efficient disposal of harmful effluents from sugar industry

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India is the largest sugar producing country in the world. The sugar industry plays an important role in India’s economy. It is the second largest industry in the country. Sugar industry is a seasonal industry which operates for max 4-5 months a season. The industry use sugarcane as the raw product along with other various chemicals to increase the face value of the final product. Milling of cane stalks for the extraction of raw sugar yields several by-products of varying usefulness. Sugar is the main product that we receive from the sugarcane industry. These by-products include wastewater, molasses, and bagasse and mill mud. On average, each tonne of raw sugar produced yields seven tonnes of waste products. Molasses is thick, dark brown, uncrystallized juice obtained from raw sugar during the refining process and in the sugar industry is allowed to pass through a distillery then it forms ethanol. Thus we see that sugar mills even process the molasses to make ethanol. During the process a huge amount of water is also used per day and as a result industry generates waste water. Waste water is generated in a sugar mill, mill house. In the mill house it is mostly contaminated by oil and grease. The wastewater which is produced from the process house mainly results from floor and equipment washing and is highly contaminated with the additive and other chemical used at the different stages. Boiler house mainly contributes in the air pollution and have a very little share in water pollution. But the gas produced by the boiler house is treated within the factory and is then released in the air so that it does not contaminate the air. Based on the ratio a sugar mill having a capacity to crush 4500 tonnes of cane a day requires 9000 m 3 / per day Of water with the ratio 1:2 and hence the mill generates the wastewater in the range of 1800m 3 / day. The sugar mill waste water is characterized by its brown color, burnt- sugar like odor, high temperature, low pH, high ash or solid residues and contain high% of dissolved organic and inorganic matter. The waste water is again treated in the factory itself. The process of sedimentation takes place where the entire solid matter settle at the bottom and the calcium hydroxide is allowed to pass through it so that it is neutralized. Finally when the water is neutralized its color is removed and the water is recycled. The recycled water is passed through the fermentation tank for fermentation to happen. And even this water is used for irrigation. Bagasse is mainly used to fuel the mill boilers and generate electricity and mill mud or filter mud and ash are mainly used as soil ameliorants or, to lesser extent, as plant nutrients. . Bagasse is the fibrous matter that remains after sugarcane stalks are crushed to extract

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Sugar Industry is the second largest industry in the country. The industry use sugarcane as the raw product along with other various chemicals to increase the face value of the final product. Efficient disposal of harmful effluents from Sugar Industry. This documents gives you how the effluents from Sugar Industry like Molasses, Bagasse, wastewater and Mill mud are efficiently used so that it does not pollute the environment . Huge amount of electricity is generated form bagasse from the sugar industry. The waste water is again treated in the factory itself. The recycled water is even used for irrigating fields. Also sugar mills even process the molasses to make ethanol.

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Page 1: Efficient disposal of harmful effluents from Sugar Industry

India is the largest sugar producing country in the world. The sugar industry plays an important role in India’s economy. It is the second largest industry in the country. Sugar industry is a seasonal industry which operates for max 4-5 months a season. The industry use sugarcane as the raw product along with other various chemicals to increase the face value of the final product. Milling of cane stalks for the extraction of raw sugar yields several by-products of varying usefulness. Sugar is the main product that we receive from the sugarcane industry. These by-products include wastewater, molasses, and bagasse and mill mud. On average, each tonne of raw sugar produced yields seven tonnes of waste products. Molasses is thick, dark brown, uncrystallized juice obtained from raw sugar during the refining process and in the sugar industry is allowed to pass through a distillery then it forms ethanol. Thus we see that sugar mills even process the molasses to make ethanol. During the process a huge amount of water is also used per day and as a result industry generates waste water. Waste water is generated in a sugar mill, mill house. In the mill house it is mostly contaminated by oil and grease. The wastewater which is produced from the process house mainly results from floor and equipment washing and is highly contaminated with the additive and other chemical used at the different stages. Boiler house mainly contributes in the air pollution and have a very little share in water pollution.But the gas produced by the boiler house is treated within the factory and is then released in the air so that it does not contaminate the air. Based on the ratio a sugar mill having a capacity to crush 4500 tonnes of cane a day requires 9000 m3 / per day Of water with the ratio 1:2 and hence the mill generates the wastewater in the range of 1800m3 / day.The sugar mill waste water is characterized by its brown color, burnt- sugar like odor, high temperature, low pH, high ash or solid residues and contain high% of dissolved organic and inorganic matter.The waste water is again treated in the factory itself. The process of sedimentation takes place where the entire solid matter settle at the bottom and the calcium hydroxide is allowed to pass through it so that it is neutralized. Finally when the water is neutralized its color is removed and the water is recycled. The recycled water is passed through the fermentation tank for fermentation to happen. And even this water is used for irrigation.

Bagasse is mainly used to fuel the mill boilers and generate electricity and mill mud or filter mud and ash are mainly used as soil ameliorants or, to lesser extent, as plant nutrients. . Bagasse is the fibrous matter that remains after sugarcane stalks are crushed to extract their juice. It is currently used as a biofuel and in the manufacture of pulp and building materials.

The bagasse is first collected in a recovery pit and then it is passed through a grinder. After the grinding is over it is collected in a collecting tank after that it is fermented. The fermentation tank has water which is received from the waste water treatment plant. From the fermentation tank mud is formed which is used as fertilizers in farms. Mill mud is one of the by-products that are produced in significant volume.

The bagasse is further collected in a desulfurizing tube and then is passed through a gas engine power generator and is finally used to produce electricity.

The sugar industry produces significant amounts of bagasse that can be incinerated and secure a basis for own power and process heat production while delivering excess

Page 2: Efficient disposal of harmful effluents from Sugar Industry

power to the grid. Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials. Incineration and other high temperature waste treatment systems are described as "thermal treatment". Incineration of waste materials converts the waste into ash, flue gas, and heat. The ash is mostly formed by the inorganic constituents of the waste

In this way a huge amount of electricity is generated form bagasse from the sugar industry.