About Pressure Leaf Filters and their usage

In order to carry out an efficient oil filtering process, the use of technologically advanced machines is of high importance. One of the most popular filtering machine is the Pressure Leaf Filters which are of two types; Vertical Pressure Leaf Filters and Horizontal Pressure Leaf Filters. These filters consists of vertical vessels and horizontal vessels respectively. These filters also consists of filter leaves that are made up of several layers of wire mesh. The inner mesh is for discharging filtrate and also to support the outer layers.

About Vertical Pressure Leaf Filters

In a Vertical Pressure Leaf Filter, the slurries or mixtures are pumped into the vessel with the use of pressure. The vessel is fitted with vertical leaves that serve the purpose of the filter. Each leaf has a centrally located neck at its bottom and collects the filtrate. The leaf is constructed in such a way with ribs on both sides, which allows the filtrate to flow freely towards the neck. The leaf is also covered with coarse mesh screens that support the fine woven filter cloth that retains the cake. The space between the leaves vary in size depending on the formation of the cake and also the ability of the vacuum to hold the cake to the vertical leaf surface. The filtered cake is then dried and is discharged with the help of a pneumatic vibrator through the cake discharging outlet. The wet cakes are discharged through the small opening and the dry cakes are let out through the larger opening.

A large variety of Vertical Pressure Leaf Filters are available in today's market, which meet the varied requirements of the oil filtering companies all over the world. Manufacturers are making all possible use of the available technology in order to come up with the most innovative and well fabricated oil milling equipment.

Features of Vertical Pressure Leaf Filters

• Available in various sizes and capacities at the most cost-effective prices.

• Easy discharge of cakes as gravity releases the cake and lets it drop towards the discharging outlet.

• Are used when there is a need for large filtration without the use of much flooring space.

• The filter cloth or woven mesh screens are easily accessible.

• Simple mechanism as there are no complex bearing or sealing glands.

About Horizontal Pressure Leaf Filters

Apart from Vertical Pressure Leaf Filters, another type of filtering machine is known as Horizontal Pressure Leaf Filter. This type of machine is highly standardized and well designed to meet the varied requirements of the oil milling companies. This machine has continuously proved its mettle and renowned as an user-friendly and eco-friendly equipment. Filtering equipment are used to separate or filter all kinds of liquid from impure and unwanted particles that are present in the liquids. Likewise, horizontal pressure leaf filters are used for oil filtration purpose, and to separate the filtrate and filtered cake, and filtration of slurry from the liquids. These are also mainly used in when the filter cakes are sticky and difficult to remove. The cover of this equipment can also be pulled out to enable the easy discharge of the leaves for cleaning.

This type of Filter consists of a stack of plates that are attached to a hollow shaft, which further mounted inside a pressure vessel. Each of this plate is covered with a suitable filter medium. Every plate is circular in shape and has radial ribs that are welded to the bottom and also supports a horizontal coarse mesh screen which is covered with a finer woven metal screen or filter cloth which is used to retain the cake. The bottom of the plate slopes towards the hollow central shaft, which lets the filtrate flow freely through circumferential holes and further down the shaft towards the filtrate discharging outlet.

The Horizontal Pressure Leaf Filter also consists of vessels and are constructed vertically to accommodate the plates stack. The bottom design for this type of machines are available in two types namely Conical Bottom and Dished Bottom. The vessels at the bottom have secure cake discharge outlets, which ensures the safe sealing of the tank even under pressure. The tanks which have a conical bottom discharge the cake by gravity, and the tanks with dished bottoms consist of a spade that rakes and transports the cake towards the outlet. Because of this reason, the conical bottoms require more headroom than the dished bottom having the same filtration capacity.

The slurry or mixture is put into the vessel through the opening with the help of pressure. The cake which is retained by the filter medium forms on top of each plate while the filtrate passes through the hollow shaft. The cake is then dried and with the use of pressure, the plate stack are rotated and thus, the cake is released through the cake discharge outlet. The cake outlet interlocks after the discharge with a motor drive as the rotating is continuous.

A wide range of high quality and technologically advanced horizontal pressure leaf filters that are available in the Indian as well as global market today. These are fabricated to give a compact and sturdy construction.

Features of Horizontal Pressure Leaf Filters

• High productivity due to the high rate of filtration.

• Highly user-friendly

• Economical operational costs.

• Compact operation and thus no spillage.

• Available in large capacities and various sizes.

• Requires minimum floor spacing.