CN107902824A - A kind of sewage disposal system using LNG cold energy - Google Patents
A kind of sewage disposal system using LNG cold energy Download PDFInfo
- Publication number
- CN107902824A CN107902824A CN201711036630.4A CN201711036630A CN107902824A CN 107902824 A CN107902824 A CN 107902824A CN 201711036630 A CN201711036630 A CN 201711036630A CN 107902824 A CN107902824 A CN 107902824A
- Authority
- CN
- China
- Prior art keywords
- sewage
- lng
- cold energy
- oxygen
- level
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/22—Treatment of water, waste water, or sewage by freezing
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/26—Treatment of water, waste water, or sewage by extraction
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B27/00—Machines, plants or systems, using particular sources of energy
Abstract
The invention discloses a kind of sewage disposal system using LNG cold energy, the system can carry out sewage disposal using indirect and/or direct mode using LNG cold energy, wherein indirect processing mode removes sewage impurity by supercritical carbon dioxide extracting, and corresponding system includes supercritical carbon dioxide sewage-treatment plant (12), extraction liquid/gas separator (13), space division system (9) and oxygen-enriched combustion system (10)；Direct processing mode then includes freezing sewage-treatment plant (4) by freezing treated sewage, corresponding system.The present invention is improved by the structure to its key component and its set-up mode and corresponding cold energy use mode etc., it can effectively solve the problem that the problem of natural cold-energy sewage disposal is limited compared with prior art, and the sewage disposal system can also coordinate oxygen-enriched combusting component to use, both LNG cold energy can be made full use of, the zero-emission of carbon is realized again, and environmental protection effect is good.
Description
Technical field
The invention belongs to LNG cold energy uses and technical field of sewage, and LNG cold energy is utilized more particularly, to one kind
Sewage disposal system, which, which corresponds to, directly utilizes LNG cold energy by way of freezing treated sewage and/or indirect utilization
LNG cold energy both modes by way of supercritical carbon dioxide treatment sewage.
Background technology
In recent years, under the background that world community actively increases environment protection, various countries' Natural Gas Consumption Using and its
Shared ratio is continuously improved in primary energy use.Natural gas is by one of main energy sources as 21 century.LNG (that is, liquid
Change natural gas) it is one of important way of current natural gas transportation, in traditional gasification process, the cold that LNG is carried is extra large
Water or air are taken away, and cause about 830kJ/kg colds to be wasted, at the same cause surrounding waters or station area's environment be subject to it is serious cold
Pollution.Therefore, Devoting Major Efforts To Developing LNG cold energy, improving cold energy use rate has very high Social benefit and economic benefit.
With expanding economy, the sewage of Chinese annual required processing is also more and more, at present the annual required processing in China
Sewage is up to more than 700 hundred million tons.Sewage water treatment method freezing emerging at present need not consume electric energy, can save mass energy, it is dirty
Water treatment procedure needs to stablize cold energy., can be with if LNG cold energy is used to herein, can not only to improve the cold energy use rate of LNG
Largely stable cold energy is provided for freezing.According to water purifying principle is freezed, pollutant will be ostracised in refrigerating process
Into subglacial water body, freezing has the pollutant in water body certain concentration effect, Chinese patent application CN201010104868
Disclosure of the invention one is using including wind energy, solar energy, the sewage and wastewater treatment system of cold energy natural energy.The system energy treated sewage,
But low-temperature receiver is natural cooling source in freezing in system, and cold is uncontrollable, and it is to pass through icing sewage in its sewage disposal process
The mode of injection sleet separates.The finiteness and sewage separate mode of its low-temperature receiver determine that the system can only handle limited sewage.
On the other hand, supercritical CO2Sewage treatment, supercritical CO2To a large amount of organic solvents used in industrial production,
Chemical reaction, the raw material in building-up process, solvent etc. have special dissolution；If in supercritical CO2In add
Polarity modifier, can also make other materials in supercritical CO2In solubility greatly increase.So supercritical CO2To extracting sewage
In pollutant there is good effect.Because CO2It is nontoxic, nonflammable；Again because of supercritical CO2Sewage disposal process is simple so that
This technology is increasingly favored be subject to people.Supercritical CO involved in the prior art2The relevant apparatus of sewage treatment and side
Method, is required to individually produce supercritical carbon dioxide, high energy consumption.
The content of the invention
For the disadvantages described above or Improvement requirement of the prior art, it is an object of the invention to provide one kind to utilize LNG cold energy
Sewage disposal system, wherein passing through the structure to its key component and its set-up mode and corresponding cold energy use mode
Etc. being improved, the problem of natural cold-energy sewage disposal is limited can effectively solve the problem that compared with prior art, and at the sewage
Reason system can also coordinate oxygen-enriched combusting component to use, and can not only make full use of LNG cold energy, but also realize the zero-emission of carbon, environmental protection effect
It is good.
To achieve the above object, a kind of one side according to the invention, there is provided sewage disposal system using LNG cold energy
System, it is characterised in that including supercritical carbon dioxide sewage-treatment plant (12), extraction liquid/gas separator (13), space division system
(9) and oxygen-enriched combustion system (10), wherein,
The space division system (9) is connected by First Heat Exchanger with LNG sources (1), for the cold energy effect in original LNG
Under isolated liquid oxygen and gaseous nitrogen, original LNG carried out to the nitrogen in forced air and oxygen then absorb heat to obtain through level-one
Natural gas after level-one utilization；
The second heat exchanger is provided with the oxygen-enriched combustion system (10), second heat exchanger be used for the liquid oxygen into
Row, which changes, is thermally treated resulting in gaseous oxygen；The oxygen-enriched combustion system (10) is then used to carry out oxygen-enriched combustion under the action of the gaseous oxygen
Burning obtains flue gas CO2；
The 3rd heat exchanger is provided with the supercritical carbon dioxide sewage-treatment plant (12), the 3rd heat exchanger is used for
By the flue gas CO under the action of natural gas after level-one utilization2It is transformed into supercritical CO2；The overcritical titanium dioxide
Carbon sewage-treatment plant (12) is connected with the oxygen-enriched combustion system (10), and in the supercritical CO2As extractant
Under conditions of sewage is extracted, obtain sewage impurity reduction clean water and sewage impurity enriched extract, it is described
Natural gas after level-one utilizes absorbs heat to obtain the natural gas after two level utilizes through two level；
The supercritical carbon dioxide sewage-treatment plant (12) is also connected with the extraction liquid/gas separator (13), the extraction
Liquid/gas separator (13) is taken to be used for the CO in the extract2Separated with sewage impurity, isolated CO2Then it is passed through institute
State circulation in oxygen-enriched combustion system (10) and participate in oxygen-enriched combusting reaction；
The sewage disposal system integral cascade make use of LNG cold energy, be the original LNG is absorbed heat to obtain through level-one it is described
Natural gas after level-one utilization, then the natural gas after level-one utilization is natural after two level absorbs heat to obtain the two level utilization
Gas, produces and make use of intermediate product supercritical CO2Realize processing and the CO of sewage2Recycle.
As present invention further optimization, the natural gas after the two level utilizes also heats up through air heater, is used for
It is passed through in the oxygen-enriched combustion system (10) and participates in oxygen-enriched combusting reaction, or for being incorporated to gas ductwork.
As present invention further optimization, its temperature of natural gas after the level-one utilizes is -120 DEG C~-60 DEG C,
Its temperature of natural gas after the two level utilizes is -30 DEG C~10 DEG C.
As present invention further optimization, the flue gas CO2It is first to be passed through condenser to carry out removing moisture solution；The profit
Carbon capture system (11) is further included with the sewage disposal system of LNG cold energy, for the flue gas CO after removing moisture solution2, wherein
Part of smoke CO2It is transformed into the supercritical CO2, second heat exchanger is then used for remaining partial fume CO2With
The liquid oxygen, which change, is thermally treated resulting in liquid CO2, the carbon capture system (11) is then for liquid CO2Captured,
Captured so as to fulfill carbon.
As present invention further optimization, this is further included at freezing sewage using the sewage disposal system of LNG cold energy
Device (4) is managed, which includes compressor, the 4th heat exchanger, freezing pond, coil pipe and mechanical ice-breaking
Component, wherein,
The compressor is connected with the LNG sources (1), and the original LNG for being exported to the LNG sources (1) adds
Pressure；4th heat exchanger is connected with the compressor, and the 4th heat exchanger has refrigerant, after using the refrigerant and pressurization
LNG carry out heat exchange, refrigerant after heat exchange be then used for by the coil pipe with it is described freeze accommodated in pond wait to locate
Reason sewage carry out heat exchange cause the treatment sewage occur freeze concentration obtain the reduction of sewage impurity upper part and
The lower part layers of ice of sewage impurity enriched；The machinery ice-breaking component is then used to carry out separating treatment to the layers of ice, remaining
Upper part be the processing water obtained after corresponding chilled method processing.
It is another aspect of this invention to provide that the present invention provides a kind of sewage disposal system using LNG cold energy, its feature
It is, including freezing sewage-treatment plant (4), the freezing sewage-treatment plant (4) include compressor, heat exchanger, freezing
Pond, coil pipe and mechanical ice-breaking component, wherein,
The compressor is connected with LNG sources (1), and the original LNG for being exported to the LNG sources (1) pressurizes；It is described
Heat exchanger is connected with the compressor, which has refrigerant, for carrying out hot friendship using the refrigerant and the LNG after pressurization
Change, the refrigerant after heat exchange is then used to carry out hot friendship with the treatment sewage accommodated in the freezing pond by the coil pipe
Change so that the treatment sewage occurs freeze concentration and obtains the upper part and sewage impurity enriched of sewage impurity reduction
Lower part layers of ice；The machinery ice-breaking component is then used to carry out the layers of ice separating treatment, and remaining upper part is pair
The processing water for answering chilled method to be obtained after handling.
As present invention further optimization, the sewage that is obtained after the chilled method processing be additionally operable to circulation be passed through it is described
Freeze in pond, multiple freeze concentration processing is carried out, so that the clean water after obtaining the processing that sewage impurity further reduces.
By the contemplated above technical scheme of the present invention, compared with prior art, LNG cold energy is utilized in the present invention
Sewage disposal system, it may include two independent sewage treatmentmethods, one of which are directly used in freezing dirt for LNG cold energy
Water process, another kind are indirectly for supercritical carbon dioxide sewage disposal for LNG cold energy, both can all be individually present, also can phase
Mutually combination.LNG cold energy is directly used in the device heat exchanger and is provided for freezing sewage-treatment plant in freezing sewage disposal
Cold energy, sewage are passed through freezing sewage-treatment plant after freezing, and concentrate and low is classified into according to freezing principle sewage
Contaminant water, low-pollution water handle to obtain clean water by multiple freeze cycle again.And in supercritical carbon dioxide sewage disposal
LNG cold energy carries out cascade utilization (i.e. level-one heat absorption is utilized using absorbing heat with two level)：Cold energy is used for sky by the heat exchange of LNG level-ones first
Subsystem, high concentration O is provided for oxygen-enriched combusting2, LNG cold energy secondary heat exchange is by a part of CO in combustion product gases2Cooling is produced super
Critical CO2, sewage is handled for entering in supercritical carbon dioxide sewage-treatment plant, also, overcritical titanium dioxide
Carbon sewage-treatment plant is connected with extraction liquid/gas separator, and sewage passes through supercritical CO2Clean water, extract are obtained after the completion of extraction
CO is isolated in decompression in liquid/gas separator is extracted2(extract separator specifically separates CO2And obtain sewage impurity), the part
CO2Enter combustion chamber by smoke circulating system to neutralize the high temperature that burning produces.The cold energy of oxygen can pass through the after space division
Two heat exchangers (heat exchanger may be provided in oxygen-enriched combustion system) and another part CO2Exchange heat, afterwards CO2It can be captured in carbon and be
It is captured in system.
In the case of indirect utilization, the present invention is to produce supercritical CO using LNG cold energy2, indirect utilization LNG cold energy leads to
Cross supercritical CO2Treatment by extraction sewage；After the completion of sewage disposal, the pressure for reducing extract isolates CO2, and be passed into
Smoke circulating system is used in oxygen-enriched combustion system and ignition temperature；And the supercritical CO of solute (i.e. sewage impurity) is extracted2
Into after extraction liquid/gas separator, the reduction of its solubility, CO can be made by reducing the pressure of extract2From device top after gasification
Extraction, by smoke circulating system, for neutralizing the ignition temperature of oxygen-enriched combusting combustion chamber.The present invention is preferably by setting carbon
Capture component, the cold energy that the LNG after being utilized using level-one is contained, on the one hand can make full use of the cold energy of LNG, on the other hand
The carbon emission of total system can be reduced again, it is more environmentally-friendly.Supercritical CO in the present invention2Sewage treatment can be with indirect utilization LNG
Cold energy, can also solve the problems, such as the carbon emission of Natural Gas Power Plant flue gas.LNG cold energy uses cascade utilization mode, this will improve LNG
The utilization ratio of cold energy.The cold energy that LNG level-ones exchange heat can be used for space division, the O that space division is produced first2For oxygen-enriched combusting, combustion
Burn the part CO produced2Supercritical CO is produced using the cold energy of LNG secondary heat exchanges2, for treated sewage, particularly Industry Waste
Water.In the case of directly utilizing, the LNG cold energy sewage disposal systems in the present invention are provided largely for freezing using LNG
Stablize cold energy, can be pre-processed or purified (for example, using only once freezing) to sewage, and it is (i.e. repeatedly) cold using multistage
Jelly method treated sewage can obtain the further lowering of clean water of sewage impurity content.
In the case of indirect utilization, the present invention is also by absorbing heat level-one to obtain the natural gas after level-one utilizes, two level
The temperature that heat absorption obtains both natural gases after two level utilizes optimizes, and utilizes their cooperations with shunt assembly, Neng Gougeng
Good utilizes cold energy, reaches using maximizing, and original LNG is total after level-one utilizes and two level utilizesIt is more efficient.
The present invention can the effectively good CO produced using oxygen-enriched combusting2Flue gas, and by its effective and sewage
Reason combines.In supercritical CO2During treated sewage, the present invention successfully make use of LNG cold energy, whole sewage disposal process
Without consuming other energy again, a self-centered circulatory system is completed.And in the present system, LNG cold energy is implemented
Cascade utilization mode, which substantially increase the utilization rate of cold energy, avoid the loss of energy.And because cold energy is step profit
With temperature difference of heat exchanger reduces, and the requirement to equipment is also lower, therefore the service life of equipment also can be longer.This indirect utilization LNG cold energy
Sewage disposal system, cascade utilization LNG cold energy on the whole, i.e. first absorb heat original LNG obtain after level-one utilizes through level-one
Natural gas, then natural gas after the level-one is utilized absorbs heat to obtain the natural gas after two level utilizes through two level, produces and utilizes
Intermediate product supercritical CO2Realize processing and the CO of sewage2Recycle.
The present invention is by setting the freezing sewage with compressor, heat exchanger, freezing pond, coil pipe and mechanical ice-breaking component
Processing unit, utilizes the overall co-ordination between various components so that this has sewage using the sewage disposal system of LNG cold energy
Handle the advantages of convenient, the compressor in device is used for LNG pressurizations (because follow-up natural gas is used to burn or grid-connected
Pressure is higher, and overall energy loss of pressurizeing before heat exchange can smaller), the LNG that then pressurizes exchanges heat with refrigerant, refrigerant by coil pipe again with dirt
Water heat exchange (why using refrigerant, if allowing for the excessive temperature differentials between direct heat transfer equipment, damages the use of equipment
Service life), by icebreaking device ice-breaking, (icebreaking device can highly cut ice cube and obtain according to a certain percentage after treating sewage the ice formed
Pretreated water or clean water), and it is further to utilize multistage (i.e. repeatedly) freezing treated sewage to can obtain sewage impurity content
Decline clean water (for example, can by it is multiple freezing the freezing processings of pond one time obtain pretreating sewage, after by it is the plurality of freezing pond it is pre-
The sewage of processing focuses in a new freezing pond and obtains cleaner water by second of freezing processing).In this set system
Freezing directly can pre-process large amount of sewage using the cold energy of LNG, or direct treated sewage, low-temperature receiver are more sufficient
Stablize, the cold energy contained is also considerably beyond natural cold-energy.Therefore LNG cold energy is applied to sewage treatment field, can not only dropped
The processing cost of low sewage, can also solve the Utilizing question of LNG cold energy.Sewage can be carried out circular treatment by the system, can be carried
The effect of high sewage disposal, makes the system reach the COD removal rates of higher.
The present invention using both modes with indirect utilization by that directly can make full use of all types of LNG stations (such as LNG points
For, LNG gasification station, LNG receiving stations, LNG power plant etc.) in cold energy, particularly in refrigeration duty little period or region, and
The system sewage treating efficiency is high, its COD removal rate can reach more than 90%, can save a large amount of electricity consumptions, great environmental protection valency
Value, there is good development prospect.LNG can heat up after cold energy use and become natural gas NG, NG can be used for burning, as this hair
Bright middle oxygen-enriched combustion system can be using NG as fuel, and certainly, NG also may be incorporated into gas ductwork.
Greenhouse effects constantly aggravate at present, and carbon emission pressure is increasing, to solve the problems, such as global warming, zero carbon row
Put into one of optimal selection.The set system, removes the CO for being used for producing into supercriticality2Circulation is participated in, it is remaining
CO2Can be all captured collection, not have any carbon emission, environmentally protective, can greatly alleviate the trend of global warming, be reduced
Environmental pressure.
Two kinds of LNG cold energy uses technologies of the present invention are directly utilization and indirect utilization, are sufficiently utilized from different angles
The cold energy of LNG, and can be directed to different LNG stations, using different Land use systems, utilization to LNG cold energy it is more effective (with
Exemplified by indirect utilization device with oxygen-enriched combusting component, oxygen-enriched combusting component is often suitable for LNG power plant, LNG amounts also bigger；
And for small-sized LNG stations such as LNG points confession, LNG satellite stations etc., since it does not have oxygen-enriched combusting component, this hair can be used
Bright middle freezing is corresponding directly to utilize device).It make use of LNG cold energy treated sewages in system, avoiding the same of cold pollution
When, also water quality is purified, ecological environment is improved, improves city taste, maintains or recovered the good water in city
Environment, to promote a conservation culture, society is made that positive contribution.
As it can be seen that the present invention has, capacity usage ratio is high, energy conservation and environmental protection, and the characteristic such as zero carbon emission, also has in sewage disposal
Good development prospect.Its advantage has：
1st, it is efficient to realize LNG cold energy directly or indirectly utilization and cascade utilization, LNG cold energy uses for system.
2nd, system zero carbon emission, energy conservation and environmental protection.
3rd, system low-temperature receiver is derived from a wealth of sources and stablized, beneficial to the longtime running of sewage disposal.
4th, two kinds of sewage water treatment method treated sewage COD removal rates can reach more than 90%.
How LNG cold energy uses to be got up is difficult point in present invention research and development, because to waste situation tight for LNG cold energy at present
Weight, is entirely direct gasification, is not only avoided that cold pollution if can efficiently use, can also produce economic benefit.In the prior art
Some freezings are without constant cold energy, and freezing is since its cold energy problem cannot solve, so using not being promoted；And this hair
Bright combination liquefied natural gas, the use of natural gas is just being widelyd popularize with reference to current country, and LNG is important means of transportation,
Therefore the usage amount of LNG is also original more, the present invention has a good application prospect.
In addition supercritical carbon dioxide sewage is research hotspot emerging recently, its effect of extracting is all being studied, but
Be be also it is rare have to its producing process it is of interest；System in the present invention is not only suitable for treated sewage, but also can supplement LNG amounts
One step of productionization, cleverly needs CO by sewage disposal2CO is needed with oxygen-enriched combusting2With reference to that is, by sewage disposal and LNG power plant
Combine, while carbon capture component can be further set again, cold energy is captured for carbon.As it can be seen that the present invention both solves two
Carbonoxide carrys out source problem, while solves the problems, such as the low-temperature receiver in carbon dioxide preparation, and the excessive carbon dioxide that system produces
Can be captured collection.
Brief description of the drawings
Fig. 1 is integrated system flow diagram of the present invention.
The implication of each reference numeral is as follows in figure：1-LNG, 2-NG, 3-gas ductwork, 4-freezing sewage disposal dress
Put, 5-concentrate, 6-low-pollution water, 7-clean water, 8-cesspool, 9-space division system, 10-oxygen-enriched combustion system,
11-carbon capture system, 12-supercritical carbon dioxide sewage-treatment plant, 13-extraction liquid/gas separator, 14-sewage impurity.
Embodiment
In order to make the purpose , technical scheme and advantage of the present invention be clearer, with reference to the accompanying drawings and embodiments, it is right
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.As long as in addition, technical characteristic involved in each embodiment of invention described below
Not forming conflict each other can be mutually combined.
All things considered, the present invention are provided using the sewage disposal system structure of LNG cold energy including LNG (1) for the system
LNG cold energy, the NG (2, i.e. natural gas) after heating can be that fuel is provided in oxygen-enriched combustion system (10), and remainder may be incorporated into
Gas ductwork (3).LNG cold energy can be directly used in freezing sewage-treatment plant (4), can also be indirectly for surpassing by LNG cold energy
Critical carbon dioxide sewage-treatment plant (12).Wherein freezing sewage-treatment plant (4) utilizes LNG cold energy by cesspool (8)
In send sewage cooling freeze, and using artificial freezing principle purification water quality, sewage is divided into low-pollution water part (6)
With concentrate part (5), low-pollution water (5) is sent into freezing sewage-treatment plant (4) circular treatment again, until obtaining clean
Water purification (7).Wherein LNG cold energy uses cascade utilization form in supercritical carbon dioxide sewage treatment, and LNG first (1) adds
Exchange heat after pressure in space division system (9) with forced air (superatmospheric), according to the different separation O of component boiling point in air2
And N2, separated O2CO of the condensation for carbon capture system (11) into the second heat exchanger2(separated low temperature N2System can be used as
The raw material of standby liquid nitrogen), oxygen absorbs heat, carbon dioxide heat release, afterwards O2Together it is sent into natural gas in oxygen-enriched combustion system (10)
Burn, and be passed through the CO that supercritical extract is completed to separate afterwards2For neutralizing ignition temperature.In combustion product gases
CO2It is divided into two parts, a part of CO after condenser removes moisture2Second be first sent into oxygen-enriched combustion system (10)
N after heat exchanger, with space division2And O2Heat exchange cooling, afterwards pressurization are permanently captured by the carbon system (11) capture and collect, another part CO2
Into supercritical carbon dioxide sewage-treatment plant (12), secondary heat exchange is carried out with LNG (1), produces supercritical CO2, for dirt
The extraction of aqueous solution.Extract and clean water are classified into after extraction in mixer, isolates clean water, extract then enters extraction
In liquid/gas separator (13) CO is carried out using voltage drop method2With the separation of sewage impurity (14), the CO that will be separated afterwards2It is passed through richness
Oxygen combustion system (10).
The gas ductwork (3) be achieved in that natural gas by air heater be heated to room temperature (such as 15 DEG C~
25 DEG C) after be incorporated to gas ductwork (such as city dweller's gas ductwork).
The freezing sewage-treatment plant (4) is by compressor, heat exchanger, freezing pond, coil pipe and mechanical ice-breaking dress
Put composition.LNG (1) pressurizes by compressor, is passed through in heat exchanger, is changed with the refrigerant (such as iso-butane) in heat exchanger afterwards
Heat, refrigerant exchange heat in pond is freezed with sewage again.Sewage removes the debris of large volume through preliminary filtering, so that it may enters freezing
Rely on the cold energy of refrigerant in coil pipe to carry out freeze concentration in pond, according to the principle of freezing, waste water impurity will the latter half into
Row concentration, after water freezing to the certain thickness in pond is freezed, crushes ice cube by machine power and is separated, its middle and upper part point
Ice cube is required clean parts, and lower part impurity part is uniformly processed.
The space division system (9) is made of compressor, heat exchanger and separator.Air is laggard by compressor boost
Enter heat exchanger, temperature is reduced to O under the pressure condition after exchanging heat with LNG (1)2With N2Boiling point between value, separation is different afterwards
The N of state2With O2。
The oxygen-enriched combustion system (10) is by the second heat exchanger, compression pump, air heater, heat exchanger, separator, combustion
Burn room composition, oxygen-enriched combustion system (10) for follow up device provide needed for high concentration CO2.Exist in oxygen-enriched combustion system (10)
The CO of different conditions2, wherein by close to the CO of critical-temperature2Supercritical carbon dioxide sewage-treatment plant (12) is supplied to, will be low
Warm liquid CO2It is supplied to carbon capture system (11).Gaseous state N after air separation2By being sent into the after being discharged at the top of gas-liquid separator
Two heat exchangers exchange heat, and liquid nitrogen is can be treated to be after heat exchange and collects use；And the liquid oxygen after space division enters from another entrance
Second heat exchanger together participates in exchanging heat.In the O after the heating of the second heat exchanger2Room temperature shape is heated into air heater
State, is re-fed into combustion chamber and participates in combustion reaction, and the high-temperature flue gas of burning is used for micro- steam/gas turbine/combined cycle hair
Electricity.On the other hand, LNG is warming up to normal temperature state by being passed through air heater again after heat exchanger, be sent into afterwards combustion chamber into
Row combustion reaction；It if the natural gas after gasification has surplus, can be shunted by separator, remaining NG (2) is sent into combustion gas
Pipe network (3).The logistics of combustion chamber is entered except O2With the CO for also having circulation beyond natural gas2, part CO2For overcritical two
In carbonoxide sewage-treatment plant (12) CO separated is depressured after the completion of extraction2, pass through flue gas recirculation after separation completion
System enters combustion chamber, for neutralizing the ignition temperature of combustion chamber.
The carbon capture system (11) is made of compressor, heat exchanger, storage tank, (10) flue gas in oxygen-enriched combustion system
CO2After condensation removes water, a part is directly used in the CO of supercritical carbon dioxide sewage-treatment plant circulation2, remainder warp
Become low temperature liquid CO after crossing the second heat exchanger2, it is sent into after being pressurizeed by compressor in storage tank and stores capture.
The supercritical carbon dioxide sewage-treatment plant (12) be by heat exchanger, mixer, compressor set into.By
A part of CO of current divider2After compressor pressurizes, then it is passed through heat exchanger and carries out secondary heat exchange with LNG (1), is passed through afterwards mixed
In clutch, valve regulation is adjusted to supercriticality by the pressure and temp in mixer, is passed through sewage in mixer afterwards with surpassing
Critical CO2Contact is extracted, and is separated extract with clean water by discharge outlet after the completion of extraction, extract is passed through extraction
Take liquid separating apparatus (13).
The extraction liquid separating apparatus (13) is made of expansion valve, separator, pressure-regulating valve.When having extracted solute
Supercritical fluid by expansion valve enter extraction liquid/gas separator after, pressure reduce, CO2Gasification, is extracted component overcritical
Solubility in fluid, which reduces, to be separated out.Solute is taken out by separator lower part, the CO after decompression2Combustion is passed through by smoke circulating system
Burn the high temperature that in room and burning produces.
As it can be seen that the device can be directed to the CO of different conditions2, after flue gas condensing, temperature is higher after carbon dioxide condensing,
Certain proportion (can according to needed for sewage proportion adjustment) can be separated, with the LNG once to exchange heat (temperature is higher than the oxygen after space division)
After carrying out secondary heat exchange, it is appropriate for producing supercritical carbon dioxide；Remaining carbon dioxide is also not suitable for carbon because of temperature height
Capture, the oxygen after lucky space division cannot burn because temperature is too low, and after exchanging heat with carbon dioxide, and oxygen temperature rises can be with
For burning, carbon dioxide temperature, which declines, can be used for carbon capture.
Some control valves can be arranged as required on various pipelines, are not repeated here.
It is freezing sewage disposal embodiment below：
- 162 DEG C of temperature, the LNG that pressure is 0.1MPa pressurize from LNG storage tank into compressor, and moulding pressure can be according to reality
Border situation determines that LNG carries out multi-stage heat exchanger with heat exchanger after pressurization.Natural gas temperature after the completion of heat exchange rises to -20 DEG C, then
Heat exchange gas is warming up to by 20 DEG C of room temperature by air heater, is sent into combustion chamber burns or be incorporated to gas ductwork afterwards.
The refrigerant iso-butane of heat exchange is reduced to -50 DEG C from -12 DEG C, then exchanges heat with the sewage in the device so that dirty
Coolant-temperature gage is reduced to -5 DEG C from 20 DEG C, and the refrigerant after heating continues and LNG heat exchange cycles.
It is using machine power that upper strata ice cube is broken apart, it can obtain clean water after melting.If desired obtain more pure
Net water, can carry out aforesaid operations again by melt water.
According to calculating, 1Nm3LNG can handle 1.2kg sewage.Then understand, be 3~50,000 Nm for air demand3/ day
Small-sized LNG points supply, and whole year can handle more than 10,000 tons sewage；It is 10~150,000 Nm for a scale3The medium-sized city LNG of/day
Gasification station, whole year can handle about 5.6 ten thousand tons of sewage；It is 1,200,000,000 Nm for urban electricity supply year gas consumption3LNG power plant, whole year can
Handle about 128.8 ten thousand tons of sewage；Harbour is received for the LNG in city, its year air demand can be located up to 84 billion cubic meters, whole year
About 901.6 ten thousand tons of sewage are managed, there is the high value of environmental protection and economic benefit.
It is supercritical carbon dioxide sewage disposal embodiment below：
- 162 DEG C of temperature, pressure are that the LNG of 0.1MPa is forced into 3.5MPa from LNG storage tank into compressor, are being changed afterwards
Exchange heat in hot device with being compressed to the air of 0.6MPa, compressed air is reduced to -153 DEG C, after the heat exchange of LNG level-ones from 30 DEG C
Pressure is constant, and temperature is improved to -95 DEG C from -162 DEG C.
Air isolates pure oxygen in space division system, and is together passed through in the second heat exchanger and exchanges heat with nitrogen, afterwards O2Rise
High pressure enters back into air heater equipressure and is heated to room temperature to 3.5MPa, with the natural gas of 3.5MPa in a combustion chamber into
Row oxygen-enriched combusting, oxygen is isolated by space division system, wherein O2Mole fraction is 31%, and the flue-gas temperature of burning is
1300℃。
High-temperature flue gas is used for micro- steam/gas turbine/combined cycle generation, and temperature reduces most 120 DEG C after flue gas heat exchange,
Enter afterwards in condenser condensation and separation of moisture, flue gas main component is CO at this time2。
Part CO29.0MPa being forced into by compressor, and with LNG and carrying out secondary heat exchange, natural gas temperature rises to-
20 DEG C, CO2Temperature is reduced to 40 DEG C, at this time by CO2It is passed through in mixer, is adjusted by automatically controlling to supercriticality,
And it is passed through sewage and is extracted.
Remaining CO2It is passed through in the second heat exchanger, with the O after space division2Exchange heat, 30 DEG C of gaseous state CO2Condensation becomes -80
DEG C liquid CO2, storage tank store collected is utilized after being forced into 2.2MPa.
Sewage and supercritical CO in mixer2Contact extraction, by discharge outlet by extract and clean water after the completion of extraction
Separated, extract enters extraction liquid separating apparatus.
Extract in liquid separating apparatus, extract pressure is reduced to 3.5MPa, and it is molten in supercritical fluid to be extracted component
Xie Du is reduced, and it is separated out in separator and is separated.The CO isolated2It is used for the height for neutralizing burning generation into flue gas recirculation
Temperature.
As it can be seen that LNG is for freezing sewage treatmentmethod in the present invention, first by the liquefied natural gas in LNG storage tank
Exchange heat after pressurization with refrigerant, refrigerant exchanges heat with freezing sewage-treatment plant afterwards, and sewage is carried out to be cooled to knot
Ice, according to the principle of freezing, waste water impurity will be concentrated in the latter half, then be retained afterwards with mechanical icebreaking device separation
The low-pollution water of top half, removes the latter half and focuses on.Low-pollution water can be passed through to freezing again after the completion of processing
Circular treatment is carried out in method sewage-treatment plant, reaches discharge standard to water quality.
It is the cascade utilization mode that used to LNG cold energy that LNG cold energy, which is used for supercritical carbon dioxide sewage treatmentmethod, first
Exchange heat after first LNG pressurization with forced air, afterwards again with flue gas CO2Carry out secondary heat exchange.Air after cooling utilizes N2With
O2Boiling point different carry out air separation.N after separation2And O2CO is condensed into the second heat exchanger2For carrying out carbon capture,
O afterwards2, natural gas and circulation CO2(it is fed again into after participating in the extraction of supercritical carbon dioxide sewage in combustion chamber, for neutralizing
Ignition temperature) oxygen-enriched combusting is carried out in a combustion chamber, contain in combustion chamber and be used to neutralize ignition temperature.The high-temperature flue gas of combustion reaction
For micro- steam/gas turbine/combined cycle generation, flue gas is condensed by condenser afterwards, and the moisture in flue gas all liquefies,
Isolate CO2, the CO afterwards2It is split as two parts：A part of CO2After pressurization supercritical CO is produced with LNG secondary heat exchanges2；
Another part is passed through the second heat exchanger and the N after space division again2And O2Heat exchange cools down, afterwards part CO2Captured recycling profit
With.CO in overcritical device after pressurization cooling2Be passed through in mixer, adjusted in mixer to supercriticality, then with waste water
Mixing is extracted, and is classified into extract and clean water after the completion of extraction in mixer, is isolated clean water, extract is then sent into
Extract in liquid/gas separator.In liquid/gas separator is extracted, extract isolates CO by voltage drop method2, CO2By being recycled into burning
Room is used to neutralize Indoor Combustion temperature.
In the present invention, in heat exchanger front end, if their temperature of two or more materials of heat to be exchanged is unsatisfactory for
Heat exchange conditions, can suitably increase pressurization/decompressor.
As it will be easily appreciated by one skilled in the art that the foregoing is merely illustrative of the preferred embodiments of the present invention, not to
The limitation present invention, all any modification, equivalent and improvement made within the spirit and principles of the invention etc., should all include
Within protection scope of the present invention.
Claims (7)
1. a kind of sewage disposal system using LNG cold energy, it is characterised in that including supercritical carbon dioxide sewage-treatment plant
(12), liquid/gas separator (13), space division system (9) and oxygen-enriched combustion system (10) are extracted, wherein,
The space division system (9) is connected by First Heat Exchanger with LNG sources (1), is added under being acted in the cold energy of original LNG Duis
The nitrogen in air and oxygen is pressed to carry out isolated liquid oxygen and gaseous nitrogen, original LNG then absorbs heat to obtain level-one profit through level-one
Natural gas after；
The second heat exchanger is provided with the oxygen-enriched combustion system (10), which is used to change the liquid oxygen
It is thermally treated resulting in gaseous oxygen；The oxygen-enriched combustion system (10) is then used for the progress oxygen-enriched combusting under the action of the gaseous oxygen and obtains
To flue gas CO2；
The 3rd heat exchanger is provided with the supercritical carbon dioxide sewage-treatment plant (12), the 3rd heat exchanger is used in institute
State the flue gas CO under the action of the natural gas after level-one utilizes2It is transformed into supercritical CO2；The supercritical carbon dioxide is dirty
Water treatment facilities (12) is connected with the oxygen-enriched combustion system (10), and in the supercritical CO2Bar as extractant
Sewage is extracted under part, obtains the clean water of sewage impurity reduction and the extract of sewage impurity enriched, the level-one
Natural gas after utilization absorbs heat to obtain the natural gas after two level utilizes through two level；
The supercritical carbon dioxide sewage-treatment plant (12) is also connected with the extraction liquid/gas separator (13), the extract point
It is used for from device (13) to the CO in the extract2Separated with sewage impurity, isolated CO2Then it is passed through described oxygen-enriched
Circulation participates in oxygen-enriched combusting reaction in combustion system (10)；
The sewage disposal system integral cascade make use of LNG cold energy, be to absorb heat the original LNG through level-one to obtain the level-one
Natural gas after utilization, then the natural gas by the natural gas after level-one utilization after two level absorbs heat to obtain the two level utilization,
Produce and make use of intermediate product supercritical CO2Realize processing and the CO of sewage2Recycle.
2. the sewage disposal system of LNG cold energy is utilized as claimed in claim 1, it is characterised in that the day after the two level utilization
Right gas also heats up through air heater, and participates in oxygen-enriched combusting reaction for being passed through in the oxygen-enriched combustion system (10), or uses
In being incorporated to gas ductwork.
3. the sewage disposal system of LNG cold energy is utilized as claimed in claim 1, it is characterised in that the day after the level-one utilization
Its temperature of right gas is -120 DEG C~-60 DEG C, its temperature of natural gas after the two level utilizes is -30 DEG C~10 DEG C.
4. the sewage disposal system of LNG cold energy is utilized as described in claim 1-3 any one, it is characterised in that the flue gas
CO2It is first to be passed through condenser to carry out removing moisture solution；This further includes carbon capture system using the sewage disposal system of LNG cold energy
(11), for the flue gas CO after removing moisture solution2, a portion flue gas CO2It is transformed into the supercritical CO2, described
Two heat exchangers are then used for remaining partial fume CO2With the liquid oxygen change and be thermally treated resulting in liquid CO2, the carbon catches
System (11) is obtained then to be used for liquid CO2Captured, captured so as to fulfill carbon.
5. the sewage disposal system of LNG cold energy is utilized as described in claim 1-4 any one, it is characterised in that this utilizes LNG
The sewage disposal system of cold energy further includes freezing sewage-treatment plant (4), which includes compression
Machine, the 4th heat exchanger, freezing pond, coil pipe and mechanical ice-breaking component, wherein,
The compressor is connected with the LNG sources (1), and the original LNG for being exported to the LNG sources (1) pressurizes；Institute
State the 4th heat exchanger with the compressor to be connected, the 4th heat exchanger has refrigerant, for utilizing the refrigerant and the LNG after pressurization
Heat exchange is carried out, the refrigerant after heat exchange is then used to freeze the treatment sewage accommodated in pond with described by the coil pipe
Carry out heat exchange cause the treatment sewage occur freeze concentration obtain the reduction of sewage impurity upper part and sewage it is miscellaneous
The lower part layers of ice of matter enrichment；The machinery ice-breaking component is then used to carry out separating treatment, remaining top to the layers of ice
The processing water obtained after the i.e. corresponding chilled method processing in part.
6. a kind of sewage disposal system using LNG cold energy, it is characterised in that including freezing sewage-treatment plant (4), this is cold
Jelly method sewage-treatment plant (4) includes compressor, the 4th heat exchanger, freezing pond, coil pipe and mechanical ice-breaking component, wherein,
The compressor is connected with LNG sources (1), and the original LNG for being exported to the LNG sources (1) pressurizes；Described 4th changes
Hot device is connected with the compressor, and the 4th heat exchanger has refrigerant, for carrying out hot friendship using the refrigerant and the LNG after pressurization
Change, the refrigerant after heat exchange is then used to carry out hot friendship with the treatment sewage accommodated in the freezing pond by the coil pipe
Change so that the treatment sewage occurs freeze concentration and obtains the upper part and sewage impurity enriched of sewage impurity reduction
Lower part layers of ice；The machinery ice-breaking component is then used to carry out the layers of ice separating treatment, and remaining upper part is pair
The processing water for answering chilled method to be obtained after handling.
7. the sewage disposal system of LNG cold energy is utilized as claimed in claim 6, it is characterised in that after the chilled method processing
Obtained processing water is additionally operable to circulation and is passed through in the freezing pond, multiple freeze concentration processing is carried out, so as to obtain sewage impurity
Clean water after the processing further reduced.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711036630.4A CN107902824B (en) | 2017-10-30 | 2017-10-30 | Utilize sewage treatment system of LNG cold energy |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711036630.4A CN107902824B (en) | 2017-10-30 | 2017-10-30 | Utilize sewage treatment system of LNG cold energy |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107902824A true CN107902824A (en) | 2018-04-13 |
| CN107902824B CN107902824B (en) | 2020-06-02 |
Family
ID=61842374
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711036630.4A Active CN107902824B (en) | 2017-10-30 | 2017-10-30 | Utilize sewage treatment system of LNG cold energy |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107902824B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112575186A (en) * | 2020-12-14 | 2021-03-30 | 江苏卓博环保科技有限公司 | Resourceful treatment device and method for raffinate from vanadium extraction from stone coal |
| CN113200578A (en) * | 2021-04-15 | 2021-08-03 | 内蒙古农业大学 | Method for removing lake pollutants in cold and arid regions by utilizing natural cold energy |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104258593A (en) * | 2014-09-11 | 2015-01-07 | 青岛利和萃取科技有限公司 | Supercritical fluid extraction equipment |
| CN104891593A (en) * | 2015-06-08 | 2015-09-09 | 中石化天津液化天然气有限责任公司 | High-desalting-rate seawater desalination method and device based on liquefied natural gas cold energy |
| CN105605602A (en) * | 2016-01-28 | 2016-05-25 | 华中科技大学 | Natural gas oxygen-enriched combustion system capable of using liquefied natural gas (LNG) cold energy for air separation oxygen-making and carbon capture |
-
2017
- 2017-10-30 CN CN201711036630.4A patent/CN107902824B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104258593A (en) * | 2014-09-11 | 2015-01-07 | 青岛利和萃取科技有限公司 | Supercritical fluid extraction equipment |
| CN104891593A (en) * | 2015-06-08 | 2015-09-09 | 中石化天津液化天然气有限责任公司 | High-desalting-rate seawater desalination method and device based on liquefied natural gas cold energy |
| CN105605602A (en) * | 2016-01-28 | 2016-05-25 | 华中科技大学 | Natural gas oxygen-enriched combustion system capable of using liquefied natural gas (LNG) cold energy for air separation oxygen-making and carbon capture |
Non-Patent Citations (1)
| Title |
|---|
| 韩桂芬等: "CCUS技术路线及发展前景探讨", 《电力科技与环保》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112575186A (en) * | 2020-12-14 | 2021-03-30 | 江苏卓博环保科技有限公司 | Resourceful treatment device and method for raffinate from vanadium extraction from stone coal |
| CN113200578A (en) * | 2021-04-15 | 2021-08-03 | 内蒙古农业大学 | Method for removing lake pollutants in cold and arid regions by utilizing natural cold energy |
| CN113200578B (en) * | 2021-04-15 | 2022-10-14 | 内蒙古农业大学 | Method for removing lake pollutants in cold and arid regions by utilizing natural cold energy |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107902824B (en) | 2020-06-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| AU2007215134B2 (en) | A method for producing a distillate stream from a water stream containing at least one dissolved solid | |
| CN100455520C (en) | Coupling devices of using nuclear energy for sea water desalination, and method | |
| CN105783424B (en) | The air separating method of high-pressure oxygen-enriched gas is produced using cold energy of liquefied natural gas | |
| CN108138595A (en) | Gas processing plant waste heat based on improved Gauss watt meter Xun Huan to electric power and cooling conversion | |
| CN108138599A (en) | Gas processing plant waste heat based on kalina cycle to electric power conversion | |
| US20190039916A1 (en) | A system for flue-gas hydrate-based desalination using lng cold energy | |
| CN104891593B (en) | A kind of equipment with high desalinization method for desalting seawater based on cold energy of liquefied natural gas and device | |
| CN102642975B (en) | Flash evaporation and freezing united seawater desalination system for thermal power plant | |
| CN102320674A (en) | Marine cold and heat cogeneration seawater desalting method and equipment | |
| CN103075250A (en) | Method for generating by graded use of cold energy of liquefied natural gas | |
| CN101871705A (en) | Cooler-heat pump | |
| CN103613153A (en) | Nuclear power and low temperature multi-effect sea water desalination coupling cogeneration system | |
| CN105115245A (en) | System device for trapping liquefied carbon dioxide by using cold energy of liquefied natural gas and method of device | |
| US20080017498A1 (en) | Seawater Desalination Plant | |
| CN107144145B (en) | Trapping magnesite melting fume afterheat and CO are recycled using LNG cold energy2System and method | |
| CN1207726C (en) | Heat storage load normalizing power generation system and generation method for said system | |
| CN107902824A (en) | A kind of sewage disposal system using LNG cold energy | |
| CN209835696U (en) | System for utilize solar photothermal technology to handle coal fired power plant desulfurization waste water | |
| CN102285702B (en) | Device for seawater desalination by recovering waste heat from diesel engine with series-connected heat pipe heat exchangers | |
| CN106830136B (en) | Seawater desalination system based on vortex tube refrigeration | |
| CN110697821B (en) | Seawater source trans-critical carbon dioxide heat pump circulation multi-effect seawater desalination system | |
| JP6089251B2 (en) | How to use hot wastewater and hot waste heat from thermal power plants | |
| CN107138025A (en) | The low-temp methanol washing process that a kind of pressure energy and cold energy high efficiente callback are utilized | |
| CN114890491B (en) | System for seawater desalination | |
| CN208090314U (en) | A kind of natural gas pressure regulating door station pressure energy recycles utilization system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |