CN212770291U

CN212770291U - Seawater comprehensive utilization system

Info

Publication number: CN212770291U
Application number: CN202021463374.4U
Authority: CN
Inventors: 田江南; 张恬; 吴宇晨; 李红军; 徐淑姣; 周军; 刘军梅
Original assignee: North China Power Engineering Co Ltd of China Power Engineering Consulting Group
Current assignee: North China Power Engineering Co Ltd of China Power Engineering Consulting Group; North China Power Engineering Beijing Co Ltd
Priority date: 2020-07-22
Filing date: 2020-07-22
Publication date: 2021-03-23
Anticipated expiration: 2030-07-22

Abstract

The utility model relates to a seawater comprehensive utilization system, which comprises a pretreatment device, a deep pretreatment device, a heat exchanger, a RO device and a fresh water tank which are sequentially connected with seawater; wherein, the RO device is additionally provided with a pipeline connected with an electrolytic bath which is additionally connected with an evaporation system; steam obtained by evaporation of the evaporation system is returned to the heat exchanger through a pipeline to exchange heat with seawater, and the heat exchanger is additionally provided with a pipeline to send fresh water obtained by steam condensation to the fresh water tank; the utility model has a utilization rate of the seawater up to 100% and no concentrated water is discharged; the heat of the steam generated by the evaporation system can be fully utilized, and the energy is saved; meanwhile, the seawater is electrolyzed into chlorine and hydrogen in the electrolytic cell, so that the comprehensive utilization rate of the seawater is further realized, and the multi-way utilization of the seawater desalination system is realized.

Description

Seawater comprehensive utilization system

Technical Field

The utility model belongs to the water treatment field, concretely relates to sea water desalination field especially indicates a sea water comprehensive utilization system.

Background

The seawater desalination technology originates from the middle of the last century, and through the development of years, the technology is mature at present and the industrialization and scale production are realized. Generally speaking, the seawater desalination technology can be roughly divided into 3 steps: (1) pretreatment of seawater, (2) advanced pretreatment, (3) seawater desalination.

At present, the seawater desalination technology mostly adopts a reverse osmosis membrane separation technology, and the technology has the advantages of simple process, convenient operation, easy control, low operation cost and the like; however, the following problems to be solved have also been raised.

Firstly, the seawater desalination system is single, and the comprehensive utilization degree of seawater is low.

Secondly, the problem of discharging a large amount of concentrated seawater occurs, and the concentrated water after seawater desalination is generally directly discharged to the sea, which can cause the salinity change of local areas of seawater and harm marine organisms.

Therefore, in order to solve the existing problems, the utility model provides a new technical scheme.

SUMMERY OF THE UTILITY MODEL

Following as the utility model discloses preferred technical scheme, but do not regard as right the utility model provides a technical scheme's restriction, through following preferred technical scheme, can be better reach and realize the utility model discloses a technical purpose and beneficial effect.

The technical problem solved by the utility model is to provide a seawater comprehensive utilization system.

The technical means adopted by the utility model are as follows.

A seawater comprehensive utilization system comprises a pretreatment device, a deep pretreatment device, a heat exchanger, an RO device and a fresh water tank which are sequentially connected with seawater.

Wherein, the RO device is additionally provided with a pipeline connected with an electrolytic bath which is additionally connected with an evaporation system; steam obtained by evaporation of the evaporation system is returned to the heat exchanger through a pipeline to exchange heat with seawater, and fresh water obtained by steam condensation is sent to the fresh water tank through another pipeline arranged on the heat exchanger.

Preferably, the RO devices comprise a primary RO device and a secondary RO device connected in series.

Preferably, the pretreatment device is a multimedia filter.

Preferably, the advanced pretreatment device is an ultrafiltration device.

Preferably, the evaporation system is a multi-effect forced circulation evaporator.

Compared with the prior art, the utility model has the following beneficial effects.

(1) The utility model discloses reach 100% to the utilization ratio of sea water, no dense water discharges to the sea.

(2) The heat of the steam generated by the evaporation system is fully utilized, and the energy is saved.

(3) The seawater is electrolyzed into chlorine and hydrogen in the electrolytic cell, so that the comprehensive utilization rate of the seawater is further realized, and the multi-way utilization of the seawater desalination system is realized.

Drawings

Fig. 1 is a schematic view of the flow structure of the present invention.

Detailed Description

The technical solution of the present invention is further explained by the following embodiments with reference to the accompanying drawings. It is obvious that the described embodiments are only some of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without any creative work belong to the protection scope of the present embodiment.

Referring to fig. 1, the flow structure of the present invention is schematically illustrated, and each component used herein is a conventional mature device or apparatus. As shown in the figure, a seawater comprehensive utilization system, it contains: the system comprises a pretreatment device 1, a deep pretreatment device 2, a heat exchanger 3, an RO device 4 and a fresh water tank 5 which are sequentially connected with seawater; wherein, the RO device 4 is additionally provided with a pipeline connected with an electrolytic bath 6, and the electrolytic bath 6 is additionally connected with an evaporation system 7.

Further, steam obtained by evaporation of the evaporation system 7 is returned to the heat exchanger 3 through a pipeline to exchange heat with seawater, and the heat exchanger 3 is additionally provided with a pipeline to condense the steam to obtain fresh water which is sent to the fresh water tank 5.

Furthermore, the RO device 4 further comprises a primary RO device 41 and a secondary RO device 42 connected in sequence, and the concentrated water produced by the primary RO device 41 and the secondary RO device 42 is mixed and then flows into the electrolytic cell 6 together to perform the hydrogen production process by electrolysis.

Furthermore, the pretreatment device 1 adopts a multi-media filter; the deep pretreatment device 2 mostly adopts an ultrafiltration device; the evaporation system 7 is a multi-effect forced circulation evaporator.

When the utility model is used in practice, seawater is collected in a factory and then is firstly pumped to a pretreatment device 1, the pretreatment device 1 is a multi-medium filter, and impurities such as silt, suspended matters and colloid and organisms such as algae in the seawater are removed in the multi-medium filter; then the effluent of the multi-media filter flows into an advanced pretreatment device 2, the advanced pretreatment device 2 is an ultrafiltration device, and suspended matters in the seawater are further removed under the treatment of the ultrafiltration device; the outlet water of the ultrafiltration device is subjected to heat exchange in the heat exchanger and is heated to 15-25 ℃, and the temperature is favorable for the operation of the two-stage RO device.

Therefore, the heated seawater firstly enters the primary RO device 41 for desalination, the fresh water produced by the primary RO device 41 then enters the secondary RO device 42 for treatment, and finally the fresh water produced by the secondary RO device 42 is pumped to the fresh water tank 5 through a pipeline.

Meanwhile, the concentrated water produced by the first-stage RO device 41 and the second-stage RO device 42 flows into the electrolytic tank 6 through a pipeline after being mixed, and the inlet water of the upper-stage unit is further concentrated and electrolyzed in the electrolytic tank 6, so that part of the inlet water of the upper-stage unit is electrolyzed to produce hydrogen and chlorine, the rest of the concentrated water is sent to the evaporation system 7, and the evaporation system 7 removes the salt in the concentrated water to obtain the crystallized salt. And the steam generated by the evaporation system 7 is sent back to the heat exchanger 3 through a pipeline for waste heat utilization. Specifically, the steam and the effluent of the deep pretreatment device 2 exchange heat in the heat exchanger 3 to obtain steam condensate, i.e., fresh water, the heat exchanger 3 is further provided with a pipeline, so that the fresh water produced in the heat exchanger 3 is conveniently introduced into the fresh water tank 5, and the effluent of the heat exchanger 3 is heated to 15-25 ℃ and then sent to a next unit.

In a preferred embodiment of the present invention, the salt content of the seawater is about 30000mg/L, and the seawater is passed through the pretreatment device to remove larger marine organisms and large suspended particles from the seawater, and then flows into the deep pretreatment device. The deep pretreatment device mainly removes suspended matters in seawater, so that the SDI of the effluent is less than 3. And the outlet water of the deep pretreatment device is heated to 15-25 ℃ after passing through the heat exchanger, and the temperature is favorable for the operation of two-stage RO. The utility model discloses in the rate of recovery of one-level RO device is 45%, the rate of recovery of second grade RO device is 85%. When the concentrated water in the electrolytic cell is concentrated to 100000 mg/L, the concentrated water is discharged to an evaporation system.

The utility model has a utilization rate of the seawater up to 100%, and no concentrated water is discharged to the sea; meanwhile, the heat of the steam generated by the evaporation system is fully utilized, and the energy is saved and utilized.

The applicant states that the present invention is described in detail by the above embodiments, but the present invention is not limited to the above detailed method, i.e. the present invention is not meant to be implemented by relying on the above detailed method. It should be clear to those skilled in the art that any improvement of the present invention, to the equivalent replacement of each raw material of the present invention, the addition of auxiliary components, the selection of specific modes, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A seawater comprehensive utilization system is characterized by comprising a pretreatment device (1), a deep pretreatment device (2), a heat exchanger (3), an RO device (4) and a fresh water tank (5) which are sequentially connected with seawater;

wherein the RO device (4) is additionally provided with a pipeline connected with an electrolytic bath (6), and the electrolytic bath (6) is additionally connected with an evaporation system (7);

steam obtained by evaporation of the evaporation system (7) is returned to the heat exchanger (3) through a pipeline to exchange heat with seawater, and fresh water obtained by steam condensation is sent to the fresh water tank (5) through another pipeline arranged on the heat exchanger (3).

2. The seawater comprehensive utilization system of claim 1, wherein the RO apparatus (4) comprises a primary RO apparatus (41) and a secondary RO apparatus (42) connected in series.

3. A seawater comprehensive utilization system as claimed in claim 1, wherein said pretreatment device (1) is a multi-media filter.

4. The seawater comprehensive utilization system of claim 1, wherein the deep pretreatment device (2) is an ultrafiltration device.

5. A seawater comprehensive utilization system as claimed in claim 1, wherein said evaporation system (7) is a multi-effect forced circulation evaporator.