Multi-plate vacuum filter application

Multi-plate vacuum filter application
Core tips: Application of multi-disc vacuum filter in the application of multi-plate vacuum filter and Shi Bao Wang Yanchang 2 (1. Henan Light Industry School, Zhengzhou 450005, Henan, China; 2. China Light Industry Machinery Corporation Anyang Machinery Plant, Henan Anyang 455000) In recent years, caused by resources and environmental problems

Application of multi-disc vacuum filter in the application of multi-plate vacuum filter and Shi Bao Wang Yanchang 2 (1. Henan Light Industry School, Zhengzhou 450005, China; 2. Anyang Machinery Plant of China National Light Industry Machinery Corporation, Anyang, Henan 455000, China) In recent years, resources and environmental issues have caused widespread concern, especially for papermaking companies, which are related to the survival of enterprises. Implementing closed water can not only save water resources, recover fillers and fibers, reduce production costs, but also reduce environmental pollution. The multi-disc vacuum filter is characterized by its large amount of processing, simple operation and low energy consumption and can be used not only for the recovery of white water or other aspects of water treatment, but also as a thickening device for slurry in the pulping and papermaking process. .

discharge. (2) The main shaft continues to rotate and the sector plate enters the vacuum filtration zone. The liquid in the tank passes through the filter and forms a filter cake. In the initial stage of vacuum filtration, the filter cake is thin, and some fine fibers and fillers pass through the filter with the filtrate to form a turbidity filtrate. As the filter cake is continuously thickened, fine fibers and fillers are blocked by the filter cake, and a clear filtrate is formed. The turbid and clear filtrates flow through the two water legs to the clear and filthy filtrate baths, respectively. (3) When the fan-shaped plate is turned out of the liquid surface, the vacuum does not disappear immediately, and the filter layer on the filter is still dehydrated, and the concentration continuously increases. (4) The main shaft continues to rotate, and the vacuum action disappears. The structure and working principle of the fan 1 The multi-disc vacuum filter is mainly composed of a tank body, a main shaft, a filter plate, a distribution valve, a stripping device, a flushing device, a washing device, and a transmission device. , discharge device and other parts. In the treatment of white water under the paper machine network, it uses vacuum as the power for filtration to recover fibers and fillers.

(1) When the main shaft rotates counterclockwise to drive the filter plate to rotate below the liquid surface, the sector plate enters the atmospheric filtration zone, the liquid in the tank body under the static pressure, passes through the filter through the main shaft and the distribution valve atmospheric filtration zone filtrate outlet shape The plate enters the stripping zone. At this time, the fan-shaped water sprayed by the detaching nozzles on both sides of the filter plate directly peels the filter layer into the hopper and is diluted by the flush pipe to discharge to the discharge device. (5) When the filter disk rotates to wash the net area, wash the net with water by the swinging wash net nozzle, restore the filter capacity and then enter the next filter cycle.

With the continuous rotation of the filter plate, the sector plates are in different sections, continuously converting white water into clear filtrate and recovering fine fibers and fillers.

2 Process Flow and White Water Recovery Process Process Flow Table 1 Process Conditions Indicator Result Remarks White Water Concentration/% Longer fiber in the initial stage of filtration helps to improve the filtration efficiency Vacuum degree / MPa filter layer sizing concentration / filter plate sizing thickness / mm peeled water Pressure/MPa Stripping water consumption 90~110m3/h Washing net water spray pressure/MPa Spraying net washing water consumption 220260m3/h Fiber recovery/Rotating disc rotation/rpm Treatment white water capacity/m3m processing capacity and filter disc rotation Relevant to the area of ​​the filter disk Table 2 Effect of use mg/L Clearance Solids Solids Turbidity Filtrate Solids Chemical oxygen demand Biological oxygen demand content ss 3 Operation and precautions Operation of multi-disk vacuum filter 3.1.1 Inspection before start-up Whether the electrical appliances and automatic control instruments are normal, whether there are foreign matters in the tank, whether there are leaks (leakage, air leakage) everywhere in the pipelines and equipment, the clear liquid pool should be filled with clean water and whether the liquid level in other tanks is normal, and the filter tray and the slurry Whether the board clearance is appropriate or not.

3.1.2 start the program to start the control instrument, check the liquid level lower limit alarm indicator is bright; the filter plate motor to 'manual' file, and start the motor to make the motor speed from 0 to 1rpm; start peeling or washing net pump, Observe whether the pulping and washing net water is running normally. After starting the pre-pitch pump, turn on the white water pump. When the normal level of the filter is reached, the lower limit alarm indicator is extinguished; as the liquid level rises, the filter disc rotates. A vacuum is generated in the leg and a slurry layer is formed on the filter plate. At this time, the valve for dip water is opened and the turbidity filter pump and the filter pump are started to start the spiral motor; the speed of the filter plate is changed from 'manual' to 'automatic'. The filter enters normal operation.

3.1.3 Shutdown procedure Shut off the white water pump and the pre-pumped pump until the lower limit indicator light of the filter level becomes bright; when there is no plasma layer on the filter plate, close the turbidity (clear) filtrate pump and close the valve of the sizing water; close out Spiral motor; Open the drain valve until the tank empties; Maintain the washing state for 10 to 15 minutes, close the filter and automatic control system; After cleaning the filter tank, close the sewage outlet.

3.1.4 Emergency Shutdown When the sector plate comes off or other serious fault occurs, the filter disk motor should be immediately shut down, and then other shutdown procedures should be performed.

3.2 Precautions In order to prevent the occurrence of pulp paste webs affecting the papermaking machine, the filter should be washed and replaced regularly. The filter is brushed once a week with a brush (specifically, the degree of slime production and the white water temperature should also be taken into consideration); in addition, an appropriate amount of chloramine should be added during the scrubbing process. (Addition of hypochlorite and Ammonium sulphate formulation) can effectively inhibit the formation of microorganisms; a filter plate is formed for every 12 sector boards (divided into 3 groups and replaced with 1 group per month) and replaced once every quarter to improve filtration capacity.

During the production process, it is necessary to pay attention to strengthening the equipment inspection. If problems are found, they should be immediately dealt with. If the filter is damaged, it should be immediately shut down for replacement. In particular, when a serious fault occurs, it should be shut down for troubleshooting.

The level of the filter disc should be within 120 mm of the central axis. The liquid level is too high, the strength of the pulp layer is low, the pulping is incomplete and the pulping of the sector plate is difficult; the liquid level is too low, the recovery capacity is low, and the vacuum degree should just disappear after the fan-shaped plate is transferred out of the liquid surface, but the peeling should be prevented. Difficulties arise during pulping.

When the plastic net is set, it is required that the opening of the sector plate is as large as possible and the opening is flat, so as to effectively prevent the disappearance of the leakage of plasma and vacuum, reduce the filtering efficiency, and facilitate the replacement of the seal pad.

The use and improvement of side pressure concentrators for equipments Guo Lun, Liu Mingqing, and Zhao Hongwei (Heilongjiang Province Tangyuan Paper Co., Ltd., Jiamusi 154701, Heilongjiang Province) Our company currently has 12 lateral pressure concentrators in operation, which are mainly used as pulp before and after bleaching. Washing. After long-term use, we found that the lateral pressure concentrator has the following two disadvantages: First, sometimes the slurry washing effect is not good; second, the roller leans out of the ditch. In response to the above problems, we conducted a research and achieved a better solution.

1 The washing effect is not good. 1.1 Pulp position The pulp position of the low side pressure concentrator to the pulp side is controlled very low, and no side pressure can be formed. The main reason is that the operator is afraid of the occurrence of slurry accidents. He prefers pulp to have lower insurance. In response to this problem, we installed a liquid level controller on the slurry piping of the side pressure concentrator. Since the position of the shaft of the liquid level control board was not rusted, it was the liquid level control board that was heavily pulped and was selected by 3.2.5 as a suitable process condition. Strainer. In general, as the screen mesh increases, the recovery efficiency gradually increases. For example, if the filter screen is increased from 80 meshes to 95 meshes, the recovery efficiency can be increased from 70% to over 85%. In addition to factors such as mesh, weaving method, strength, etc., we must consider whether the processing size and material can meet the heat setting under 100*C and the shrinkage after the excess of the netting, so that the filter after heat setting Can be flat and tightly set on the sector board. The filter should meet the following requirements: shrinkage rate of 10% to 15%, series strength 500N/cm, density 36/cm (through density), 23/cm (weft density), warp and weft diameter of 0.28mm, texture structure is twill (2 up and 2 down).

The fan-shaped plates shall be installed so that the filter plates formed by the fan-shaped plates are in the same plane, and the plates are kept parallel to each other. In this way, the position of the squeezing nozzle can be placed on the edge of each sector plate to ensure the quality of the sliver.

Determine the amount of lining addition and fiber length. Appropriately increase the fiber length and the lining amount, the average fiber length of the lining pulp is preferably 1. 4~1.8mm, and the cracking length is above 5000m, which is favorable for improving the strength of the pulp layer and overcoming the high content of fine fibers in the padding slurry. Disadvantages: The slurry does not break when rolling down, stabilizing filtration capacity, and improving recovery efficiency.

System application. Southwest Paper, 2001 (6).

Water recycling applications. Southwest Paper, 2001 (1).

Stuck and failed to promote use. Later, an overflow pipe was installed on the feed side to return the excess slurry to the feed pool. This eliminates the need for special management and eliminates slurry spillage and achieves the purpose of controlling the slurry level.

1.2 The volume of the storage tank is small After the storage tank is small, the volume of bleaching machine is intentionally increased to increase the output. Due to the low dilution rate of the slurry, the slurry is not thoroughly washed. Our approach is to install a dilution pipe on the suction pipe before the slurry pump so that the slurry is evenly diluted, thus improving the washing efficiency.

2 Roller yule out of the groove The seal knife under the rubber roll has dry pulp and grinds the roll into a groove. The reason is that the rubber roller is lax, so that the slurry turns with the roller to the sealing blade and is retained by the rubber blade. When the slurry gets more and more, a pad is formed between the sealing rubber blade and the rubber roller. Layer, and the more crowded dry, so that the roller out of the ditch.

Solution: Install a spray pipe under the inner side of the rubber roller to clean the rubber roller. This cleaning water can also be used as a diluted slurry.

The rubber roller scraper sometimes catches wire ropes and other debris and can also wear the rubber roller. Solution: To enhance the clean production of the workshop, it can be controlled.

PC Steel Bar Cutting And Straighten Machine

This product is a special equipment used for high strength PC bar cutting. The machine body adopts the new stye pressure cylinder to cut off the power, and there is the air source and can carry out cutting efficiently. Cutting tool is leading industry design, special treatment, its life is 8 times of domestic similar products. The electric control system use inverter to control the rebar transmission, realize the forward segment high speed transportation, the tail segment low speed buffer. Besides, it can assist the domestic and foreign first-class cylinders, electromagnetic valve and other components, improve the working efficiency and prolong the service life of the machine under the premise of ensuring the cutting accuracy.

PC bar cutting machine

PC bar cutting machine 2

The technical paramters:

No.

Item

Specification

1

Air source

MAX7.2kg∕cm²(0.1mpa)

2

Max cutting capacity

13T

3

Iinput voltage

three phase,four wire,AC380V±5%,50Hz

4

Cutting tolerance

Cutting tolerance allow±1mm

5

Hauling maximum speed

38M/min

6

Mmachine size

L×W×H=17000×700×2100

UNIT(mm)

7

Mmachine weight

2T

8

Ssame specification devide

 

devide left hand(model:z)and right hand(model:Y)two operations

9

Cutting PC bar diameter

ø7.1,ø9.0,ø10.7,ø12.6

10

Operation knife and fixed knife specification

ø7.1,ø9.0,ø10.7,ø12.6

Steel Bar Cutting And Straighten Machine

Steel Wire Cutting Machine,Pc Bar Cut Machine ,Steel Bar Straighten Machine,Cutting And Straighten Machine

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