Title of Invention | "A PROCESS FOR PRODUCING PLANTATION WHITE SUGAR AND REFINED SUGAR SIMULTANEOUSLY FROM SUGAR CANE" |
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Abstract | 1. A process for producing plantation white sugar and refined sugar simultaneously from sugar cane comprising: (a) subjecting sugar cane juice to the known lime-sulphitation process involving heating of sugar cane juice to 65 to 70°C, addition of sulphur and lime milk, passing of sulphur dioxide gas, filtration, concentrating leading to syrup, subjected the syrup to first step of crystallization by boiling at pan station to obtain massecuite, subjecting this massecuite to seperation by centrifugation to obtain molasses and sugar known as plantation by centrifugation to obtain molasses and sugar known as plantation white sugar, subjecting molasses to two step of crystallization to prepare massecuite, curing massecuite to obtain sugar known as single cured sugar, which is washed and centrifuged as herein described to get double cured sugar characterized in that is; (b) analyzing single sugar of double cured sugar and then suitably blending and melting in hot water at 50-90°C, maintaining consistency of 60-65°C brix by regulating the addition of water, obtaining sugar melt; (c) subjecting sugar melt obtained step (b) to crystallization in vacuum pan at 55 to 70°C and vacuum of 0.2 bar to 0.1 bar by external application of low pressure steam at 0.9 bar to 1.5 bar through the steam chest of vacuum pans, obtaining massecuite referred to herein as C2R massecuite; |
Full Text | FIELD OF INVENTION This invention relates to a process for producing plantation white sugar and refined sugar simultaneously from sugar cane. BACKGROUND OF INVENTION It is known that plantation white sugar has a colour value of about 100-120 I .U. in comparison to that of refined sugar which has a colour value of less than 45 I. U. The process for producing plantation white sugar consists in crushing cane to produce juice, which is subjected to the step of purification by addition of sulphur and milk of lime. Such a treated juice is subjected to the step of evaporation to produce a syrup. The syrup is sulphated and then subjected to a first step of crystallization followed by centrifugation to produce a mother liquor and plantation white sugar. The mother liquor is subjected to a second step of crystallization and centrifugation to produce B sugar and B molasses. The B sugar is recycled to the first step of crystallization, and the B molasses is subjected to a third step of crystallization and centrifugation to produce C sugar and C molasses. The C sugar is washed in a set of centrifugals and is recycled to the first step of crystallization. The 'C' wash is recycled to C massecuite. The step for producing refined sugar having a colour value of less than 45 I.U. consists in processing raw sugar to produce a melt by dissolving in water, and treating the solution with chemicals such as carbondioxide, colour precipitant, phosphoric acid and milk of lime. The treated melt is decolourised through an ion exchange column and/or active carbon treatment to produce a fine melt and then subjected to the step of crystallization. The raw sugar which has a colour value of approximately 1000 I.U. is used as starting material for producing refined sugar. The raw sugar is produced by adopting procedure as for plantation white sugar but without the use of sulphur. As will be apparent, the known processes produced essentially only plantation white sugar which had a high colour value of 100-120 I.U. or refined sugar with a low colour value of less than 45 I.U. OBJECTS OF THE INVENTION An object of this invention is to propose a novel process for simultaneous production of plantation white sugar and refined sugar. Another object of this invention is to propose a process for production of plantation white sugar and refined sugar, which is an efficient and simple process. Further objects and advantages of this invention will be more apparent from the ensuing description. STATEMENT OF INVENTION According to this invention, there is provided a process for producing plantation white sugar and refined sugar simultaneously from sugar cane comprising: (a) subjecting sugar cane juice to the known lime-sulphitation process involving heating of sugar cane juice to 65 to 70°C, addition of sulphur and lime milk, passing of sulphur dioxide gas, filtration, concentrating leading to syrup, subjected the syrup to first step of crystallization by boiling at pan station to obtain massecuite, subjecting this massecuite to seperation by centrifugation to obtain molasses and sugar known as plantation by centrifugation to obtain molasses and sugar known as plantation white sugar, subjecting molasses to two step of crystallization to prepare massecuite, curing massecuite to obtain sugar known as single cured sugar, which is washed and centrifuged as herein described to get double cured sugar characterised in that is; (b) analyzing single sugar of double cured sugar and then suitably blending and melting in hot water at 50-90°C, maintaining consistency of 60-65°C brix by regulating the addition of water, obtaining sugar melt; (c) subjecting sugar melt obtained step (b) to crystallization in vacuum pan at 55 to 70°C and vacuum of 0.2 bar to 0.1 bar by external application of low pressure steam at 0.9 bar to 1.5 bar through the steam chest of vacuum pans, obtaining massecuite referred to herein as C2R massecuite; (d) subjecting C2R massecuite obtained by step ( C ) above to coolingor heating treatment depending upon summer or winter season, in a receiver fitted with slow speed stirring arrangement, centrifuging in a high speed centrifugal machine to separate crystals referred herein as C2R sugar, from molasses referred herein as C2R molasses; (e) determining colour value of C2R sugar as obtained by step (d) and blending it with sugar of similar/lower colour values obtained from other streams in the sugar factory, mixing the blend thus prepared with hot water at 50-90°C, regulating the addition of water to maintain consistency of 60-65°C obtaining melt referred to herein as C2R melt; (f) recycling C2R molasses obtained by step (d) by mixing it with streams known the art as B Heavy molasses or alternatively mixing it with other stream known in the art as A heavy molasses, (g) passing C2R melt obtained by step (e) through ion exchange columns to reduce the colour value of the melt to below 400 I.U. and obtaining sugar liquor herein referred to as C2R fine liquor; (h) subjecting C2R fine liquor obtained by step (g) to crystallization in vacuum pan in a manner as described in step ( c), obtaining refined massecuite referred to herein as C2R refined massecuite; (i) subjecting C2R refined masecuite obtained by step (h) above, to cooling/heating in a receiver fitted with low speed stirring arrangement and heat exchanging coil followed by centrifugation in a high speed centrifugal machine to separate sugar crystals, obtaining C2R refined sugar which is the refined sugar of present invention and C2R refined molasses; (j) recycling the C2R refined molasses thus obtained to step ( c) above; There are distinct advantages which ensue from the process of the present invention. One such advantage is that the process allows the production of plantation white sugar as well as refined sugar. Yet another disadvantage is that raw sugar used as the starting material for production of refined sugar is obtained from the process stream of plantation white sugar. Yet another advantage is that the mill for producing plantation white sugar need not be substantially modified, except for the addition thereto of certain additional apparatuses for producing refined sugar. DESCRIPTION OF FIGURES This invention will now be illustrated with accompanying figures which illustrate an embodiment of present invention and are not intended to be taken restrictively to imply any limitation on the scope of the present invention. In the accompanying figures: Fig. 1: shows the flow chart of the process of the present invention; DESCRIPTQN OF INVENTION According to this invention there is provided a process for producing refined sugar as well as plantation sugar from sugarcane, which comprises of the following steps: (i) producing C sugar and C-molasses by subjecting the crushed sugar cane juice to the known lime sulphitation process involving heating of the sugar cane juice to 65-70°C, addition of sulphur and lime milk, passing of sulphure dioxide gas, filtration, and repeated three steps of concentration and crytallisation in a vacuum pan; (ii) analyzing C single or double cured sugar for its colour value and then suitably blending and melting in hot water at 50 -90 °C. The consistency of the melt is maintained at 60 -65°C brix by regulating the addition of water; (iii) subjecting the C sugar melt as obtained above, to crystallization in vacuum pan operating at a vacuum of 0.2 bar A to 0.1 bar A and a temperature range of 55°C to 70°C preferably at 60-65°C. The crystallization is carried out by applying low pressure steam/vapours at 0.9 bar A to 1.5 bar A, externally in the steam chest of the vacuum pans. (iv) subjecting the above crystallized material hereinafter referred to as 'C2R massecuite' to cooling or heating treatment in a receiver, fitted with slow speed stirring arrangement and heat exchanging coils; (v) subjecting the treated C2R massecuite as above to centrifugation for separation of crystals hereinafter called 'C2R sugar', from the molasses herein after called 'C2R molasses' in a high speed centrifugal machine. (vi) Analyzing, as per the ICUMSA procedure, the C2R sugar to determine colour value and blending C2R sugar with sugars of similar /lower colour values from other streams in the sugar factory; (vii) mixing this blend obtained from step (vi) with hot water of 50-90°C to obtain sugar melt referred to herein as C2R sugar melt and the consistency of the C2R melt is maintained at 60-65 °C brix by regulating the addition of hot water; (viii) mixing the C2R molasses obtained from step (v) with other stream known in the art as 'B Heavy' molasses obtained from the existing white plantation sugar process or alternatively mixing with the stream known in the art as A Heavy molasses obtained from the existing white plantation sugar process; (ix) passing the C2R melt through set of columns containing ion exchange resins to reduce the colour value of the C2R melt below 400 I.U. to obtain fine liquor herein after called C2R fine liquor; (x) subjecting the C2R fine liquor to crystallization in vacuum pan operating at a vacuum of 0.2 bar A to 0.1 bar A and a temperature range of 55°C to 70°C preferably at 60-65°C. The crystallization is carried out by applying low pressure steam/vapours at 0.9 bar A to 1.5 bar A, externally in the steam chest of the vacuum pans; (xi) subjecting the above crystallized material herein after referred to as 'C2R refined massecuite' to cooling or heating treatment in a receiver fitted with slow speed stirring arrangement and heat exchanging coils; (xii) subjecting the treated C2R refined massecuite as above to seperation of crystals herein after called C2R refined sugar from the molasses herein after called C2R refined molasses in a high speed, centrifugal machine; (xiii) recycling the C2R refined molasses to the step (ii); The invention will now be illustrated with a working example which is intended to illustrate working of invention and is not intended to be taken restrictively to imply any limitation on the scope of the present invention. WORKING EXAMPLE 1.9 tons of C single/double cured sugar was melted in 0.8 tons of hot water and 0.4tons dust sugar was also melted in 0.44 tons of water and mixed. This melt was crystallized in a vacuum pan along with 0.58 tons of C2R refined molasses solids to produce 2.87 tons solids of C2R massecuite, which was then centriftiged to yield 1.80 tons solids of C2R sugar and 1.08 tons solids of C2R molasses. 1.08 tons solids of molasses thus obtained was recycled to B heavy molasses whereas 1.80 tons of C2R sugar was melted with 0.97 tons of hot water at 75°C to produce 2.77 tons of C2R melt which was passed through ion exchange columns to obtain C2R fine liquor of 388 I.U. colour. 2.77 tons of C2R fine liquor thus obtained was crystallized to obtain 1.80 tons solids of C2R refined massecuite, which was further centrifuged to obtained 1.22 tons of refined sugar and 0.58 tons solids of refined molasses. 0.58 tons solids of refined molasses was recycled to C2R Massecuite. It is to be understood that the process of the present invention is susceptible to modifications, changes, adaptations by those skilled in art. Such variant embodiments employing the concepts and features of the present inventions are intended to be within the scope of the present invention, which is further set forth under the following claims: WE CLAIM: 1. A process for producing plantation white sugar and refined sugar simultaneously from sugar cane comprising: (a) subjecting sugar cane juice to the known lime-sulphitation process involving heating of sugar cane juice to 65 to 70°C, addition of sulphur and lime milk, passing of sulphur dioxide gas, filtration, concentrating leading to syrup, subjected the syrup to first step of crystallization by boiling at pan station to obtain massecuite, subjecting this massecuite to seperation by centrifugation to obtain molasses and sugar known as plantation by centrifugation to obtain molasses and sugar known as plantation white sugar, subjecting molasses to two step of crystallization to prepare massecuite, curing massecuite to obtain sugar known as single cured sugar, which is washed and centrifuged as herein described to get double cured sugar characterized in that is; (b) analyzing single sugar of double cured sugar and then suitably blending and melting in hot water at 50-90°C, maintaining consistency of 60-65°C brix by regulating the addition of water, obtaining sugar melt; (c) subjecting sugar melt obtained step (b) to crystallization in vacuum pan at 55 to 70°C and vacuum of 0.2 bar to 0.1 bar by external application of low pressure steam at 0.9 bar to 1.5 bar through the steam chest of vacuum pans, obtaining massecuite referred to herein as C2R massecuite; (d) subjecting C2R massecuite obtained by step ( C ) above to coolingor heating treatment depending upon summer or winter season, in a receiver fitted with slow speed stirring arrangement, centrifuging in a high speed centrifugal machine to separate crystals referred herein as C2R sugar, from molasses referred herein as C2R molasses; (e) determining colour value of C2R sugar as obtained by step (d) and blending it with sugar of similar/lower colour values obtained from other streams in the sugar factory, mixing the blend thus prepared with hot water at 50-90°C, regulating the addition of water to maintain consistency of 60-65°C obtaining melt referred to herein as C2R melt; (f) recycling C2R molasses obtained by step (d) by mixing it with streams known in the art as B Heavy molasses or alternatively mixing it with other stream known in the art as A heavy molasses, (g) passing C2R melt obtained by step (e) through ion exchange columns to reduce the colour value of the melt to below 400 I.U. and obtaining sugar liquor herein referred to as C2R fine liquor; (h) subjecting C2R fine liquor obtained by step (g) to crystallization in vacuum pan in a manner as described in step ( c), obtaining refined massecuite referred to herein as C2R refined massecuite; (i) subjecting C2R refined masecuite obtained by step (h) above, to cooling/heating in a receiver fitted with low speed stirring arrangement and heat exchanging coil followed by centrifugation in a high speed centrifugal machine to separate sugar crystals, obtaining C2R refined sugar which is the refined sugar of present invention and C2R refined molasses; (j) recycling the C2R refined molasses thus obtained to step ( c) above; 2. A process as claimed in claim 1 wherein said crystallization is carried out at 60-65°C. 3. A process for producing plantation white sugar and refined sugar simultaneously from sugar cane as herein substantially described and illustrated herein. |
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604-del-2002-correspondence-others.pdf
604-del-2002-correspondence-po.pdf
604-del-2002-description (complete).pdf
Patent Number | 223007 | ||||||||||||
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Indian Patent Application Number | 604/DEL/2002 | ||||||||||||
PG Journal Number | 44/2008 | ||||||||||||
Publication Date | 31-Oct-2008 | ||||||||||||
Grant Date | 02-Sep-2008 | ||||||||||||
Date of Filing | 03-Jun-2002 | ||||||||||||
Name of Patentee | SUNIL SINGHAL | ||||||||||||
Applicant Address | M-48, II FLOOR, MARKET GREATER KAILASH II, NEW DELHI-110 048, INDIA. | ||||||||||||
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PCT International Classification Number | C13D 3/10 | ||||||||||||
PCT International Application Number | N/A | ||||||||||||
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