CN204944055U - A kind of energy-saving type vacuum drying system - Google Patents

Abstract

The utility model discloses an energy-saving vacuum drying system. After materials enter the vacuum dryer, steam from a heat exchanger enters the vacuum dryer, and the materials are dehydrated and dried under low-pressure and low-temperature conditions; the secondary steam discharged from the vacuum dryer is sprayed After the jet pump in the pump system is pressurized, it enters the heat exchanger to exchange heat with the condensed water of the heat medium; the condensed water of the heat medium is heated to form saturated water vapor and enters the vacuum dryer as the heat medium to complete the drying process of the material; the steam enters the vacuum drying After the machine heats the material, the steam condenses into water, and the high-temperature condensed water enters the heat exchanger, where it exchanges heat with the water vapor overflowing from the jet pump system, and is heated to generate water vapor, which enters the vacuum dryer cycle to complete Material drying. The energy-saving vacuum drying process and system proposed by the utility model recycles the waste heat of drying. In the system, the heat is fully utilized in stages. The entire system has high thermal efficiency, sufficient heat utilization, and low system energy consumption.

Description

An energy-saving vacuum drying system

technical field

The utility model relates to the technical field of drying, in particular to an energy-saving vacuum drying system.

Background technique

Compared with other drying methods, vacuum drying has many advantages: when drying under low pressure, the oxygen content is low, which can prevent the oxidative deterioration of the dried material, and can dry flammable and explosive dangerous goods; it can vaporize the moisture in the material at low temperature, It is easy to dry heat-sensitive materials; it can recover valuable and useful components in the dried materials; it can prevent the discharge of toxic and harmful substances in the dried materials, and it can become an environmentally friendly "green" drying, but its main disadvantage is that it needs a set that can pump water. The vacuum system of steam leads to high energy consumption, high equipment investment cost, high operating cost, low equipment production efficiency and small output. However, due to its many obvious advantages, vacuum drying has been widely used in the fields of food, chemical industry, and grain.

Utility model content

In order to solve the shortcomings of the existing technology, the utility model discloses an energy-saving vacuum drying process and system. The utility model adopts vacuum low-temperature drying and recovers the heat of the secondary steam after the drying device to improve the energy utilization efficiency of the system. The system has high drying rate and low energy consumption.

In order to achieve the above object, the concrete scheme of the present utility model is as follows:

An energy-saving vacuum drying process, comprising the following steps:

After the material enters the vacuum dryer, the saturated water vapor from the heat exchanger enters the vacuum dryer, and the material is dehydrated and dried under low pressure and low temperature;

After the saturated steam enters the vacuum dryer to heat the material, the saturated steam condenses into water, and the high-temperature condensed water enters the heat exchanger;

The secondary steam produced by the evaporation of material moisture in the vacuum dryer is injected by the injection liquid through the injection pump system, and the temperature rises after being pressurized by the injection pump, and then overflows from the injection liquid in the form of water vapor, and is separated from the injection liquid. The steam enters the heat exchanger to heat the condensed water of the heat medium. After being heated, the condensed water of the heat medium forms saturated water vapor and enters the vacuum dryer, which is used as the heat medium to complete the drying process of the material.

Further, inside the vacuum dryer, the pressure is maintained at -0.092—-0.098MPa. The vacuum dryer is equipped with a heat tracing system, which is activated when it is turned on. The pressure setting of the vacuum dryer facilitates dehydration and drying of materials at low pressure and low temperature.

Furthermore, a heater is installed in the jet pump system. Before starting the vacuum dryer, industrial waste heat or electric heating can be used to heat the spray liquid to a specified temperature. After the vacuum dryer is running, the heater is stopped. The installation of the heater is convenient for the safe operation of the whole system, and whether to turn on the heater is determined according to the operation of the system, which ensures the stability of the system.

Further, the temperature of the injection liquid of the jet pump system is higher than 100°C. After the secondary steam is injected by the jet pump, it mixes with the injection liquid. After being pressurized by the injection liquid to the back pressure of the injection pipe outlet, it overflows in the form of water vapor and enters the exchange system. The heater heats the heat medium water. By adding the jet pump system, the waste heat discharged from the vacuum dryer is better utilized, and saturated steam is generated and then returned to the vacuum dryer, which is convenient for energy recycling.

Furthermore, the material enters the vacuum dryer through the feeding device. Inside the vacuum dryer, when the temperature of the material rises to about 70°C, it is dehydrated and dried under low pressure, and the moisture content of the dried material decreases.

An energy-saving vacuum drying system, including a vacuum dryer, the inlet of the built-in heat exchange tube of the vacuum dryer is connected to the outlet of the heat exchanger through a pipeline, and the outlet of the built-in heat exchange tube of the vacuum dryer is connected to the inlet of the heat exchanger through a pipeline One outlet of the vacuum dryer is connected to the jet pump system. The secondary steam generated by the evaporation of the material in the vacuum dryer is injected by the jet liquid through the jet pump system. After being pressurized by the jet pump, the temperature rises, and then the steam The form overflows from the spray liquid and is separated from the spray liquid. The water vapor enters the heat exchanger to heat the heat medium water, and the heat medium condensed water is heated to form saturated water vapor and enters the vacuum dryer.

The jet pump system includes a jet pump, a pump and a heater, the vacuum dryer is connected to the jet pump, the jet pump is connected to the pump, the jet pump and the pump are connected to a heating device, and a heater is installed in the heating device.

The beneficial effects of the utility model:

The utility model uses a jet pump to recompress the secondary steam, improves the taste of waste heat, can effectively recover the latent heat of the secondary steam, has small heat loss and high thermal efficiency of the system.

The energy-saving vacuum drying process and system proposed by the utility model recycles the waste heat of drying. In the system, the heat is fully utilized in stages. The whole system has high thermal efficiency, sufficient heat utilization, and low energy consumption of the system.

Description of drawings

The overall structure schematic diagram of Fig. 1 the utility model;

In the figure, 1-vacuum dryer, 2-heat exchanger, 3-jet pump system, 4-jet pump, 5-pump, 6-heater.

detailed description:

Below in conjunction with accompanying drawing, the utility model is described in detail:

In FIG. 1 , an energy-saving vacuum drying system includes at least one vacuum dryer 1 , one heat exchanger 2 and one jet pump system 3 .

An energy-saving vacuum drying process, comprising:

A. The material enters the vacuum dryer through the feeding device. Inside the vacuum dryer, when the temperature of the material rises to about 70°C, it is dehydrated and dried under low pressure, and the moisture content of the dried material decreases.

B. After the steam enters the dryer to heat the material, the steam condenses into water, and the high-temperature condensed water enters the heat exchanger, where it exchanges heat with steam (water vapor overflowing from the jet pump system), and is heated to generate water vapor, water The steam enters the vacuum dryer and circulates to complete the drying of the material.

C. The secondary steam produced by the evaporation of material moisture in the vacuum dryer is injected by the injection liquid through the jet pump, and the temperature rises after being pressurized by the jet pump, and then overflows from the injection liquid in the form of saturated water vapor, and is separated from the injection liquid .

Inside the vacuum dryer 1, the pressure is maintained at -0.092—-0.098MPa. After the material enters the vacuum dryer 1 through the feeding device, the temperature of the material rises, and it is dehydrated and dried under low pressure.

The heating method of the vacuum dryer 1 is internal heating. After the steam enters the dryer 1 to heat the material, the steam condenses into water, and the high-temperature condensed water enters the heat exchanger 2. ) for heat exchange, is heated to generate saturated water vapor, and the water vapor enters the first cycle of the vacuum dryer to complete the drying of the material.

The secondary steam produced by the evaporation of material moisture in the vacuum dryer 1 is ejected by the high-temperature jet liquid through the jet pump 4, overflows the ejected liquid in the form of water vapor, and enters the heat exchanger 2 to exchange heat with the heat medium water.

The heat medium condensed water is heated to form saturated water vapor and enters the vacuum dryer 1 to complete the drying process of the material as a heat medium.

The core device of this process adopts vacuum dryer 1, and the heat medium is water vapor. Under the condition of vacuum and negative pressure, the boiling point of water decreases, and water evaporates at low temperature. Vacuum drying solves the problem that some materials are difficult to dehydrate, and at the same time avoids the problem of volatilization of heat-sensitive components of some materials at high temperatures. A heater 6 is installed in the jet pump system 3. When the system is turned on, industrial waste heat or electric heating can be used to heat the spray liquid. After the system runs normally, the heater 6 stops using. Jet pump system 3 The temperature of the injection liquid is higher than 100°C. After the secondary steam is injected by the jet pump, it mixes with the injection liquid. After being pressurized by the injection liquid to the back pressure at the outlet of the injection pipe, it overflows the system in the form of saturated water vapor and enters the exchange system. The heater 2 heats the heat medium water.

There are heat exchange tubes inside the vacuum dryer 1, and the vacuum dryer 1 is connected to the jet pump system 3. After the secondary steam generated by the vacuum dryer 1 is heated by the injection liquid, the steam exchanges heat with the heat medium, and the secondary steam is recovered. of heat.

The jet pump system 3 includes a jet pump 4, a pump 5, a heater 6, etc., and the jet liquid is a liquid with a high boiling point.

Although the specific implementation of the utility model has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the utility model. Those skilled in the art should understand that on the basis of the technical solution of the utility model, those skilled in the art do not need to Various modifications or deformations that can be made with creative efforts are still within the protection scope of the present utility model.

Claims (2)

1. An energy-saving vacuum drying system, characterized in that it includes a vacuum dryer, the inlet of the vacuum dryer is connected to the outlet of the heat exchanger through a pipeline, and an outlet of the vacuum dryer is connected to the inlet of the heat exchanger through a pipeline , the other outlet of the vacuum dryer is connected to the jet pump system. The secondary steam generated by the evaporation of material moisture in the vacuum dryer is ejected by the jet liquid through the jet pump system, and the temperature rises after being pressurized by the jet pump, and then saturated with water The form of steam overflows from the spray liquid and is separated from the spray liquid. The saturated water vapor enters the heat exchanger to heat the heat medium water, and the heat medium condensed water is heated to form saturated water vapor and enters the vacuum dryer. 2. A kind of energy-saving vacuum drying system as claimed in claim 1, characterized in that, the jet pump system comprises a jet pump, a pump and a heater, the vacuum dryer is connected with the jet pump, the jet pump is connected with the pump, and the jet pump is connected with the jet pump. Both the pump and the pump are connected with a heating device, and a heater is installed in the heating device.