Chemical-free processes and methods of neutralisation, clarification, purification and decolourisation for sugar manufacturing and correlated effluents

Abstract

The process, method and system for treating and purifying sugar-based mixtures involve providing a liquid form of a sugar-based mixture and filtering it through a liquid-solid separator using a filter aid bed with a specific mean pore size and density This process produces filter cake and sugar juice. The process engages neutralisation, clarification, purification and decolourisation in a single step process with zero retention time for treatment by mechanical means. The pH of the sugar- based mixture can be increased while passing through the filter aid bed. The method may also include steps of providing a liquid-liquid separator after the liquid-solid separator and crystallisation after the liquid-liquid separator. The sugar-based mixture can be selected from various sources, and the liquid form can be produced by employing various techniques.

Description

CHEMICAL-FREE PROCESSES AND METHODS OF NEUTRALISATION, CLARIFICATION, PURIFICATION AND DECOLOURISATION FOR SUGAR MANUFACTURING AND CORRELATED EFFLUENTSTECHNICAL FIELD

[0001] Certain embodiments of the invention relate to the field of sugar processing, specifically to a method and system for treating and purifying sugar- based mixtures. Certain embodiments of the invention focus on the scientific and engineering aspects of the process, including the use of a liquid-solid separator with a filter aid bed of specific mean pore size and density, the adjustment of pH levels, and the incorporation of a liquid-liquid separator and crystallisation steps. Certain embodiments of the invention also involve the use of various filter aids and membranes for separation and the potential application of the method to different types of sugar-based mixtures. Certain embodiments of the invention further include the production of the liquid form of the sugar-based mixture using various techniques and the potential use of the system for the same. In preferred embodiments, the invention relates to a 100% chemical-free sugar production engaging neutralisation, clarification, purification and decolourisation optionally in a single step process with close to or zero retention time for treatment of “raw juice” in “ambient temperature conditions” by mechanical means.BACKGROUND OF THE INVENTION

[0002] The global industrial sugar market is continuously growing at a substantial rate owing to increasing demand for confectionary, cereal, dairy, and bakery applications. Sugarcane is the main sugar producing crop, with a world sugar production approximately six times bigger than from sugar beet, the other major source of sugar. The growth of the agro-food industry, which has resulted in thehigh production of cane sugar has also shown a positive impact on the sugar production industries.

[0003] Sucrose and natural occurring impurities in sugarcane, sugar beet or sweet sorghum is influenced by complex combination of environmental variables; natural elements in soil, temperature, soil water deficits, variety of seeds used for plantation, fertilisation, harvesting and timely processing of the harvest. Sugarcane juice directly from the mill screen contains field dirt, cane wax, fatty acids, bagacillo and other impurities. This juice typically has an ambient temperature of 20° to 40° C. The juice streams from the pressing rolls or diffuser and falls through the air several feet as the juice temperature lowers to ambient temperature. No artificial heating of the juice is needed or desired. This fresh juice will have a pH of 4.0 to 5.5. There is a natural cleavage in the fresh juice between sugar and nonsugar impurities and if this cleavage is not disturbed by process conditions, the impurities may be removed from the juice largely by physical means so that water white juice is produced containing mostly sugar and water. This water white juice is then evaporated to produce pure white sugar by crystallization, or liquid sugar. By-products of commercial value are produced from the impurities removed from the juice.

[0004] In the simplest terms, clarification is defined as a separation of solids from liquids or liquids from liquids. The success of a clarification process depends on the correct application of theories of precipitation, coagulation and flocculation. The aims of the clarification process in the sugar factory are to remove suspended solids and colloidal particles, remove non-sugar soluble impurities (e.g., proteins and polysaccharides) and raise the pH in order to minimise inversion of sucrose during subsequent processing. Clarification with chemicals and / or additives affects juice filterability, evaporator heat transfer coefficients, sucrose crystallisation and the quality and quantity of sugar produced. It therefore affects the colour, crystal morphology, crystal content, ash, and polysaccharide content of sugar. As clarification is the hub of sugar processing, sugar juice must be clarified with minimal retention time to avoid colour formation and sucrose inversion losses dueto the oxidation of some of its components and enzymatic action. In the conventional process and method, the clarification of sugar juice occurs by coagulation, flocculation and precipitation of colloids and pigmented substances, which are eliminated by changing the pH, using chemical reagents, polymers or through heating. The process consisted of adjusting the pH to between 7 and 10 and adding chemical products (coagulating agent and clarification) associated with heating. A process that also involves addition of milk of lime, sulphur and / or phosphoric acid, and use of bagacillo, clarifier and mud vacuum filter to later remove those admixtures in a process that takes between 1 to 3 hours to achieve clarified juice for further downstream processing of syrup and crystallisation.

[0005] The production of sugar from either sugarcane or sugar beet is an energy intensive process. Currently, in the sugarcane milling industry, there has been substantial interest in finding effective technologies to be applied in the removal of impurities from sugar juice during the manufacturing process. These efforts reflect the increasing demand for food products that contain minimal amounts of chemicals and, consequently, emphasis has been placed on improving the quality of the sugar, providing a white crystalline substance whilst developing chemical-free processes.

[0006] The conventional process for producing crystal and raw sugar from sugarcane involves the extraction of sugarcane juice from the harvested sugarcane. Further, sugarcane juice is submitted to purification, also commonly known as clarification, and finally resulting in crystal sugar or raw sugar. The raw sugar can be remelted to give sugar syrups or sugar liquors, which are the raw material used to produce the refined sugar after crystallisation. And conventional processes for clarification of sugarcane juice are based on defecation, sulphitation, phosphatation or carbonatation of sugar juice or solutions.

[0007] In the process of sulphitation, the process involves the introduction of sulphur dioxide (SO2) into the sugarcane juice to separate non-sugar constituents, including colouring elements. The sugar produced by this process may contain about 20 ppm or more of sulphur and this contaminant causes health andenvironmental problems and becomes difficult to be accepted in food and beverage markets.

[0008] The phosphatation processes are described in "Cane Sugar Handbook" edited by J. C. P. Chen. The process of phosphatation involves reacting the sugar solution, lime and phosphoric acid. The precipitate formed is removed by aerating the solution and skimming the particulate material from the surface of the solution. Whereas the process of carbonatation involves reacting in the sugar solution, lime and carbon dioxide. The precipitate is removed from the solution by filtration.

[0009] It is now almost universal for raw sugar refineries to use either carbonatation or phosphatation processes to clarify the melt liquor. These chemicalbased processes, as well as removing the finely divided particles of insoluble and semi-colloidal matter, also eliminate significant amounts of colour and other nonsucrose impurities which would otherwise have to be removed at greater expense in the subsequent decolorization or crystallization processes.

[0010] Clarification of sugarcane juice before crystallization is complex phenomenon, which includes steps of removal of primary solid matters like fibres, colour removal, removal of insoluble solids having poor floatability characteristics, removal of secondary precipitation formed due to the addition of chemicals, removal of ash generated during the melting process, stopping formation of inverted sucrose.

[0011] The US Patent 3,698,951, as well as WO 2011 / 060168 and US Patent 5,865,899 describe a sugar refining processes wherein sugar syrups and liquors are decolourized by adding dialkyldimethyl quaternary surfactants.

[0012] Whilst phosphatation generally achieves a decolouration in the range of 25-30%, the addition of these colour precipitants or cationic surfactants as disclosed in above articles, increases the efficiency of colour removal to a high level of about 70%.

[0013] Further, powder or granular activated carbon (PAC or GAC) or iron exchange resin (IER) is a commonly used substance for decolourization and impurity removal in sugar processing operations.

[0014] Therefore, many chemical additives and high temperature steps have been suggested in the prior art to precipitate impurities during the production of sugar. In view of the above, up to now there is no solution for improving the clarification process of sugarcane juice / beet sugar juice, raw syrup or melt to obtain crystal or raw sugar without addition of any chemical treatment agent.

[0015] By way of further background, aspartame is an artificial (synthesized chemical) non-saccharide sweetener that has been used for decades and is about 200 times sweeter than regular table sugar. It was approved by the U.S. Food and Drug Administration in 1974 for use as a tabletop sweetener and as an additive in chewing gum, cold drinks, breakfast cereals and for foods. Recently, the WHO said on July 2023 it was now classifying aspartame, an artificial sweetener commonly used in soft drinks, as "possibly carcinogenic to humans". So, there is currently the possible imposition of a ban of said artificial chemical base sweeter in food or allowed in smaller concentration, but health risk for human / animal life will be always there if not avoided even in small concentration. So, natural sweetener i.e. sugar obtained from sugar cane, beet root will be the only safer and healthier choice for food and cold drink manufacturing companies for sweetener selection. Therefore, in the context of these recent developments, there is an even greater importance of achieving a chemical free sugar process which is in certain embodiments of the invention developed to address this need of the industry.SUMMARY OF THE INVENTION

[0016] In a first broad independent aspect, the invention provides a process for treating sugar-based mixtures for production of white or refined sugar, comprising the steps of: providing a liquid form of a sugar-based mixture; filtering the liquid mixture through a liquid-solid separator using a filter aid bed, optionally comprisingbagasse ash and / or fly ash, having a specific mean pore size between 6 to 30 micron and density between 160 to 300 kg / m3; whereby filter cake and clarified sugar juice are produced; and submitting clarified sugar juice to one or more evaporators. In preferred embodiments, the density is measured at ambient temperature.

[0017] This configuration is particularly advantageous as in certain embodiments, the process is a fully mechanical separation process which utilizes no chemicals.

[0018] This configuration is also particularly advantageous as in certain embodiments, the process may be a wholly mechanical separation process with a single chemical-free step whereby the liquid mixture is neutralised by increasing the pH from 4 to 7, clarified by removing impurities above 01 to 0.5 microns, purified by removing organic and / or inorganic impurities and the decoloured as the sugar-based mixture passes through the filter aid bed.

[0019] In a subsidiary aspect in accordance with the broadest independent aspect, the process comprises the further step of filtering the clarified sugar juice through a liquid-liquid separator using one or a succession of membranes which are configured to increase the Brix of the sugar juice prior to being submitted to said one or more evaporators. In preferred embodiments, the liquid-liquid separator is provided to act on clarified sugar juice at ambient temperature.

[0020] This is particularly advantageous as it reduces the required heating for producing sugar at the requisite high Brix values discussed herein.

[0021] In a further subsidiary aspect, the or each membrane increases the Brix of the sugar juice to reach a Brix of sugar juice of 19 to 65.

[0022] This configuration is particularly beneficial as it reduces the prior art requirement of heating the clarified liquid prior to evaporation.

[0023] In a further subsidiary aspect, the or each membrane is at least partially of ceramic material.

[0024] This configuration is particularly advantageous in handling liquid-liquid mechanical separation.

[0025] In a further subsidiary aspect, the clarified sugar juice is submitted to a juice heater prior to being submitted to the or each evaporator.

[0026] This configuration is particularly advantageous because due to the provision of the mechanical liquid-liquid separators the requirement for heating is significantly reduced and in certain embodiments is not required prior to entry into the evaporators.

[0027] In a further subsidiary aspect, the process further comprises the step of neutralising the pH from 4 to 7 of the sugar-based mixture whilst passing through the filter aid bed.

[0028] This configuration is particularly advantageous as it can in certain embodiments do away with any requirement for the chemical treatment of the mixture to achieve neutral pH.

[0029] In a further subsidiary aspect, the filter aid bed is configured to remove impurities from 0.1 to 0.5 microns whilst the liquid mixture passes through the filter aid bed.

[0030] This configuration is particularly advantageous as it avoids employing in certain embodiments chemicals to remove impurities as the removal may be effective using a wholly mechanical separation process.

[0031] In a further subsidiary aspect, the step of filtering the liquid mixture arises before any heating of the liquid mixture.

[0032] In a further subsidiary aspect, the process further comprises a step of crystallisation after the liquid-liquid separator.

[0033] This is particularly advantageous in achieving a wholly chemical free process from raw material to crystallisation.

[0034] In a further subsidiary aspect, the filter aid bed comprises a precoat filter layer disposed on a porous support means. In a further embodiment, the precoat filter layer may comprise a homogeneous ceramic layer whereas the porous support means may incorporate granules or a particulate layer comprising filter aids as in any of the aspect mentioned herein.

[0035] In a further subsidiary aspect, the filter aid bed comprises filter aids selected from one or a mixture of the following: siliceous volcanic rock, amorphous silicate, diatomaceous earth, expanded perlite, solkafloc, fly ash, bagasse ash, activated carbon, graphite, graphene, microcrystalline cellulose, cellulose fibre, bentonite, diatomite, oxidised graphite, oxidised graphene, agricultural fibres, saw dust, rich hull ash, paper fibres.

[0036] In a further subsidiary aspect, one or more of the filter aids are combined with lime.

[0037] In a further subsidiary aspect, the process further comprises the step of evaporation to obtain solid sugar crystals having sugar colour between 100 IU to 10 IU.

[0038] In a further subsidiary aspect, the or each membrane comprises one or more of the following: silicon carbide, activated carbon, graphite, graphene, oxidised graphite, and oxidised graphene; optionally the pores range from 600 to 1200 Daltons.

[0039] In a further subsidiary aspect, the or each membrane comprises sintered steel with cross-flow internal titanium pores ranging from 0.0001 to 0.02 microns.

[0040] In a further subsidiary aspect, the sugar-based mixture is selected from sugarcane juice, sugar beet juice, sweet sorghum juice, com sugar syrup, sugar solutions, raw sugar melt, and solutions of said substances.

[0041] In a further subsidiary aspect, the liquid form is produced by employing one or more of the following or a combination thereof: rotary juice screen, mixedjuice filter, melting, boiling, fluid stimulator, filtration, addition of milk of lime, dilution, oxidation, ozonation.

[0042] In a further broad aspect, the invention provides a system for treating sugar-based mixtures configured to carry out the process of any one of the aspects mentioned hereinbefore or hereinafter.OVERVIEW OF THE DESCRIPTION

[0043] In one embodiment, the present invention may provide a 100% chemical- free processing of white or refined sugar and effluents thereof. In preferred embodiments, the application relates to 100% chemical-free preprocessing of “plantation” white or refined sugar and effluents thereof. In preferred embodiments, the process is a chemical-free and zero retention process technology and method with zero liquid or solid waste discharge.

[0044] The main goals of a sugarcane or sugar beet factory are to have an efficient profitable operation with the required sugar quality and maximum sugar recovery. Therefore, in certain embodiments, the invention may provide the clarification, purification and decolourising processes to supply sugar juice and / or sugar solutions of optimum quality to the back end of the factory, and of solutions of substance or effluents produced thereafter.

[0045] In a further embodiment, the invention may propose a chemical free process to produce any form of sugar; crystal, raw sugar, refined sugar, liquid sugar, castor sugar with no chemical impurities and thus, acceptable for human consumption or by the food, pharmaceutical and beverage industries.

[0046] In a further embodiment, another objective of the present invention is to provide a chemical-free and zero retention time clarification process technology and method for manufacture of white sugar or refined sugar or any form of sugar and treatment of correlated derivative products with zero liquid or solid waste.

[0047] Since colour is one of the most important sugar quality criteria, this aspect has come under evaluation and in certain embodiments of the present invention, the methods reduce the sugar colour below 100 IU and even very low colour of 10 IU that too without a trace of chemicals in the final product.

[0048] In certain embodiments, the present invention eliminates the steps as well as time of the entire conventional process and method [equipment] of clarification station comprising of; Mill of Lime, Defecation, Sulphitation, Phosphatation or Carbonatation, Clarifier and Mud Vacuum Filter, or melt clarification, filtration or decolourisation for sugar juice or of raw sugar refining.

[0049] Embodiments of the invention may relate to a chemical-free processes, methods of neutralizing, clarification, purification and decolourisation, in a single step, for sugar manufacturing and solutions of substance thereof. Embodiments of the invention may also relate to chemical-free processes for the treatment of effluents. More preferably, embodiments of the invention relate to a process and method for producing chemical-free sugar crystals or derivative products from sugar cane, sugar beet or refining of raw sugar or sweet sorghum. Further, embodiments of the invention may eliminate the major costly and time-consuming steps of conventional processes generally followed for clarification of sugar solutions, solutions of substance and all kinds of effluents. In certain embodiments, the method of the invention eliminates the following process steps: sulphitation, defecation, carbonation, phosphatation which are ineffective as well as chemicalbased techniques. Certain embodiments offer instead sustainable specialized processes and methods of reliability, high throughput, and accessibility for sugar and by-products manufacture.

[0050] Certain embodiments of the invention produce sugar without any chemicals otherwise employed by panela, defecation, sulphitation, phosphatation or carbonatation process for clarification of sugar juice, sugar solution, sugar or molasses to produce derivative products, such as; ethanol, alcohol, industrial spirits etc.

[0051] Certain embodiments of the invention provide a chemical free process and methods for industries, like; sewage, water treatment, edible oils, fossil fuels, beer, pulp and paper, corn syrup, fruit juices, fructose, glucose, starch or any industry requiring liquid-solid or liquid-liquid separation.

[0052] In certain embodiments, the present invention may reduce the retention time of neutralization, clarification, purification and decolourisation of sugar-based mixture or by-products or effluent of sugar manufacturing and integrated industries.

[0053] In certain embodiments, the present invention short-circuits the conventional process steps of neutralization, clarification, purification and decolourising of sugar-based mixture or effluent of sugar manufacturing and integrated industries.

[0054] In certain embodiments, the invention is to use as a filtering medium, a neutralising special grade of adsorptive filter aid suitable either alone or in combination of material to increase the pH of sugar juice or other selective grade of filtering medium and which is highly efficient with respect to removal of suspended matter and other inherent impurities, turbidity, viscosity and colour in the fluid being filtered and, which furthermore, permits of a greatly increased rate of flow.

[0055] In a further embodiment, the invention clarifies the sugar juice, sugar solution, solutions of substance, liquids or effluents with zero retention time.

[0056] In a further embodiment, the system employs a filtering device which employs the hereinabove described filtering medium through depositing to desired thickness of the filter- aid or other filtering medium upon the filtration zone as one of the operating elements thereof and provide a novel and highly efficient method of filtration.

[0057] In a further embodiment, the system employs a fluid stimulator to alter the molecular structure of sugar juice, sugar solution, solutions of substance, liquids or effluents.

[0058] In a further embodiment, the system clarifies sugar juice from the mill screen or diffuser to a water white clarity before heating said juice.

[0059] In a further embodiment, the system clarifies unheated juice by mechanical means without chemicals. In a preferred embodiment, the system comprises physical filtration means.

[0060] In a further embodiment, the system is configured to remove impurities, reduce viscosity and colour in sugar juice in steps so as not to prevent filtration by an accumulation of gelatinous materials.

[0061] In a further embodiments, the system clarifies sugar juice without destroying the natural cleavage between sugar and impurities.

[0062] In a further embodiment, the system or method is configured to feed the clarified juice directly to juice heater and / or evaporator, the product retaining the desired composition characteristics of raw juice for production of good quality crystallised sugar.

[0063] In further embodiments, the system or method is configured to eliminate the use of bagacillo, clarifier, mud vacuum filter, milk of lime, any chemicals, such as; sulphur, phosphoric acid or other cleaning chemicals or decolourising agents.

[0064] In a further embodiment, the system or method produces liquid sugar by evaporating said juice to water white condition at a pH substantially below 7.0 to invert part of said sugar.

[0065] In a further embodiment, the system or method is configured to employ special grade and type of membrane to increase the Brix of cold or hot clarified sugar juice of 14°-18° Brix to up to and including 65° Brix.

[0066] In a further embodiment, the system or method is configured to reduce or eliminate the use of the evaporation process to boil the clarified sugar juice to produce syrup for direct feeding to vacuum pans for crystallisation and curing for production of good quality sugar.

[0067] In a further embodiment, the system or method are configured to eliminate or reduce the scale formation in tubes in the evaporators or other prime movers.

[0068] In a further embodiment, the system or method is configured to produce refined sugar without chemicals or colour removal of clarified melt by ion exchange resin, powdered activated carbon or granular activated carbon.

[0069] In a further embodiment, the system or method short-circuits the conventional process and method for production of panela, rapadura, jaggery, white sugar, refined sugar or liquid sugar or any form of sugar from sugar cane or sugar beet or corn sugar syrup or sweet sorghum.

[0070] In a further embodiment, the system or method to clarify effluents from the sugar and distillation processes to produce water without treatment or chemicals.

[0071] In a further embodiment, the system or method provides other by-products of value from the filtered sugar juice; also to improve methods of treating sugar juice in other respect.

[0072] In a further embodiment, the system or method is applicable and of great value to all industries where filtration, clarification or dehydration form a part of the process; that is, in sugar juice, fruit juice, syrup clarification, water or sewage, process effluents, edible oil, fossil fuels, beer, paper and textile... and many more. The described process prepares a filter so that efficient filtration is effected from the beginning of the filtration operation with the liquid to be treated, and will thoroughly remove all gummy and sticky substances, suspended solids and otherinherent impurities, turbidity, viscosity, colour etc., and especially in the case of sugar juice, interfere with subsequent crystallisation.

[0073] In a further embodiment, the system or method provides sugar juice, solution or solution of substance without traces of lime that otherwise form as hard (calcite) scale in evaporator tubes and reduces the heat transfer coefficient and increase the boiling time and frequent tube cleaning cycles leading to reduced evaporation rate.

[0074] In a further embodiment, the system or method employs chemical-free filtration and treatment of effluents from sugar manufacturing, ethanol or alcohol distillery for production of water for recycling back to the process.

[0075] In a further embodiment, the system or method may eliminate the use of other forms of effluent treatment plant.

[0076] In a further embodiment, the system or method comprises a process and method of filtration and treatment to eliminate the discharge of liquid or solid wastes.

[0077] Cane sugar juice has always been considered nonfilterable because of the highly gelatinous impurities which it contains. However, in certain embodiments of the invention, cane juice directly from the mill screen may be readily filtered, in its ambient temperature, with a high flow rate which is sufficient and appropriate with the use of a filter aid.

[0078] In an embodiment, the present invention provides a chemical free process and methods of neutralisation, clarification, purification and decolourisation of sugar-based mixture or effluent of sugar, ethanol, alcohol or industrial spirit manufacturing industries, comprising the step of: step 1) providing a liquid form of solution to be treated, step 2) clarifying the liquid mixture through a solid-liquid separator using a filter aid bed having specific a mean pore size between 6 to 30 micron and a density between 160 to 300 kg / m3at ambient temperature.

[0079] In a further embodiment, the pH of the sugar-based mixture is adjusted between 4 to 7 by passing through said filter aid bed.

[0080] In a further embodiment, the system is provided with or the method provides a liquid-solid separator selected from a filtration system having appropriate grade of filter aid or a combination of materials or other filter mediums or equipment depending on the size of impurities and viscosity and specific flow characteristics and filter aids are selected from siliceous volcanic rock / amorphous silicate, diatomaceous earth, expanded perlite, Solkafloc, fly ash, bagasse “fly” ash, activated carbon, graphite, graphene, microcrystalline cellulose, bentonite, diatomite, oxidised graphite, oxidised graphene, agricultural fibres, saw dust, rich hull ash, paper fibres and a combination thereof.

[0081] In certain embodiments, this system or method removes many of the impurities contained in the juice, such as field dirt, cane wax, a tarry matter, bagacillo, colour etc., which are found in the filter cake. The juice is now filtered to produce a transparent juice.

[0082] Wherein, in certain embodiments, the effluent of sugar manufacturing industries is selected from juice, syrup or molasses for ethanol, alcohol or industrial spirit production.

[0083] In certain embodiments, the system or method comprises pre-treatment or post- treatment steps for the solution to be treated. These pre-treatment or posttreatment steps include filtration from rotary juice screen, mixed juice screen, melting, boiling, fluid stimulator, filtration, addition of milk of lime, dilution, ozonation, oxidation or combination thereof.

[0084] In further embodiments, the system or method comprises the further steps after clarification selected from liquid-liquid separation system to sucrose concentration having brix of this juice is increased to up to and including 65° through membranes. This juice may be heated for sterilization and coagulate albumin value between 13° to 18° to obtain a concentrated solution. Evaporationto obtain solid sugar crystals having sugar colour between 100 IU to 10 IU. Optionally followed by evaporation step in the conventional way to produce pure white direct sugar of below 100 IU and light-coloured edible molasses. Further, the liquid-liquid separation system and evaporation can be used in combination or independently either with or without evaporation.

[0085] In further embodiments, the liquid-liquid separation system is selected from membranes of appropriate material and types for liquid-liquid separation to increase the Brix of sugar juice up to and including 65° in ambient or preheated temperature condition.

[0086] It is commercially desirable to remove non-sugar contaminants from a sugar juice or sugar syrup thus a need exists for a chemical-free process to eliminate the defecation, sulphitation, phosphatation or carbonatation steps to eliminate nonsugar components early in the process before these components adversely affect the colour and quality of sugar juice, sugar solutions or of the crystallised sugar.

[0087] More preferably, certain embodiments relate to a process and equipment for chemical-free and zero retention time clarification process technology and method for manufacture of white sugar or refined sugar and treatment of correlated derivative products with zero liquid or solid waste discharge.

[0088] In certain embodiments, the system or method comprise a clarification process and method of filtration which may include filters of the type which employ special grade of adsorptive filter-aid, either alone or in combination with other materials and methods [equipment], as a filtering material and the use of a fluid stimulator to alter the molecular structure of liquids, sugar juice, sugar solutions, solutions of substance and effluents.

[0089] In certain embodiments, the method may include a chemical free process and methods of neutralisation, clarification, purification and decolourisation of sugar-based mixture or effluent of sugar, ethanol, alcohol or industrial spirit manufacturing industries, comprising step of:Step 1) providing a liquid form of a sugar-based mixture;Step 2) filtering the liquid mixture through a liquid-solid separator using a filter aid bed, optionally comprising bagasse ash and / or fly ash, having a specific mean pore size between 6 to 30 micron and density between 160 to 300 kg / m3at ambient temperature; whereby filter cake and clarified sugar juice are produced; and,Step 3) filtering the clarified sugar juice through a liquid-liquid separator using membranes of appropriate material and types for liquid-liquid separation to increase the Brix of sugar juice up to and including 65° at ambient temperature.Step 4) Optionally followed by evaporation to obtain solid sugar crystals having sugar colour between 100 IU to 10 IU.

[0090] In certain embodiments, the system or method is configured so that the pH of the sugar-based mixture is adjusted between 4 to 7 passing through said filter aid bed.

[0091] In one of the embodiment, the step of filtering the liquid mixture through a liquid- solid separator is a single step chemical-free process and method of neutralising the pH from 4 to 7, clarifying by removing impurities above 0.1 to 0.5 microns, purifying by removing organic and / or inorganic impurities and the decolouring of the sugar-based mixture while passing through the said filter aid bed. Wherein said filter aid bed comprising precoat filter layer disposed on a porous support means.

[0092] And in one more embodiment, the step of filtering the liquid mixture through a liquid-solid separator to perform a separate step for neutralising the pH from 4 to 7, removing impurities above 0.1 to 0.5 microns and removing organic and / or inorganic impurities of the sugar-based mixture whilst passing through one or more filter aid beds.

[0093] The present invention also provides a system for treating sugar-based mixtures using chemical-free mechanical separation process for production of white or refined sugar, comprising: a means for obtaining a sugar based mixture; a liquid-solid separator using a filter aid bed optionally comprising bagasse ash and / or fly ash, having a specific mean pore size between 6 to 30 micron and density between 160 to 300 kg / m3 at ambient temperature; whereby filter cake and clarified sugar juice are produced; and, one or more liquid-liquid separators comprising membranes of appropriate material and types for liquid-liquid separation to increase the Brix of clarified sugar juice up to and including 65° at ambient temperature.Optionally the said system comprising means for evaporation and crystallisation after a liquid-liquid separator.

[0094] In certain embodiments, the system or method is configured wherein a solidliquid separator is selected from the filtration system having appropriate grade of filter aid or a combination of materials or other filter mediums or equipment depending on the size of impurities and viscosity and specific flow characteristics and filter aids are selected from siliceous volcanic rock / amorphous silicate, diatomaceous earth, expanded perlite, solkafloc, fly ash, bagasse “fly” ash, activated carbon, graphite, graphene, microcrystalline cellulose, bentonite, diatomite, oxidised graphite, oxidised graphene, agricultural fibres, saw dust, rich hull ash, paper fibres and combination thereof.

[0095] Further, the concentration of the filter aid may be from 0.1 to 99.99 % w / w and may be combined with other filter aids.

[0096] In a further embodiment, a system or method provides a pre-treatment for sugar cane juice, sugar beet juice and sweet sorghum juice. The pre-treatmentmethods can be selected from the technique of rotary juice screen, mixed juice filter, melting and boiling.

[0097] In one or more embodiments of the present invention, the fluid stimulator is employed for altering the molecular structure of liquids, sugar solutions, solutions of substances, effluents passing through magnetic field of appropriate strength to de-cluster the molecules to improve chemical, physical, bacteriological, viscosity or scale forming quality and allow significant homogenization to the downstream process.

[0098] In a further embodiment, after passing the juice through a fluid stimulator, the solution is subjected to a liquid-solid separator, wherein a liquid-solid separator is a filtration system having an appropriate grade of filter aid or a combination of materials or filtration medium or equipment depending on the size of impurities and viscosity and specific flow characteristics.

[0099] The solid cake obtained in the above process is suitable and safe for animal feed as no chemical is used therein. In a further subsidiary aspect, the juice extract of above process is subjected to liquid-liquid separation. In a further subsidiary aspect, water is removed from the solution by passing the solution through a membrane system under pressure or vacuum. In a further subsidiary aspect, the membranes selection is based on appropriate material and types for liquid-liquid separation in ambient temperature condition to increase the Brix of sugar juice up to and including 65° in ambient or preheated temperature condition.

[0100] In a further embodiment, the system or method produces direct white sugar below 100 IU or liquid sugar or refined sugar below 45 IU or jaggery or panela or rapadura from the sugar juice or sugar solutions without chemicals or refining.

[0101] Considering most of the above, the following aspects are further emphasised:• 100% chemical-free production of sugar and treatment of correlated effluents, engaging neutralisation, clarification, purification and decolourisation, all in a single step process with zero retention time, and zero liquid or solid discharged;• Liquid-solid separation (use of filter-aid with emphasis of use of Bagasse Fly Ash with option to use the other specified materials (mainly expanded perlite and “phosphoric acid method” activated carbon as alternatives), besides others that we included as an added protection to avoid others from employing the same technique. Quite frankly put, the use of any other filteraid will incur costs of purchase and disposal compared to Bagasse Fly Ash which is readily available at source free-of-charge and be disposed in the manner as practiced thus not generating additional solid waste.• Liquid-liquid separation (in preferred embodiments this process does not involve filter-aid, but employs a ceramic membrane)• Treatment of domestic and industrial effluents - here we will need to employ expanded perlite and / or “phosphoric method” activated carbon

[0102] In preferred embodiments, the emphasis is on the 100% chemical-free process with the use of a rotary drum vacuum precoat filter, a pressure filter or any filtration system with the use of an appropriate filter-aid.BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

[0103] Figure 1 shows a flow chart of an embodiment of the invention when applied to a sugarcane milling process.

[0104] Figure 2 shows a flow chart of an embodiment of the invention when applied to a sugar beet diffusion process.

[0105] Figure 3 shows a flow chart of an embodiment of the invention when applied to a raw sugar refining process.DETAILED DESCRIPTION OF THE INVENTION

[0106] Certain embodiments of the invention relate to a chemical-free processes and methods of neutralising, clarification, purification and decolourising for sugar manufacturing and solutions of substance thereof. Further embodiments relate to chemical-free processes for effluents treatment. Certain embodiments relates to the process and method for producing a chemical-free sugar crystals or derivative products from sugarcane (see figure 1), sugar beet (see figure 2) or refining of raw sugar (see figure 3). Other embodiments may include corn sugar syrup or sweet sorghum.

[0107] Certain embodiments of the invention relate to a process and to equipment for chemical-free and zero retention time clarification process technology and methods for manufacture of white sugar or refined sugar and treatment of correlated derivative products with zero liquid or solid waste discharge, that is notably different from prior application both in process and function [method]. Embodiments of the invention relate to clarification processes and methods through filtration, and more particular to filters of the type which employ special grades of adsorptive filter-aids, either alone or in combination with other materials and methods [equipment], as a filtering material and the use of fluid stimulator to alter the molecular structure of liquids, sugar juice, sugar solutions, solutions of substance and effluents.

[0108] Embodiments of the invention relate to a process and method for chemical- free and zero retention time clarification process for spent wash / vinasse effluent from the distillation process for production of renewable energy and recyclable water with zero liquid or solid discharge.

[0109] In accordance to an embodiment, the system or method relates to a process and method for sugar production wherein the process comprises the following options:Fluid stimulators to alter the molecular structure of liquids, sugar solutions, solutions of substances, effluent etc.• Filtration using appropriate grade of filter aid or a combination of materials or other materials or equipment depending on the size of impurities and viscosity and specific flow characteristics for liquidsolid separation with or without pre-treatment of feed materials in ambient or preheated temperature condition to increase fluidity and achieve high filtration yield for production of white sugar below 100 IU or even very low to 10 IU;• Membranes of appropriate material and types for liquid-liquid separation in ambient temperature conditions to increase the Brix of clear sugar juice up to and including 65° in ambient or preheated temperature condition for production of white sugar below 100 IU or even very low to 10 IU;• Filtration of raw sugar melt for production of refined sugar below 45 IU.• Filtration using appropriate grade of filter aid or a combination of materials or equipment for treatment[clarification] of effluents from the sugar process for conversion to water to recycle in the process or for use in any other purpose.• Filtration of using appropriate grade of filter aid or a combination of materials or other materials or equipment for treatment of effluents from distillery for conversion to water to recycle in the process or for use in any other purpose.

[0110] In a conventional process, the cane juice from the mill screen is heated to boiling and limed. The cane wax which has a melting point of 80° C, melts when the juice is heated and disperses throughout the juice. Other impurities, such as fatty acids and coloured bodies, also melt and disperse throughout the juice. Mud is separated from the juice by settling clarifiers, and the resulting clarified juice is almost dark brown. The juice has been ruined by the premature heating. This clarified juice is evaporated and inevitably produces raw or white sugar and black strap molasses of commerce. This raw sugar is usually shipped to a distant refinerywhere it is remelted and reprocessed to produce refined sugar which is sold to the consumer. The black strap molasses contains 30 percent sucrose which cannot be crystallized and 30 percent natural invert sugar, all of which is largely wasted due to the low price of black strap molasses. The entire process is inefficient and wasteful.

[0111] The prior art system and process of the production of crystallised sugar from sugarcane or beet or refined sugar is well known. Furthermore, the development of equipment and associated processes for producing sugar has been extensive. Generally, sugar products are produced from a naturally occurring liquid contained within the cells of sugarcane stalk or sugar beet. There are various methods used in clarification, all designed to remove impurities employing either defecation, sulphitation, phosphatation or carbonatation processes.

[0112] The conventional processes for manufacturing sugar are associated with drawbacks like microbial growth at different stages of the sugar juice processing and high energy requirement for sugar refining. Further, the conventional double sulphitation leads to heavier fouling of the heating surfaces, increased residual sulphur, and producing higher ash content in the so obtained sugar. Further, the additional cost is required to process the plantation white sugar or raw sugar obtained by the conventional process, in order to obtain the refined sugar or the further downstream process of production of ethanol, alcohol or spirits.

[0113] Furthermore, in the conventionally known processes, the mud drawn from the bottom of the clarifier is filtered through a rotary vacuum drum filter and the filtrate juice is then added back to the process thus increasing the burden on the clarification process.

[0114] It is not unknown that presence of sulphur dioxide in sulphited sugar has several respiratory related health hazards, besides adverse effects in downstream process of production of ethanol, alcohol, industrial spirits from use of sulphited syrup, massecuites or molasses. Additionally, sugars cleaned with sulphur releasessulphur dioxide during the storage process, which is yet another undesirable effect of such sugars.

[0115] To overcome the aforementioned drawbacks, the system and method has been configured to be a chemical-free process and method for manufacturing sugar and derivative products.

[0116] Embodiments of the invention are shown in figures 1 to 3, where a liquidsolid separation is shown as a primary step and an optional liquid-liquid separation as a secondary step of clarifying sugar solutions and solutions of substance or effluents at its ambient temperature in a more efficient, economical and expeditious process and method without the use of chemical reagents, polymers or decolourising processes. Therefore, in certain embodiments, the invention eliminates most if not all trouble-giving processes which are common place in the prior art, namely; defecation, sulphitation, phosphatation carbonation, melt clarification, melt filtration and melt decolourisation.

[0117] Figure 1 shows an embodiment of the invention when applied to sugar cane mills generally referenced 1. The sugar cane is submitted initially to a rotary juice screen 2 from which a mixed juice 3 is extracted at a typical pH value of 4.7 to 5.5. The mixed juice is then subjected to a chemical-free liquid-solid separation process. It includes a mechanical separation process reliant on the mixed juice filtering through a filter aid which is suitable to retain impurities whilst allowing the clear juice to exit from the mechanical separator 4. The mechanical separator 4 comprises a particulate filter aid including a bed through which the juice passes. The filter aid bed, in preferred embodiments comprises bagasse ash and / or fly ash, having a specific mean pore size between 6 to 30 micron and density between 160 to 300 kg / m3; whereby filter cake and clarified sugar juice are produced. The filter aid bed is configured to remove impurities from 0.1 to 0.5 microns whilst the liquid mixture passes through the filter aid bed. In certain embodiments, the filter aid bed comprises filter aids selected from one or a mixture of the following: siliceous volcanic rock, amorphous silicate, diatomaceous earth, expanded perlite, solkafloc,fly ash, bagasse ash, activated carbon, graphite, graphene, microcrystalline cellulose, cellulose fibre, bentonite, diatomite, oxidised graphite, oxidised graphene, agricultural fibres, saw dust, rich hull ash, paper fibres. In a preferred embodiment, the filter aid bed comprises a precoat filter layer disposed on a porous support means.

[0118] The filter cake may be processed separately from the clarified sugar juice. The resulting clear juice possesses a Brix of 13 to 18 and a pH 7 significantly having avoided prior art chemical stages involved in clarification and the prior art chemicals for increasing the pH. The clear juice 5 is all the more remarkable as it is suitable for either directly being subjected to evaporators to obtain crystalline sugar or may be subjected to a juice heater 6 before being subjected to the evaporators 7. The resulting crystalline sugar may have a Brix of up to and including 65 without requiring any chemicals. In order to further improve the process, alternatively the clear juice may be subjected to a secondary mechanical separation stage to achieve liquid-liquid separation through one or more separators 8. Instead of necessarily having a filter aid bed as in the liquid-solid separator previously described, the liquid-liquid separator possesses one or a succession of membranes which are configured to increase the Brix of the sugar juice prior to being submitted to said one or more evaporators 7. In a further embodiment, the juice exiting the liquid-liquid separator may potentially also be submitted to a juice heater. This embodiment of employing the liquid-liquid separator yields in any event a significant reduction in the heating and evaporation energy demands. The or each membrane of the liquid-liquid separator increases the Brix of the sugar juice to reach a Brix of sugar juice of 19 to 65. In preferred embodiments, the or each membrane is at least partially of ceramic material. In certain embodiments, the or each membrane comprises one or more of the following: silicon carbide, activated carbon, graphite, graphene, oxidised graphite, and oxidised graphene; optionally the pores range from 600 to 1200 Daltons. In further embodiments, the or each membrane comprises sintered steel with cross-flow internal titanium pores ranging from 0.0001 to 0.02 microns. The result of this embodiment is high quality sugarwith a Brix of up to and including 65 with in preferred embodiment zero use of chemicals and with a significant reduction in the energy required to obtain crystalline sugar. In a preferred embodiment, the high quality sugar has a Brix of 55 to and including 65

[0119] Figure 2 shows an embodiment of the invention when applied to sugar beet cossettes generally referenced 11 and diffusion generally referenced 12. In a first step, a thin juice 13 is extracted at a typical pH value of 5.5 to 6.5. The thin juice is then subjected to a chemical-free liquid-solid separation process. It includes a mechanical separation process reliant on the mixed juice filtering through a filter aid which is suitable to retain impurities whilst allowing the clear juice to exit from the mechanical separator 14. The mechanical separator 14 comprises a particulate filter aid including a bed through which the juice passes. The filter aid bed, in preferred embodiments comprises bagasse ash and / or fly ash, having a specific mean pore size between 6 to 30 micron and density between 160 to 300 kg / m3 at ambient temperature; whereby filter cake and clarified sugar juice are produced. The filter aid bed is configured to remove impurities from 0.1 to 0.5 microns whilst the liquid mixture passes through the filter aid bed. In certain embodiments, the filter aid bed comprises filter aids selected from one or a mixture of the following: siliceous volcanic rock, amorphous silicate, diatomaceous earth, expanded perlite, solkafloc, fly ash, bagasse ash, activated carbon, graphite, graphene, microcrystalline cellulose, cellulose fibre, bentonite, diatomite, oxidised graphite, oxidised graphene, agricultural fibres, saw dust, rich hull ash, paper fibres. In a preferred embodiment, the filter aid bed comprises a precoat filter layer disposed on a porous support means.

[0120] The filter cake may be processed separately from the clarified sugar juice. The resulting clear juice possesses a Brix of 13 to 18 and a pH 7 significantly having avoided prior art chemical stages involved in clarification and the prior art chemicals for increasing the pH. The clear juice 15 is all the more remarkable as it is suitable for either directly being subjected to evaporators to obtain crystalline sugar or may be subjected to a juice heater 16 before being subjected to theevaporators 17. The resulting crystalline sugar may have a Brix of up to and including 65 without requiring any chemicals. In preferred embodiments, a Brix of 55 to 65 is preferred. In order to further improve the process, alternatively the clear juice may be subjected to a secondary mechanical separation stage to achieve liquid-liquid separation through one or more separators 18. Instead of necessarily having a filter aid bed as in the liquid-solid separator previously described, the liquid-liquid separator possesses one or a succession of membranes which are configured to increase the Brix of the sugar juice prior to being submitted to said one or more evaporators 17. In a further embodiment, the juice exiting the liquidliquid separator may potentially also be submitted to a juice heater. This embodiment of employing the liquid-liquid separator yields in any event a significant reduction in the heating and evaporation energy demands. The or each membrane of the liquid-liquid separator increases the Brix of the sugar juice to reach a Brix of sugar juice of 19 to 65. In preferred embodiments, the or each membrane is at least partially of ceramic material. In certain embodiments, the or each membrane comprises one or more of the following: silicon carbide, activated carbon, graphite, graphene, oxidised graphite, and oxidised graphene; optionally the pores range from 600 to 1200 Daltons. In further embodiments, the or each membrane comprises sintered steel with cross-flow internal titanium pores ranging from 0.0001 to 0.02 microns. The result of this embodiment is high quality sugar with a Brix of up to and including 65 with in preferred embodiment zero use of chemicals and with a significant reduction in the energy required to obtain crystalline sugar. In preferred embodiments, the high quality sugar has a Brix of 55 to and including 65.

[0121] Figure 3 shows an embodiment of the invention when applied to raw sugar refining generally referenced 21 and a melter generally referenced 22. In a first step, a melt juice 23 is extracted at a typical pH value of 5.5 to 6.5. The melt juice is then subjected to a chemical-free liquid-solid separation process. It includes a mechanical separation process reliant on the melt juice filtering through a filter aid which is suitable to retain impurities whilst allowing the clear juice so called clearmelt 25 to exit from the mechanical separator 24. The mechanical separator 24 comprises a particulate filter aid including a bed through which the juice passes. The filter aid bed, in preferred embodiments comprises bagasse ash and / or fly ash, having a specific mean pore size between 6 to 30 micron and density between 160 to 300 kg / m3; whereby filter cake and clarified clear melt are produced. The filter aid bed is configured to remove impurities from 0.1 to 0.5 microns whilst the liquid mixture passes through the filter aid bed. In certain embodiments, the filter aid bed comprises filter aids selected from one or a mixture of the following: siliceous volcanic rock, amorphous silicate, diatomaceous earth, expanded perlite, solkafloc, fly ash, bagasse ash, activated carbon, graphite, graphene, microcrystalline cellulose, cellulose fibre, bentonite, diatomite, oxidised graphite, oxidised graphene, agricultural fibres, saw dust, rich hull ash, paper fibres. In a preferred embodiment, the filter aid bed comprises a precoat filter layer disposed on a porous support means.

[0122] The filter cake may be processed separately from the clarified sugar juice. The resulting clear melt possesses a Brix of 13 to 18 and a pH 7 significantly having avoided prior art chemical stages involved in clarification and the prior art chemicals for increasing the pH. The clear melt 25 is all the more remarkable as it is suitable for either directly being subjected to evaporators to obtain crystalline sugar or may be subjected to a juice heater (not shown) before being subjected to the evaporators 27. The resulting crystalline sugar may have a Brix of up to and including 65 without requiring any chemicals. In preferred embodiments, the resulting crystalline sugar may have a Brix of 55 to 65. In order to further improve the process, alternatively the clear juice may be subjected to a secondary mechanical separation stage to achieve liquid-liquid separation through one or more separators 28. Instead of necessarily having a filter aid bed as in the liquid-solid separator previously described, the liquid-liquid separator possesses one or a succession of membranes which are configured to increase the Brix of the sugar juice at ambient temperature prior to being submitted to said one or more evaporators 27. In a further embodiment, the juice exiting the liquid-liquid separatormay potentially also be submitted to a juice heater. This embodiment of employing the liquid-liquid separator yields in any event a significant reduction in the heating and evaporation energy demands. The or each membrane of the liquid-liquid separator increases the Brix of the sugar juice to reach a Brix of sugar juice of 19 to 65. In a preferred embodiment, there is no pre-evaporator heater. In preferred embodiments of the liquid-liquid separator, the or each membrane is at least partially of ceramic material. In certain embodiments, the or each membrane comprises one or more of the following: silicon carbide, activated carbon, graphite, graphene, oxidised graphite, and oxidised graphene; optionally the pores range from 600 to 1200 Daltons. In further embodiments, the or each membrane comprises sintered steel with cross-flow internal titanium pores ranging from 0.0001 to 0.02 microns. The result of this embodiment is high quality sugar with a Brix of up to and including 65 with in preferred embodiment zero use of chemicals and with a significant reduction in the energy required to obtain crystalline sugar. In preferred embodiments, the embodiments of figures 1 to 3 provide a zero retention time clarification process technology and method for manufacture of white sugar or refined sugar and treatment of correlated derivative products with zero liquid or solid waste discharge.

[0123] In one embodiment, the system or method incorporates a clarification process to supply sugar juice and / or sugar solutions of optimum quality to the back end of the factory, and also clarification of solutions of substance or effluents. This invention relates generally to an improved process of treating various liquids or solutions, such as sugar solutions, solutions of substance and its effluents occurring in the refining of cane and beet sugar juice, syrup, molasses, effluent, raw sugar etc. In certain embodiment, the invention relates to a process and / or method for chemical-free treatment of sugarcane, beet or raw sugar to neutralise, purify, decolorise, decalcify, increase the Brix and alter the molecular structure of the raw sugar juice or raw melt syrup during the clarification and decolourisation processed for the production of crystallised white below 100 IU or refined sugar below 45 IU with a neutralising porous precoat filter layer disposed on a porous support means.

[0124] Optionally, the precoat filter layer comprises a liquid slurry constituted by an aqueous suspension of fibrous filter aid material with a neutralising agent and employing either / or a combination of precoat, membrane or pressure filtration, ozonation and fluid stimulator as instruments [a driving medium] to achieve the removal of suspended solids and impurities, and reducing colour, turbidity and viscosity, and further treatment of correlated effluents from sugar and distillation processes to reclaim water for recycling back to the process and to also achieve zero solid or liquid discharge.

[0125] A further embodiment of the invention relates to a process and method of producing sugar products without the need for chemical clarification of raw sugar juice or melt sugar solution by either unrefined panela, defecation, sulphitation, phosphatation or carbonatation process, or the pre or post treatment of effluents.

[0126] The process and method advantageously allow the production of sugar products without post-treatment with characteristics that are closer to the target specification than the traditional pre-treatment sugar composition. A combination of sources may be used in a single embodiment.

[0127] A variety of sugar samples (sugarcane juice from rotary juice screen) were tested for final results as per method disclosed in present invention and results are tabulated in table no. 1 and 2. These trials should only be used as examples and are not meant to restrict the application of the innovation.TABLE NO.lTABLE NO. 2TABLE NO. 3

[0128] In a further embodiment, the system or the method is configured to provide for clarified sugar solutions, liquids, solutions of substance or effluents using chemical free method in a rapid and economical manner with zero retention time. In preferred embodiments, this is obtained using a special grade of adsorptive porous filter-aid alone or in combination or other materials in a preliminary operation in which a coating of filter-aid is built up on the filtering medium of the filter and then passing the liquid to be treated through the filter.

[0129] The filter-aid may be milled to produce various grades of material, each with specific characteristics with resulting particles jagged, interlocking features,which form billions of microscopic channels to yield ideal flow and particle-capture rates across a variety of applications: raw sugar juice, sugar solutions, solutions of substance, liquids or effluents.

[0130] The rate at which the filter-aid may be added to the pre-coating liquid depends upon the size of the filter, the thickness of the bed of filter- aid which it is desired to build up, the character of the liquid being treated, the rate of flow and other operating factors. The time necessary to form the precoat may vary from 5 to 15 minutes, depending upon the above factors. During the pre-coating operation it is desirable to regulate the circulation through the filter in such a manner as to give open and rapid flow. This is very desirable because a rate of flow greater than the gravitational effect on the suspended filter-aid shall effectively prevent the liquid from being retarded or from standing in the filter cells or spaces, thereby effectively preventing any classification, settling or segregation of particles of filter- aid which results in uneven heterogeneous cake formation and thereby impairs the efficiency of the filtration operation.

[0131] Advantages of certain embodiments of the invention over conventional process:• 100% chemical-free sugar products and by-products,• Removes all impurities and reduces colour, viscosity and turbidity of sugar juice or solution in cold or ambient / hot conditions,• Increase Brix of sugar juice in cold or hot conditions,• Produce good quality and quantity of sugar• Economical and user-friendly,• Less process steps,• Zero retention time,• Reduced sugar losses during clarification or in final molasses,• Less manpower,• Less steam, power and water requirements,• No chemicals or mechanical cleaning of evaporator tubes,• Enhance the distillation process for Ethanol, Alcohol or Spirits’• Improve the production of Renewable Energy• A host of other direct and indirect benefitsFURTHER ASPECTS

[0132] In a broad independent aspect, the invention provides a chemical free process and method of neutralisation, clarification, purification and decolourisation of sugar-based mixture or effluent of sugar, ethanol, alcohol or industrial spirit manufacturing industries, comprising the steps of:Providing a liquid form of solution to be treated,Clarifying the liquid mixture through a liquid-solid separator using a filter aid bed having specific mean pore size between 6 to 30 micron and density between 160 to 300 kg / m3 at ambient temperature.

[0133] In a subsidiary aspect, the system or method of adjusting the pH of the sugar-based mixture from 4 to 7 whilst passing through said filter aid bed.

[0134] In a subsidiary aspect, the chemical free process and methods as per any of the preceding aspects, wherein the sugar-based mixture is selected from sugarcane juice, sugar beet juice and sweet sorghum juice, corn sugar syrup, sugar solutions, raw sugar melt, solutions of substances.

[0135] In a further subsidiary aspect, the system or method wherein the effluent of sugar manufacturing industries is selected from either sugar juice, syrup or molasses for production of ethanol, alcohol or industrial spirit.

[0136] In a further subsidiary aspect, wherein the chemical free process and methods as per any preceding aspect, wherein the liquid form is produced by using technique selected from rotary juice screen, mixed juice filter, melting, boiling, fluid stimulator, filtration, addition of milk of lime, dilution, oxidation, ozonation or combination thereof.

[0137] In a further subsidiary aspect, the chemical free process and methods as per any preceding process, wherein liquid-solid separator is selected from a filtration system having appropriate grades of filter aid or a combination of materials or other filter mediums or equipment depending on the size of impurities and viscosity and specific flow characteristics.

[0138] In a further subsidiary aspect, the chemical free process and methods as per any preceding aspects, wherein filter aids are selected from siliceous volcanic rock / amorphous silicate, diatomaceous earth, expanded perlite, solkafloc, fly ash, bagasse ash, activated carbon, graphite, graphene, microcrystalline cellulose, cellulose fibre, Bentonite, Diatomite, oxidised graphite, oxidised graphene, agricultural fibres, saw dust, rich hull ash, paper fibres and mixture thereof and concentration of said filter aid is selected between 01 to 99.99% w / w.

[0139] In a further subsidiary aspect, wherein the chemical free process and methods as in any preceding aspect, herein the further steps after clarification selected for liquid-liquid separation system to sucrose concentration having brix value between 13° to 18° to obtain concentrated solution.

[0140] In a further subsidiary aspect, the chemical free process and methods as per any of the preceding aspects, wherein the further steps after clarification are selected from evaporation to obtain solid sugar crystals having sugar colour between 100 IU to 10 IU.

[0141] In a further subsidiary aspect, the chemical free process and methods of any of the preceding aspect, wherein liquid-liquid separation system and evaporation can be used in combination or independently either with or without evaporation.The chemical free process and methods as in any of the preceding aspects, wherein the liquid-liquid separation system is selected from membranes of appropriate material and types for liquid-liquid separation to increase the Brix of sugar juice up to 65° in ambient or preheated temperature condition.

Claims

CLAIMS1. A process for treating sugar-based mixtures for production of white or refined sugar, comprising the steps of: providing a liquid form of a sugar-based mixture; filtering the liquid mixture through a liquid-solid separator using a filter aid bed, optionally comprising bagasse ash and / or fly ash, having a specific mean pore size between 6 to 30 micron and density between 160 to 300 kg / m3; whereby filter cake and clarified sugar juice are produced; and, submitting clarified sugar juice to one or more evaporators.

2. The process of claim 1, wherein the process comprises the further step of filtering the clarified sugar juice through a liquid-liquid separator using one or a succession of membranes which are configured to increase the Brix of the sugar juice prior to being submitted to said one or more evaporators.

3. The process of claim 2, wherein the or each membrane increases the Brix of the sugar juice to reach a Brix of sugar juice of 19 to 65.

4. The process of claim 3, wherein the or each membrane is at least partially of ceramic material.

5. The process of any of the preceding claims, wherein the clarified sugar juice is submitted to a juice heater prior to being submitted to the or each evaporator.

6. The process of any one of claims 1 to 5, further comprising the step of neutralising the pH from 4 to 7 of the sugar-based mixture whilst passing through said filter aid bed.

7. The process of any one of the preceding claims, wherein said filter aid bed is configured to remove impurities from 0.1 to 0.5 microns whilst the liquid mixture passes through the filter aid bed.

8. The process of any one of the preceding claims, wherein said step of filtering said liquid mixture arises before any heating of said liquid mixture.

9. The process of claim 2, further comprising a step of crystallisation after said liquid-liquid separator.

10. The process of any one of the preceding claims, wherein said filter aid bed comprises a precoat filter layer disposed on a porous support means.

11. The process of any one of the preceding claims, wherein said filter aid bed comprises filter aids selected from one or a mixture of the following: siliceous volcanic rock, amorphous silicate, diatomaceous earth, expanded perlite, solkafloc, fly ash, bagasse ash, activated carbon, graphite, graphene, microcrystalline cellulose, cellulose fibre, bentonite, diatomite, oxidised graphite, oxidised graphene, agricultural fibres, saw dust, rich hull ash, paper fibres.

12. The process of claim 11, wherein one or more of said filter aids are combined with lime.

13. The process of any one of the preceding claims, further comprising the step of evaporation to obtain solid sugar crystals having sugar colour between 100 IU to 10 IU.

14. The process of claim 2, wherein the or each membrane comprises one or more of the following: silicon carbide, activated carbon, graphite, graphene, oxidised graphite, and oxidised graphene; optionally the pores range from 600 to 1200 Daltons.

15. The process of claim 2, wherein the or each membrane comprises sintered steel with cross-flow internal titanium pores ranging from 0.0001 to 0.02 microns.

16. The process of any one of the preceding claims, wherein the sugar-based mixture is selected from sugarcane juice, sugar beet juice, sweet sorghum juice, corn sugar syrup, sugar solutions, raw sugar melt, and solutions of said substances.

17. The process of any one of the preceding claims, wherein the liquid form is produced by employing one or more of the following or a combination thereof: rotary juice screen, mixed juice filter, melting, boiling, fluid stimulator, filtration, addition of milk of lime, dilution, oxidation, ozonation.

18. A system for treating sugar-based mixtures configured to carry out the process of any one of claims 1 to 17.

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