New process of cassava starch production
Key words: cassava starch equipment, cassava starch processing machinery, cassava starch processing new process, a new cassava starch process
Cassava starch is mainly used as raw material for food, sugar, medicine, feed, textile, paper making, chemical industry and other industrial sectors.Cassava starch production process, is the physical separation process, that is, the cassava raw material starch and cellulose, white, inorganic and other substances separated.In the production process, it is as follows: starch is insoluble in cold water and its specific gravity is higher than water. Water and special mechanical equipment are used to separate starch from water suspension, so as to achieve the purpose of recovering starch.Its production process is divided into conveying, cleaning, shredding, dipping, screening, bleaching, sand removal, separation, dehydration, dry bath, air cooling, packaging and other processes.
Cassava starch raw materials include fresh cassava and cassava dried pieces, they are the main material of production, must ensure the quality, the requirement of fresh cassava fresh, the same day purchase, the same day into the factory, the same day processing, no mud, sand, roots, beard, wood parts and other impurities mixed;Cassava dry slice requirements dry, not moldy, not bad, no moth.The average composition of fresh cassava is as follows: starch 27% cellulose 4% protein 1% other 3% water 65% cassava dry slice average composition is: starch 68% cellulose 8% protein 3% other 8% water 13% due to cassava variety, harvesting time, natural conditions, production of water to different, the starch content of raw materials are different.
Sulfuric acid 2kg/t starch;Bleach 0.5kg/t starch;Potassium permanganate 0.1kg/t starch.
4. Process route
The wet processing technology of cassava starch includes roller cleaning, secondary crushing, concentrated pulp screening, counter-current washing, REDOX bleaching, cyclone desiccation, concentrated pulp separation, overflow dehydration and first-order negative pressure pulsed air drying.5. Process flow
Main process raw material preparation raw material is the material basis of production, the quality of raw material is directly related to the quality of products.The raw material of cassava starch factory has fresh cassava and cassava dry slice two kinds.
Fresh cassava harvested, should be promptly removed soil, roots, beard and wood parts, stacked on the clean ground, avoid mixing with iron blocks, nails, stones, wood and other sundries, the requirements of the day, the day into the factory, the day of processing, to ensure the freshness of raw materials, so as to improve the extraction rate and product quality.
Cassava dry pieces should be dry, not moldy, not bad, no moth-eaten, to ensure product quality.
The belt conveyor is used to transport the cassava from the storage yard to the cleaning machine. It is required to ensure the normal supply of raw materials in the process.In the process of conveying, iron, nails, stones, wood and other debris should be specially prevented from mixing.If found sundries, should be promptly picked out.Hsgx-850 drum-type washing machine and hsxs-850 pulp bar type potato washing machine are used for cleaning. The machine is divided into coarse washing area, bath area and clean washing area.Cassava material with the rotating drum wall rolling forward, with water as the medium spraying, washing, bathing, grinding, cleaning, peeling.The requirement is to clean the sediment by cleaning, and the peeling rate is above 80%.
Send clean cassava to cutting machine and then to file mill for shredding.Shredding destroys the tissue structure of cassava, allowing tiny starch particles to break up and separate from the root tubers.HSCM -600 stainless steel file mill is adopted, which makes the sawblade and sieve plate on the rotary drum file and smash the cassava continuously fed in the machine, so as to break cassava and separate the starch granules.with water as the medium, the broken cassava is processed into starch pulp.The crushed starch pulp passes through the sieve hole of 1.2-1.4mm.The thin starch pulp after breaking and stirring needs to be sifted so that the starch milk and fiber are separated.At the same time, the starch milk needs sieve to remove fine residue, fiber needs detergent to recover starch.
Through screening, the purpose of separating and purifying starch is achieved.Currently, the 4-stage HSLXS -850 vertical centrifugal screen is mainly used to remove fine residue.Generally adopt multiple screening or countercurrent washing technology.It is required to screen and wash the original pulp. The potato residue contains less than 35% starch and less than 5% free starch.The fiber impurity content of whey is lower than 0.05%.The concentration of whey reaches 5 ~ 6 baume degree.
Bleaching is an important link to guarantee the quality of cassava starch.Its functions are as follows: adjust the ph value of whey to control microbial activity, fermentation and saccharification;Accelerate the separation of starch and other impurities;Float away the colloid of starch granule outer layer, make starch granule lasting white.
In addition to the sand
According to the principle of specific gravity separation, the starch whey is pumped into the vortex by pressure pump to remove sand by bottom flow and flow through the pulp by top flow so as to achieve the purpose of removing sand.After sand removal, it can not only remove fine sand and other impurities, but also protect the disc separator.
The separation of
The function of separation is to separate insoluble protein and residual soluble protein and other impurities from starch milk, so as to achieve the purpose of washing, refining and concentrating starch milk.
Our company adopts hsxlq-360 type washing cyclone to wash, refine and concentrate starch whaler.It is separated according to the specific gravity of water, starch and yellow pulp protein.Generally, the grade 12 hsxlq-360 washing cyclone is used in series, and the pulp concentration is required to be 20 ~ 22 baume degree.
After the separation process, the concentrated whey still contains a lot of water, so it must be dehydrated to facilitate drying.
Our company adopts vacuum filter for dehydration.The moisture content of wet starch after dehydration is required to be less than 38%.
The wet starch dehydrated by vacuum filter is transported to air dryer for drying.Steam pressure is controlled at 0.8mpa.Requirements through drying, starch product moisture content in about 13.5%.
Packing and warehousing
Bags are required to be sufficient, securely sewed and put into storage in time.
7. Process requirements:
(1) must ensure the freshness of cassava raw materials, to ensure product quality and improve the recovery rate.
(2) the skin to net, because cyanide toxins mainly concentrated in the cassava cortex, to net potato skin can greatly reduce the cyanide content.
(3) in the process of processing water consumption is large, the requirements of processing water to drinking standards.
(4) do not use iron equipment and pipelines, because cyanide iron will combine into blue ferrous cyanide and starch color, affect the quality of starch.In addition, the whole production process of starch is basically slightly acidic, therefore, the equipment used, the best use of stainless steel pipe fittings.
(5) in the production process, the material transport volume is very large, so need more pumps.Various pumps not only play the role of transport, but also require a certain pressure, to give the material power, in order to achieve high-speed rotation of equipment at the time of separation.
6 as a result of starch easy precipitation properties, fiber is not uniform material, so pipe elbow and other parts should be flange or live joint, once plug easy to remove and clean.
7 to ensure product quality, in the production process should pay attention to cleaning equipment, site, keep clean and sanitary.
Today is acidic starch slurry, and therefore all slurry pool should be treated with preservatives.
9 in the drying process, should control and eliminate all kinds of flammable sources, such as smoking, welding, electrostatic spark and so on, to prevent dust explosion, ensure production safety.
8. Technological features:
(1) production process layout to plane process and vertical process combined, covers an area of less, with less pipe, with less pump, save investment, reduce energy consumption.
(2) short production process, from feeding to production of finished products only 30 minutes.
(3) continuous production process, high efficiency equipment.
(4) except the drying process, the whole production process is carried out under normal temperature and pressure conditions.
(5) through the use of new technology, can further improve the level of production process, give full play to the capacity of equipment, reduce the number of equipment, reduce energy consumption and production costs, increase output, improve product quality.
9. Main process parameters:
(1) wash with water 1:4.
Broken solution with water 1:1.
(3) broken pulp through 1.2 ~ 1.4mm sieve hole.
(5) through screening, washing, potato residue containing starch in 35% below, which contains free starch less than 5%;The content of fiber impurity in whey was lower than 0.05%.The concentration of whey reaches 5 ~ 6 baume degree.
6 separation into the pulp concentration is 5 ~ 6 degree of baume, the pulp concentration is 20 ~ 22 degree of baume.
Vacuum filter machine emulsion concentration is 20 ~ 22be.
9 (9) after dehydration, the moisture content of wet starch was less than 38%.
The starch products contain about 13.5 percent of the water level.
10. Main technical indicators:
(1) commercial starch recovery > 96%;
Water consumption <15m3/t starch;
(3) coal consumption <0.1t/t starch;
(4) power consumption <160kwh/t starch;
(5) product quality first-class rate of more than 98%.