|Title of Invention
A METHOD FOR SIMULTANEOUS CLARIFICATION AND DECOLOURISATION OF SUGARCANE JUICE BY USING FLAT MEMBRANE ULTRAFILTRATION MODULE
|A method for simultaneous clarification and decolourisation of sugarcane juice without using any chemicals for clarification or decolourisation to alter characteristics of cane juice as received using flat membrane module comprising the steps of: Extracting cane juice from cane stock, Storing the extracted juice on continuous stirring in a container to facilitate steady withdrawal, Pumping the stored sugarcane juice into specific ultrafiltration flat membrane module configuration at a predetermined pressure and at ambient temperature, Adjusting the pressure within the specific ultrafiltration flat Membrane module configuration to fetch optimum flow of refined cane sugar; Collecting the refined sugarcane juice, Collecting the rejected stream, wherein the sugarcane juice is simultaneously clarified and decolourised.
THE PATENTS ACT. 1970
(39 of 1970)
& THE PATENS RULES, 2003
[See section 10, Rule 13]
A METHOD FOR SIMULTANEOUS CLARIFICATION AND DECOLOU-RISATION OF SUGARCANE JUICE BY USING FLAT MEMBRANE ULTRA¬FILTRATION MODULE;
GOEL PRAYAS AN INDIAN NATIONAL OF C/O. ROCHEM SEPARATION SYSTEMS (INDIA) PVT. LTD., 401/402, LAVLESH COURT PANDIT VARDE ROAD, BANDRA (WEST), MUMBAI - 400 050, MAHARASHTRA, INDIA.
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER (N WHICH IT IS TO BE PERFORMED.
FIELD OF INVENTION
The present invention relates to a method of simultaneously clarifying and decolorizing sugarcane juice using Ultrafiltration membrane.
BACKGROUND OF INVENTION
Conventionally, crystallized sucrose commonly called SUGAR is manufactured from the sugar cane juice. The quality of sugar produced from sugarcane juice depends on the quality of sugarcane juice and the process of producing the sugar from such cane juice.
The sugarcane juice is known to contain coloured impurities such as naturally occurring pigment materials including chlorophyll, anthocyanins, and flavones which impart colour to the sugar produced from such juice making it unacceptable. Further, the sugarcane juice especially the mill mixed juice often contain very fine particles such as bagacillo, which make the juice turbid that also affect the crystallization of sugar during the sugar manufacture. Therefore, the sugarcane juice should be fractionated to remove both the colored and suspended impurities to improve the quality of sugar manufactured from such juice.
Conventionally, sugar is manufactured by raw sugar process and refinery process. In the production of raw sugar, the sugarcane stalks are chopped into small pieces, which are crushed to obtain cane juice leaving behind the fibrous material called bagasse. The extracted juice is then clarified in part by screening and in part by precipitation and flocculation by heat and addition of lime. In addition, sulfur dioxide is bubbled through
the juice resulting in a bleaching effect. The clarified juice after precipitation is then thermally concentrated to produce sugar syrup. The
syrup is subjected to crystallization to precipitate sugar crystals. This slurry is centrifuged to separate sugar.
In refinery process, the raw sugar is cleaned and melted to form sugar solution, which is again clarified to remove particulate matter by filtration. The further decolourisation of sugar solution is accomplished by carbon adsorbents, such as bone char or activated carbon. Sulfur dioxide is used commonly to decolorize the sugar solution. Sometimes, ion exchange units are also used for decolourisation of sugarcane juice because of the anionic character of the colorants. The resultant sugar solution is concentrated by evaporation and then crystallized to form sugar.
The raw sugar manufacturing process followed by refining produce high-quality white refined cane sugar with a polarization of about 99.40% to 99.90%. It is a two step process which is employed even in locations where there is a sugar refinery near or even within a sugar mill.
The raw sugar manufacturing processes include double sulfitation, carbonation, phosphoflotation etc which use chemicals like sulfur dioxide, activated carbon, phosphoric acid, the residual traces of such chemicals shall be present in the sugar manufactured by such a process causing health hazards. Further, such processes use high temperature which causes inversion of cane sugar resulting in considerable loss of sugar. Also, the sugar refinery is a technologically sophisticated operation that employs equipment and numerous chemicals in order to produce refined sugar.
Further, the clarification and decolourisation is done in two steps as described above.
It was suggested that membrane technology solved the problems of using chemicals for decolonisation of sugarcane juice. US Patent Number 6479636 entitled "Sugarcane fractioning System" describes a method of extracting and purifying recombinant proteins from transgenic sugarcane. Fractionation of sugarcane juice that has been extracted from the cane stalks is obtained by using a multiple stage filtering process that uses multiple stages of decreasing porosity preferably screening followed by preferably membrane type filters, ion exchange, membrane adsorber, and chromatographic processes. However, this process using membrane type filters involves more steps and is laborious and expensive.
US Patent No. US5252350 describes a process for clarifying raw juice in which the proportion of solids in the retentate circuit of an ultrafiltration or microfiltration device is sharply increased during the starting time. With the increasing proportion of solids, the filtration yield falls off sharply and then increases again to a value which is higher than the starting value. On reaching the maximum possible filtration yield value, the proportion of solids and thereby also the filtration yield is maintained constant by regulating the amount of retentate outflow or the amount of fresh juice to be fed in. In this way the filtration yield can be significantly improved.
However, this patent does not discuss about the decolourisation of raw juice. Further it only describes more on the effective way of clarifying the raw juice to obtain significant filtration yield.
US6228178 describes a method for producing white sugar wherein nanofiltration is used to decolorize sugar juice or syrup. The resulting permeate may be used directly to crystallize white sugar without an intermediate step of producing a raw sugar, even though the color of the
permeate is substantially higher than the highest color that is acceptable in a conventionally decolorized syrup used to crystallize white sugar. Significant cost savings are thus achieved in producing white sugar. However, the patent claims that the sugar juice should be clarified before decolourisation.
Further, the membrane technology reported therein suffers from the disadvantage that the clogging of membrane takes place due to bagicillo and waxes which requires clarification before decolourisation of sugarcane juice.
The object of the present invention is to provide a method of simultaneous decolourisation and clarification of sugarcane juice at ambient temperature using a specific Flat Membrane Module.
SUMMARY OF THE INVENTION
The present invention provides a method for simultaneous clarification and decolourisation of sugarcane juice at ambient temperature without use of any chemicals for any purpose to alter characteristics of input sugar cane juice using a flat membrane module ultrafiltration configuration. The method comprises the steps of extracting cane juice from cane stock, storing the extracted juice in a container to facilitate steady flow, pumping the stored sugarcane juice into specific ultrafiltration configuration of flat membrane module ultrafilter at a predetermined pressure and at ambient temperature, adjusting the pressure within the specific ultrafiltration configuration of Flat Membrane module to fetch optimum flow of refined cane sugar. The refined juice is collected through permeate port and the rejected stream of sugarcane juice is collected through reject port of the module.
Particulate matter, colloidal particles, starch, dextrans, natural coloring material like chlorophyll, anthocyanins, and flavones and compounds responsible for viscosity, ash and colour development such as hydroxyl methyl-furfurals, dextrans, ketosylamines and the like are removed by passing the sugarcane juice through the flat membrane module at predetermined conditions. This ultrafiltration process simultaneously removes all the suspended and some of the dissolved contaminants. The sugarcane juice clarified and decolourised by this inventive method shall be used directly for the manufacture of sugar without further refinement processes. Therefore, this process completely eliminates the need for conventional clarification prior to decolourisatibn of sugarcane juice. Moreover, this method eliminates the use of chemicals including lime, sulfur, and phosphoric acid, which are used traditionally by sugar industries for clarification.
Further, this method is carried out (at) an ambient temperature unlike existing methods in which the sugarcane juice is heated resulting in loss of some portion of sugar due to its inversion.
The flat membrane ultrafiltration module used in this method is easy to clean and also it facilitates reviving the original flow rate of juice over and over again which is not possible with other membranes known in the art.
This inventive method using flat membrane module does not require separators, ion exchangers and the like methodologies which are more complicated. Therefore, this method using flat membrane module is simpler and more convenient. Further as it brings about two results in one single shot, which was hitherto not possible. It eliminates extra material
handling, extra process time and extra labor. Thus it is much an advantageous method than all of the existing methods.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
The present invention provides a method for simultaneous clarification and decolourisation of sugarcane juice using a flat membrane module configuration.
The process for simultaneous clarification and decolourisation of sugarcane juice using flat membrane module configuration includes the steps of:
Extracting cane juice from cane stock,
Storing the extracted juice in a container to facilitate steady withdrawal,
Pumping the stored sugarcane juice into specific ultrafiltration configuration of flat membrane module ultrafilter at a predetermined pressure and at ambient temperature.
Adjusting the pressure within the specific ultrafiltration configuration of Flat
Membrane module to fetch optimum flow of refined cane sugar
Collecting the refined sugarcane juice
Collecting the rejected stream,
Wherein in the foregoing steps the sugarcane juice is simultaneously clarified and decolourised.
The extraction of sugarcane juice from cane stock is done by imbibing the primarily crushed cane stalks (Primary juice) by warm water at about 50
degree centigrade to extract further more secondary cane juice to recover residual sugar (Secondary juice) from the same.
The extracted primary and secondary sugarcane juice is mixed (Mixed Juice (MJ) and stored in a stirred tank to maintain uniformity of composition and for ensuring its steady withdrawal for further steps.
The mixed juice (MJ) is then pumped into the flat membrane module ultrafilter at a predetermined pressure and temperature in order to maintain the flow rate of through said ultrafilter membrane. The pressure to pump sugarcane juice into the membrane is around one bar at an ambient temperature ranging from 20 to 50 degrees Celsius. The pressure in the membrane is maintained between 2 to 3 bars.
The flat membrane module used in the method is a Rochem flat membrane module. The molecular weight cut off characteristics of the membranes used in the module used in this invention is 8000 to 20000 with the material of membrane construction being anyone of Polyacrylonitrile (PAN); Polysulfone (PS) and Polyamide (PA). The flat membrane module is a patented module; US patent no. 6,165,361 that shows the description and working of the module.
An apparatus including the flat membrane module configuration ultrafilter (1) for carrying out simultaneous clarification and decolourisation of sugarcane juice comprises a reservoir (2) for the input mixed juice flow, a pump (3) for juice intake and pressure, a control valve (4) for controlling the flow of juice into the flat membrane module (1), a pressure gauge (5) for monitoring the input pressure, a separate port (7) for collecting the rejected stream and an outlet (8) for collecting the permeate juice.
Apparatus for carrying out simultaneous clarification & decolourisation of sugar cane juice without use of chemicals.
The invention is illustrated with example below but it does not in any way limit the scope of the invention as described above and claimed herein below.
The sugarcane juice was extracted by milling sugarcane stalks. The milled cane juice (MJ) was screened by the traditional means. The extracted cane juice i.e. Mixed Juice (MJ) is stored in a container on continuous stirring to facilitate steady withdrawal and passed through the flat membrane module at a pressure of 2 to 3 bar and at ambient temperature 20 to 50 degree Celsius continuously. The flow rate was adjusted by control valve (4) to 1000 liters per hour. The refined stream collected through the outlet (8) was analysed for turbidity and colour parameters. The comparison of initial and resultant colour values for the mixed juice and clarified sugarcane juice (CLJ) shows a surprising reduction in turbidity and colour. Table 1 shows the parameters of the mixed juice before clarification and decolourisation and table 2 shows the physical and chemical parameters after clarification and decolourisation.
1. A method for simultaneous clarification and decolourisation of sugarcane juice without using any chemicals for clarification or decolourisation to alter characteristics of cane juice as received using flat membrane module comprising the steps of: Extracting cane juice from cane stock, Storing the extracted juice on continuous stirring in a container to facilitate steady withdrawal, Pumping the stored sugarcane juice into specific ultrafiltration flat membrane module configuration at a predetermined pressure and at ambient temperature, Adjusting the pressure within the specific ultrafiltration flat Membrane module configuration to fetch optimum flow of refined cane sugar; Collecting the refined sugarcane juice, Collecting the rejected stream, wherein the sugarcane juice is simultaneously clarified and decolourised.
2. A method as claimed in claim 1 wherein the molecular weight cut off characteristics of ultrafiltration flat membrane module configuration is in the range of 8000 to 20000 MWCO and the material of construction of membrane anyone of the following viz. Polysulfone (PS); Polyacrylonitrile (PAN) and Polyamide ( PA)
3. A method as claimed in claim 1 and 2 wherein the ultrafiltration flat membrane module is Rochem Flat Membrane Module.
4. A method as claimed in claim 1 wherein the predetermined pressure for pumping the stored sugarcane juice into the flat membrane module is 1 to 2 bars.
5. A method as claimed in any of the preceding claims wherein the pressure to maintain the optimum flow within the ultrafiltration flat membrane module is 2 to 3 bars.
6. A method as claimed in any of the preceding claims wherein the said temperature is in the range of 20 to 50 degree celcius.
7. A method as claimed in any of the preceding claims wherein clarification and decolurisation occurs simultaneously.
8. A method as claimed in any of the preceding claims wherein the turbidity of the refined juice is in the range of 0 to 0.5 units.
9. A method as claimed in any of the preceding claims the colour of refined sugarcane juice is up to 3000 ICUMSA units.
10. A method as claimed in any of the preceding claims wherein the particle size of matter filtered is about 0.1 to 1.0 micron.
Dated this 21st day of January 2003
FOR GOEL PRAY AS By his Agent
|Indian Patent Application Number
|PG Journal Number
|Date of Filing
|Name of Patentee
|C/O ROCHEM SEPARATION SYSTEMS (INDIA) PVT. LTD., 401 / 402 LAVLESH COURT PANDIT VARDE ROAD, BANDRA WEST, MUMBAI - 400 050.
|PCT International Classification Number
|A 23 G 3/00
|PCT International Application Number
|PCT International Filing date