CN209704638U - A serial single-screw expansion unit and power generation device - Google Patents

Abstract

The utility model relates to a kind of tandem single-screw expander group and power generator, including the first single-screw expander (1), second single-screw expander (2), first shaft coupling (3), second shaft coupling (4) and pipeline (6), first single-screw expander (1) and the second single-screw expander (2) pass through first shaft coupling (3) differential concatenation, second single-screw expander (2) is connect by second shaft coupling (4) with generator (5), pipeline (6) is connected to the first single-screw expander (1) and the second single-screw expander (2).Single-screw expander quantity is generally only one in the prior art, the deficiency that there are energy conversion efficiencies is low, system is unstable and working speed is excessively high, this expansion unit is using the segmentation expansion of multimachine differential concatenation, the enthalpy drop ratio that single expanding machine can be reduced improves the energy conversion efficiency and stability and economy of system.

Description

A serial single-screw expansion unit and power generation device

technical field

The utility model relates to the technical field of single-screw expanders, in particular to a series-type single-screw expander unit and a power generation device.

Background technique

my country's industrial waste heat and pressure resources are abundant, and large-scale heavy chemical industrial production enterprises have realized the utilization. However, due to the limitation of expander technology, the widely distributed small-scale waste heat and pressure resources have not been effectively utilized.

As a new type of device that converts thermal energy into mechanical energy, the single-screw expander is mainly composed of a star wheel, a screw, a screw shaft and a casing. Compared with the traditional steam turbine, the single-screw expander has simple structure, good economy, high reliability, convenient installation and maintenance, good force balance, high pressure resistance, and easy miniaturization design. It is a decentralized small-scale waste heat and pressure resource recovery. ideal device. However, in the existing technical scheme of using single-screw expanders for recovery of waste heat and pressure resources, the number of single-screw expanders is generally one. In the prior art, the expansion ratio of a single machine is too large, the efficiency is low, and the working speed is too high. Problems affect the high efficiency, stability and economy of waste heat and pressure resource recovery. Therefore, it is necessary to make improvements based on the technical problems of applying single-screw expanders in the prior art to improve the utilization efficiency of waste heat and pressure resources while taking into account the stability and economy of the expander system.

Utility model content

The technical problem to be solved by the utility model is to provide a single-screw expansion unit with higher energy conversion efficiency, better stability and better economy.

In order to solve the above problems, the utility model provides a tandem single-screw expansion unit, including a first single-screw expander 1, a second single-screw expander 2, a first coupling 3, a second coupling 4, a pipeline 6. The first single-screw expander 1 and the second single-screw expander 2 are reversely connected in series through the first coupling 3, the second single-screw expander 2 is connected to the generator 5 through the second coupling 4, and the pipeline 6 The first single-screw expander 1 and the second single-screw expander 2 are connected.

The first single-screw expander 1 includes a first casing 11, a first star wheel 12, a first screw 13 and a first screw shaft 14, wherein the first star wheel 12 is distributed on both sides of the first screw 13, and the first The screw 13 and the first star wheel 12 mesh with each other and are installed in the first casing 11; the second single-screw expander 2 includes a second casing 21, a second star wheel 22, a second screw 23, and a second screw shaft 24 , wherein the second star wheel 22 is distributed on both sides of the second screw 23 , and the second screw 23 and the second star wheel 22 engage with each other and are installed in the second housing 22 .

One side of the first casing 11 is opened with a first single-screw expander air inlet 111 , and the other side of the first casing 11 is opened with a first single-screw expander air outlet 112 . One side of the second casing 21 is opened with a second single-screw expander air inlet 211 , and the other side of the second casing 21 is opened with a second single-screw expander air outlet 212 . The pipeline 6 is airtightly connected with the gas outlet 112 of the first single-screw expander and the gas inlet 211 of the second single-screw expander respectively.

The two ends of the first screw shaft 14 are respectively the first screw shaft input end 141 and the first screw shaft output end 142, and the two ends of the second screw shaft 24 are respectively the second screw shaft input end 241 and the second screw shaft output end 242. The output end 142 of the first screw shaft is connected with the input end 241 of the second screw shaft through the first coupling 3 .

Since the new technical solution adopted by the utility model is to connect multiple single-screw expanders in series, the waste heat and pressure gas can be expanded in stages, the expansion ratio of each single machine can be reduced, and each single machine can be closer to the ideal enthalpy. Working in the state of reduced ratio improves the efficiency of converting heat energy into mechanical energy. The lower expansion ratio of a single machine can also greatly reduce the gas flow rate, improve the flow characteristics, and reduce the flow loss of gas. Since the single-screw expander is a volumetric expander, the volumetric flow rate is proportional to the rotational speed. After multi-machine serial expansion is adopted, the expansion ratio of the single machine is reduced, and the volumetric flow rate in the casing is reduced accordingly. Therefore, each single-screw expander casing The rotation speed of the internal screw and star wheel rotating pair is reduced, which is beneficial to improve the service life of bearings and seals, and enhance the stability of the system; in addition, when converting waste heat and pressure gas with the same amount of energy, a series single-screw expansion unit is used Compared with the scheme using only one single-screw expander, the rotation speed of the output end of the screw shaft connected to the input end of the generator can be greatly reduced, and it can be directly connected to the generator through a coupling without a reduction mechanism. The economy is better.

As a preferred technical solution, the first coupling, the second coupling and the couplings connecting other single-screw expanders in series are all quincunx type elastic couplings. The plum blossom type elastic coupling has a certain degree of elasticity and has the function of buffering and compensating displacement. As a connecting piece, it can reduce the installation requirements of the serial single-screw expansion unit and facilitate the maintenance and maintenance of the equipment.

As a preferred technical solution, the connecting pipe is an insulated connecting pipe. The use of thermal insulation connecting pipes can reduce the heat loss of waste heat and pressure gas in the pipeline circulation process.

The content of the utility model also includes an industrial waste heat and pressure power generation device including the above-mentioned single-screw expansion unit. my country's industry is rich in waste heat and pressure resources, which have been utilized in large-scale heavy chemical industrial production enterprises. However, due to the limitation of expander technology, the widely distributed small-scale waste heat and pressure resources have not been effectively utilized. The tandem single-screw expansion unit and power generation device provided by the utility model can be used for the effective utilization of distributed small-scale waste heat and pressure resources, and supplements the deficiencies of expander technology in the field of distributed small-scale waste heat and pressure resource utilization.

Description of drawings

Fig. 1 is a structural schematic diagram of a serial single-screw expander;

Fig. 2 is a schematic diagram of the pipe connection relationship of a serial single-screw expander.

The reference signs and components involved in the accompanying drawings are as follows:

The first single-screw expander 1, the second single-screw expander 2, the first coupling 3, the second coupling 4, the generator 5, the pipeline 6, the first casing 11, the first star wheel 12, the second A screw 13, the first screw shaft 14, the first screw shaft input end 141, the first screw shaft output end 142, the second casing 21, the second star wheel 22, the second screw rod 23, the second screw shaft 24, the second screw shaft The input end 241 of the second screw shaft, the output end 242 of the second screw shaft, the air inlet 111 of the first single-screw expander, the air outlet 112 of the first single-screw expander, the air inlet 211 of the second single-screw expander, the second single-screw expander Air outlet 212 of the screw expander.

Detailed ways

Fig. 1, Fig. 2 have shown the first kind of embodiment of the present utility model.

Example 1

As shown in FIG. 1 , a serial single-screw expansion unit includes a first single-screw expander 1 , a second single-screw expander 2 , a first coupling 3 , a second coupling 4 , and a pipeline 6 . The first single-screw expander 1 and the second single-screw expander 2 are connected in reverse series through a first coupling 3, and the second single-screw expander 2 is connected to a generator 5 through a second coupling 4. The first single-screw expander 1 includes a first casing 11, a first star wheel 12, a first screw 13 and a first screw shaft 14, wherein the first star wheel 12 is distributed on both sides of the first screw 13, and the first The screw rod 13 is engaged with the first star wheel 12 and installed in the first housing 11 . The second single-screw expander 2 includes a second casing 21, a second star wheel 22, a second screw 23, and a second screw shaft 24, wherein the second star wheel 22 is distributed on both sides of the second screw 23, and the second The second screw 23 and the second star wheel 22 are engaged with each other and installed in the second casing 22 . One side of the first casing 11 is opened with a first single-screw expander air inlet 111 , and the other side of the first casing 11 is opened with a first single-screw expander air outlet 112 . One side of the second casing 21 is opened with a second single-screw expander air inlet 211 , and the other side of the second casing 21 is opened with a second single-screw expander air outlet 212 . The two ends of the first screw shaft 14 are the first screw shaft input end 141 and the first screw shaft output end 142 respectively, and the two ends of the second screw shaft 24 are the second screw shaft input end 241 and the second screw shaft output end 242 respectively. The output end 142 of the first screw shaft is connected to the input end 241 of the second screw shaft through the first coupling 3 .

As shown in FIG. 2 , the pipeline 6 communicates with the first single-screw expander 1 and the second single-screw expander 2 . The specific connection method is that the pipeline 6 is airtightly connected with the gas outlet 112 of the first single-screw expander and the gas inlet 211 of the second single-screw expander respectively.

The tandem single-screw expansion unit is applied to power generation with industrial waste heat and pressure.

When the tandem single-screw expander is in normal operation, the high-temperature and high-pressure waste heat gas enters the first casing 11 through the air inlet 111 of the first single-screw expander to expand, drives the screw to rotate to do work, and then is exhausted by the first single-screw expander. The air port 112 enters the second casing 21 through the heat preservation connecting pipe 6 through the air inlet 211 of the second single-screw expander to expand and perform work, converting heat energy into mechanical energy of the second screw shaft 24, and the output end 242 of the second screw shaft then The mechanical energy is transmitted to the generator, which converts the mechanical energy into electrical energy, and the residual gas is discharged out of the system through the exhaust port 212 of the second single-screw expander, completing the conversion and utilization of waste heat and pressure resources.

Since the new technical solution adopted in this embodiment 1 is to connect the first single-screw expander 1 and the second single-screw expander 2 in series, the waste heat and pressure gas can be expanded in stages, reducing the expansion of the first single-screw expander. The expansion ratio of the machine 1 and the second single-screw expander 2 can work in a state closer to the ideal enthalpy-drop ratio, which improves the efficiency of converting heat energy into mechanical energy. The lower expansion ratio of a single machine can also greatly reduce the gas flow rate, thus improving the flow characteristics and reducing the flow loss of gas. Since the single-screw expander is a volumetric expander, the volume flow rate is proportional to the rotation speed. After multi-machine series expansion is adopted, the expansion ratio of the single machine decreases, and the volume flow rate in the casing decreases accordingly. Therefore, the first casing 11 The speed reduction of the second star wheel 22, the second screw rod 23, and the second screw shaft 24 in the first star wheel 12, the first screw rod 13, the first screw shaft 14 and the second casing 21 is conducive to improving the bearing and seal. The service life of the system is enhanced; in addition, when converting waste heat and pressure gas with the same amount of energy, compared with the scheme of using a single-screw expander in series, the second screw shaft The rotational speed of the output end 242 can be greatly reduced, and it can be directly connected to the generator 5 through the second coupling 4 without the need of a speed reduction mechanism, so the economy is better.

Example 2

An industrial waste heat and pressure power generation device, comprising the single-screw expansion unit described in Embodiment 1.

The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings, but the present utility model is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those of ordinary skill in the art. For example, in the above embodiment, only the first single-screw expander and the second single-screw expander are connected in series. Obviously, the technical solution of a serial single-screw expander described in the utility model can also be applied In the case of more than 3 single-screw expanders connected in series.

Claims (9)

1. A single-screw expansion unit, comprising a first single-screw expander (1), a second single-screw expander (2), a first coupling (3), a second coupling (4), a generator (5), pipeline (6), is characterized in that, the first single-screw expander (1) and the second single-screw expander (2) are reversely connected in series through the first coupling (3), and the second single-screw expander The machine (2) is connected to the generator (5) through the second coupling (4), and the pipeline (6) communicates with the first single-screw expander (1) and the second single-screw expander (2). 2. The single-screw expansion unit according to claim 1, characterized in that, the first single-screw expander (1) comprises a first casing (11), a first star wheel (12), a first screw ( 13), and the first screw shaft (14), wherein the first star wheel (12) is distributed on both sides of the first screw (13), and the first screw (13) and the first star wheel (12) are engaged with each other and Installed in the first casing (11); the second single-screw expander (2) includes a second casing (21), a second star wheel (22), a second screw (23), and a second screw Shaft (24), wherein, the second star wheel (22) is distributed on both sides of the second screw (23), and the second screw (23) and the second star wheel (22) are engaged with each other and installed in the second casing ( 21) Inside. 3. The single-screw expander unit according to claim 2, characterized in that, a first single-screw expander air inlet (111) is opened on one side of the first casing (11), and the first machine The other side of the shell (11) has a first single-screw expander air outlet (112); one side of the second casing (21) has a second single-screw expander air inlet (211), so The other side of the second casing (21) is provided with a second single-screw expander gas outlet (212). 4. The single-screw expander unit according to claim 3, characterized in that, the pipeline (6) is connected to the air outlet (112) of the first single-screw expander and the air intake of the second single-screw expander respectively Port (211) airtight connection. 5. The single-screw expansion unit according to claim 2, characterized in that, the two ends of the first screw shaft (14) are respectively the first screw shaft input end (141) and the first screw shaft output end (142) , the two ends of the second screw shaft (24) are respectively the second screw shaft input end (241) and the second screw shaft output end (242). 6. The single-screw expansion unit according to claim 5, characterized in that, the output end (142) of the first screw shaft and the input end (241) of the second screw shaft pass through the first coupling ( 3) Docking. 7. The single-screw expansion unit according to claim 1, characterized in that, both the first coupling (3) and the second coupling (4) are plum-shaped elastic couplings. 8. The single-screw expansion unit according to claim 1, characterized in that the pipeline (6) is a thermal insulation connection pipeline. 9. An industrial waste heat and pressure power generation device, characterized in that it comprises the single-screw expansion unit according to any one of claims 1 to 8.