WO2017190505A1

WO2017190505A1 - Heat pump-reinforced salt-concentration-differential power generation device using vapour differential pressure energy method under positive temperature difference

Info

Publication number: WO2017190505A1
Application number: PCT/CN2016/109365
Authority: WO
Inventors: 王焕光; 闫文杰; 辛毅; 吴迪
Original assignee: 中国矿业大学
Priority date: 2016-05-06
Filing date: 2016-12-12
Publication date: 2017-11-09
Also published as: AU2016405486B2; AU2016405486A1; AU2016405486B9; CA3000629A1; CN105736269B; CA3000629C; CN105736269A

Abstract

Disclosed is a heat pump-reinforced salt-concentration-differential power generation device using a vapour differential pressure energy method under a positive temperature difference. The power generation device comprises a heat pump heating and circulating device and a salt-concentration-differential power generation device using the vapour differential pressure energy method. The heat pump heating and circulating device comprises a condenser (7), a heat pump pipeline (9), a throttle valve (10), an evaporator (12) and a compressor (22). The salt-concentration-differential power generation device using the vapour differential pressure energy method comprises a low-pressure container (11), a high-pressure container (8), an expander (23), a differential pressure gauge (24) and an expander pipeline (11). By the heat pump heating and circulating, heat is absorbed from a concentrated solution so as to lower the temperature of the concentrated solution, the heat is released to a dilute solution so as to increase the temperature of the dilute solution, so that the inverse temperature difference generated by heat absorption through evaporation of water from the dilute solution and heat release through condensation of vapour in the concentrated solution is effectively offset. The positive temperature difference is maintained and enlarged, a positive saturated vapour differential pressure is in turn maintained and enlarged, thereby facilitating the expander (23) to do work. The energy utilization efficiency is high, the loss is small, the cost is cheap, the applicability is good, and the machining is simple and convenient.

Description

Steam pressure difference energy salt differential power generation device under positive temperature difference enhanced by heat pump

Technical field

The invention relates to the field of salt difference power generation, and particularly relates to a steam pressure difference energy salt difference power generation device under positive temperature difference of heat pump strengthening.

Background technique

With the advancement of society and the rapid development of the world economy, people's demand for energy is increasing day by day. As far as the current development of the world's energy is concerned, fossil energy will still occupy a major position for a long time in the future, but fossil energy as a A non-renewable energy source also faces a series of problems such as depletion and environmental pollution. This urgently requires us to find new energy sources to replace fossil energy. The ocean is an inexhaustible treasure house, which contains abundant marine energy resources. The ocean energy resources usually refer to the renewable natural energy contained in the ocean, and the salt water difference is the most important one. . The salt difference energy is the chemical potential difference energy between seawater and fresh water or between two seawaters with different salt concentrations. It mainly exists at the junction of rivers and seas, and has the characteristics of clean, renewable and huge reserves. In addition, salt lakes and underground salt mines in freshwater-rich areas can also use salt energy. Salt difference energy is the most energy-renewable energy source in ocean energy. Usually, the chemical potential difference between seawater (3.5% salinity) and river water is equivalent to the water level drop of 240m. Moreover, the salt in the ocean is rich in energy resources. It is estimated that there is a salt energy difference of 2.6 TW available on the earth, and its energy is even larger than the temperature difference. In China, according to statistics, the annual runoff of coastal rivers is about 1.7×10 ¹² -1.8×10 ¹² m ³ , and the annual runoff of the main rivers is about 1.5×10 ¹² -1.6×10 ¹² m ³ . The coastal salt energy resource reserves are about 3.9×10 ¹⁸ J, and the theoretical power is about 1.25×10 ¹¹ W. Among them, the resources along the Yangtze River estuary and the south of the Dajiang River estuary account for 92.5% of the national total, and the theoretical power is estimated to be 0.86 × 10 ¹¹ KW. In particular, the flow rate of the Yangtze River estuary is 2.2 × 10 ⁴ m ³ /s, which can generate 5.2 × 10 ¹⁰ W. In addition, many inland salt lakes are available in Qinghai Province and other places in China.

At present, the forms of salt difference power generation mainly include: pressure delay infiltration method, reverse electrodialysis method, vapor pressure difference method, electrochemical capacitance method and the like. Among them, the most studied are the pressure delay infiltration method and the reverse electrodialysis method, and the principle of the vapor pressure difference energy method is to drive the turbine to generate electricity by using the vapor pressure difference between different concentration salt solutions. The biggest advantage of this method is that it avoids the dependence on the permeable membrane, but because of the low temperature, the evaporation is small, the pressure difference is too small, and the vapor pressure difference between seawater and fresh water with a concentration of 3.45% at normal temperature is only 10-20mmHg. Therefore, the turbine diameter needs to be made very large to ensure sufficient power generation, and the upper surface of the dilute solution is due to moisture. Evaporation will gradually lower the temperature on the side, and when the moisture reaches the upper surface of the concentrated solution, the temperature rises due to condensation and exothermic heat, and a reverse temperature difference is gradually formed, which hinders the forward pressure difference, and if the concentrated solution is condensed by water vapor, When the temperature rise of 0.5 °C, the pressure difference will be offset, so the steam pressure difference method salt difference power generation is difficult to use.

Summary of the invention

Technical Problem: The object of the present invention is to solve the deficiencies in the prior art, and to provide a method of eliminating a reverse temperature difference, increasing a positive temperature difference, increasing a pressure difference, increasing an expander's work, high energy utilization efficiency, and low loss. The low-cost, simple and convenient heat pump-enhanced positive temperature difference steam differential pressure energy salt differential power generation device.

Technical Solution: The steam differential pressure energy salt difference power generation device under the positive temperature difference of the heat pump of the present invention comprises a heat pump heating cycle device and a vapor pressure difference energy salt difference power generation device;

The heat pump heating circulation device includes a condenser, a heat pump pipe, a throttle valve, an evaporator, a compressor, and the condenser, the throttle valve, the evaporator, and the compressor are sequentially connected through the heat pump pipe and form a circulation device;

The vapor pressure difference energy salt difference power generation device comprises a low pressure vessel, a high pressure vessel, an expander, a differential pressure gauge, an expander pipeline; the low pressure vessel and the high pressure vessel are connected through the expander pipeline, the expander Provided in the expander duct, the differential pressure gauge is disposed between the expander outlet and the inlet;

The evaporator is disposed in the low pressure vessel, the low pressure vessel is filled with a concentrated solution; the condenser is disposed in the high pressure vessel, and the high pressure vessel is filled with a dilute solution;

The concentrated solution is a saturated lithium bromide or a saturated sodium chloride solution; the diluted solution is a solution having a concentration of less than 10%.

Preferably, the vapor pressure difference energy salt difference power generation device further comprises a dilute solution container, a dilute solution replenishing solution, a dilute solution pump, a dilute solution pump pipe, a concentrated solution container, a concentrated solution replenishing solution, a concentrated solution pump, a concentrated solution pump. pipeline;

Disposing the dilute solution replenishing liquid in the dilute solution container, the dilute solution container is connected to the high-pressure container through the dilute solution pump pipeline, and the dilute solution pump is disposed on the dilute solution pump pipeline;

The concentrated solution replenishing liquid is placed in the concentrated solution container, and the concentrated solution container is connected to the low pressure container through the concentrated solution pump pipe, and the concentrated solution pump is disposed on the concentrated solution pump pipe.

Preferably, the vapor differential energy salt differential power generating device further comprises a vacuum pump connected to the low pressure vessel through a vacuum pump pipe.

Preferably, the bottom of the low-pressure vessel is provided with a drain pipe, and the drain pipe is provided with a valve.

Preferably, the heat pump pipe connected to the evaporator and the evaporator is provided with a throttle valve.

Advantageous Effects: The heat pump enhanced positive pressure difference of the present invention is a vapor pressure difference energy salt difference power generation device, which is heated by a heat pump to absorb heat in a concentrated solution to lower the temperature of the concentrated solution, and the exothermic heat in the dilute solution causes the temperature of the diluted solution to rise. High, effectively offsets the evaporation of heat in the dilute solution, the inverse temperature difference caused by the condensation of water vapor in the concentrated solution, maintains and expands the positive temperature difference, thereby maintaining and expanding the positive saturated vapor pressure difference, and doing work on the expander It has a promoting effect; high energy utilization efficiency, low loss, low cost, good applicability, and simple and convenient processing.

DRAWINGS

Figure 1 is a schematic view of the structure of the present invention.

detailed description

The present invention will be further described below in conjunction with the embodiments in the drawings:

As shown in FIG. 1 , the heat pump enhanced positive temperature difference steam differential pressure energy salt difference power generation device of the present invention comprises a heat pump heating cycle device and a vapor pressure difference energy salt difference power generation device; mainly composed of an expander pipe 1. Dilute solution pump pipe 2, dilute solution pump 3, dilute solution container 4, dilute solution replenishing liquid 5, dilute solution 6, condenser 7, high pressure container 8, heat pump pipe 9, throttle valve 10, low pressure container 11, evaporator 12 , valve 13, drain pipe 14, concentrated solution 15, concentrated solution container 16, concentrated solution replenishing liquid 17, concentrated solution pump pipe 18, concentrated solution pump 19, vacuum pump 20, vacuum pump pipe 21, compressor 22, expander 23, The differential pressure gauge 24 is composed.

Wherein, the heat pump heating circulation device comprises a condenser 7, a heat pump pipe 9, a throttle valve 10, an evaporator 12, a compressor 22, a condenser 7, a throttle valve 10, an evaporator 12, and a compressor 22 which are sequentially connected through a heat pump pipe 9. And form a circulation device. The vapor pressure difference energy salt difference power generation device comprises a low pressure vessel 11, a high pressure vessel 8, an expander 23, a differential pressure gauge 24, an expander pipe 1; the low pressure vessel 11 and the high pressure vessel 8 are connected through an expander pipe 1, and the expander 23 is arranged In the expander pipe 1, a differential pressure gauge 24 is disposed on the expander pipe 1, and a differential pressure gauge 24 is disposed between the outlet of the expander 23 and the inlet. The evaporator 12 is disposed in the low pressure vessel 11, and the low pressure vessel 11 is provided with a concentrated solution 15; the condenser 7 is disposed in the high pressure vessel 8, and the high pressure vessel 8 is installed therein. There is a dilute solution 6. The concentrated solution 15 is a saturated lithium bromide or a saturated sodium chloride solution; the diluted solution 6 is a solution having a concentration lower than 10%.

The condenser 7 is placed in the dilute solution 6 to heat the dilute solution 6, and the evaporator 12 is placed in the concentrated solution 15 to cool the concentrated solution 15. The compressor 22 is driven by an external motor, and the heat pump pipe sequentially turns the compressor 22, the condenser 7, and the throttling. Valve 10 and evaporator 12 are connected to form a heat pump heating cycle.

The steam pressure difference energy salt difference power generation device further comprises a dilute solution container 4, a dilute solution replenishing liquid 5, a dilute solution pump 3, a dilute solution pump pipe 2, a concentrated solution container 16, a concentrated solution replenishing liquid 17, a concentrated solution pump 19, and a rich Solution pump line 18. A dilute solution replenishing liquid 5 is disposed in the dilute solution container 4, and the dilute solution container 4 is connected to the high pressure container 8 through the dilute solution pump line 2, and the dilute solution pump 3 is disposed on the dilute solution pump line 2. The concentrated solution container 16 is provided with a concentrated solution replenishing liquid 17, and the concentrated solution container 16 is connected to the low pressure container 11 through the concentrated solution pump line 18, and the concentrated solution pump line 18 is provided with a concentrated solution pump 19.

The vapor pressure difference method salt difference power generation device further includes a vacuum pump 20 that is connected to the low pressure vessel 11 through a vacuum pump line 21. The bottom of the low pressure vessel 11 is provided with a drain conduit 14 on which a valve 13 is provided. A throttle valve 10 is disposed on the heat pump conduit 9 to which the condenser 7 is connected to the evaporator 12.

In the vapor pressure difference energy salt difference power generation circuit, the high pressure container 8 contains a dilute solution 6, the dilute solution container 4 is filled with a dilute solution replenishing liquid 5, and the dilute solution pump 3 is a dilute solution replenishing liquid in the dilute solution container 4. 5 is added to the high pressure container 8, the concentrated solution 15 is contained in the low pressure container 11, the concentrated solution replenishing liquid 17 is contained in the concentrated solution container 16, and the concentrated solution replenishing liquid 17 in the concentrated solution container 16 is added to the concentrated solution container 17 In the low-pressure vessel 11, at the same time, the low-pressure vessel 11 is connected to the vacuum pump 20 through the vacuum pump pipe 21 to maintain the internal vacuum condition, and the bottom of the low-pressure vessel 11 is connected to the drain pipe 14 through the valve 13, and the high-pressure vessel 8 and the low-pressure vessel 11 are expanded. The machine pipe 1 is connected to the expander 23, the expander 23 is located between the low pressure vessel 11 and the high pressure vessel 8, and the differential pressure gauge 24 is located on both sides of the expander 23, thereby constituting the entire vapor pressure difference energy salt difference power generation circuit.

Under the same temperature conditions, the dilute solution 6 contained in the high pressure vessel 8 is more easily evaporated than the concentrated solution 15 contained in the low pressure vessel 11, and the vacuum pump 20 creates a vacuum condition for the low pressure vessel 11, so that the pressure in the high pressure vessel 8 is high. In the pressure in the low-pressure vessel 11, the water vapor in the high-pressure vessel 8 is driven by the expander pipe 1 to generate electricity due to the pressure difference, and the water vapor then enters the low-pressure vessel 11 and the concentrated solution in the low-pressure vessel 11 The surface condensation is exothermic. During the continuous operation of the device, the dilute solution 6 in the high pressure vessel 8 is reduced by the evaporation of water, and the dilute solution pump 3 replenishes the dilute solution through the dilute solution pump pipe 2. The liquid 5 is replenished into the high pressure container 8 to maintain the liquid level of the dilute solution 6 in the high pressure container 8, and the surface of the concentrated solution 15 in the low pressure container 11 is also condensed by the water vapor, so that the concentrated solution 15 is diluted and the concentration is lowered. The pipe 14 timely discharges the diluted concentrated solution 15 into the low-pressure vessel 11 , and the concentrated solution pump 19 quantitatively replenishes the concentrated solution replenishing liquid 17 into the low-pressure vessel 11 through the concentrated solution pump pipe 18 to maintain the concentration of the concentrated solution 15 in the low-pressure vessel 11 change. At the same time, due to the evaporation of water in the dilute solution 6, the temperature in the high pressure vessel 8 is gradually lowered, and the water vapor in the concentrated solution 15 is condensed and released, so that the temperature in the low pressure vessel 11 is gradually increased, thereby generating a low temperature of the high pressure vessel 8. At the temperature of the low pressure vessel 11, the reverse temperature difference of the high pressure vessel 8 weakens the effect of the forward pressure difference to reduce the work of the expander 23, and the evaporator 12 is disposed in the concentrated solution 15 of the low pressure vessel 11, and the dilute solution in the high pressure vessel 8 The condenser 7 is disposed in the sixth stage, and is connected to the compressor 22 and the throttle valve 10 through the heat pump pipe 9, and constitutes a heat pump heating cycle. The medium in the heat pump heating cycle absorbs heat in the evaporator 12 to evaporate, so that the temperature of the concentrated solution 15 is lowered. The condensation of water vapor on the surface of the concentrated solution 15 is promoted, so that the pressure in the low pressure vessel 11 is further lowered, and the working medium in the heat pump heating cycle is cooled and released in the condenser 7, so that the temperature of the diluted solution 6 is raised, and the water is promoted. The evaporation of the surface of the solution 6 causes the pressure in the high pressure vessel 8 to further increase, not only counteracting the inverse temperature difference caused by the condensation of the water vapor in the concentrated solution 15 due to the evaporation of the water in the dilute solution 6, and To produce a positive temperature differential, further expansion pressure, acting to promote the expander 23, the vapor pressure difference can strengthen the difference of salt generation, increase system power.

The heat pump enhanced positive temperature difference steam differential pressure energy salt difference power generation device of the present invention is heated by a heat pump to absorb heat in a concentrated solution to lower the temperature of the concentrated solution, and the exothermic heat in the dilute solution causes the temperature of the diluted solution to rise, effectively It counteracts the inverse temperature difference caused by the evaporation of water in the dilute solution and the condensation and exotherm of water vapor in the concentrated solution, maintaining and expanding the positive temperature difference, thereby maintaining and expanding the positive saturated vapor pressure difference, which promotes the work of the expander. High energy utilization efficiency, low loss, low cost, good applicability, and simple and convenient processing.

Claims

A heat pump enhanced positive pressure difference steam differential pressure energy salt difference power generation device, characterized in that: a heat pump heating cycle device and a steam pressure difference energy salt difference power generation device;

The heat pump heating cycle device comprises a condenser (7), a heat pump pipe (9), an evaporator (12), a compressor (22), the condenser (7), an evaporator (12), a compressor (22) Connecting the heat pump conduits (9) in sequence and forming a circulation device;

The vapor pressure difference energy salt difference power generation device comprises a low pressure vessel (11), a high pressure vessel (8), an expander (23), a differential pressure gauge (24), an expander pipeline (1); and the low pressure vessel (11) And the high pressure vessel (8) is connected through the expander pipe (1), the expander (23) is disposed in the expander pipe (1), and the differential pressure gauge (24) is disposed at the Between the outlet of the expander (23) and the inlet;

The evaporator (12) is disposed in the low pressure vessel (11), the low pressure vessel (11) is provided with a concentrated solution (15); the condenser (7) is disposed in the high pressure vessel (8) The high pressure vessel (8) is filled with a dilute solution (6);

The concentrated solution (15) is a saturated lithium bromide or a saturated sodium chloride solution; the diluted solution (6) is a solution having a concentration of less than 10%.
The heat pump-enhanced positive pressure difference steam differential pressure energy salt differential power generation device according to claim 1, wherein the vapor pressure difference energy salt difference power generation device further comprises a dilute solution container (4) and a thinner Solution replenishing solution (5), dilute solution pump (3), dilute solution pump tubing (2), concentrated solution container (16), concentrated solution replenishing solution (17), concentrated solution pump (19), concentrated solution pump tubing (18 );

The dilute solution replenishing liquid (5) is placed in the dilute solution container (4), and the dilute solution container (4) is connected to the high pressure container (8) through the dilute solution pump pipe (2), Disposed the dilute solution pump (3) on the dilute solution pump pipe (2);

The concentrated solution replenishing liquid (17) is placed in the concentrated solution container (16), and the concentrated solution container (16) is connected to the low pressure container (11) through the concentrated solution pumping pipe (18), The concentrated solution pump (19) is disposed on the concentrated solution pump line (18).
The heat pump enhanced positive differential temperature steam differential pressure energy salt differential power generation device according to claim 1, wherein the vapor differential energy salt differential power generation device further comprises a vacuum pump (20), the vacuum pump (20) is connected to the low pressure vessel (11) through a vacuum pump line (21).
A heat pump enhanced positive temperature difference steam differential pressure method salt difference power generation according to claim The device is characterized in that: the bottom of the low-pressure vessel (11) is provided with a drain conduit (14), and the drain conduit (14) is provided with a valve (13).
The heat pump enhanced positive differential temperature steam differential pressure energy salt differential power generation device according to claim 1, characterized in that: the condenser (7) is connected to the evaporator (12) of the heat pump pipe (9) A throttle valve (10) is provided.