Vacuum Pump Paper Industry

Vacuum pump is a common vacuum equipment in paper mill equipment. The commonly used type is 2SK liquid ring vacuum pump, but 2SK liquid ring vacuum pump, which consumes high energy and has low efficiency. It is an old type. The 2BV liquid ring vacuum pump or 2be liquid ring vacuum pump produced by EVP vacuum pump manufacturer is a kind of vacuum pump with high cost performance, low energy consumption and high efficiency. At present, 2BV liquid ring vacuum pump or 2BE liquid ring vacuum pump are used in most large papermaking plants.

vacuum pump in paper industry is as follows:

Liquid ring vacuum pump for black liquor evaporation

Black liquor evaporator in pulp mill is used to concentrate black liquor produced in pulp cleaning process so that these liquids can be recovered in the recovery furnace and reused in pulp production.

liquid ring vacuum pump used in crude pulp washer

Prior to bleaching or other raw material preparation, the pulp washer removes Pulp Chemicals (“black liquor”) from paper-making raw materials. Rough pulp washer is a typical horizontal drum filter. The drum-shaped cavity can produce vacuum. When the drum rotates in the raw material pulp, vacuum can make the raw material adhere to the outer surface of the drum and help remove (clean) black liquor from the raw material.

Liquid ring vacuum pump for lime slurry and filter

Lime slurry filters in pulp mills are used to recover lime during white water clarification. Similar to the crude pulp washer, the lime mud filter is a typical horizontal drum filter. Vacuum can be generated inside the drum. When the drum rotates in the lime mud, a lime cake forms on the outer surface of the drum. Then scrape it off and reuse it in whitewater process.

Liquid Ring Vacuum Pump for Precipitate Filter

Precipitate filters in pulp mills are used to filter unburned suspended particles in “green liquor”, remove carbon particles for full combustion, iron compounds and insoluble furnace debris prior to denaturation. The sediment filter is a typical horizontal drum filter. A vacuum can be created inside the drum to extract particles from green liquor.

liquid ring vacuum pump for vacuum dehydrator

The dehydrator is used to dehydrate the raw material in the preparation stage to increase the concentration of the raw material. The dehydrator is a typical horizontal drum filter, which is used to dehydrate pulp proportionally to increase the concentration of raw materials.

Liquid Ring Vacuum Pump for Raw Material and White Water Degassing System

Raw materials and white water degassing system are used in the preparation stage of raw materials to remove air carried by raw materials or air from diluted water before entering the mixing box. Material and white water degassing systems are very important because air is removed from paper-making raw materials, which can lead to pinholes on paper, and greatly affect the printing quality, mechanical properties and overall quality.

This degassing system is a typical two-stage vacuum system: the boiling point of raw materials at the inlet of the first vacuum pump (27-28 in. HgV), and the compression ratio of the inlet pressure of the second vacuum pump (4:1). The pre-condenser is typically used between the degassing vessel and the first vacuum pump, and a small inter-stage separator is required between the two vacuum pumps. Vacuum pumps are made of standard materials.

Liquid ring vacuum pump for headbox compressor

The mixing box compressor/vacuum pump is applied in the “air cushion” mixing box to produce a pressure/vacuum above the raw material level (or “raw material pool”) of the mixing box to maximize the control of the raw material discharge speed (“injection” speed).

Vacuum pumps are usually used as vacuum pumps and compressors through a series of valves. Vacuum or pressure is generated in the void volume above the “raw material pool”, which is used to control the static head of the mixing box.

Liquid ring vacuum pump for suction tank

The suction tank is a static device, which dehydrates directly from the pulp on the forming section of the paper machine. There are usually 2-10 suction tanks on paper machines, usually connected into a main pipe. Because of the large amount of dehydration, it is necessary to install a pre-separator between the suction tank and the vacuum box. The liquid ring pump is used to generate vacuum in the suction tank vacuum box.

liquid ring vacuum pump for rollers

In many cases, the roller is the last vacuum point on the forming section, which is called the most important dehydration part of the paper machine. The dryness of paper affects the dehydration performance and steam consumption of the press section when the roll is released and enters the press section.

The couch rollers are stationary, with rotating holes in the housing. The roller can have one or two vacuum areas.

Suction roll and transfer roll

The suction roller sucks the paper away from the mesh on the forming step and leads it into the pressing section. Then, in the press section, the transfer roll transfers the paper from one wool cloth to another. These processes are not formally dehydrated, but a small amount of water can be removed from the paper.

Liquid Ring Vacuum Pump for Vacuum Compression

Vacuum press uses mechanical method to extract water from paper. In the pressing section, the rollers with granite and hard rubber surfaces are closely contacted to form a “pressing zone”. Typical paper machines may have 1-3 “pressing zones”. When the paper passes through the pressing area, the water is squeezed out and seeps into the pressed wool cloth, which is used as the transportation tool and cushion of the paper when the paper passes through the pressed part. In the process of dehydration, there are vacuum and non-vacuum rollers in the pressing section.

Liquid ring vacuum pump for wool suction tank

When the pressing part is pressed, the pressed fabric (or “wool”) contains a mixture of water, chemical materials, paper-making materials, clay and fillers, sticky residues (“asphalt”) produced in the paper-making process and glue (“sticky”) produced by recycled paper. Since each piece of wool is a continuous cycle, moisture and contaminants must be removed before the next press begins. The vacuum suction tank is a fixed suction tank, which exceeds the width of the wool cloth and absorbs the water and pollutants accumulated during the pressing process. Each piece of wool has two vacuum suction tanks.

When using vacuum suction tank, it must be pre-separated to avoid carrying water into the vacuum pump.

Liquid ring vacuum pump for blowout preventer

In the press section, there are some “open” press zones, which do not support the paper before entering the press zone. Air flow may cause the paper to shake, fold or break. Blow-proof boxes are fixed and are used to generate upstream vacuum in the pressing zone before paper enters. Because the blowout-proof box cloth is used for dehydration, there is no need for pre-separation treatment.

Generally speaking, the standard pumping capacity stipulated in the paper production line is certain, but in order to reduce energy consumption and save production costs, the selection of vacuum pump is particularly important. For the paper industry, the economic benefit of liquid ring vacuum pump is the preferred vacuum equipment for paper mills.

2BE1 Series Liquid Ring Vacuum Pump

2BV Series Liquid Ring Vacuum Pump