The structure and working principle of the van filter press

Van filter press is a kind of intermittent pressure filter equipment, used for all kinds of suspension of solid-liquid separation, separation effect is good, easy to use, widely used in petroleum, chemical, dye, metallurgy, pharmaceutical, food, paper, coal washing and sewage treatment and other industries that need to carry out solid-liquid separation.

Hydraulic box filter press is mainly composed of four parts, namely: frame part, filter part, hydraulic and electrical control part. When the van filter press works, the piston in the cylinder body pushes the pressing plate, and the filter plate and filter medium (press cloth) are located between the pressing plate and the thrust plate, so as to ensure that the filtered material (slurry) with working pressure is pressed and filtered in the filter chamber of the press filter.

Principle of hydraulic van filter press:

The hydraulic pressing mechanism of the van filter press consists of a hydraulic station, an oil cylinder, a piston, a piston rod, and a piston rod connected with the pressure plate of Havland card hydraulic station structure consists of a motor, oil pump, relief valve (regulating pressure) reversing valve, pressure gauge, oil circuit, oil tank.

When hydraulic pressure is pressed mechanically, the hydraulic station provides high pressure oil, and the component cavity composed of the cylinder and piston is filled with oil. When the pressure is greater than the friction resistance of the pressing plate running, the pressing plate slowly presses the filter plate. When the pressing force reaches the pressure value set by the relief valve (shown by the pressure gauge pointer), the filter plate, filter frame (plate frame type) or filter plate (van type) is pressed, and the relief valve begins to unload. At this time, cut off the motor power supply, the pressing action is completed, back, reversing valve, pressure oil into the rod chamber of the cylinder, when the oil pressure can overcome the friction resistance of the pressing plate, the pressing plate began to return.

Hydraulic pressure filter press for automatic pressure preservation, the pressure force is controlled by the electric contact pressure gauge, the upper and lower limit of the pressure gauge pointer set in the process requirements, when the pressure force reaches the upper limit of the pressure gauge, the power supply is cut off, the oil pump stops power supply, because the oil system may produce internal leakage and external leakage caused by the pressure force decline, when reduced to the lower limit of the pressure gauge pointer, When the power supply is connected, the oil pump starts to supply oil. When the pressure reaches the upper limit, the power supply is cut off and the oil pump stops supplying oil. In this way, the effect of compression force is ensured in the process of filtering materials.

Filtration mode: filtrate outflow mode is divided into flow filtration and dark flow filtration. Open flow filtration, each filter plate below the liquid outlet hole is equipped with a water nozzle, filtrate intuitively from the water nozzle outflow. Dark flow filtration, each filter plate is provided with a liquid outlet hole, a number of filter plate liquid outlet hole into a liquid outlet channel, by the thrust plate under the liquid outlet hole connected with the pipeline discharge.

Washing mode: When the filter cake needs washing, sometimes flow one-way washing and two-way washing, underflow one-way washing and two-way washing. In the open-flow one-way washing, the lotion enters the hole from the thrust plate in turn, wears the filter cloth and then wears the filter cake, and flows out from the non-porous filter plate. At this time, the outlet water nozzle of the perforated plate is closed, while the outlet water nozzle of the non-porous plate is open. Open flow two-way washing is that the lotion is washed twice from the two sides of the thrust plate above the lotion into the hole, that is, the lotion is washed from one side and then from the other side. The outlet of the lotion is the same diagonal direction, so it is also called two-way cross washing. Dark current one-way flow polyester is, the lotion from the thrust plate into the hole into the hole plate in turn, through the filter cloth and then through the filter cake, from the non-porous filter plate outflow. Dark flow two-way washing is washing liquid from the two sides of the stop plate above the two sides of the wash into the hole has two times, that is, washing first from one side, then from the other side of the wash, the outlet is diagonal direction, so it is also called dark flow two-way cross washing.