Application Of Dryer In Printing And Dyeing Industry

< p > > a href= "//www.sjfzxm.com/news/index_c.asp" > printing and dyeing enterprise < /a > the sewage produced during the production process is discharged after reaching the standard (COD<50~60). Sludge generated in the sewage treatment process is inevitable.

The sludge in the printing and dyeing enterprise has high organic carbon content, and how to deal with the sludge is plaguing the printing and dyeing enterprises. < a href= "//www.sjfzxm.com/news/" > printing and dyeing > /a > the sludge of the enterprise (QDW calorific value) is about 1500kcal/kg ~ 4400kcal/kg.

After dewatering, the sludge can be granulated or incinerated after the drying of the rotary dryer, so that the outlet problem of the sludge can be solved.

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< p > dehydration < /p >

< p > sludge incineration must meet two conditions: 1. Dry matter content is >70%; second, sludge must be granular.

Only when the above two conditions are met can sludge be burned most economically.

Too high moisture content of sludge may extinguish combustion and block sludge is difficult to incinerate.

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< p > sludge thermal drying < /p >

< p > thermal drying of sludge after mechanical dewatering is a Guan Jian process with less than a href= "//www.sjfzxm.com" > sludge treatment < /a > utilization.

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< p > before discussing various drying technologies, we will briefly analyze the changes of sludge properties during sludge drying.

German engineer Karl Belting analyzed the distribution of water in the sludge: interstitial water, the external water content between the sludge masses is adhesive water, adsorbed water, empty siphon water, rainbow water absorption, capillary rainbow absorbing internal water, cell fluid (hydrated water content, internal rainbow water absorption).

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< p > most of the interstitial water outside the water can be separated by mechanical dehydration. Most of the internal water can only be separated by drying.

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< p > here is a major feature of sludge drying. With the drying process, the sludge will enter a gelatinous stage, also known as "viscous stage". At this stage, the dry matter content of sludge is 45 to 60%.

At this time, the sludge will stick on the wall of the dryer, resulting in the reduction of drying efficiency and even damage to the equipment.

The rotary dryer has solved this problem through the corresponding technical measures and design.

Printing and dyeing enterprises generally use heat pfer oil boiler, rotary disc dryer as long as the heat pfer oil pipe connection can be used, without additional equipment can make the sludge to meet the burning requirements.

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< p > structure of rotary dryer, < /p >

< p > rotary dryer is mainly composed of stator (shell), rotor (turntable) and driving device.

The central axis of the rotor is the bearing part of the drying turntable. It is a hollow shaft, and all turntables are welded on the hollow shaft.

The inner cavity of the central shaft is communicated with all the inner plates of the turntable, and a propulsion / agitator is arranged at the edge of the turntable, and is driven by a motor.

Each turntable is welded by two pairs of buckled discs.

The inner cavity of the turntable can pass through the heat conducting oil to convey the heat needed by the chemical.

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< p > < a href= "//www.sjfzxm.com > > rotary dryer < /a > function < /p >

< p > through the action of the propellant / agitator on the edge of the turntable, the sludge is pported uniformly and slowly through the dryer and dried through the thermal contact with the turntable.

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< p > during the drying process, the hot steam is discharged out of the machine through the exhaust pipe.

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< p > turntable dryer characteristics < /p >

Contact drying (indirect drying, heat conducting medium and sludge direct contact) is not only suitable for semi drying of sludge, but also for sludge drying technology, and the use of flexible equipment system has low oxygen content, and the possibility of dust explosion is eliminated. Even if the feed is uneven, it can ensure smooth operation and firm structure, durable and durable rotor speed is low, wear is small, maintenance is little, and continuous operation is good. The design is compact and the heat pfer area is very large. The space between the equipment and the plant space is the smallest compared with other driers.

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< p > sludge drying process < /p >

< p > according to the different purposes of final disposal of sludge, it can be semi dried or completely dried.

Rotary dryer is often used in conjunction with incinerators, and semi - converted sludge can be self - contained incineration without auxiliary heat source.

The heat generated by the sludge can meet the heat balance and optimum utilization of the dryer.

Because no additional energy is needed, the operation cost of the whole system is very low.

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< p > rotary dryer application example < /p >

< p > Wuxi Jiangsu < a href= "//www.sjfzxm.com" > Xiangshan printing and dyeing < /a > and Shandong Jining Ruyi printing and dyeing Co., Ltd. after the sewage treatment, the sludge is dewatered through the filter press, and the sludge is sent to the rotary dryer.

The sludge after drying is directly sent to the oil burning boiler. After being tested by Shandong Jining Ruyi printing and dyeing Co., the sludge calorific value is 4400kcall/kg, and the heat quantity of sludge in Jiangsu Xiangshan printing and dyeing Co., Ltd. is more than 1800kcall/kg.

After being burned and contaminated, the organic matter was completely decomposed, and the problem of sludge harmless treatment was solved.

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< p > at present, under the continuous improvement of laws and regulations on environmental protection, the harmless treatment of sludge after sewage treatment is receiving more and more attention from the whole society.

Rotary dryer is highly praised for its flexibility and high quality, especially its low investment and safe operation. It is praised by Shandong Jining Ruyi printing and dyeing Co. Ltd. and Jiangsu Wuxi Xiangshan printing and dyeing Co., Ltd.

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