Sectional cylinder cut tobacco dryer

Abstract

The invention provides a novel energy-saving sectional cylinder cut tobacco dryer capable of arbitrarily setting the temperature in a design range to realize high-precision temperature control and high heat utilization rate. The novel energy-saving sectional cylinder cut tobacco dryer comprises a heat conducting oil circulating oil temperature controller, a drying cylinder, a hot air moisture removing system and the like, wherein the drying cylinder is divided into a feeding section drying cylinder and a discharging section drying cylinder along the feeding direction and discharging direction of cut tobaccos; and corresponding to the high-temperature zone and the low-temperature zone of the drying cylinder, the hot air moisture removing system is divided into independent high-heat air section and low-heat air section, a hot air moisture removing pipe is fixedly installed at the other side opposite to the throwing direction of the cut tobaccos without rotating together with the drying cylinder, the axial direction of an air outlet arranged on the hot air moisture removing pipe is approximately intersected with the dropping direction of the cut tobaccos, the air direction of hot air blown into the drying cylinder is intersected with the dropping direction of the cut tobaccos, and the hot air radially flows in the drying cylinder and can uniformly and effectively pass through the throwing layer of the cut tobaccos. By utilizing heat conducting oil for heating the drying cylinder and the hot air, the sectional cylinder cut tobacco dryer has high temperature control precision and heat utilization rate and can meet the process requirements of different cut tobaccos, such as processing strength, drying uniformity and the like.

Description

Technical field: [0001] The invention belongs to shredded tobacco drying equipment on a tobacco shredded production line, in particular to a segmented drum shredded drying machine for drying shredded tobacco by using hot air and heating the cylinder wall. Background technique: [0002] Shredded tobacco drying is an important process in the tobacco shredded production process. The goal of the shredded leaf drying process is to remove part of the water in the shredded leaf to meet the specified moisture requirements and accuracy, while increasing the filling value of the shredded leaf, reducing the irritation and miscellaneous gas of the shredded leaf, and improving the odor absorption of the shredded leaf. The drying process generally uses heat conduction and heat convection to heat the wet shredded tobacco, so that the moisture in the wet shredded tobacco evaporates into the barrel, and is taken out of the barrel environment with the flow of airflow inside the barrel. Purpo...

AI Technical Summary

Problems solved by technology

First of all, under the premise of ensuring the setting accuracy of the moisture content of the discharge material, it is difficult to set and control the temperature of the shredded tobacco after drying within a certain range, and the control accuracy of the shredded tobacco temperature is poor.

Second, the expansion rate of shredded tobacco cannot be set and controlled during the drying process

The third is that the drum drying machine has poor moisture control on the head and tail of the material, that is, the problem that the shredded tobacco of the batch enters the drum drying machine first and the shredded tobacco that exits the drum drying machine is too dry

First of all, the drying cylinders of various drum silk drying machines commonly used are one-stage, and the heat carrier steam used enters the arrangement tubes in the heat exchange plate of the drying cylinder from the rotary joint at the discharge end, and the steam passes through a round trip and then through the original Rotary joint discharge, because the length of the drying section is fixed, only by adjusting the amount of steam entering the drying cylinder (that is, adjusting the steam pressure) can the moisture content of the wet shredded tobacco be reduced to the requirements specified in the process, but the temperature after drying Uncontrollable, because the temperature of the drying cylinder can only be adjusted as a whole, that is to say, in the case of a stable flow of cut tobacco, the higher the moisture content of the cut tobacco, the higher the temperature of the drying cylinder, and the higher the discharge temperature, and vice versa.

In this way, it is difficult to set the temperature of cut tobacco after drying cut tobacco in a certain range.

Second, the drum drying machine is a composite drying technology. The heat exchange plate on the drum wall and the temperature of the hot air are the most important key factors to control the expansion rate of the cut tobacco. Since there is almost no temperature gradient in the length of the one-stage drying drum, it cannot be based on The expansion process of shredded tobacco needs to select the expansion temperature of the drying cylinder in a targeted manner, and the hot air must pass through the entire inner cavity of the drum no matter whether it is forward or countercurrent. Decreasing, humidity is also increasing, drying efficiency is constantly decreasing

The downstream hot air that just entered the drum dryer will play a certain role in the expansion of the cut tobacco, but it still cannot control the expansion rate of the cut tobacco

Third, there are currently many measures to control the moisture of the head and tail of the drum drying machine, such as increasing the feed amount of shredded tobacco, increasing the rotation speed of the drum, increasing the wind speed of the hot air, and reducing the pressure of the steam, etc. , but still passively solve

At present, domestic tobacco processing enterprises are also paying more and more attention to the work of energy saving and consumption reduction. At present, steam is generally used as the heat exchange carrier in drum drying machines, and the utilization rate of steam heat energy is low. A large amount of steam used by the heat exchanger of the neutralization hot air system is discharged into the environment, wasting heat and affecting the environment

The temperature of the drying cylinder is controlled by adjusting the amount of steam entering the drying cylinder (that is, adjusting the steam pressure). The pipes in the heat exchange plate cannot be filled with steam, and the temperature difference on the surface of the drying cylinder is large, which is not conducive to the effective use of heat by the shredded tobacco. Absorption, which affects the uniformity of tobacco drying

In addition, unstable factors such as steam quality, steam pressure regulation, and hydrophobic system will also seriously affect the quality of silk drying

At the same time, the supporting pipeline of the steam heat exchange system needs to be equipped with a large number of high-quality imported valves, which increases the configuration cost of the equipment

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