The oil separation tank utilizes the different specific gravity of suspended solids and water in wastewater to achieve separation. The structure of oil separation tanks often adopts a laminar flow type. Oil containing wastewater enters the rectangular oil separation tank through a water distribution tank and flows slowly in the horizontal direction. During the flow, the oil product floats on the water surface and is pushed into the oil collection tank by the oil collection pipe or a scraper set on the tank surface and flows into the dehydration tank. The heavy oil and other impurities that settle in the oil separation tank accumulate in the sludge hopper at the bottom of the tank and enter the sludge pipe through the discharge pipe. The wastewater treated with oil separation overflows into the drainage channel and is discharged outside the pool for subsequent treatment to remove emulsified oil and other pollutants
Processing principle
The basic principle of using oil separators and sedimentation tanks to treat wastewater is the same, both of which use the different specific gravity of suspended solids and water in the wastewater to achieve separation. The structure of oil separation tanks often adopts a laminar flow type. Oil containing wastewater enters the rectangular oil separation tank through a water distribution tank and flows slowly in the horizontal direction. During the flow, the oil product floats on the water surface and is pushed into the oil collection tank by the oil collection pipe or a scraper set on the tank surface and flows into the dehydration tank. The heavy oil and other impurities that settle in the oil separation tank accumulate in the sludge hopper at the bottom of the tank and enter the sludge pipe through the discharge pipe.
Oil separators are often constructed with reinforced concrete or with bricks and stones. They are divided into 2-4 grids along the direction of water flow on a rectangular plane, with each grid generally not exceeding 6 meters in width, to ensure even water distribution. The effective water depth does not exceed 2 meters, and the length of the oil separation tank is generally more than 4 times the width of each compartment. Chain belt oil scraper and mud scraper are commonly used in oil separation tanks to scrape off floating oil and bottom sludge, respectively. Generally, each grid is equipped with a set of oil scraper and mud scraper, and a sludge hopper is set up. If a baffle is added in the middle of each grid, and oil and mud scrapers are installed on both sides of the baffle, and a sludge hopper is installed, it is called a two-stage oil separator (see figure [two-stage oil separator]), which can improve the oil removal efficiency, but with more equipment, energy consumption increases. If several inclined plates are added to the oil separation tank, the oil removal efficiency can also be improved, but the construction investment is relatively high. In cold regions, to prevent oil solidification in winter, a steam pipe can be installed at the bottom of the oil collection pipe for heating. Oil separators generally need to be covered and steam pipes should be placed under the cover plate for insulation, to prevent fires and oil evaporation in the oil separator, and to prevent dust and sand from entering.
Installation instructions
The oil separation tank product needs to be directly installed on the channel containing sewage and oil-water flow. Align the sewage outlet with the inlet of the oil-water separator with a grid, and connect it with other equipment through pipelines.
The oil-water separator (oil separator) must be adjusted to a horizontal position during installation.
Before the first use, the equipment should be filled with tap water, and the water level adjustment pipe should be adjusted so that the top of the water level adjustment pipe is at the same level as the upper edge of the overflow tank. The position of the inlet pipe should be kept at a certain distance from the debris separation box to facilitate the removal of the debris separation box.
Introduce oily wastewater and adjust the water level control pipe again until the oil drain pipe only drains oil without draining water.
If the position of the oil discharge pipe is too low, the equipment cover can be opened and the oil can be removed with tools.
design basis
1. The oily wastewater from canteens and restaurants should be discharged into the sewage pipeline after passing through the oil removal device.
2. The sewage flow rate should be calculated based on the design second flow rate.
3. The flow velocity of sewage containing edible oil in the pool shall not exceed 0.005m/s.
4. The retention time of wastewater containing edible oil in the pool water is 2-10 minutes.
5. The volume of oil stored in the oil separation tank for manual oil removal shall not be less than 25% of the effective volume of the tank.
6. The oil separation tank should be equipped with a movable cover plate. The inlet pipe should consider the possibility of being clear and unobstructed.