Background technology:
Now, liquid glucose clarifying method in sugar refinery mainly is to adopt two kinds of sulfurous method or carbonatation process, and their clarification mechanism adds milk of lime exactly in liquid glucose, feed SO then
2Or CO
2Gas, therefore, unslaked lime is the finings that the most generally use in sugar refinery, it produces multiple important chemical reaction in syrup.In the clarification operation, lime is that the mode by milk of lime adds sugarcane juice, and SO
2Thereby, phosphoric acid forms calcium sulfite precipitation and calcium phosphate precipitation the colloid in the syrup, pigment absorption removed.And at present sugar refinery lime as the liquid glucose finings in the liquid glucose clarifying process is common lump lime, and its slake operation is lump lime directly to be put into add the water slake in the slaker and produce milk of lime, thereby, there is following problem:
1, because lump lime emulsification is incomplete, and soot particle is many, after reaction is serious, causes following harm:
(1) subsequent handling sugarcane juice pH raises and fluctuation, influences the syrup quality;
(2) it is excessive and form sucrose dicalcium, sucrose DFP to add ash easily, causes forming closely calcium precipitation and clarifying process is worsened;
(3) Ca (OH)
2Concentration is low, makes that precipitin reaction speed is slow, and increases the evaporation steam consumption;
(4) the residual calcium salt content height of syrup causes product ash content height, equipment pipe incrustation serious;
(5) the content height of inorganics in the syrup is made sweet rate rising thereby make, and the sugar recovery reduces;
(6) lime and SO
2Reaction is incomplete, SO
2Be not fully utilized, sulfur consumption is big.
2, owing to be block lime directly to be put into add the water slake in the slaker 4 and produce milk of lime (referring to Fig. 2), the lime slake is not thorough, and residual large quantities of lime slag causes the lime utilization ratio low, increases production cost, and causes serious environmental to pollute.
Summary of the invention:
The technical problem to be solved in the present invention is: existing ordinary student lime be used for that the clarifying sugar liquid method exists because of lime emulsification incomplete, soot particle is many, above-mentioned harm such as the liquid glucose that after reaction seriously causes is of poor quality, and the lime slake is not thorough, causes the problem that the lime utilization ratio is low, environmental pollution is serious, provides a kind of lime slake thorough, lime utilization ratio height, non-environmental-pollution can effectively improve clarifying effect, improves " a kind of method that unslaked lime is used for clarifying sugar liquid " of syrup quality.
The technical scheme that solves its above-mentioned technical problem is:
A kind of unslaked lime is used for the method for clarifying sugar liquid, comprise slake, add milk of lime, in and operation, it is characterized in that: described slake operation is to be that 50~300 purpose powdery unslaked limes mix the milk of lime that 8~20Be is made in stirring with water with granularity.
Above-mentioned powdery unslaked lime and water blended ratio are calculated as with ratio of weight and number: powdery unslaked lime: water=1: 2~1: 10, the temperature of water is: 40 ℃~70 ℃.
The present invention's it " a kind of method that unslaked lime is used for clarifying sugar liquid " compares with existing method, and following beneficial effect is arranged:
One, can improve clarifying effect, improve the syrup quality, can reduce production costs again.
1, precipitin reaction speed is fast, and after reaction significantly reduces, thereby reduces the evaporation steam consumption, can improve clarifying effect, can reduce production costs again.
Because the raw material of the inventive method slake operation is that granularity is the powdery unslaked lime of 50~300 order micron number magnitudes, the powdery quicklime particles is little, has big specific surface, thus in water slake apace, keep higher Ca (OH)
2Concentration, and milk of lime is fresh, and make: 1. precipitin reaction speed is fast, and effect of settling is good, and alleviates after reaction; 2. SO
2The specific absorption height, sulphur utilization ratio height; 3. the concentration of the clear juice in the stove drying and back was unlikely low, alleviated the burden of evaporization process, thereby reduced the evaporation steam consumption, can improve clarifying effect, can reduce production costs again.
2, the lime slake is thorough, has improved the utilization ratio of lime, reduces the consumption of lime, reduces cost.
Because it is the powdery unslaked lime making milk of lime of 50~300 order micron number magnitudes that the inventive method adopts granularity, the powdery quicklime particles is little, specific surface area is big, the area that contacts with water is big, thereby fast with the speed of response of water, reduce or avoided the residual of slake lime particle not, improved the utilization ratio of lime, thereby reduced the consumption of lime, reduced production cost.
3, improve clarifying effect, improve the syrup quality.
Because the raw material of slake operation employing granularity is 50~300 order micron number magnitude lime powders in the present invention's the method, lime powder is slake, reaction fast, thereby be easy to grasp and control the best ash amount that adds, avoid causing to form CaSO closely owing to adding excessive sucrose dicalcium, the sucrose DFP of forming of ash
3, Ca
3(PO
4)
2Or CaCO
3Precipitation and clarifying process is worsened.
On the other hand, because the raw material of slake operation employing granularity is 50~300 order micron number magnitude lime powders in the present invention's the method, lime powder is slake, reaction fast, do not exist because of the bad and residual lime particle of emulsification, the slake of avoiding lagging behind raises sugarcane juice pH value or fluctuation, syrup is reached fast and keep stable p H, avoid the hysteresis slake liberated heat of residual lime particle to have a strong impact on the sedimentation of sugarcane juice simultaneously, the quality and the clear juice that guarantee syrup are settled stable, reduce the decomposition of the calcium content and the reducing sugar of clear juice.
4, add ash and be easy to control, production smoothing
In the liquid glucose clarifying process, in and pH control very important, manually operated fluctuation is bigger.Because of the raw material of slake operation in the inventive method is a pulverulent lime, be easy to realize adding the automatic control of grey process, make to add grey process stabilization that the pH fluctuation is little, can improve boiling house recovery, reduces the molasses productive rate; But while save operation cost.
Closed Circulation in Sugar Production is particularly clarified workshop section will accelerate the material processing, shortens residence time of material as far as possible, reduces conversion loss and bad variation in the production process.Fresh in the inventive method owing to milk of lime, milk of lime and SO
2The energy rapid reaction, the deposit seeds settling velocity that obtains is fast, has shortened the residence time of material in the settling vessel, thereby can avoid sugarcane juice to transform loss and bad variation, thereby improves boiling house recovery; Simultaneously, because the minimizing of after reaction, precipitation has reduced the content of inorganics in the syrup fully, makes sweet coefficient thereby reduce, and has improved the rate of recovery.
Two, the present invention's method can be improved the working environment of workers, preserve the ecological environment, and has the good social benefit.
1, improve the working environment of workers: tradition is lump lime with common lime as finings, needs the artificial slaking apparatus that adds, work under bad environment, and labour intensity is big, and more seriously lime damages people's respiratory system and skin easily.And the present invention's method can adopt airtight basin to store and interpolation automatically because the raw material of slake operation is Powdered unslaked lime, and the workman need not directly to contact with lime, avoids the injury of lime to the people, avoids the generation of occupational illness.
2, preserve the ecological environment: common block lime is difficult to complete slake; a part lime be not made into milk of lime and and lime mud discharge together; not only make the lime utilization ratio low; waste is serious; running cost rises; and can cause the bulking effect of lime mud stockyard occurrence of large-area, and influence clearing of lime mud, cause the pollution of environment.Powdered lime is little because of particle, and specific surface area is big, and the lime slake is thorough, and the main component of slake part is not CaCO
3Particle, these particles need not to discharge and can directly add in the syrup, clarifying process and subsequent handling are not produced detrimentally affect.Because no lime mud row has avoided clearing of lime mud to external environment, the more important thing is the pollution of having avoided environment.
Three, using method is easy.
Because the raw material of slake operation of the present invention is a powdery unslaked lime, thereby, be easy to realize adding the automatic control of grey process, simultaneously, because described slake operation is to be that 50~300 purpose powdery unslaked limes mix stirring and make milk of lime with water with granularity, milk of lime must not filter can add use, and using method is easy.
Below, reach embodiment in conjunction with the accompanying drawings the present invention's's it " a kind of method that unslaked lime is used for clarifying sugar liquid " technical characterictic is further described.