SU881489A1 - Unit for drying fibrous materials - Google Patents

Description

(54) INSTALLATION FOR DRYING FIBROUS MATERIALS

The invention relates to a drying technique and can be used in chemical, light and other industrial sectors in installations for drying fibrous materials, for example staple fiber. Installations for drying fibrous materials are known, which contain a heater for air preheating, two air-type drying chambers located in series and a receiving cyclone 1. However, it is not possible to dry high-moisture fibrous materials in these installations, since the skimmer intended for feeding materials into the drying chamber does not work when high moisture fiber enters it. In addition, installations for drying fibrous materials are known that contain a system of swinging collectors of hot air 2. However, for high capacity dryers operating with a high initial moisture content of the material, the use of a system of swing collectors is difficult, since the extension of the working area of the sheller requires an increase in length collectors, which, in turn, reduces their strength and reliability during operation. Installations for the drying of fibrous materials are known, which contain.-Sequentially installed drying and conditioning chambers, heaters mounted in front of the drying chamber, and a horizontal conveyor. Both chambers of the installation consist of separate sections, each of which is equipped with axial fans, directing heated air to the nozzle ducts placed in each section above the horizontal conveyor and below it. However, these settings have a low mass transfer rate. the last sections of the drying chamber. In addition, due to the uneven thickness of the fiber layer on the belt and the circulating air flow, part of the fiber is not blown by warm air and leaves the dryer with a high moisture content. Installations of this type occupy large production areas and have a high energy load 4. The closest proposed facility is a plant for drying bulk and fibrous materials, containing successive dryers, a drying chamber in a suspended state, and a separation chamber with inlet and outlet nozzles 4.

However, this installation does not provide drying of fibrous materials with an initial humidity of 70-100%. It is almost impossible to create a fluidized bed in a high-moisture material due to the high adhesion of wet fibers. In addition, the known structure of the separation chamber does not provide a clean separation of air and dry fiber.

The goal of the invention is to improve the quality of drying and productivity.

This goal is achieved by the fact that the drying chamber in a suspended state is made in the form of telescopically connected cylindrical shells, the inlet pipe of the separation chamber is inserted inside it along the vertical axis, and the output one is located radially in the upper part of the chamber, which is additionally equipped with a filter mesh installed above the output section an inlet nozzle, the dryer being made in the form of a perforated plate conveyor with heaters.

The drawing shows the proposed installation.

The installation contains a dryer 1 with a perforated lamellar conveyor 2 and heaters 3 for heating air, roller pittel 4, fan 5, -heater 6, which supplies material to the drying chamber in a suspended state, consisting of telescopically connected cylindrical shells 7, an intermediate fan 8, a separation chamber 9 with a filtering screen 10, a vortex-type cooling chamber 11 with tangentially arranged nozzles 12 for introducing cold air. The chamber 9 has an inlet 13, inserted inside it on a vertical axis and an outlet 14 located radially in the upper part of the chamber.

The installation works as follows.

The fibrous material enters the dryer 1 on the perforated conveyor 2. Moving together with the conveyor 2, the material is blown from top to bottom with hot air pumped by a fan (not shown in the drawing). As a result, most of the moisture is removed. Next, the material through the feeder 4 and the fan 5 enters the chamber formed by the shells 7, where, in a suspended state and gradually moving

from the bottom up, it is dried with hot air heated in the heater 6. The fiber movement in the working zone of this drying chamber occurs in a layer whose height is controlled by the aerodynamic regime and is equal to about 3/4 of the height of the chamber. This ensures an adequate residence time of the material in the chamber and an intensive mass transfer. The working area of the chamber can be changed by changing the position of the shells. The deposited material is fed through an intermediate fan 8 into the separation chamber 9 through nozzle 13. In the separation chamber 9, the mixture of air and fiber loses speed, and part of the material enters directly into the cooling chamber 11, and the rest goes to the upper part of the separation chamber 9 and settles on the filter screen 10, and the air passes through the fiber layer and the screen and then through the radially located pipe 14 is removed to the atmosphere. The grid 10 is located above the outlet section of the nozzle 13. The fiber is poured onto the grid 10 until the weight of the adhered fiber layer does not exceed the forces of its resistance moving air through it. When the force of gravity is greater than the resistance forces, the layer falls off separate camera 9, and the process is repeated. In the chamber 11, the cold air is supplied by means of tangentially located nozzles 12, which ensures the cooling of the material in a vortex flow.

The technical effect of the invention is that the described installation provides, in comparison with the known, better drying process of fibrous materials and reliable separation of fiber and air, reduces production space and energy consumption.

Claims (4)

1. Authors certificate of the USSR 26 at 17/10, 1964. 193359, cl. F 2. Authors certificate of the USSR 26 V 17/04, 1974. 523259, cl. F 3. Authors certificate of the USSR 26 V 13/20, 1958, 110757, cl. F 4. The author's certificate of the USSR 26 At 17/10, 1963. 157275, cl. F