Rotary tube bundle dryer for alcohol feed

In the process of alcohol production, rotary tube bundle dryer is used for alcohol feed drying equipment, the use technology of rotary tube bundle dryer is important, because its use effect is related to the production of energy consumption, product quality and many other results. The rotary tube bundle dryer is independently developed in China in recent years. After years of practical use and improvement, the use technology of the rotary tube bundle dryer has been greatly improved.

In the process of alcohol production, the rotary tube bundle dryer is used for alcohol feed drying equipment, the use technology of rotary tube bundle dryer is important, because its use effect is related to the production of energy consumption, product quality and many other results. The rotary tube bundle dryer is independently developed in China in recent years. After years of practical use and improvement, the use technology of the rotary tube bundle dryer has been greatly improved.

Drying principle of rotary tube bundle dryer

A rotating tube bundle dryer is installed in a horizontal cylinder, which is composed of many heating tubes. The steam passes through the heating tube of the rotary tube bundle, and the material runs in the gap inside the horizontal cylinder and outside the tube bundle, and the material contacts the outer surface of the tube bundle core and is dried. In alcohol production transfer cylinder tube bundle dryer is used to dry feed equipment. Rotary tube bundle dryer has large production capacity, continuous operation, need to return material, easy to operate. The material is dried quickly and has high thermal efficiency. The equipment has scientific structure and wide application range. It can dry powder, granular, flake materials and materials with little viscosity. It is suitable for drying materials with water content below 45%, especially for materials with drying temperature below 150 ℃.

Brief introduction of tube bundle dryer 

Machine discharge, so as to complete the drying process. There is steam in the tube bundle of the rotary tube bundle dryer. The material is dried outside and inside the tube bundle. The heat exchange is carried out on the outer surface of the tube bundle. The waste steam generated during drying is discharged from the dehumidification cover at the discharge end of the dryer. The steam enters from one end of the rotary tube bundle and the condensate is discharged from the other end. The steam and material can be in the direction of forward or reverse flow 。 The wet material enters from one end of the rotary dryer, and is lifted to 130 ~ 165 ° by the shovel fixed on the rotary drum tube bundle, and then falls between the rotary drum tube bundles. The wet material is dried in the process of contacting with the rotary drum tube bundle. The rotating cylinder body, rotating tube bundle and material shovel belt lift and push the material forward until it reaches the discharge port at the other end. The flat shovel in the rotary tube bundle dryer turns and mixes the materials and makes the materials move in a circle. The material is transported from the feed end of the tube bundle to the discharge end by the conveying shovel, and the material is discharged from the rotary drum tube bundle dryer by the discharge shovel. The flat shovel plays an important role in the mixing state. It lifts up the materials. This kind of shovel can ensure that the materials are well distributed and evenly distributed. The evenly arranged shovel makes the materials tend to be completely mixed in the process of turning.

Working process of drum bundle dryer

the main drive motor drives the tube bundle roller to rotate through the gear transmission system. The material enters the tube bundle drum from the feeding end through the feeding screw conveyor, and then through the plate on the tube bundle drum, the material is picked up on one side and pushed forward on the other side, and pushed all the way from the feeding end

Enter into the other end of the shell to discharge. When the material enters the tube bundle roller, the steam enters into the heat exchange tube of the tube bundle from the steam inlet at the discharge end to heat the heat exchange tube. The heated pipe wall transfers heat to the dried material outside the tube wall to dry the material. The water in the material is vaporized during the drying process, and the vaporized water is discharged from the cylinder through the dehumidification mechanism. After the steam in the tube is heat exchanged, the condensate is discharged from the outlet of the rotary joint. The steam entering and discharging modes of the rotary tube bundle dryer are carried out separately in a steam system.

Heat source

The heat source of rotary tube bundle dryer is saturated steam, the pressure of heat source is 0.4 ~ 0.8 MPa, and the temperature range is 142.92 ~ 169.61 ℃. The thermal efficiency of the rotary tube bundle dryer is 65% ～ 85%, which increases with the increase of steam pressure (temperature), and is related to the inlet air volume and exhaust air volume. The main parameter to measure the production capacity of the rotary tube bundle dryer is evaporation intensity, which is the water evaporation capacity per unit time and heating area, that is, the water quantity that can be evaporated by 1 m2 heating pipe area in unit time. The drying strength of rotary tube bundle dryer is 1.6-6.2 kg / (M2 · h), which is related to the effective contact rate of materials, condensate discharge, and also varies with the properties of materials. In principle, the higher the steam pressure (temperature), the higher the evaporation intensity. The evaporation intensity of different materials is different due to the large particle size, low evaporation intensity and many components (such as fat) that are difficult to evaporate. The evaporation intensity of the rotary tube bundle dryer is also affected by the inlet air volume. Too large or too small air inlet at the feed inlet will affect its effect and steam consumption.

Related parameters and schematic diagram

3 W / (M2 · h · K). Evaporation of 1 kg of water requires 1.25-1.8 kg of steam. The circumferential velocity of the dryer is 0.7-1.3 M / s and the rotating speed is 4-10 rpm. The filling rate of materials in the rotary tube bundle dryer is relatively high, about 30% ～ 40%. The drying time of the material is 25-35 min. the residence time of the material in the dryer is adjusted according to the moisture content and drying degree of the material. The moisture content of the wet material dried by the rotary tube bundle dryer ranges from 60% to 75%, and the discharge is more than 3%. The heat consumption of rotary tube bundle dryer is 1.4 kg steam / kg water, i.e. 3500 kJ / kg water or 840 kcal / kg water. Energy consumption of rotary tube bundle dryer: 3500-3800 kJ / kg water or 840-910 kcal / kg water, equivalent to about 1.45-1.5 kg steam / kg water.