Calculation of thickener productivity for paper pulp production. Thickening of mass and arrangement of thickeners. List of used literature

Ministry of Education of the Russian Federation

Perm State Technical University

Department of TCBP

Group TCBPz-04

COURSE PROJECT

Topic: “Calculation of the stock preparation department of a paper machine producing paper for corrugation”

Akulov B.V.

Perm, 2009

Introduction

1. Characteristics of raw materials and finished products

Introduction

Paper is of great economic importance and its production. Paper production technology is complex, as it is often associated with the simultaneous use of fibrous semi-finished products with different properties, large amounts of water, thermal and electrical energy, auxiliary chemicals and other resources and is accompanied by the formation of a large amount of production waste and effluent, which has a harmful effect on the environment. .

Assessing the general state of the problem, it should be noted that according to the European Confederation of Paper Producers (CEPI), since the beginning of the 90s, the volume of waste paper recycling in the world has increased by more than 69%, in Europe - by 55%. With total reserves of waste paper estimated at 230-260 million tons, approximately 150 million tons were collected in 2000, and by 2005 the collection is projected to increase to 190 million tons. At the same time, the average world consumption level will be 48%. Against this background, the indicators for Russia are more than modest. The total resources of waste paper are about 2 million tons. The volume of its procurement has been reduced compared to 1980 from 1.6 to 1.2 million tons.

Against the background of these negative trends in Russia, the developed countries of the world over these 10 years, on the contrary, have increased the degree of state regulation in this area. In order to reduce the cost of products using waste, tax incentives were introduced. To attract investors to this area, a system of preferential loans has been created; in a number of countries, restrictions are imposed on the consumption of products manufactured without the use of waste, and so on. The European Parliament adopted a 5-year program to improve the use of recycled resources: in particular paper and cardboard up to 55%.

According to some experts in industrialized countries, at present, from an economic point of view, it is advisable to recycle up to 56% of waste paper raw materials from the total amount of waste paper. In Russia, about 35% of this raw material can be collected, while the rest of the waste paper, mainly in the form of household waste, ends up in a landfill, and therefore it is necessary to improve the system of its collection and storage.

Modern technologies and equipment for processing waste paper allow it to be used not only for the production of low-quality, but also high-quality products. Obtaining high-quality products requires the presence of additional equipment and the introduction of chemical auxiliaries to refine the mass. This trend is clearly visible in descriptions of foreign technological lines.

The corrugated cardboard industry is the largest consumer of waste paper and its main component is old cardboard boxes and boxes.

One of the decisive conditions for improving the quality of finished products, including strength indicators, is improving the quality of raw materials: sorting waste paper by grade and improving its purification from various contaminants. The increasing degree of contamination of secondary raw materials negatively affects the quality of products. To increase the efficiency of using waste paper, it is necessary to match its quality to the type of product being manufactured. Thus, container board and paper for corrugation should be produced using waste paper mainly of MS-4A, MS-5B and MS-6B grades in accordance with GOST 10700, which ensures the achievement of high product performance.

In general, the rapid growth in the use of waste paper is due to the following factors:

The competitiveness of the production of paper and cardboard from waste paper raw materials;

The relatively high cost of wood raw materials, especially taking into account transportation;

The relatively low capital intensity of projects for new enterprises operating on waste paper compared to enterprises using primary fiber raw materials;

Ease of creating new small businesses;

Increased demand for recycled fiber paper and board due to lower cost;

Government legislation (future).

Another trend worth noting in the field of waste paper recycling is the slow decline in its quality. For example, the quality of Austrian containerboard is continuously declining. Between 1980 and 1995, the flexural stiffness of its middle layer decreased by an average of 13%. The systematic repeated return of fiber to production makes this process almost inevitable.

1. Characteristics of raw materials and finished products

Characteristics of the feedstock are shown in Table 1.1.

Table 1.1. Brand, type and composition of waste paper used for the production of corrugated paper

Waste paper brand
	Unbleached kraft paper	Waste from paper production: packaging twine, electrical insulation, cartridge, bag, abrasive base, base for adhesive tape, as well as punched cards.
	Non-moisture-resistant paper bags	Used bags without bitumen impregnation, interlayer, reinforced layers, as well as residues of abrasive and chemically active substances.
	Corrugated cardboard and containers	Waste from the production of paper and cardboard used in the production of corrugated cardboard, without printing, adhesive tape and metal inclusions, without impregnation, coating with polyethylene and other water-repellent materials.
	Corrugated cardboard and containers	Waste from the production and consumption of paper and cardboard, used in the production of corrugated cardboard with printing without adhesive tape and metal inclusions, without impregnation, coating with polyethylene and other water-repellent materials.
	Corrugated cardboard and containers	Waste from the consumption of paper and cardboard, as well as used corrugated containers with printing without impregnation, coating with polyethylene and other water-repellent materials.

2. Selection and justification of the production flow diagram

Forming of the paper web takes place on the mesh table of the paper machine. The quality of paper largely depends on both the conditions of entry onto the grid and the conditions of its dewatering.

Characteristics of paper machine, composition.

In this course project, a mass preparation department will be designed for a paper machine producing corrugated paper weighing 1 m 2 100 - 125 g, speed - 600 m/min, cutting width - 4200 mm, composition - 100% waste paper.

Main design solutions:

Installation of fire protection equipment

Advantages: due to repeated sequential passage of waste from the first stage of purification through other stages, the amount of usable fiber in the waste is reduced and the number of heavy inclusions at the last stage of purification increases. Waste from the last stage is removed from the installation.

Installation of SVP-2.5

Advantages:

· supply of the sorted suspension to the lower part of the housing prevents heavy inclusions from entering the sorting zone, which prevents mechanical damage to the rotor and sieve;

· heavy inclusions are collected in a heavy waste collection and removed as they accumulate during operating sorting;

· in the sorting, a semi-closed rotor with special blades is used, which allows the sorting process to be carried out without supplying water to dilute the waste;

· mechanical seals made of siliconized graphite are used in the sorting, which ensures high reliability and durability of both the seal itself and the bearing supports.

Parts of the screens that come into contact with the suspension being processed are made of corrosion-resistant steel type 12Х18Н10Т.

Installation of a hydrodynamic headbox with regulation of the transverse profile by local changes in mass concentration

Advantages:

· the range of regulation of the weight of 1 m 2 of paper is greater than in conventional boxes;

· the weight of 1 m 2 of paper can be changed in sections by dividing 50 mm, which improves the uniformity of the transverse profile of the paper;

· the zones of influence of regulation are clearly limited.

The method of producing paper on flat mesh paper machines, despite the widespread use and significant improvement of the equipment and technology used, is not without drawbacks. They noticeably manifested themselves when the machine was operating at high speed, and these were due to increased requirements for the quality of the paper being produced. A special feature of paper produced on flat mesh paper machines is some difference in the properties of its surfaces (versatility). The mesh side of the paper has a more pronounced mesh imprint on its surface and a more pronounced orientation of the fibers in the machine direction.

The main disadvantage of conventional forming on one mesh is that the water moves only in one direction and therefore there is an uneven distribution of fillers and fine fibers throughout the thickness of the paper. The part of the sheet that comes into contact with the mesh always contains less filler and fine fiber fractions than the opposite side. In addition, when the machine speed is over 750 m/min, due to the action of the built-in air flow and the operation of the dewatering elements at the beginning of the mesh table, waves and splashes appear on the mass filling mirror, which reduce the quality of the product.

The use of two-mesh forming devices is associated not only with the desire to eliminate the versatility of the paper produced. When using such devices, prospects have opened up for a significant increase in paper machine speed and productivity, because in this case, the speed of the filtered water and the filtration path are significantly reduced.

When using double-mesh forming devices, these are characterized by improved printing properties, a reduction in the dimensions of the mesh part and power consumption, simplified maintenance during operation and greater uniformity of the mass profile of 1 m 2 papers at high speed of paper machine operation. The Sim-Former forming device commonly used in practice is a combination of a flat and double-mesh machine. At the beginning of the formation of the paper web occurs due to the smooth removal of water on the forming board and subsequent single adjustable hydroplanes and wet suction boxes. Its further molding occurs between two meshes, where first, above the arcuate surface of the waterproof forming shoe, water is removed through the upper mesh, and then into suction boxes installed below. This ensures a symmetrical distribution of fine fiber and filler in the cross section of the paper web and its surface properties on both sides are approximately the same.

In this course project, a flat mesh machine was adopted, consisting of: a console table, a chest, rotating mesh and mesh drive shafts, a suction couch roll, a forming box, dewatering elements (hydroplane, wet and dry suction boxes), scrapers, mesh straighteners, mesh tensioners, spray systems, walkways service.

In paper production, the choice of cleaning and sorting equipment is also of great importance. Fiber contaminants have different origins, shapes and sizes. Depending on the density, inclusions found in the mass are divided into three groups: with a density greater than the density of the fiber (metal particles, sand, etc.); with a density less than the density of the fiber (resin, air bubbles, oils, etc.); with a density close to or equal to the density of the fiber (chips, bark, firewood, etc.). Removal of the first two types of contaminants is the task of the cleaning process and is carried out at the waste treatment plant, etc. Separation of the third type of inclusions is usually a task of the sorting process, carried out in sortings of various types.

The purification of the mass at the waste treatment plant is carried out according to a three-stage scheme. Modern designs of waste treatment plants have a completely closed system, operate with back pressure at the waste outlet, and when used in front of a paper machine, are also equipped with devices for deaerating the mass or work together.

Pressure screens are closed screens with hydrodynamic blades, used for such and coarse sorting of fibrous mass. A distinctive feature of this type of screening is the presence of special profile blades designed for cleaning sieves.

Screens of the UZ type are single screens with hydrodynamic blades, located in the zone of the sorted mass. These sorters are used mainly for fine screening of pulp cleaned at the UVK, immediately before the paper machine. SCN type sortings are installed to sort waste from the knotter.

3. Calculation of the material balance of water and fiber on the paper machine

Initial data for calculation

Composition of corrugated paper:

Waste paper 100%

Starch 8 kg/t

The initial data for the calculation are presented in Table 3.1

Table 3.1. Initial data for calculating the water and fiber balance

Data name	Magnitude
1. Composition of corrugated paper, %
Waste paper
2. Dryness of the paper web and mass concentration during the technological process, %
waste paper coming from a high concentration pool
in the waste paper receiving pool
in the machine pool
in the pressure overflow tank
at the third stage of centric cleaners
at the second stage of centric cleaners
waste after the third stage of centric cleaners
waste after the second stage of centric cleaners
waste after the first stage of centric cleaners
waste from the knotter
waste from vibration sorting
for vibration sorting
sorted mass from vibratory sorting into the recycling water collector
in the headbox
after the preliminary dehydration section
after suction boxes
after the cauch shaft
cut-offs and rejects from the couch shaft
after the press part
defects in the press section
after the drying part
defects in the drying section
defects in finishing
after coasting
after slitting machine
in a couch mixer
in pulpers
return defect after thickener
from the concentration regulator of the waste pool
3. Amount of paper waste from paper production, net, %
in finishing (from machine calender and rolling)
in the drying section
in the press area
cut-offs and wet marriage with gouch - shaft
4. Amount of sorting waste from incoming mass, %
from the knotter
from the third stage of centric cleaners
from the second stage of centric cleaners
5. Concentration of circulating water %
from the couch shaft
pressed water from the press part into the drain
from the press part, water from washing the cloth into the drain
from suction boxes
from the pre-dewatering area to the sub-grid water collection
from the pre-dewatering area to the recycled water collection
from the thickener to the collection of excess recycled water
6. Mass overflow,%
from the headbox
from the pressure overflow tank
7. Cellulose consumption per sublayer, kg
8. Degree of fiber collection on the disk filter, %
9. Fresh water consumption, kg
for defoaming in the headbox
for washing the mesh
for washing cloth
for cutoffs
for thickener

Longitudinal cutting machine

From rolling forward

dry waste in pulper

The amount of dry waste is 1.8% of net production, i.e.

Check substance water mass

consumption: to warehouse 930.00 70.00 1000.00

marriage 16.74 1.26 18.00

Total 946.74 71.26 1018.00

arrival: from roll 946.74 71.26 1018.00

Machine calender and rolling (finishing)

dry waste in pulper

The amount of dry scrap from calender and reeling is 1.50% of net production, i.e.

Check substance water mass

Total 960.69 72.31 1033.00

Drying part

from the press part

The amount of dry waste is 1.50% of net production, i.e.

Check substance water mass

consumption: for calender 960.69 72.31 1033.00

Total 974.64 1329.47 2304.11

We assume that the dryness of the cloth does not change after washing, then if the waste contains 0.01% fiber, its total weight will be 4000.40 kg. Fiber losses with these waters are 4000.40-4000 = 0.4 kg.

Wet scrap from the couch shaft is 1.00% of net production,

those. at humidity 7.00%

The cutoffs are 1.00% of net production, i.e.

at humidity 7.00%

on the couch shaft

on suction boxes

The overflow of sub-grid water into the collector is 10.00% of the incoming mass,

The amount of waste from the knotter is 3.50% of the incoming mass, i.e.

Waste dilution unit for vibration sorting

The amount of waste from vibration sorting is 3.00% of the incoming mass, i.e.

We accept the amount of waste from the III stage of waste treatment - 2.00 kg. Waste from the III stage of FTP constitutes 5.00% of the incoming fiber

Concentration of circulating water in the collection tank

Waste from the second stage of FRP constitutes 5.00% of the incoming fiber, i.e.

to the 2nd stage of labor protection

to the knotter

to the 1st stage

Check substance water mass

The overflow is 10.00% of the incoming mass, i.e.

to pulse mill

in the marriage thickener

in the pool of wet marriage

because then

The degree of fiber collection on the disk filter is 90%, i.e.

for the concentration regulator of the waste pool

in the composition pool

into the pressure overflow tank

machine pool

We calculate starch with a concentration of 10 g / l

B 4 =800 - 8=792kg

In table 3.2 shows the consumption of clarified water.

Table 3.2. Consumption of clarified water (kg/t)

The excess of clarified water is

The loss of fiber with clarified water is

The summary balance of water and fiber is presented in table. 3.3.

Table 3.3. Summary table of water and fiber balance

Income and expense items
Fiber + chemical ingredients (absolutely dry matter):
Waste paper
Cellulose on sublayer
Finished paper
Fiber with water from presses
Vibratory sorting waste
Waste from the third stage of centric cleaners
Fiber with clarified water
with waste paper
with cellulose on the sublayer
with starch glue
for washing cloth
for cutoffs
for sealing the vacuum chambers of the couch shaft
for sealing suction boxes
for cleaning the mesh
for defoaming
for thickener
in finished paper
evaporates when dried
from presses
with waste from vibratory sorting
with waste from the third stage of centric cleaners
clarified water

The irretrievable fiber loss is

The fiber wash is equal to

The consumption of fresh fiber per 1 ton of net paper is 933.29 kg of absolutely dry (waste paper + cellulose on the sublayer) or air-dried fiber, including cellulose.

4. Calculation of the mass preparation department and machine productivity

Calculations for the stock preparation department of a papermaking machine producing corrugated paper:

Weight 1m 2 100-125g

B/m speed 600 m/min

Cutting width 4200 mm

Composition:

Waste paper - 100%

The maximum calculated hourly productivity of the machine during continuous operation.

Вн - width of the paper web at reeling, m;

V - maximum operating speed, m/min;

q - maximum weight of 1m2 of paper, g/m2;

0.06 is the multiplier for converting minute speed to hourly speed and paper weight.

Maximum estimated output of the machine (gross output) during continuous operation per day

Average daily machine productivity (net output)

Keff - efficiency factor of machine use

K EF =K 1 K 2 K 3 =0.76 where

K 1 - coefficient of utilization of machine working time; at V<750 = 0,937

K 2 - coefficient taking into account defects on the car and idling of the car, = 0.92

K 3 - technological coefficient of use of the maximum speed of the machine, taking into account its fluctuations associated with the quality of semi-finished products and other technological factors, for mass types of paper = 0.9

Annual machine output

thousand tons/year

We calculate the capacity of pools based on the maximum amount of mass to be stored and the required storage time of the mass in the pool.

where M is the maximum amount of mass;

P H - hourly productivity;

t - mass storage time, h;

K - coefficient taking into account incomplete filling of the pool = 1.2.

High concentration pool volume

Volume of the composite pool

Reception basin volume

Machine basin volume

Wet scrap pool volume

Dry scrap pool volume

Recycling pool volume

The characteristics of the pools are shown in Table 4.1.

Table 4.1. Characteristics of swimming pools

To correctly select the type and type of grinding equipment, it is necessary to take into account the influence of factors: the place of the grinding apparatus in the technological scheme, the type and nature of the grinding material, the concentration and temperature of the mass.

To process dry waste, a pulper with the required maximum productivity is installed (80% of the net output of the machine)

349.27 H 0.8= 279.42 t

We accept GRVn-32

For finishing defects, a hydraulic pulper GRVn-6 is installed

Technical characteristics are shown in table 4.2.

Table 4.2. Technical characteristics of pulpers

Cleaning type installations

We accept UOT 25 at the first stage

Technical characteristics are shown in table 4.3

Table 4.3. Technical characteristics of UOT

Knotter

We accept SVP-2.5, productivity 480-600 t/day, technical characteristics are indicated in table 4.4

Table 4.4. Technical specifications

Parameter
Mass productivity w.d.w. sorted suspension, t/day, at the mass concentration of the incoming suspension:
Side surface area of ​​the sieve drum, m 2
Electric motor power, kW
Nominal diameter of pipes DN, mm:
Suspension feed
Suspension removal
Removal of light inclusions

Vibration sorting

We accept VS-1.2 productivity 12-24 t/day

Technical characteristics are shown in table 4.5.

Table 4.5. Technical specifications

Parameter
Mass productivity w.d.w. sorted suspension (waste from sorting paper pulp with a sieve hole diameter of 2 mm), t/day
Mass concentration of incoming suspension, g/l
Sieve area, m 2
Electric motors: - quantity - power, kW
Nominal diameter of pipes DN, mm: - supply of suspension - discharge of sorted suspension
Overall dimensions, mm
Weight, kg

Calculation of centrifugal pumps

High Concentration Pool Pump:

reception basin pump:

composite pool pump:

machine pool pump:

wet scrap pool pump:

dry scrap pool pump:

mixing pump No. 1:

mixing pump No. 2:

mixing pump No. 3:

sub-grid water collection pump:

return water collection pump:

Couch mixer pump:

Main technical and economic indicators of the workshop

Electricity consumption kW/h……….................................................... .......275

Steam consumption for drying, t……………………………………………3.15

Fresh water consumption, m 3 /t……………………………………………………23

water fiber paper making machine

List of information sources used

1. Paper technology: lecture notes / Perm. state tech. univ. Perm, 2003. 80 p. R.H. Khakimov, S.G. Ermakov

2. Calculation of water and fiber balance for a paper machine / Perm. state tech. univ. Perm, 1982. 44 p.

3. Calculations for the pulp preparation department of a paper mill / Perm. state tech. univ. Perm, 1997

4. Paper technology: guidelines for course and diploma design / Perm. state tech. univ. Perm, 51s., B.V. Akulov

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The drive for the GT-12S thickener is designed for installation on farms of single-tier heavy-duty closed-type thickeners.

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Mass thickening and thickener arrangement

The mass concentration after sorting is low - from 0.4 to 0.7 . Operations in the preparatory department of a paper mill - concentration control, composition and accumulation of some stock of pulp in pools - should be carried out with a thicker pulp. Otherwise, very large capacity pools would be required. Therefore, after sorting, a good mass is sent to thickeners, where it is thickened to a concentration of 5.5-7.5’. During the thickening of the mass, most of the warm water entering circulation is separated. This circumstance is of great importance, as it helps maintain normal operation on defibrators using the hot liquid defibration method.

The thickener device diagram is shown in Fig. 1.

Bath. Thickener baths are usually cast iron, sometimes concrete. In old factories, thickeners with wooden baths are found. On the end walls of the bath there is a device in the form of poles or valves to regulate the level of waste circulating water.

Cylinder. The frame of the cylinder is formed from a series of rings resting on slats supported by spokes. A number of cast iron crosspieces are mounted on a steel shaft. On the circumference of the rings, chamfers are milled into which brass rods are installed on the edge along the entire generatrix of the cylinder, forming the frame of the cylinder. Sometimes brass rods are replaced with wooden ones, but the latter wear out quickly and are impractical.

As the experience of our enterprises shows, rods can be successfully replaced with sheets of perforated stainless steel 4 mm thick and secured to specially installed support rims.

A lower brass mesh, called a lining mesh, is placed on the surface of the cylinder, and an upper mesh No. 65-70 is placed on top of it. The mesh consists of warp threads (running along the fabric) and weft threads (running across the fabric).

These mesh cells, as well as the holes of the sieves, make up their Live Section. Sometimes a middle net No. 25-30 is placed between the upper and lower nets. There are special edges at the ends of the cylinder, and corresponding protrusions on the end walls of the bath, which are used for putting on bandages (one at each end of the cylinder). Steel bands with cloth gaskets are tightened with bolts; their purpose is to prevent the mass from leaking into the circulating water through the gaps between the cylinder and the bath.

Rice. 1. Diagram of the thickener device: 1 - overhead wooden box; 2 - cast iron bath; 3 - mesh rotating drum; 4 - drive (idler and working) pulleys; 5 - drive gears; 6- receiving (pressure) roller; 7- inclined plane; 8 - scraper; 9 - mixing pool of condensed mass

Receiving roller. The receiving roller is made of wood or cast iron. The surface of the roller is wrapped with woolen cloth in several turns (layers), and the width of the cloth should be 150-180 mm greater than the length of the roller so that it can be pulled together and secured. Typically, tare cloth from the press rolls of papermaking machines is used.

The roller rotates in bearings mounted on levers. A special lifting mechanism, consisting of two flywheels (one at each end of the cylinder), spindles and springs, regulates the degree of pressure of the roller to the drum, as well as its raising and lowering.

In thickeners of a later design, the take-up roller is made of metal with a lining of soft rubber, and therefore there is no need to wrap it with cloth.

Scraper. The receiving shaft scraper with an adjustable clamp is usually made of wood (oak wood); he scrapes the thickened mass from the roller, which then falls into the mixing basin. Outside the cylinder, across its entire width, there is a shredder pipe with a diameter of 50-60 mm, which serves to wash the mesh from small fibers.

Loop box. The inlet (pressure) box in front of the bath serves to distribute the mass evenly across the entire width of the cylinder; it is usually made in the form of a funnel. The mass is brought to the box from below and, rising upward, gradually “calms down”, evenly distributed over the width of the cylinder. Sometimes, to calm the mass, a perforated distribution board with holes with a diameter of 60-70 mm is installed in the upper part of the box.

It is very important that the liquid mass entering the bath does not fall on the layer of fiber deposited on the drum mesh, since in this case it will wash it away, which will significantly reduce the efficiency of the thickener. Therefore, often across the entire width of the cylinder, at a distance of 60-70 mm from its surface, a metal shield bent into a semicircle is installed on top, which protects the cylinder from contact with uncondensed mass.

Some thickener designs do not have an inlet box. The mass is fed directly into the lower part of the bath under the distribution board (a steel sheet covering the inlet hole at an angle). Hitting the shield, the mass is evenly distributed over the entire surface of the cylinder.

Due to the difference in the levels of the liquid entering the condensation outside the cylinder and the circulating water leaving inside the cylinder, the mass is sucked to the rotating cylinder. In this case, most of the water is filtered through the mesh cells, and the condensed fiber is deposited in an even layer over the entire width of the cylinder, additionally squeezed out with a receiving roller, removed with a scraper and fed into the mixing pool. A small part of the fiber does not pass between the cylinder and the receiving roller; it is pressed by the latter to the edges of the cylinder and is directed along special water chutes along with the entire condensed mass into the mixing pool. The concentration of the mass coming from the gutters is much lower and is usually 1.5-2.5%.

A person is constantly concerned about how to make his life easier. Look around you, think about what everyday items you couldn’t do without. Everyone will have their own long list. But we can say with confidence that there is a place on the list for toilet paper and disposable napkins. In Russia, toilet paper began to be produced only in nineteen sixty-eight, and before that they did not know about its existence and got along just fine without it.

What are toilet paper and disposable napkins made from?

Paper for the production of disposable napkins and paper is made using special technologies. Cellulose and waste paper are the raw materials for their production. They can be used separately or mixed. A special paper pulp is made from the prepared raw materials, and toilet paper and disposable napkins are already made from it.

Lad-M company offers all the necessary equipment:

YTS Series Cylindrical Sieve

DRUM (HORIZONTAL) CLEANER

VERTICAL PRESSURE SCREENING

LOW CONCENTRATION VERTICAL CLEANER

CONSTANT VERTICAL CUTTER OF MEDIUM CONCENTRATION

VERTICAL CONSTANT LOW CONCENTRATION CLEANER

VIBRATION SORTING

VORTEX CLEANER FOR LIGHT INCLUDES

HIGH CONCENTRATION HYDRATEURER ZGS

SCRAPER

In the production of any paper, paper pulp is considered to be an aqueous suspension containing the necessary substances for making paper.

The process of producing paper and napkins takes place in several stages:

• It all starts with preparing the mass itself - this is the first stage;
• The second stage is the production of paper products from it.

Paper pulp can be made from not just any waste paper. Only certain types are suitable, namely: white paper made from cellulose, lined paper also white with black or colored stripes, book, magazine and archival paper (without covers, paper clips, bindings). You can also use cardboard, magazines, newspapers. The content of unusable paper in waste paper will lead to a decrease in the quality of the manufactured product.

The following types of paper cannot be used to make paper pulp:

• covered with polyethylene, varnish, films, fabric;
• impregnated with various substances;
• burnt paper and cardboard;
• containing other materials: fabrics, ropes, wood, polyethylene;
• located in medical and veterinary institutions.

After collecting the required waste paper, special equipment for the preparation of paper pulp dissolves the raw material from waste paper or cellulose into small fibers to a homogeneous mass, and is also cleaned of various impurities.

Next, using special equipment, the raw material goes through several stages of cleaning and grinding, and is diluted with water to the desired consistency. Having gone through all the procedures, we obtain paper pulp ready for the production of toilet paper and disposable napkins. Thus, the quality of the mass depends on the quality of the raw materials, and the quality of the manufactured product depends on it, in turn.

Berezniki Polytechnic College
technology of inorganic substances
course project in the discipline "Processes and apparatus of chemical technology
on the topic: "Selection and calculation of a slurry thickener
Berezniki 2014

Technical specifications
Nominal diameter of the vat, m 9
Depth of the vat, m 3
Nominal deposition area, m 60
Raising height of the rowing device, mm 400
Duration of one stroke revolution, min 5
Conditional productivity for solids at density
condensed product 60-70% and specific gravity of solid 2.5 t/m,
90 t/day
Drive unit
Electric motor
Type 4AM112MA6UZ
Speed, rpm 960
Power, kW 3
V-belt drive
Belt type A-1400T
Gear ratio 2
Gearbox
Type Ts2U 200 40 12kg
Gear ratio 40
Rotation gear ratio 46
Total gear ratio 4800
Lifting mechanism
Electric motor
Type 4AM112MA6UZ
Speed, rpm 960
Power, kW 2.2
V-belt drive
Belt type A-1600T
Gear ratio 2.37
Worm gear ratio 40
Overall gear ratio 94.8
Load capacity
Nominal, t 6
Maximum, t 15
Rising time, min 4

Compound: Assembly drawing (SB), Rotation mechanism, PZ

Software: KOMPAS-3D 14