The tank-group extraction unit is a type of equipment used for oil extraction in early and current domestic small-scale extraction oil factories.

This Hongyang extraction unit is a cylindrical container with a disc-shaped head. At the bottom of the cylindrical tank, there is a false bottom made of two layers of 8mm diameter perforated screens, with hemp bags or palm fiber in between. The false bottom is tightly mounted on a lower grated iron frame to withstand the weight of the material and solvent, as well as the steam pressure during the "downward pressure" operation (usually around 98kPa). After the false bottom is installed, only liquids like mixed oil and solvent can pass through, while meal particles cannot. The top cover is equipped with an inlet pipe, and there is an outlet for meal at the tank body, with various pipes for operation mounted on the shell.

The characteristics of tank-group extraction are simple equipment, low investment, small solvent consumption and energy consumption, strong adaptability to various oil materials, and suitable for small-scale enterprises producing multiple varieties in small batches.

Attentions during the operation of the tank-group extractor:

1. First, the pre-pressed cake is conveyed by a screw conveyor into the extraction workshop and lifted by a bucket elevator to the overhead auger. Then it enters an inclined storage bin or directly enters the Hongyang extraction tank to shorten the loading time of the extraction tank.

2. Open the top cover of the extraction tank, fill it with material until full, and then seal and tighten the top cover.

3. Start to introduce fresh solvent, first open the solvent pump and valves to draw from the solvent circulation tank, open the steam valve to heat the solvent in the preheater. When the solvent temperature reaches 45-50°C, it is then pumped through the spray pipe into the Hongyang extraction tank until it is full. (The solvent should be 20-50mm above the cake surface) Open the free gas valve for normal immersion.

4. Immersion time is 10-15 minutes. Turn on the mixed oil pump to collect from the tank below the Hongyang oil extraction tank and pump it into the tank for circulation for 5 minutes or directly pump it into Tank 2 until it is full with solvent oil. If the solvent oil is insufficient, add fresh solvent oil.

5. Immersion time in Tank 2 is 15-20 minutes, pump the mixed oil into Tank 3 for immersion, immersion time is 10-15 minutes, then pump the mixed oil into Tank 4 for immersion for 10 minutes. The mixed oil is circulated 3-4 times. If the concentration of the mixed oil is not enough, it can be pumped into the mixed oil temporary storage tank for circulation.

6. The mixed oil collected in the tank below the extraction tank is pumped through the filter into the mixed oil temporary storage tank for settling. At the same time, 6oBe' brine is pumped from the brine tank into the mixed oil temporary storage tank to precipitate fine debris.