CN105174338B - Optically focused heats multiple-effect backheat matrix form air wetting dehumidification type solar energy sea water desalination apparatus - Google Patents

Abstract

The invention discloses a solar sea water desalination device of concentrating heating and multi-effect heating matrix type air humidification and dehumidification type, which comprises a light receiver, a transparent shell, a ventilating collector, an air channel and a dehumidifier. The transparent casing is located in the middle of the device, and the light reflected by the heliostat enters the humidification chamber through the transparent casing, irradiates the rod-shaped light receiver and the inner wall of the humidification chamber, and turns into heat to evaporate the seawater falling film. Seawater enters through the primary condenser, exchanges heat with the high-temperature and high-humidity air in the dehumidification chamber, and then enters the secondary condenser. Most of it is sprayed on the surface of the receiver through the primary humidification chamber to form a water film with a large specific surface area. A small amount of seawater is sent to the fourth-stage evaporation chamber for spraying to replenish circulating seawater. The seawater on the surface of the receiver evaporates after being heated by sunlight and exchanges heat and moisture with the air flowing from bottom to top. The saturated humid air is transported into the dehumidification chamber under the action of the fan, and the fed seawater is condensed to generate fresh water, which is finally ventilated and collected. collected by the server and delivered to the user.

Description

Concentrated heating, multi-effect heat recovery, matrix air humidification and dehumidification solar seawater desalination device

technical field

The invention relates to a device for directly using solar energy to humidify and dehumidify and extract fresh water, and belongs to the technical fields of solar heat utilization, seawater desalination and water treatment. Specifically, it relates to a tower-type concentrating multi-effect heat recovery matrix type humidification and dehumidification solar seawater desalination device.

Background technique

Using solar energy to desalinate seawater is energy-saving and environmentally friendly, so it is highly praised by people. The humidification and dehumidification type seawater desalination process separates the heating, evaporation and condensation processes, so that targeted technologies can be used to strengthen each process and improve the energy utilization efficiency of each process. At the same time, it also has the advantages of simple control, stable water production, and normal pressure. , low energy consumption, easy to combine with renewable energy and other advantages. Utilize high-efficiency solar concentrating systems, especially the existing tower-type concentrating systems, to generate high-intensity sunlight, which can be directly focused on seawater to generate high-temperature and high-pressure steam, which is input into traditional seawater desalination systems to generate fresh water. Corresponding improvements are made to the tower humidification and dehumidification evaporator to improve the performance of the solar seawater desalination device, which meets the development requirements of realizing the large-scale and low-cost application of the solar seawater desalination technology.

Application No. 201210181611.1 discloses a seawater evaporator for a concentrating seawater desalination device, which can be used for a tower-type solar seawater desalination device, but does not make full use of the latent heat of vaporization of high-temperature water vapor.

Application No. 201310411226.6 discloses a tandem multi-stage isothermal heating multi-effect reheating humidification dehumidification seawater desalination machine. Due to the existence of heat exchangers, there are many heat transfer links between the solar heat collection system and the seawater desalination system, thereby reducing the heat collection efficiency.

Contents of the invention

In view of this, in order to improve the performance of the existing solar seawater desalination device, increase its thermal energy utilization rate, and realize the high coupling of solar energy concentrating heat collection technology and new humidification and dehumidification traditional seawater desalination technology, the present invention provides a concentrating heating multi- Efficient heat recovery matrix air humidification and dehumidification solar seawater desalination device can make full use of the steam condensation latent heat in the dehumidification and humidification solar seawater desalination device, reduce the cost of fresh water per unit volume of solar seawater desalination, and improve the solar energy utilization rate in the seawater desalination device. It can be used in remote inland areas and islands where fresh water is scarce, especially in areas with high solar irradiance.

A concentrating heating multi-effect heat recovery matrix type solar seawater desalination device for air humidification and dehumidification, the seawater desalination device includes a ventilation collector, a light receiver, a transparent shell, an air duct, a circulating water pump, a humidification chamber, and a dehumidification chamber , a fan and a heating coil, wherein the inside of the humidification chamber includes a sea water heater, a light receiver and a network disk, and a dehumidifier inside the dehumidification chamber, and a ventilation liquid collector at the bottom.

Connection relationship: Multiple humidification chambers and dehumidification chambers are connected in series. The feed seawater first enters the first-stage dehumidification chamber, passes through the inner wall between the first stage and the second stage, and then enters the second-stage humidification and dehumidification chamber . The brine at the outlet of the second-stage dehumidifier is divided into two paths, one path returns to the first-stage humidification chamber, and the other path passes through the control valve and flowmeter to spray the fourth-stage light receiver together with the brine at the bottom of the fourth stage.

The brine at the bottom of the upper humidification chamber of the second stage enters the third-stage dehumidifier through the pipeline in series with the water pump, and finally returns to the second-stage humidification chamber for spraying. The brine at the bottom of the third-stage humidification chamber enters the fourth-stage dehumidifier through the pipeline in series with the water pump, and then returns to the third-stage humidification chamber for spraying.

The transparent casing is located outside the humidification chamber in the middle of the device and is a double-layer vacuum glass tube. The other parts are opaque shells. A hydrophilic film can be formed on the surface of the photoreceiver, which is uniformly distributed in the humidification chamber as a packed bed.

Beneficial effect:

(1) Heliostats are used to concentrate light without redundant pipelines. The sunlight directly irradiates the heating coil of the outer shell, or directly shines on the black light receiver through the middle transparent shell. The seawater directly absorbs sunlight, uses strong light to directly evaporate seawater, omits a heat exchanger, reduces heat transfer links, and improves heat collection efficiency.

(2) The black porous light receiver can increase the optical path of sunlight in the humidification chamber, so that the humidifier changes from passive absorption of light to active absorption of light, and strengthens the absorption efficiency of sprayed seawater on solar heat, so that the light receiving The falling film seawater on the device evaporates, which improves the reliability of the device.

(3) The heat exchange part on the concentrating tower, that is, all the devices in contact with seawater can be made of non-metallic materials. For example, the transparent shell that receives sunlight and evaporates seawater can be made of quartz glass, thereby improving the safety of the entire system. Corrosion resistance; reduces the cost of the device and is conducive to popularization and application.

(4) The use of multi-effect spraying system, hydrophilic black light receiver, and outer heating coil improves the heat and mass transfer between feed seawater and air, as well as the moisture content of humid air, increasing the distance between seawater and air The contact area uses the multi-effect reheating method to reduce the temperature difference between the feed seawater and the set start-up heating temperature, which shortens the start-up time of the device, reduces the discharge temperature of concentrated seawater, and effectively protects the ecological environment of the concentrated discharge sea area.

The invention improves the traditional dehumidification and humidification type solar seawater desalination system, and realizes multi-effect heat recovery through concentrated light heating. In terms of light concentration, sunlight is directly introduced into the humidifier, and seawater is directly evaporated at high temperature. In terms of heat utilization, the concentrated seawater at the bottom of the cavity is heated by the heating coil and dehumidifier and then sprayed to humidify the air, making full use of the latent heat of condensation of the humid air, and adopting a combination of multi-stage humidification and dehumidification to make full use of each effect. The heat energy obtained, the heat energy utilization of each effect in such a device is relatively balanced.

Description of drawings

Fig. 1 is the schematic diagram of four-stage matrix type seawater desalination machine of the present invention;

Fig. 2 is a structural diagram of a ventilation liquid collector of the present invention;

Fig. 3 is the internal distribution diagram of the two-stage structure adopting the columnar light receiver of the present invention;

Fig. 4 is the installation diagram of the two-stage seawater desalination machine of the present invention in the tower type solar seawater desalination device;

Fig. 5 is a schematic diagram of the four-stage coil matrix seawater desalination machine of the present invention.

Among them, 1—dehumidifier; 2—housing; 3—ventilation sink; 4—sprinkler; 5—incident light from the sun; 6—light receiver; 7—transparent shell; 8—flow meter; 9— Control valve; 10—insulation material; 11—fresh water outlet; 12—air duct; 13—fresh water channel; 14—feeding seawater; 15—concentrated brine; 16—circulating water pump; 17—humidification chamber; ; 19-fan; 20-grid; 21-support; 22-salt water channel; 23-heating coil; 24-heliostat; 25-steam; 26-fresh water tank;

detailed description

The present invention will be described in detail below with reference to the accompanying drawings and examples.

The invention provides a solar seawater desalination device of concentrated light heating multi-effect heat recovery matrix type air humidification and dehumidification type.

As shown in accompanying drawing 1, the present invention provides a solar desalination device of concentrating heating and multi-effect heat recovery matrix air humidification and dehumidification type. Road 12, humidification chamber 17, dehumidification chamber 18 and support 21. Feed seawater (14) enters from the right side of the bottom of the device, along the direction of water flow, from bottom to top, from right to left, and the humidification and dehumidification chambers in the device are named as the first stage, the second stage, the third stage and the first stage. level 4.

The overall connection relationship is as follows: multiple humidification chambers 17 and dehumidification chambers 18 are connected in series, the feed seawater first enters the first-stage dehumidification chambers 1-18, and passes through the inner wall between the first and second stages , and then enter the second stage humidification and dehumidification chamber. The brine at the outlet of the second-stage dehumidifier 2-1 is divided into two paths, one path returns to the first-stage humidification chamber 1-17, and the other path passes through the control valve 9 and flow meter 8 to the fourth stage together with the brine at the bottom of the fourth stage Level light receiver 4-6 spray.

The brine at the bottom of the upper humidification chamber 2-17 of the second stage enters the dehumidifier 3-1 of the third stage through the pipeline in series with the water pump 16, and finally returns to the humidification chamber 2-17 of the second stage for spraying. The brine at the bottom of the third-stage humidification chamber 3-17 enters the fourth-stage dehumidifier 4-1 through the pipeline in series with the water pump 16, and then returns to the third-stage humidification chamber 3-17 for spraying.

The thermal insulation material 10 is closely attached to the outer wall of the dehumidification chamber 18 of each stage device, so as to ensure that the heat will not be transferred into the dehumidification chamber, thereby affecting the effect of condensation in the chamber. The incident light is concentrated in the middle of the device, which imposes requirements on the tracking accuracy of the heliostat. The incident light passes through the transparent casing 7 and irradiates onto the black light receiver 6, directly heating the filmy seawater.

The black light receiver 6 will increase the optical path of sunlight in the evaporator, and most of the light will be reflected multiple times on the surface of the hole-shaped ceramic material, and can reach the inside of the black light receiver 6 array. Make the temperature of the black light receiver 6 close to the inside not too low.

The blower fan 19 is installed in the air duct and is positioned at one side of the dehumidification chamber 18, so that it is less affected by the heating of the surface layer and ensures that the blower fan works under permissible conditions.

As shown in accompanying drawing 2, the effect of described ventilated liquid collector 3 is, the seawater that sprays on the photoreceiver 6, carries out heat and moisture exchange with air to form wet saturated steam 25, under the drive of blower fan 19 in air channel 12 Enter the dehumidification chamber through the window of the ventilation collector 3, and the condensed fresh water 27 drops on the blades on the ventilation collector 3, and finally gathers in the fresh water tank 26 around the ventilation collector 3.

In one embodiment shown in Fig. 3, the view is a perspective perspective view of a two-stage structure, and the columnar light receivers 6 are reasonably distributed in the limited space of the humidifying chamber 17, so as to maximize the use of external incident light and increase the evaporation of sunlight at the same time. The optical path in the device enhances the absorption efficiency of seawater to solar heat. There is a heating coil 23 on the outer wall of the dehumidification chamber 18 to absorb light energy irradiated outside the dehumidification chamber 18 .

As shown in Figure 4, the evaporator that realizes concentrated direct heat, multi-effect heat recovery, and two-stage air humidification and dehumidification is applied in a tower-type solar seawater desalination device. The tower-type solar seawater desalination device includes a dehumidifier 1, a ventilation sink Device 3, light receiver 6, transparent casing 7, air duct 12, bracket 21, heating coil 23 and heliostat 24. The two-stage seawater desalination machine is installed and fixed on the bracket 21, and the heliostat 24 is located on one side of the device and faces the sun.

Specific connection method: Feed seawater is first pumped into the dehumidifier 1 in the first-stage dehumidification chamber 18 by the water pump 16 through the feed seawater pipeline, and then enters the dehumidifier 1 in the second-stage dehumidification chamber 18, and passes through the dehumidifier 1 After exchanging heat with the humid air outside, this part of seawater is divided into two paths and enters the second-stage and first-stage humidification chambers 17 respectively. Level 2 hydration. The concentrated seawater at the bottom of the second-stage humidification chamber 17 communicates with the seawater at the bottom of the first-stage humidification chamber 17 through the brine channel 22 at the bottom.

The seawater entering the first-stage humidification chamber 17 passes through the seawater sprayer 4 and sprays onto the multilayer hydrophilic light receiver 6 heated by sunlight. Driven by the fan 19, the air flows from bottom to top and exchanges heat and moisture with the seawater film to form hot and humid air that enters the first-stage dehumidification chamber 18, and the unevaporated concentrated seawater passes through the small holes on the sieve-shaped stainless steel grid plate 20 It flows to the bottom of the first stage humidification chamber 17, and is discharged out of the device through the bottom pipe.

In the second-stage humidification chamber 17, the concentrated seawater that has not been evaporated flows to the bottom of the chamber through the small holes on the sieve-shaped stainless steel mesh pan 20, and is pumped into the heating coil on the outer wall of the upper part of the device by the water pump 16 through the bottom pipe. 23 in. The seawater heated by sunlight in the heating coil 23 enters the second-stage seawater shower 4, sprays onto the multi-layered hydrophilic light receiver 6 heated by sunlight, and enters from the lower humidification chamber 17 to the upper part The hot and humid air in the dehumidification chamber 18 and the fresh water formed in the dehumidification chamber 18 are collected by the ventilation liquid collector 3 .

In an embodiment shown in FIG. 5 , the four-stage seawater desalination devices are arranged in a matrix, and the structures of each stage are consistent. The upper layer is a dehumidification chamber, and the lower layer is a humidification chamber. The incident light irradiates the whole device, and the outside of the dehumidification chamber inside the first and second units and the third and fourth units are all wrapped by the thermal insulation material 10 and the heating coil 23 .

The specific connection method is: the feed seawater is first pumped into the dehumidifier 1 in the first-stage dehumidification chamber by the circulating water pump 16 through the feed seawater pipeline, and then enters the dehumidifier 1 in the second-stage dehumidification chamber, and passes through the dehumidifier 1 outside After exchanging heat with the humid air, this part of seawater is divided into two paths, one path enters the seawater in the first-stage humidification chamber 17, passes through the seawater sprayer 4, and sprays the water on the surface of the black light receiver 6 directly heated by sunlight. On the membrane, the hydrophilic membrane and pores on the photoreceptor can form a large area of seawater evaporation layer. The other way passes through the control valve 9 and the flow meter 8, and enters the heating coil 23 outside the third and fourth dehumidification chambers 18 together with the seawater pipeline series circulating water pump 16 at the bottom of the fourth-stage humidification chamber 17. The heating coil 23 absorbs the incident heat of the sun, and reheats the seawater inside the coil. Finally, the high-temperature seawater is exported from the heating coil 23 and connected to the seawater shower 4 in the fourth-stage humidification chamber 17 .

The seawater pipeline at the bottom of the second-stage humidification chamber 17 is connected in series with the water pump 16 to the third-stage dehumidifier 1, and the heated seawater enters the heating coil 23 outside the first and second-stage dehumidification chambers 18. The heating coil 23 absorbs the heat of solar radiation to reheat the seawater. Finally, the high-temperature seawater is exported from the heating coil 23 and connected to the seawater sprayer 4 in the second-stage humidification chamber 17 .

The seawater pipeline at the bottom of the third-stage humidification chamber 17 is connected in series with the water pump 16 to the fourth-stage dehumidifier, and the heated seawater enters the seawater sprayer 4 in the third-stage humidification chamber for spraying.

Driven by the fan 19, the air flows from bottom to top and exchanges heat and moisture with the seawater film on the surface of the optical receiver 6 to form hot and humid air that enters the first-stage dehumidification chamber 18, and the unevaporated concentrated seawater passes through the sieve-type stainless steel network disk The hole on the 20 flows to the bottom of the first stage humidification chamber 17, and is discharged outside the device through the bottom pipe. Spray onto the multi-layer photoreceiver 6 heated by sunlight, the hot humid air entering the upper dehumidification chamber 18 from the lower humidification chamber 17 , and the fresh water formed in the dehumidification chamber 18 are collected by the ventilation collector 3 . The internal operation of other levels is basically the same.

The concentrated seawater at the bottom of the second-stage humidification chamber 17 communicates with the seawater at the bottom of the first-stage humidification chamber 17 through the brine channel at the bottom. The bottoms of the 3rd and 4th levels are also connected.

To sum up, the above are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (3)

1. optically focused heats multiple-effect backheat matrix form air wetting dehumidification type solar energy sea water desalination apparatus, it is characterised in that described Device include dehumidifier (1), ventilation converge liquid device (3), optical receiver (6), transparent shell (7), air channel (12), humidifier chamber (17), Dehumidify chamber (18), support (21) and heliostat (23)；Feed seawater (14) on the right side of bottom of device to enter, along seawater process side To from the bottom up, being turned left from the right side, humidification dehumidifying chamber is named as the 1st grade, the 2nd grade, 3rd level and the 4th grade successively in device；Every grade Point above and below two layers of cavity, in order that transparent shell (7) be located at device in the middle part of, humidifier chamber (17) and dehumidify chamber (18) as requested on Lower distribution；In structure of the upper strata for dehumidifying chamber (18), air channel (12) are arranged on wall in the inner part, and enterprising air port is located at dehumidifying Top of chamber, lower air outlet abuts against Dropbox (20) below；Upper strata is in the structure of humidifier chamber (17), enterprising air port is located at humidifier chamber (17) top, lower air outlet abuts against dehumidifier (1) below；Blower fan (19), which is arranged in air channel (12), is located at dehumidifying chamber (18) Side；Its integrated connection relation is：Multiple humidifier chambers (17) and dehumidifying chamber (18) are connected by series system, and charging seawater is first Into the 1st grade of dehumidifying chamber (1-18), the internal face through the 1st grade and the 2nd grade enters back into the 2nd grade of humidification dehumidifying chamber；2nd Level dehumidifier (2-1) outlet salt solution is divided into two-way, returns to all the way in the 1st grade of humidifier chamber (1-17), separately leads up to control valve (9) Sprayed with flowmeter (8) together with the salt solution of the 4th grade of bottom to the 4th grade of optical receiver (4-6)；2nd grade of top humidifier chamber (2- 17) salt solution of bottom, is entered in 3rd level dehumidifier (3-1) by pipeline relay pump (16), is eventually returned to the 2nd grade of humidifier chamber Sprayed in (2-17)；The salt solution of 3rd level humidifier chamber (3-17) bottom, is removed by pipeline relay pump (16) into the 4th grade In wet device (4-1), return and sprayed in 3rd level humidifier chamber (3-17).

2. optically focused heating multiple-effect backheat matrix form air wetting dehumidification type solar seawater desalination dress as claimed in claim 1 Put, it is characterised in that the transparent shell (7) uses double-layer transparent vacuum glass tube, be divided into the two semicolumn cavitys in left and right；In Between air channel (12) is done using heat-insulated stainless steel plate；Optical receiver (6) is located at the humidifier chamber (17) of transparent shell (7) in the middle part of device It is interior；Optical receiver (6) is using black column-shaped porous ceramics, and there is hydrophilic film on surface；Also chondritic can be used, Dropbox is placed on (20) on.

3. optically focused heating multiple-effect backheat matrix form air wetting dehumidification type solar seawater desalination dress as claimed in claim 1 Put, it is characterised in that the ventilation converges liquid device (3) positioned at the lower section of every grade of dehumidifying chamber (18) interior dehumidifier (1), spray thrower (4) On, profile is shutter；Ventilation remittance liquid device (3) interior bottom of gullet has water outlet (11), outwards conveys fresh water.