Principle of Operation
Products supplying the equipment are initially distributed between two rollers whose distance is adjustable . The working cylinders Products by compression and shear .
The roller speed and roller type are defined in accordance with the work . The slow ( internal) and mobile roll and fast roll ( external) is fixed.
Separating the endosperm goal of ensuring peel the finish of sharps without harming the very bark and consequently alter the quality of flour, mainly in ash content .
Parts of a cylinder :
1.Distribuição
* Globe supply.
Globe Power is intended to facilitate the distribution of the product throughout the length distribution , and lung also serves to maintain product flow in the cylinders. It is necessary that the product is distributed precisely along the entire length of the roll grinding to keep uniform , avoiding vibrations and reduction in yield. In a perfect distribution , the product mono falls layers over the entire length of the rollers being driven in the region between the rollers . The product should be distributed and homogeneous monolayers quantitatively and qualitatively .
* Rollers product distribution
Types of Rollers Distribution :
* It is used spline roller anterior and posterior reduction and compression in the cylinders . The fluted cylinder brings with slight slope 5 for better distribution of the product . The slope encourages distribution throughout the length of the roller.
* It is used in posterior position to extract the product from crushing .
* It is used in the previous position of the passages grinding - diamond tips .
The speed of the rollers of distribution can be done in two ways :
* Mechanically : using pulleys
* Electronically : automatic when banks are independent motors to move the rollers distribution , we can vary the speed of the same electronically via frequency inverters .
2.Válvulas :
It is of great importance for adjustment of the grinding cylinder banks , it is from these that standardizes the layer thickness of the product to be milled.
3.Defletores :
Are sets of plates that direct the product to the grinding zone .
They should cushion the product, therefore, should have a slope close to 90 ° and must break parallel paths to ensure a mono layer between the cylinders . It serves as the air deflector ( not allow the whirling air between the rollers) to break the flow of air from the interior of the cylinder banks .
Grinding Cylinders :
The grinding rolls perform various functions , depending on their position in the diagram of the mill. In Crunch , they have the effect of cutting to open the grain of wheat and scrape the endosperm with minimal dust production bran . Reduction and Compression in , however, the goal is to reduce the size of the endosperm to obtain a flour with minimal damage to the starch .
Grinding rolls consist of a pair of rollers and brushes to clean the surface . The pair of rollers rotates inward, where it is crushed or reduced by the pressure exerted by them.
Length of rolls:
1000 mm
1250 mm
800 mm
diameter :
250 mm
220 mm
The rolls are cast iron , externally treated to provide a hard surface, the hard surface depth is approximately 1 cm. During milling, and because heating of the rolls there is a tendency for a small expansion of the rolls , particularly in the extremities. To avoid such a problem, the rolls are gradually lowered approximately 15 cm 0.04 mm at each end . ( Bulging )
The two rollers do not rotate at the same speed because they could make flakes of the product , making screening difficult and reduces the efficiency of the process. Generally the upper roller ( external) is faster than the lower (inner ) .
In Crushing speed difference is 2.5:1
T1/T2 - Rapid roller rotates 650 rpm .
T3/T4/T5 - Quick rollers reduce gradually to 550 rpm .
speed difference is 1.25:1 , the rapid roller rotates 500 rpm .
Flights to Germ: whose behavior when going through smooth rolls is to increase in size, the speed ratio is 1 : 1 .
Nature of the surface and position of Rolls:
* ROLLS rifled :
NOTE: Position the rollers : First fast , then slow.
A- Cut / Cut
B - Back / Cutting
C-Corte/Dorso
D - Back / Back
OBS :
The back / back position favors compression , lower production Meal .
The court / court position favors the shear , higher production Meal .
Mirror Streak :
100 º to 115 º
40 º to 45 º
60 º to 70 º
Characteristics of rays :
* Dimensions : no. per cm :
Grows from T1 to T5 going from 4 lanes / cm to 10 or 11 rays / cm .
* Profile :
It is characterized by the angles ( on the cut) and ( on the back) , their values are generally presented in the figure above .
* Mirror :
Its function is to prevent the cutting edge of the tooth . It is also called as a witness because it was draw conclusions on the wear of the roll or her perfect alignment. Width: 2 to 3/ 10 mm on T1 2/10 mm in T2 1/10 mm to T3 on.
OBS :
** The number of rays per cm both in slow roll in as fast is the same .
The higher ** No. of streaks per inch , the higher the attack to the product .
** The thicker is the smallest product is no. of rays per cm .
** The steeper the slope between the rays , the greater the paragraph . actions that the streak has on the product .
In ** milling head tilt is less increasing as it approaches the end of the milling group .
Table raiação rolls tickets streaks Tilt Angles % Mirror Position n.raias mm / cm T1 Total 3.82 300 45/65 8 0.3 D / D T2 5.41 425 45/65 10 0.2 D / D T3 7.32 575 45/65 12 0.1 C / C T4G 9.23 725 45/65 12 0.1 C / C T4F/T5G 10.5 825 45/65 14 0.1 C / C T5F 11.45 900 45/65 14 0.1 C / C
The maintenance of rays is a function of:
* The size of streaks ( thick or thin ) .
* From the slope of rays .
* The conduct of the mill , run empty as little as possible .
* The speed of the roller , the outer spins faster and therefore wears faster than the internal roll.
Result of worn lanes:
* Increased power consumption
Abnormal heating of the product, making it difficult to mill and sieve the increasing water loss.
* Difficulty in finishing the meal and increased extraction .
Table maintenance rays Ton for Cheap T1 to 1DM long T1 T2 2500-3000 4000-5000 6000-8000 T3 T4 T5 8000-9000 10000-15000
EXCHANGE OF ROLLS MUST BE ENCLOSED IN PREVENTIVE MAINTENANCE .
* ROLLS SMOOTH :
Can be smooth or rough , smooth over rough compressions and used in the reductions .
The rough cylinders receive a blast of air with particles of steel for the roughness . This roughness provides an increase in yield of flour to increase the shear .
Smooth cylinders should never be touched , because if the metal occurs if destempera .
The rollers are hollow and its inner wall must have a thickness such that does not allow warping ( small thickness ) , but also does not cause much dilation during labor .
The rifled cylinders are harder than smooth , hence one can turn the cylinder in smooth and rifled never smooth in rifled .
Relative disposition of Reels :
* Horizontal : It is the most used , facilitates feeding and product output .
* Vertical : In disuse entry very difficult product.
* Diagonal : The fastest roller is positioned at 45 º slow .
Transmission between rollers :
The drive is made by the bank roll fast and can be done by:
* For Gears : Resists high power , is simple , but has a drawback of losing the alignment of the gears after raiações .
* For current: Allows alignment of rollers after raiações , is noisy and the power ratio is limited .
* For Toothed Belts : You with a notched side and the two toothed sides . Approach allows the rollers after raiações absorbs satisfactory power being easy to maintain .
NOTE: There is a transmission system that uses a combination of gear and toothed belts .
Command cylinders .
* By Transmission: Made by belts
Advantages : better than the command by individual motors , simpler wiring installed power .
Disadvantages : inefficient Automation .
* For Solo Engines: Each cylinder has its individual engine.
Advantages : Facilitates the management and automation of the mill .
Disadvantages : Power consumption is higher . Cleaning the Rollers : Rollers T1 and T2 dispense cleaning, the other cylinders using :
Brushes : It is only used in the grinding , should just touch the rollers .
The brushes can be synthetic or animal hair or feathers .
Scraper : steel knives are tangent to the roll , making scraping the same . Are used only for plain rolls .
5.Regulagem the distance between the rolls :
The lower pair of rollers are adjustable . The support of each end is carried by an arm with a wheel bolt " handwheel ." This wheel is placed on both sides to adjust the grinding at both ends.
The roller mill is equipped with a release mechanism for the rollers, which can be done manually or automatically ( by compressed air ) when no food product in preventing wear of the rollers by friction .
HUMIDIFICATION
HUMIDIFICATION
It is nothing more than adding water to wheat for it to get ideal conditions for milling , making it more flexible and crispy bran. The water enters the grain through the side of the germ also over the entire surface of the shell ( bran ) and fills the space between the germ and the endosperm . The amount of absorbed water depends on the grain structure of the grain and its initial moisture content .
Some factors influence the hydration of wheat :
We should never add more than 4% water once because the water absorption capacity of wheat by seed coat is at most 4% . To add more , a second humidification , which should be 6 to 8 hours after the first is needed. All humidification is necessarily followed by a beat wheat optimum distribution of water on the surface of the grain .
Intensive dampener
The thread has molhadora rotor fitted with beaters that promote beating of wheat with water in order to homogenize the mixture of wheat with water . These batters should be sufficient to allow the distribution of water across the surface of the grain number. We must promote maximum contact between the grain mass and water
2nd CLEANING :
After rest and consequently the homogenization of the moisture grain , wheat goes through a cleansing supplement that aims to give a finish cleaning 1st . It is possible to give a final surface treatment on the grain in order to try to eliminate the dust that perhaps is still adhered to the grain .
The grain passes through a polishing machine which will eliminate the fragmented by the action of the pericarp of the grain during the swelling preparation. It is vital to remember the need for a good vacuum at the outlet of the polisher .
2nd HUMIDIFICATION
Is to add 0.25% to 0.50 % water to half to two hours before it is sent to the milling wheat .
The purpose of this second wetting is to prevent the bran breakage during milling lot , you should get a compatible with the other requirements of milling moisture, which is more important than humidified far enough to prevent the separation of the endosperm from the bark .
In wheats Hard and Semi -hard must add as much water as possible with up to 24 to 36 hours of rest
In Soft wheats should decrease the amount of water and rest time 12 to 18 hours , add water should be only enough to let loose flexible and bran.
CONSEQUENCES OF A POOR PREPARATION •
Excessive wear of rays cylinder •
Black tips on flour •
Poor distribution of products between cylinders •
Difficulty of grinding ( Lack or excess of water) •
High ash content in flour •
Low extraction •
Contamination of flour.
It is nothing more than adding water to wheat for it to get ideal conditions for milling , making it more flexible and crispy bran. The water enters the grain through the side of the germ also over the entire surface of the shell ( bran ) and fills the space between the germ and the endosperm . The amount of absorbed water depends on the grain structure of the grain and its initial moisture content .
Some factors influence the hydration of wheat :
We should never add more than 4% water once because the water absorption capacity of wheat by seed coat is at most 4% . To add more , a second humidification , which should be 6 to 8 hours after the first is needed. All humidification is necessarily followed by a beat wheat optimum distribution of water on the surface of the grain .
Intensive dampener
The thread has molhadora rotor fitted with beaters that promote beating of wheat with water in order to homogenize the mixture of wheat with water . These batters should be sufficient to allow the distribution of water across the surface of the grain number. We must promote maximum contact between the grain mass and water
2nd CLEANING :
After rest and consequently the homogenization of the moisture grain , wheat goes through a cleansing supplement that aims to give a finish cleaning 1st . It is possible to give a final surface treatment on the grain in order to try to eliminate the dust that perhaps is still adhered to the grain .
The grain passes through a polishing machine which will eliminate the fragmented by the action of the pericarp of the grain during the swelling preparation. It is vital to remember the need for a good vacuum at the outlet of the polisher .
2nd HUMIDIFICATION
Is to add 0.25% to 0.50 % water to half to two hours before it is sent to the milling wheat .
The purpose of this second wetting is to prevent the bran breakage during milling lot , you should get a compatible with the other requirements of milling moisture, which is more important than humidified far enough to prevent the separation of the endosperm from the bark .
In wheats Hard and Semi -hard must add as much water as possible with up to 24 to 36 hours of rest
In Soft wheats should decrease the amount of water and rest time 12 to 18 hours , add water should be only enough to let loose flexible and bran.
CONSEQUENCES OF A POOR PREPARATION •
Excessive wear of rays cylinder •
Black tips on flour •
Poor distribution of products between cylinders •
Difficulty of grinding ( Lack or excess of water) •
High ash content in flour •
Low extraction •
Contamination of flour.
AUXILIARY MACHINERY
AUXILIARY MACHINERY
They are the ones that assist the main engine during the milling process , allowing them a better income , and consequently a better end result of grinding .
1 . Disruptive
Are usually installed below the banks of smooth rollers . Works similar to desinfestador , causing friction with product vanes at high rpm . Its main function is to reduce the platelets formed during the passage of the products by the cylinders , also reducing the endosperm particles in the passage already fissured by drums, all before the screening . The machines are indispensable crumbling after stints Reduction and Compression . They are used to relieve the compression load on C1 and C2, being installed at the outlet of dividers planschister .
Disintegrants type :
centrifugal
Property can be pins or channels ( turbines ) , have also desinfestar . They are used in passages head as R1, R2 , C1, C2, C3 , it is used increases the extraction of flour without affecting the quality . Speed of 3600 rpm .
Drum
Efficiency lower than the centrifugal are used in passages reduction and compression tail , not very intensely pulverize the product in order to obtain a higher ash content , which affect the quality of the flour. It has an independent transmission and speed of 1200 rpm .
2 . Dredges
This equipment is composed of a cylindrical housing having a central axis containing three palettes and a display involving this axis. The product is thrown against the screen at high speed , a part of the product is sieved and the other is rejected .
Basically we have two functions for dredges :
When rupture extractor is installed at the exit of the 4th and 5th grinding cylinders , its function is to replace sieves scrap planschister . Has the advantage of gaining space in planschister sieves for flour.
Terminators When Bran is installed at the exit of planschister 3rd , 4th and 5th crunch , its function is to complement the work of the cylinder banks , removing a load of flour still aggregate the bark to be separated in the vibro centrifuges. These flours for being too close to the bark have a high fat feature .
3 . VIBROCENTRÍFUGAS
It's a machine like the dredges , but with centrifugal and vibratory movements . The product exits the dredges enters Vibros being thrown against the screen separating the peel flour .
The opening screen of Vibros is below 250 microns .
They can also be used as:
In the penultimate passage grinding C6 With advantage of saving planschister .
Used as extractor Bran exerting the same function of excavators .
Safety before bagging . Eliminate contamination.
They are the ones that assist the main engine during the milling process , allowing them a better income , and consequently a better end result of grinding .
1 . Disruptive
Are usually installed below the banks of smooth rollers . Works similar to desinfestador , causing friction with product vanes at high rpm . Its main function is to reduce the platelets formed during the passage of the products by the cylinders , also reducing the endosperm particles in the passage already fissured by drums, all before the screening . The machines are indispensable crumbling after stints Reduction and Compression . They are used to relieve the compression load on C1 and C2, being installed at the outlet of dividers planschister .
Disintegrants type :
centrifugal
Property can be pins or channels ( turbines ) , have also desinfestar . They are used in passages head as R1, R2 , C1, C2, C3 , it is used increases the extraction of flour without affecting the quality . Speed of 3600 rpm .
Drum
Efficiency lower than the centrifugal are used in passages reduction and compression tail , not very intensely pulverize the product in order to obtain a higher ash content , which affect the quality of the flour. It has an independent transmission and speed of 1200 rpm .
2 . Dredges
This equipment is composed of a cylindrical housing having a central axis containing three palettes and a display involving this axis. The product is thrown against the screen at high speed , a part of the product is sieved and the other is rejected .
Basically we have two functions for dredges :
When rupture extractor is installed at the exit of the 4th and 5th grinding cylinders , its function is to replace sieves scrap planschister . Has the advantage of gaining space in planschister sieves for flour.
Terminators When Bran is installed at the exit of planschister 3rd , 4th and 5th crunch , its function is to complement the work of the cylinder banks , removing a load of flour still aggregate the bark to be separated in the vibro centrifuges. These flours for being too close to the bark have a high fat feature .
3 . VIBROCENTRÍFUGAS
It's a machine like the dredges , but with centrifugal and vibratory movements . The product exits the dredges enters Vibros being thrown against the screen separating the peel flour .
The opening screen of Vibros is below 250 microns .
They can also be used as:
In the penultimate passage grinding C6 With advantage of saving planschister .
Used as extractor Bran exerting the same function of excavators .
Safety before bagging . Eliminate contamination.
PLANSIFTERS
PLANSIFTERS
Pillars of a screening :
•
Abrasion / friction •
Surface ( % opening / Voltage of the screens ) . •
RPM and eccentricity
The plansifters consist of sieves arranged in a box , are driven by a shaft with a starter motor in eccentric movements , circular .
Is the separation of products from various gauges , animated by stacking sieves a circular motion making the smallest fraction passing through the openings , and the largest fraction rejected . It is therefore of a size classification .
The plansifter receives products from the cylinders , these products are usually transported by pneumatic system , are separated in cyclones ( the product suffers a drop in speed and decant ) , and unloaded by a rotary valve . In plansifter are sorted by difference in particle size and routed according to the diagram grinding .
Types Plansifter
•
The drawers are stacked screens in easel planschister but are inserted into side rails , allowing the removal of any single sieve , anywhere without having to remove the sieves that are above it .
However, it has two major drawbacks to the use of this type of plansifter : first loses about 12 % of the area of screening , and can have major problems of product leaks through drawers . •
The overlapping layers sieves and their trays are stacked one over the other . Each stack is secured with a metal frame , and each sieving comprises several cells.
The size of the screens varies according to the type and model of the plansifter , but is usually approximately 150 x 50 cm and depth of 7 to 8 cm .
Although this type of plansifter is very efficient , it has low capacity screening relative to the size of the screen , and to inspect or change a screen requires a lot of space , time and manpower. •
Square sieves sieves are square and of equal size , which makes it to be so interchangeable , are stacked on one another and can be pressed to ensure the tension and prevent leakage of product
The square sifters have high capacity screening because intermediate frames can be used to adjust the height so as to adjust the volume of the cell .
Sieve Types
Long Screeners - (120 cm comp. ) .
Semi - long sieves - ( 80 cm comp. )
Square sieves - ( 50 cm comp. )
Factors influencing the flow in plansifter
All refers to the product:
• Density According to the progress in crushing the specific weight decreases . This feature determines the use of spacers and paragraph . entries in Plansifter . •
Particle size
A product is sieved well as the relationship between the amount of product that enters the plansifter and quantity of extracted product through the screen tends to 1. Closer to 1 for the highest ratio is the flow . •
Particle shape
The product has a rounded shape screening easier . •
moisture
The higher the humidity the more difficult is the grading . Excessively wet wheat considerably reduces the capacity of the mill. •
temperature
The higher temperature is more difficult to sieve
Relative Humidity
The relative humidity in the mill should be low , hence the need for a good vacuum . The higher the relative humidity is more difficult sifting .
Working surface of the sieves .
The actual sifting sieve surface is approximately 85%. The higher this is the largest surface of the sifting plansifter .
feed
The supply must be well distributed to avoid disproportions in screening .
No greater . Entries higher absorption capacity of the product by the plansifter housing.
headroom
The goal is to ensure the free flow time of rejection .
Disruptions - 8 cm Max Headroom on the screen .
Reductions beginning - 4 cm
Final reductions - 3 cm
Chimneys of product output
Should be sufficient for the whole product flow space to avoid congestion in the output.
Speed or time rating
As one increases the rotation of plansifters , decreases the speed of advance of the product because it increases the thickness and length of the above product sieves , increasing the extraction of the product sieves .
Since it can not hold a product on a screen so that it is enough for the desired separation time, it increases the path , that is the number of sieves in order to increase the travel time . Among various ways to vary the speed of classification highlights the change in mesh size , thus slowing or speeding the grading .
Cleaning Screens
There are many cleaning screens systems , each adapting to a kind of sieve. •
• brush
Tapotins ( Cleaners ) - They are fast in operation, simpler and more field action brushes . On the other hand do not clean the bottom of the sieve can be: •
Cotton - always choose a firm plot, not shred , sometimes get impregnated products that increases their resistance . •
Plastic or Rubber - should observe the quality of the material and cleaner format , can wear out too fast or do not clean well screens or even pierce them .
Pillars of a screening :
•
Surface ( % opening / Voltage of the screens ) . •
RPM and eccentricity
The plansifters consist of sieves arranged in a box , are driven by a shaft with a starter motor in eccentric movements , circular .
Is the separation of products from various gauges , animated by stacking sieves a circular motion making the smallest fraction passing through the openings , and the largest fraction rejected . It is therefore of a size classification .
The plansifter receives products from the cylinders , these products are usually transported by pneumatic system , are separated in cyclones ( the product suffers a drop in speed and decant ) , and unloaded by a rotary valve . In plansifter are sorted by difference in particle size and routed according to the diagram grinding .
Types Plansifter
•
The drawers are stacked screens in easel planschister but are inserted into side rails , allowing the removal of any single sieve , anywhere without having to remove the sieves that are above it .
However, it has two major drawbacks to the use of this type of plansifter : first loses about 12 % of the area of screening , and can have major problems of product leaks through drawers . •
The overlapping layers sieves and their trays are stacked one over the other . Each stack is secured with a metal frame , and each sieving comprises several cells.
The size of the screens varies according to the type and model of the plansifter , but is usually approximately 150 x 50 cm and depth of 7 to 8 cm .
Although this type of plansifter is very efficient , it has low capacity screening relative to the size of the screen , and to inspect or change a screen requires a lot of space , time and manpower. •
Square sieves sieves are square and of equal size , which makes it to be so interchangeable , are stacked on one another and can be pressed to ensure the tension and prevent leakage of product
The square sifters have high capacity screening because intermediate frames can be used to adjust the height so as to adjust the volume of the cell .
Sieve Types
Long Screeners - (120 cm comp. ) .
Semi - long sieves - ( 80 cm comp. )
Square sieves - ( 50 cm comp. )
Factors influencing the flow in plansifter
All refers to the product:
• Density According to the progress in crushing the specific weight decreases . This feature determines the use of spacers and paragraph . entries in Plansifter . •
Particle size
A product is sieved well as the relationship between the amount of product that enters the plansifter and quantity of extracted product through the screen tends to 1. Closer to 1 for the highest ratio is the flow . •
Particle shape
The product has a rounded shape screening easier . •
moisture
The higher the humidity the more difficult is the grading . Excessively wet wheat considerably reduces the capacity of the mill. •
temperature
The higher temperature is more difficult to sieve
Relative Humidity
The relative humidity in the mill should be low , hence the need for a good vacuum . The higher the relative humidity is more difficult sifting .
Working surface of the sieves .
The actual sifting sieve surface is approximately 85%. The higher this is the largest surface of the sifting plansifter .
feed
The supply must be well distributed to avoid disproportions in screening .
No greater . Entries higher absorption capacity of the product by the plansifter housing.
headroom
The goal is to ensure the free flow time of rejection .
Disruptions - 8 cm Max Headroom on the screen .
Reductions beginning - 4 cm
Final reductions - 3 cm
Chimneys of product output
Should be sufficient for the whole product flow space to avoid congestion in the output.
Speed or time rating
As one increases the rotation of plansifters , decreases the speed of advance of the product because it increases the thickness and length of the above product sieves , increasing the extraction of the product sieves .
Since it can not hold a product on a screen so that it is enough for the desired separation time, it increases the path , that is the number of sieves in order to increase the travel time . Among various ways to vary the speed of classification highlights the change in mesh size , thus slowing or speeding the grading .
Cleaning Screens
There are many cleaning screens systems , each adapting to a kind of sieve. •
• brush
Tapotins ( Cleaners ) - They are fast in operation, simpler and more field action brushes . On the other hand do not clean the bottom of the sieve can be: •
Cotton - always choose a firm plot, not shred , sometimes get impregnated products that increases their resistance . •
Plastic or Rubber - should observe the quality of the material and cleaner format , can wear out too fast or do not clean well screens or even pierce them .
Sassor purifying meal
Sassor
Sassor
purifying meal
The Sassores separators or scrubbers are using the principles of density and air resistance , to separate particles husk ( chaff) of endosperm ( flour).
After the cylinders milled product is classified under planschisters , large bran particles are separated and sent back to the group milling . The separation plansifter is the only difference in particle size , therefore classified in the same product will have bran particles of the same particle size of the endosperm.
The purifiers can be used to separate the bran particles of endosperm based on the difference in density and air resistance . This classification is achieved through a sieve made with direct suction on the product , the lighter product rich in shell passes over the screens suspended in the air , while the heavier , rich endosperm is sifted .
The purpose of this separation is to grind products with similar characteristics always the same cylinder and obtain flour of superior quality . The separation of the particles of bran and endosperm by a scrubber depends on the difference in aerodynamic property of the particles . These properties depend on the size , density and air resistance of these particles.
The material supplied to the classifier is composed of three categories :
Endosperm particles ;
Particles of endosperm and bran ;
Particles of pure bran ;
In general, the particles contain large amounts of bran , tends to be lighter than one with less bran. When a mixture of these three types of particles is exposed to an air stream ( moving upward) , and the mixture is stratified in various separate layers ( from bottom to top ) :
Particles of pure endosperm in the background ;
Particles composed of bran and endosperm in the middle;
Particles of pure bran on top .
In reality, however the cleanser separation is not so simple , though it has been classified in planschister and to be seemingly homogeneous mixture with respect to particle size the mixture contains particles of different sizes.
The mixture separated in the scrubber is generally composed of 6 to 7 components:
Particles of pure , small and large endosperm;
Endosperm and bran particles , small and large ;
Particles of pure , small and large bran ;
Fine particles of flour .
Therefore, placing the mixture on a sieve and exposing it to a stream of air from bottom to top , the mixture separates into multiple layers, but there is no clear dividing line between them.
The following layers are produced from the bottom up :
• Small particles of pure endosperm in the background ;
• Large pure endosperm particles ;
• Small particles composed of endosperm and bran ;
• Large Composite particles of endosperm and bran ;
• large bran particles ;
• Small particles of bran ;
• Very fine particles of bran and flour , above all .
To achieve good separation purifier in this last layer should be eliminated . This is achieved by a good regulation of the system avoiding breakage of grain formation of very fine particles of bran and good in plansifter sieve to remove particles of flour. The more calibrated for the product to be classified, it is next particle size difference , the better the work Sassor . The sieves Sassor are distributed so that the power input screen is thinner aperture and near the exit aperture is higher.
The aperture size is chosen so that the thinner endosperm can be sieved through a sieve closest to the entrance, but the larger the particle the more it is run through the Sassor before finally passing through the screen or not . The thinner the endosperm , which is screened at the entrance , is separated by Sassor purer product , while coarse endosperm , which is sieved near the end of sieving , is usually adhered to particles of endosperm bran formed, and not is as pure as separate early . Particles of pure bran and bran with endosperm are separated on the sieve ( rejection ) , and collected in a special output at the end of Sassor .
Control Sassor
For a control function and successful purifiers , we should note the following items :
• Feed speed :
The product should be supplied to the purifier , so that a continuous layer is formed on the screen . If there are areas without layers of products, the air enters at a higher speed , resulting in a suspension of particles of endosperm. With this there will be an uneven distribution of air, causing a separation or stratification poor product .
• Moves sifter :
The oscillating sifter as well as the slope and the alignment should be checked properly. Excessive vertical movement too advances the product, the product sufficient movement will stop at the top of the sieve preventing air to pass through the sieve . The setting is only effective when sifter screens are appropriately strained ( stretched ) , the tension should be checked regularly and adjusted if necessary .
• Airflow :
Excessive air flow will load endosperm particles to the vacuum system . Lack of air will carry particles of bran to the meal . The air consumption of Sassores is approximately 50 m3 per min , so you must ensure free access to air purifiers . Low air pressure slows the purifier and poor separation .
• Limit the ability : The cleanser should work as close to capacity.
• Cover the sieve ( screen ) :
The screen number in scrubber to be used depends largely on the particle size of the product being supplied to the scrubber and the velocity of feeding.
The 1st screen must be larger than the smallest particles of endosperm opening being provided as the last screen opening should be equal to or slightly larger endosperm particles , so as to allow them to be separated.
The sieves and the Air
The mesh size has to increase from the first to the last sieve. The air velocity is also increasing .
A great feature of this operation is the passage of air through the sieves .
The distribution of the product on the screen has to be uniform so that it classifies .
A moderate speed favors the first sieve classification.
The air flow must be regulated so as not charging light particles .
Brushes
The cleaning system shall be provided so as to " disengage " the meal . A malfunction of the brushes completely nullifies the function of the machine , sending products rich in endosperm to the end of grinding .
Sassor
purifying meal
The Sassores separators or scrubbers are using the principles of density and air resistance , to separate particles husk ( chaff) of endosperm ( flour).
After the cylinders milled product is classified under planschisters , large bran particles are separated and sent back to the group milling . The separation plansifter is the only difference in particle size , therefore classified in the same product will have bran particles of the same particle size of the endosperm.
The purifiers can be used to separate the bran particles of endosperm based on the difference in density and air resistance . This classification is achieved through a sieve made with direct suction on the product , the lighter product rich in shell passes over the screens suspended in the air , while the heavier , rich endosperm is sifted .
The purpose of this separation is to grind products with similar characteristics always the same cylinder and obtain flour of superior quality . The separation of the particles of bran and endosperm by a scrubber depends on the difference in aerodynamic property of the particles . These properties depend on the size , density and air resistance of these particles.
The material supplied to the classifier is composed of three categories :
Endosperm particles ;
Particles of endosperm and bran ;
Particles of pure bran ;
In general, the particles contain large amounts of bran , tends to be lighter than one with less bran. When a mixture of these three types of particles is exposed to an air stream ( moving upward) , and the mixture is stratified in various separate layers ( from bottom to top ) :
Particles of pure endosperm in the background ;
Particles composed of bran and endosperm in the middle;
Particles of pure bran on top .
In reality, however the cleanser separation is not so simple , though it has been classified in planschister and to be seemingly homogeneous mixture with respect to particle size the mixture contains particles of different sizes.
The mixture separated in the scrubber is generally composed of 6 to 7 components:
Particles of pure , small and large endosperm;
Endosperm and bran particles , small and large ;
Particles of pure , small and large bran ;
Fine particles of flour .
Therefore, placing the mixture on a sieve and exposing it to a stream of air from bottom to top , the mixture separates into multiple layers, but there is no clear dividing line between them.
The following layers are produced from the bottom up :
• Small particles of pure endosperm in the background ;
• Large pure endosperm particles ;
• Small particles composed of endosperm and bran ;
• Large Composite particles of endosperm and bran ;
• large bran particles ;
• Small particles of bran ;
• Very fine particles of bran and flour , above all .
To achieve good separation purifier in this last layer should be eliminated . This is achieved by a good regulation of the system avoiding breakage of grain formation of very fine particles of bran and good in plansifter sieve to remove particles of flour. The more calibrated for the product to be classified, it is next particle size difference , the better the work Sassor . The sieves Sassor are distributed so that the power input screen is thinner aperture and near the exit aperture is higher.
The aperture size is chosen so that the thinner endosperm can be sieved through a sieve closest to the entrance, but the larger the particle the more it is run through the Sassor before finally passing through the screen or not . The thinner the endosperm , which is screened at the entrance , is separated by Sassor purer product , while coarse endosperm , which is sieved near the end of sieving , is usually adhered to particles of endosperm bran formed, and not is as pure as separate early . Particles of pure bran and bran with endosperm are separated on the sieve ( rejection ) , and collected in a special output at the end of Sassor .
Control Sassor
For a control function and successful purifiers , we should note the following items :
• Feed speed :
The product should be supplied to the purifier , so that a continuous layer is formed on the screen . If there are areas without layers of products, the air enters at a higher speed , resulting in a suspension of particles of endosperm. With this there will be an uneven distribution of air, causing a separation or stratification poor product .
• Moves sifter :
The oscillating sifter as well as the slope and the alignment should be checked properly. Excessive vertical movement too advances the product, the product sufficient movement will stop at the top of the sieve preventing air to pass through the sieve . The setting is only effective when sifter screens are appropriately strained ( stretched ) , the tension should be checked regularly and adjusted if necessary .
• Airflow :
Excessive air flow will load endosperm particles to the vacuum system . Lack of air will carry particles of bran to the meal . The air consumption of Sassores is approximately 50 m3 per min , so you must ensure free access to air purifiers . Low air pressure slows the purifier and poor separation .
• Limit the ability : The cleanser should work as close to capacity.
• Cover the sieve ( screen ) :
The screen number in scrubber to be used depends largely on the particle size of the product being supplied to the scrubber and the velocity of feeding.
The 1st screen must be larger than the smallest particles of endosperm opening being provided as the last screen opening should be equal to or slightly larger endosperm particles , so as to allow them to be separated.
The sieves and the Air
The mesh size has to increase from the first to the last sieve. The air velocity is also increasing .
A great feature of this operation is the passage of air through the sieves .
The distribution of the product on the screen has to be uniform so that it classifies .
A moderate speed favors the first sieve classification.
The air flow must be regulated so as not charging light particles .
Brushes
The cleaning system shall be provided so as to " disengage " the meal . A malfunction of the brushes completely nullifies the function of the machine , sending products rich in endosperm to the end of grinding .
LAND OF WHEAT
LAND OF WHEAT
Wheat is one of the oldest foods in history and most widespread in the world. It is also the main source of calories from vegetable consumed by man . Haunts the variety : some talk at 30 000 types .
It is one of the oldest foods in history and most widespread in the world. It is also the main source of calories from vegetable consumed by man . Haunts the variety : there are those who speak in 30000 types .
After the fruit of the tree of good and evil , which turned out to Adam and Eve from Paradise , speaks of wheat 's oldest literary reference about the history of food. Archaeological evidence effectively attest their presence in the most remote addresses known to man , in Jarmo , in the northeast of what is now Iraq , ancient Mesopotamia , around 7000 BC Since then , the product has spread planet apart and there is no latitude or longitude where it will not germinate.
There is wheat in Jericho , the Middle East , 250 meters below sea level . And there is wheat in Tibet , Central Asia , 3500 meters above. For its spectacular tolerance , wheat thrives in winter , cold seasons of Iceland and also in the wild heat of Ethiopia .
Actually , you can not describe any sort of broader or more importantly food. Not even a brother his rice .
On the whole globe , the essential raw material is always a grain . At least half of the cultivated soils of the earth surrenders to a genus of cereal. Thanks to cereal humanity absorbs approximately 80 % of the calories you need. Wheat provides two fifths of that pie . Even the two most overcrowded nations and simultaneously among the least well fed the entire planet as India and China .
Almost 55 % of properties in Australia are home grown wheat. Their vibrantly planting helps sustain prosperous economies of countries like the United States and Canada . And grows excellent quality wheat in different regions so as Cuba , Egypt and Afghanistan.
It was in Asia , moreover , between Afghanistan and Israel , that wheat originated naturally in ancient times . Later, probably during the Neolithic ( between 10 000 and 7000 years ago) , came to be seeded with some organization. Today , it seems impossible to set the number of its varieties . A German botanist , Helmuth Pelshenke , recorded 12 000 . Vazilov The Soviet scientist Nicolai , more meticulous, noted 30 000. All this multiplicity that relief! derived from only two roots , so-called hard wheat, or Triticum durum and common wheat, one of which is used for bread flour, Triticum vulgare . Interestingly and spectacularly , the T. durum not know anything beyond ten or twelve leads . All others are part of the genealogy of T. vulgare including , lost for eternity , certainly the mother of the breed lies , spontaneous kind of millennia ago .
In an attempt to put some order in this immense confusion, modern botanicals ended up dividing the types of wheat in at least three categories according to the number of chromosomes in their cells findable Playlist: seven, fourteen , or 21 pairs . The early varieties , according to this proposition , ostentariam mere seven pairs , as a curious and prosaic Ethiopian plant, whose spike settles a single grain . The leads of T. vulgare, in turn, is generally prove more sophisticated carry fourteen pairs. In your department is located safely biblical wheat, Kussemeth Abraham . Also T. durum has fourteen pairs. The species is customarily dubbed " wheat noodles " because her Arabs and Sicilians began to perpetrate their masses in enviroments 1100.1200 after Christ .
Hence , a step up , stand out types of 21 pairs , contemporary hybrids actually those of the past 2000 years that , by intention or accident , since the acids of the Greeks and Romans, were by mixing and perfecting . Because of this orgy of genetic, uncontrolled and uncoded weddings , the grower of wheat, to sow it rarely knows what variety later will reap . The process is maddening . There are times when all seeds look exactly the same type of a clearly identified and determined . Then mowed the ears , one realizes that the grains do not offer uniformity in shape , size or even color. In general, stand out , for example, yellow beans and red beans . Only that the proportion is not repeated it changes , yes , madly , each new crop .
To further complicate the situation , U.S. farmers have devised their own independent classification, namely:
Durum wheat , red, winter From high protein , used in ultrafermentados and stiff bread flour.
Durum wheat , red spring With more protein also used in the same genre of breadmaking , as the Italians .
Durum wheat noodles in clear appearances .
White wheat appearances in non - fermented breads, pastas to cakes , confectionery , biscuits and noodles second line .
Common wheat winter appearances rather selectively in breads , cakes , biscuits and confectionery second line .
The characteristics of each type are more understandable when considering a grain of wheat, and describes its inner composition. Fundamentally , a grain of wheat is formed by its bark , for a germ and endosperm . The shell represents 14.5 % of the weight . The endosperm , 83 % . The germ , 2.5 % . Each of these parts differs from the other in terms of their chemical formulation. The germ in the kernel of grain is less minerals and vitamins ; As with most grains , the amount of such substances decreases from outside to inside .
The objective of milling wheat, basically , remove the skin and separate the endosperm from the germ. Endosperm flour if you can , in all its possibilities . Roughly speaking, the endosperm of hard wheat contains a higher amount of starch . In the manufacturing process of the flour , which leads to the production of pasta , the starch gelatinisation is the core of the mass , causing it to resist much longer cooking operations , thus obtaining the so-called al dente point . Instead, a pasta with less starch , pasta softens and sometimes crumbles .
It was an instinctive act of chewing suggest that primitive man the idea of crushing the grains of wheat between two rock chips . With the passage of decades , the lower portion of the stone turned into cavity, the principle of the theory of the pylon . Initially , nomadism , is obviously used laptop chips . When the man sat , sedentary , hit him the light to work with much larger pieces . The mill was created . Then it rained . The water that is blended the flour into a smooth paste . And that folder , after drying and autofermentada the open, showed interestingly edible . The bread was ready unintentionally .
For the occurrence of this result , crucially contributes a component of wheat, gluten , marriage of two proteins that become formidably elastic contact with moisture and heat . More protein and therefore more elastic . More elasticity, more aerated spaces in body mass . Because those spaces that induce accommodation of yeasts, autoproliferantes communities that lead to the growth of the mass . Primitive man did not know that .
Only , by inhabiting caves , stone houses or wooden overcrowded scenarios of fungi and yeasts , its mass increased volume without particular efforts . Someone smarter for sure one day discovered the wonder of injecting fungi collected from a wall or a trunk folder in your ground wheat and water and was delighted with the phenomenal result, the mass increased three to four times its initial weight .
Thanks to this rare peculiarity , wheat became inevitable partner of human evolution . The citizen of the Neolithic have cultivated wheat in the enviroments 7000 BC in Mesopotamia , near the Euphrates and Tigris rivers .
The Sumerian language, dated 3100 BC , gloriously reports that the man was able to perpetrate then eight different drinks, fermented from wheat , possibly moms of all beers . The Sumerian civilization , in fact , reached the refinement of irrigating their crops , so as to ensure the crops in the dry seasons . And the fascination of tradition continues.
Why the holy bread of the Hebrews , matzah , has no yeast in their composition ? Simply because the followers of Moses was compelled to flee hastily from their enslavers in Egypt . In the rush , had no way to add yeast to your usual pasta , your haversack travel . Survived , anyway , with altanaria . And today celebrating the feat in his Passover with unleavened matzah . The Phoenicians called it a god , Dagon , in honor of wheat . Athens became a maritime power because of their lack of geographical product Greeks needed pick him beyond the ocean , in the Middle East . In their popular assemblies , which were held ten times each year , the Hellenic invariably began discussions for analyzing the reports about the preciousness of inventories .
Rome took control of the Mediterranean around 400 BC because an Athenian defeat at Syracuse , on the island of Sicily , destroyed the entire Greek fleet and IHE cut off supplies of wheat, food essential to the discipline of his soldiers . The imperial expansionism of Rome then took the wheat from the entire Middle East to Europe. And the imperial expansionism of Europe by navigations of the sixteenth century , took the wheat to the New World . Christopher Columbus personally planted the first seed in the West Indies , in Isabela, Puerto Rico . The same Spanish landed product in Argentina . Incidentally, the wheat does not requires special practice, grows quickly and does not ask many conservation care , especially in temperate climates . Stand the cold and heat and just cringe when excess moisture is accompanied , simultaneously , the excess temperature. Irony. The problem does not occur because this dual action inhibits their growth , quite the contrary . Is because wheat grows excessivamente.Tanto that rises glorious in the heavens , a visual lush green and does not bother to form ears .
Superinteressante Issue 35 Land of wheat
Wheat is one of the oldest foods in history and most widespread in the world. It is also the main source of calories from vegetable consumed by man . Haunts the variety : some talk at 30 000 types .
It is one of the oldest foods in history and most widespread in the world. It is also the main source of calories from vegetable consumed by man . Haunts the variety : there are those who speak in 30000 types .
After the fruit of the tree of good and evil , which turned out to Adam and Eve from Paradise , speaks of wheat 's oldest literary reference about the history of food. Archaeological evidence effectively attest their presence in the most remote addresses known to man , in Jarmo , in the northeast of what is now Iraq , ancient Mesopotamia , around 7000 BC Since then , the product has spread planet apart and there is no latitude or longitude where it will not germinate.
There is wheat in Jericho , the Middle East , 250 meters below sea level . And there is wheat in Tibet , Central Asia , 3500 meters above. For its spectacular tolerance , wheat thrives in winter , cold seasons of Iceland and also in the wild heat of Ethiopia .
Actually , you can not describe any sort of broader or more importantly food. Not even a brother his rice .
On the whole globe , the essential raw material is always a grain . At least half of the cultivated soils of the earth surrenders to a genus of cereal. Thanks to cereal humanity absorbs approximately 80 % of the calories you need. Wheat provides two fifths of that pie . Even the two most overcrowded nations and simultaneously among the least well fed the entire planet as India and China .
Almost 55 % of properties in Australia are home grown wheat. Their vibrantly planting helps sustain prosperous economies of countries like the United States and Canada . And grows excellent quality wheat in different regions so as Cuba , Egypt and Afghanistan.
It was in Asia , moreover , between Afghanistan and Israel , that wheat originated naturally in ancient times . Later, probably during the Neolithic ( between 10 000 and 7000 years ago) , came to be seeded with some organization. Today , it seems impossible to set the number of its varieties . A German botanist , Helmuth Pelshenke , recorded 12 000 . Vazilov The Soviet scientist Nicolai , more meticulous, noted 30 000. All this multiplicity that relief! derived from only two roots , so-called hard wheat, or Triticum durum and common wheat, one of which is used for bread flour, Triticum vulgare . Interestingly and spectacularly , the T. durum not know anything beyond ten or twelve leads . All others are part of the genealogy of T. vulgare including , lost for eternity , certainly the mother of the breed lies , spontaneous kind of millennia ago .
In an attempt to put some order in this immense confusion, modern botanicals ended up dividing the types of wheat in at least three categories according to the number of chromosomes in their cells findable Playlist: seven, fourteen , or 21 pairs . The early varieties , according to this proposition , ostentariam mere seven pairs , as a curious and prosaic Ethiopian plant, whose spike settles a single grain . The leads of T. vulgare, in turn, is generally prove more sophisticated carry fourteen pairs. In your department is located safely biblical wheat, Kussemeth Abraham . Also T. durum has fourteen pairs. The species is customarily dubbed " wheat noodles " because her Arabs and Sicilians began to perpetrate their masses in enviroments 1100.1200 after Christ .
Hence , a step up , stand out types of 21 pairs , contemporary hybrids actually those of the past 2000 years that , by intention or accident , since the acids of the Greeks and Romans, were by mixing and perfecting . Because of this orgy of genetic, uncontrolled and uncoded weddings , the grower of wheat, to sow it rarely knows what variety later will reap . The process is maddening . There are times when all seeds look exactly the same type of a clearly identified and determined . Then mowed the ears , one realizes that the grains do not offer uniformity in shape , size or even color. In general, stand out , for example, yellow beans and red beans . Only that the proportion is not repeated it changes , yes , madly , each new crop .
To further complicate the situation , U.S. farmers have devised their own independent classification, namely:
Durum wheat , red, winter From high protein , used in ultrafermentados and stiff bread flour.
Durum wheat , red spring With more protein also used in the same genre of breadmaking , as the Italians .
Durum wheat noodles in clear appearances .
White wheat appearances in non - fermented breads, pastas to cakes , confectionery , biscuits and noodles second line .
Common wheat winter appearances rather selectively in breads , cakes , biscuits and confectionery second line .
The characteristics of each type are more understandable when considering a grain of wheat, and describes its inner composition. Fundamentally , a grain of wheat is formed by its bark , for a germ and endosperm . The shell represents 14.5 % of the weight . The endosperm , 83 % . The germ , 2.5 % . Each of these parts differs from the other in terms of their chemical formulation. The germ in the kernel of grain is less minerals and vitamins ; As with most grains , the amount of such substances decreases from outside to inside .
The objective of milling wheat, basically , remove the skin and separate the endosperm from the germ. Endosperm flour if you can , in all its possibilities . Roughly speaking, the endosperm of hard wheat contains a higher amount of starch . In the manufacturing process of the flour , which leads to the production of pasta , the starch gelatinisation is the core of the mass , causing it to resist much longer cooking operations , thus obtaining the so-called al dente point . Instead, a pasta with less starch , pasta softens and sometimes crumbles .
It was an instinctive act of chewing suggest that primitive man the idea of crushing the grains of wheat between two rock chips . With the passage of decades , the lower portion of the stone turned into cavity, the principle of the theory of the pylon . Initially , nomadism , is obviously used laptop chips . When the man sat , sedentary , hit him the light to work with much larger pieces . The mill was created . Then it rained . The water that is blended the flour into a smooth paste . And that folder , after drying and autofermentada the open, showed interestingly edible . The bread was ready unintentionally .
For the occurrence of this result , crucially contributes a component of wheat, gluten , marriage of two proteins that become formidably elastic contact with moisture and heat . More protein and therefore more elastic . More elasticity, more aerated spaces in body mass . Because those spaces that induce accommodation of yeasts, autoproliferantes communities that lead to the growth of the mass . Primitive man did not know that .
Only , by inhabiting caves , stone houses or wooden overcrowded scenarios of fungi and yeasts , its mass increased volume without particular efforts . Someone smarter for sure one day discovered the wonder of injecting fungi collected from a wall or a trunk folder in your ground wheat and water and was delighted with the phenomenal result, the mass increased three to four times its initial weight .
Thanks to this rare peculiarity , wheat became inevitable partner of human evolution . The citizen of the Neolithic have cultivated wheat in the enviroments 7000 BC in Mesopotamia , near the Euphrates and Tigris rivers .
The Sumerian language, dated 3100 BC , gloriously reports that the man was able to perpetrate then eight different drinks, fermented from wheat , possibly moms of all beers . The Sumerian civilization , in fact , reached the refinement of irrigating their crops , so as to ensure the crops in the dry seasons . And the fascination of tradition continues.
Why the holy bread of the Hebrews , matzah , has no yeast in their composition ? Simply because the followers of Moses was compelled to flee hastily from their enslavers in Egypt . In the rush , had no way to add yeast to your usual pasta , your haversack travel . Survived , anyway , with altanaria . And today celebrating the feat in his Passover with unleavened matzah . The Phoenicians called it a god , Dagon , in honor of wheat . Athens became a maritime power because of their lack of geographical product Greeks needed pick him beyond the ocean , in the Middle East . In their popular assemblies , which were held ten times each year , the Hellenic invariably began discussions for analyzing the reports about the preciousness of inventories .
Rome took control of the Mediterranean around 400 BC because an Athenian defeat at Syracuse , on the island of Sicily , destroyed the entire Greek fleet and IHE cut off supplies of wheat, food essential to the discipline of his soldiers . The imperial expansionism of Rome then took the wheat from the entire Middle East to Europe. And the imperial expansionism of Europe by navigations of the sixteenth century , took the wheat to the New World . Christopher Columbus personally planted the first seed in the West Indies , in Isabela, Puerto Rico . The same Spanish landed product in Argentina . Incidentally, the wheat does not requires special practice, grows quickly and does not ask many conservation care , especially in temperate climates . Stand the cold and heat and just cringe when excess moisture is accompanied , simultaneously , the excess temperature. Irony. The problem does not occur because this dual action inhibits their growth , quite the contrary . Is because wheat grows excessivamente.Tanto that rises glorious in the heavens , a visual lush green and does not bother to form ears .
Superinteressante Issue 35 Land of wheat
BAG FILTER
The air / contaminated gas enters the bottom side of the filter housing through the exhaust air duct. In the sleeves of the particulate matter separation occurs in the air, the particles being retained on the outside.
The respective solenoid valves are
controlled periodically by an electronic programmer. Solenoid valves are
periodically controlled by an electronic programmer or optionally by an
electronic differential pressure switch that releases the cleaning cycle to be
achieved a loss of pre-determined load. The compressed air discharged from the
reservoir is driven to each row of their sleeves and venturi tubes, pipes
through the nozzles. By gun effect, caused by the jet of compressed air is
dragged a high volume of filtered secondary air, causing a flow reversal and
sudden inflating the sleeves and the subsequent cleaning of the same.
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