per working shift.  |