Sulphitation Process In Sugar Industry Pdf 11 UPD

Cane sugar production is an important industrial process. One of the most important steps in cane sugar production is the clarification process, which provides high-quality, concentrated sugar syrup crystal for further processing. To gain fundamental understanding of the physicaland chemical processes associated with the clarification process and help design better approaches to improve the clarification of the mixed juice, we explore the fractal behavior of the variables pertinent to the clarification process. We show that the major variables in this key process all show persistent long-range correlations, for time scales up to at least a few days. Persistent long-range correlations amount to unilateral deviations from a preset target. This means that when the process is in a desired mode such that the target variables, color of the produced sugar and its clarity degree, both satisfy preset conditions, they will remain so for a long period of time. However, adversity could happen, in the sense that when they do not satisfy the requirements, the adverse situation may last quite long. These findings have to be explicitly accounted for when designing active controlling strategies to improve the quality ofthe produced sugar.

Besides water, sugarcane, and reduced sugar, the mixed juice also contains many organic and inorganic nonsugar components, such as colloidal substances, inorganic salts (iron, magnesium, aluminum, calcium, etc.), and pigments. While these nonsugar components are residual nutrients in the sugarcane, they are detrimental to the sugar production. For example, flavonoids, multiacid, and organic-acid can make the mixed juice appear dark brown. Since the nonsugar components affect not only the appearance and color, but also the concentration of the sugar (i.e., reflected as the sweetness of sugar by a consumer), they have to be carefully removed. The purpose of the clarification process is to remove as many nonsugar components as possible, improve the purity of the juice, and reduce its viscosity and color values. This is critical for providing high-quality, concentrated sugar syrup crystal to the boiling stage. Therefore, the clarification stage is a key process in cane sugar production.

The remainder of the paper is organized as follows. In Section 2, we provide some details about the cane sugar clarification process, explain the various variables to be analyzed here, and discuss the challenges of analyzing those variables. In Section 3, we carry out fractal analysis of these variables using the key concept in random fractal theory, the Hurst parameter, which characterizes the basic correlation structure of the signals. Concluding discussions are presented in Section 4.

Sugar clarification is a key process in cane sugar production. It is characterized by two important indices called color value and clarity degree. Whether the color value and the clarity degree can achieve the desired or preset values can critically affect the quality of the cane sugar and the revenue of a factory.

The sulphitation method for clarification is schematically shown in Figure 1. It is a complicated physical chemical process, involving solvents such as , milk of lime and phosphoric acid. Roughly, the process can be divided into four stages, cane juice phosphorus-preliming, first heating, sulphitation-neutralization and settlement after 2nd-heating. More specifically, in the preliming stage after the first heating to 55~65°C, milk of lime and phosphoric acid are added to the mixed sugar cane juice. In the next sulphur fumigation process, gas enters the chemical process pipeline. At the end of the pipeline, milk of lime is further added for achieving neutralization, since phosphoric acid sulfite reacts with calcium hydroxide to form calcium phosphate and calcium sulfate. Then, the 2nd heating is carried out so that sugar cane colloids of mixed juice can not only fully condense in the precipitator, but also accelerate precipitation, decrease juice viscosity, and facilitate the precipitated particles to sink fast. Then, the clarified juice can come out of the settler from the top of each later, while the mud juice is discharged into the vacuum suction filter by gravity. Filtered juice can then be directly incorporated into the clear juice heating device and sent to the evaporation device to condense into syrup. Therefore, controlling the process parameters steadily is the key to improve the quality of clarified juice and sugar.

There are many excellent methods for estimating [25, 26]. In the next two subsections, we describe the methods that are most promising for detecting fractal variations in variables pertinent to the clarification process of cane sugar production.

Cane sugar production is an important industrial process. One of the most important steps in cane sugar production is the clarification process, which provides high-quality, concentrated sugar syrup crystal for further processing. To gain fundamental understanding of the physical and chemical processes associated with the clarification process and help design better approaches to improve the clarification of the mixed juice, in this paper, we have examined the fractal behavior of the 11 variables pertinent to the clarification process. We have shown that they all show persistent long-range correlations, for time scales up to at least a few days. Persistent long-range correlations amount to unilateral deviations from a preset target. This means that when the process is in a desired mode such that the target variables, color of the produced sugar and its clarity degree, both satisfy preset conditions, they will remain so for a long period of time. However, adversity could happen, in the sense that when they do not satisfy the requirements, the adverse situation may last quite long. These findings have to be explicitly accounted for when designing active controlling strategies to improve the quality of the produced sugar.

Molasses is one of the most economically important by-products of sugar industries. This has many industrial uses, viz., generation of alcohol, preparation of animal feeds, and food stuffs. Molasses containing large fractions of fermentable sugars which is diluted (three times) with good water and allowed to ferment in the presence of yeast culture (Saccharomyces cerevisae) either by batch or continuous process of fermentation. The fermentable sugars are recovered by the action of yeast as an alcohol (rectified spirit)/ethanol, leaving unfermented lower order sugars (such as dioses, trioses, tetroses, pentoses, etc.), water soluble amino acids, lignins, and other organic fractions, etc., in spentwash. The organic constituents present in higher concentration undergo reduction generating unpleasant odour.

Sugarcane industries generated wastes are organic in nature, and it has been tried to meet the nutrient requirements of various crops and cropping system as well as soil amendments. They contains significant amount of plant nutrients and organic matter improve soil properties (Jamil et al. 2008). There are two types of press mud, i.e., produced from sulphitation process, and another one is produced from carbonation process; they have different impacts on soil properties (Table 5). In sulphitation process, press mud contains nutrient and CaSO4, which is acting as a soil amendment in alkaline soils (Tiwari et al. 1998). Yaduvanshi and Yadav (1990) reported that application of sulphitation press mud not only resulted in increased crop yields, but also improved soil chemical properties. Later on, Kumar and Mishra (1991) compared the carbonation and sulphitation type of press mud on the chemical composition of soil after the harvest of rice and maize crop.

The sugar industry subsumes the production, processing and marketing of sugars (mostly sucrose and fructose). Globally, most sugar is extracted from sugar cane (~80% predominantly in the tropics) and sugar beet (~ 20%, mostly in temperate climate, like in the U.S. or Europe).

Sugar subsidies have driven market costs for sugar well below the cost of production. As of 2019, 3/4 of world sugar production is never traded on the open market. Brazil controls half the global market, paying the most ($2.5 billion per year) in subsidies to its sugar industry.[3]

The US sugar system is complex, using price supports, domestic marketing allotments, and tariff-rate quotas.[4] It directly supports sugar processors rather than farmers growing sugar crops.[4][3] The US government also uses tariffs to keep the US domestic price of sugar 64% to 92% higher than the world market price, costing American consumers $3.7 billion per year.[4] A 2018 policy proposal to eliminate sugar tariffs, called "Zero-for-Zero", is currently (March 2018) before the US Congress.[3][5] Previous reform attempts have failed.[6]

Sugar processing takes a surprising chemical journey. Initial extraction from crop plants such as sugar cane and sugar beets takes out sugars along with other dissolved compounds and fine particles. The juicing process is intended to remove pulp, but small particles will inevitably pass through the pulp screens. These non-sugar components are removed as the sugarcane juice passes through unit elements in the refining plant. Over the entire process, the solution is adjusted chemically several times to achieve stabilization, separation, and dehydration. While specific unit processes vary from plant to plant, three pH-dependent processes that are common to sugar refinement include liming, carbonation, and sulfitation. pH is crucial for these steps and continuous pH monitoring ensures complete and efficient processing.

After liming to raise the pH, the second step in sugar processing is to carbonate the sugar solution to remove the lime. This subsequently lowers the pH. It is necessary to fully remove calcium from the juice in order to avoid scaling on equipment down the line. Carbon dioxide is introduced to react with the dissolved calcium hydroxide as a result of liming and produce insoluble calcium carbonate. Even though the carbon dioxide is consumed by the reaction, dissolving carbon dioxide in water in the first place introduces excess protons thereby lowering the pH. Carbon dioxide is a readily available material as a by-product of producing burnt lime, which many factories perform on-site. Dosing carbon dioxide is trickier than dosing lime since the amount applied is not necessarily the amount dissolved. Fortunately, the extent of carbonation is reflected in the pH. The process involves staging carbon dioxide injections, where each stage involves dosing a set volume of gas and measuring the resultant pH. Once the pH drops below 9.0, all calcium will have precipitated. A final filtration step removes all suspended solids including both precipitated organics and calcium carbonate solids. 2b1af7f3a8