Oil well produced liquid storage device and storage method

The invention discloses an oil well produced liquid storage device which comprises a tank body which is a horizontal storage tank; the first partition plate and the second partition plate divide the tank body into three cavities which are not communicated with each other, the first partition plate and the second partition plate move in the horizontal direction to change the volumes of the three cavities, and the three cavities are provided with a feeding port and a discharging port respectively; and the two pairs of limiting stoppers are arranged on the two sides of the first partition plate and the second partition plate correspondingly, and the positions of the two pairs of limiting stoppers can be adjusted. The invention further discloses an oil well produced liquid storage method. The device can be applied to storage of oil well produced liquid in a remote oil field, sewage, crude oil and gas separated from the oil well produced liquid can be stored at the same time by arranging the three cavities which a