Working Principle of the Hydrocyclone Separator

Hydrocyclone Separation is an efficient and energy-saving separation technology, with its key component being the Hydrocyclone Separator. Oil-containing wastewater is injected tangentially into the Hydrocyclone Separator under a certain pressure or velocity, causing it to rotate at high speed inside the Hydrocyclone Separator and generating a centrifugal force field.

Under the influence of centrifugal force, the denser water is thrown outward and moves downward along the wall, discharging as the bottom flow. The less dense oil moves toward the center and moves upward, eventually discharging as the overflow, thereby achieving the purpose of liquid separation.

The Hydrocyclone Separator consists of multiple conical tubes, with the two ends of the conical tubes fixed by two fixed baffles within a cylindrical container, separating it into three sections: the inlet chamber, outlet chamber, and oil collection chamber. In the working principle of the Hydrocyclone Separator, the oil-containing wastewater enters the head of the conical tube through the tangential inlet at the end of the inlet chamber, flowing in a high-speed spiral motion along the wall of the cone, toward the increasingly narrow outlet end (tail). The high-speed rotation generates centrifugal force, which increases as the rotation speed increases.

Due to the difference in density between oil and water in the oil-containing wastewater, a density difference exists. The less dense oil droplets are pressed toward the center by the centripetal force, the counterforce of the centrifugal force. The centrifugal force increases from the inlet to the outlet, so the centripetal force acting on the oil droplets also increases. The oil droplets in the center are pushed from the small end (outlet) to the large end (inlet). The oil is then squeezed out through the oil discharge pipe at the top of the outlet end into the oil collection chamber, separating the oil droplets from the water in the wastewater. The water flows into the outlet chamber from the small end.

The density difference between oil and water should generally be greater than 0.05 for effective oil removal using the Hydrocyclone Separator. For non-emulsified oil-containing wastewater, the Hydrocyclone Separator can achieve high-efficiency oil removal. For emulsified oil-containing wastewater, de-emulsification treatment should be performed before using the Hydrocyclone Separator for oil removal. The oil droplets separated by the Hydrocyclone Separator generally have a size of 15 μm or greater.

The Hydrocyclone Separator is widely used in crude oil dehydration, oil-containing wastewater treatment, as well as in industries such as chemical, mechanical, refining, oil ports, ships, offshore platforms, and environmental protection for oil-containing wastewater treatment and liquid-liquid separation where there is a density difference. It can also be used in series in a secondary stage for high-concentration applications.