CN206089609U - Use marsh gas purification and natural pond liquid processing system of natural pond liquid as CO2 absorbent - Google Patents

Abstract

The utility model relates to an use marsh gas purification and natural pond liquid processing system of natural pond liquid as CO2 absorbent, it includes natural pond liquid filtration equipment, the natural pond liquid CO2 regeneration facility that reduces pressure, indirect heating equipment, poor CO2 natural pond liquid cooling arrangement, natural pond liquid CO2 absorption equipment, washing deamination equipment, marsh gas gas storage equipment, natural pond liquid nitrogen and phosphorus desorption equipment, aqueous ammonia condensation device, aqueous ammonia collecting device, natural pond liquid precipitation apparatus, marsh gas secondary purification equipment, natural pond liquid storage facilities, biogas storage device and CO2 gas collection equipment. The utility model discloses regard as single CO2 absorbent with the produced low -cost natural pond liquid of organic matter anaerobic fermentation, can be under the condition of not adding any external source absorbent, rely on a lot of " CO2 regenerates and absorbs to CO2 " the cyclic process of natural pond liquid completely, realize the purification of whole marsh gas that biogas engineering is produced, finally obtain the biogas of high CH4 content, can effectively reduce the cost that marsh gas CO2 separates.

Description

With biogas slurry as the methane purification of CO2 absorbents and biogas slurry treatment system

Technical field

The utility model is related to CH in biogas₄Enrichment and biogas slurry harmless treatment integrated technique field, and in particular to one Plant the methane purification and biogas slurry treatment system with biogas slurry as CO2 absorbents.

Background technology

Biogas as a kind of regenerative resource in the more ripe application of China, big-and-middle-sized and super-huge biogas engineering Quantity increasingly increases.But because biogas calorific value is relatively low, current biogas primary limitation is used in biogas engineering periphery, seldom can realize High-valued and industrialization is utilized.The main component of biogas is CH₄(60～70%), CO₂(30～40%) and micro H₂S(0.005 0.1%)～the impurity such as, if by CH in biogas₄Content is lifted to natural gas rank (being more than 95%), obtains reproducible biology Natural gas or biological methane, will be provided with substituting the potentiality of fossil natural gas, can not only to a certain extent alleviate natural gas supply Not enough contradiction, moreover it is possible to CO is realized during using energy source₂Near-zero release.Obviously, methane purification prepares bio-natural gas It is to realize biogas is high-valued and industrialization is utilized important channel and direction.Methane purification prepares it is critical only that for bio-natural gas CO in biogas₂High efficiency, low cost removing.At present, CO in biogas₂Isolation technics mainly has high-pressure washing method, pressure swing adsorption method, change Absorption process and membrane separation process etc. are learned, wherein chemical absorption method is biogas CO₂Develop more ripe one kind in isolation technics, with CO₂ Separative efficiency, low CH₄Loss, high CH₄Purity and the advantage such as easy to operate, but the conventional alcamines such as its monoethanolamine for mainly adopting Absorbent richness CO₂The regenerated heat energy consumption of solution is huge, can account for more than the 60% of whole technique total energy consumption, causes CO₂Separation costs Height, causes bio-natural gas with high costs.Therefore, richness CO in chemical absorption method is reduced₂The regeneration energy consumption of absorbent solution is drop Low level bog gas CO₂The key of separation costs.Abandon CO₂Energy consumption highest absorbent richness CO in chemical absorbing₂Solution regenerator section, only adopts Use single CO₂Absorption technique, is to reduce one of most effective mode of chemical absorption method cost for purification, but it is critical only that how to select Suitable absorbent.Such as typical process is, with ammoniacal liquor as absorbent, to absorb CO₂While generate ammonium hydrogen carbonate accessory substance, but This technique consumes huge to ammoniacal liquor, therefore can only be adapted to middle and small scale CO₂Separate situation.

Biogas slurry as biogas engineering accessory substance, with yield it is huge, cheap, rich in beneficiating ingredient for stimulating plant growth etc. Feature, and in alkalescent, possess certain CO₂Absorb potentiality.If can be using biogas engineering biogas slurry produced daily as suction Receive agent and absorb CO in biogas₂, the biogas produced by the same day is processed, while the rich CO that will be generated₂Biogas slurry carries out using in farmland, so as to Realization completes its purification for producing biogas using the biogas slurry produced by biogas engineering completely, abandons to external source chemical absorbent Rely on, in theory can effectively solving tradition CO₂The high problem of chemical absorption process regeneration energy consumption, can also solve typical single CO₂ The big problem of absorbent consumption in absorption technique.Meanwhile, although biogas slurry can be used as a kind of fertilizer, its ammonia nitrogen, total phosphorus, change Learn the indexs such as oxygen demand (COD) and exceed well over discharge and administration standard, without the biogas slurry discharge for processing air pollution and water can be caused Body eutrophication etc., larger harm is caused to environment.And China's biogas slurry annual production is huge, resource utilization rate also less than 20%, Superfluous biogas slurry treatment becomes the Another reason of restriction biogas engineering development.Accordingly, it would be desirable to by biogas higher value application and natural pond Liquid pollution-free process combines, and is carrying out biogas CO₂Isolated high concentration CH₄While, effectively reduce nitrogen in biogas slurry The content of phosphorus and COD etc., makes biogas slurry directly reach administration standard, reduces the farmland area needed for biogas slurry is dissolved.

Utility model content

The purpose of this utility model is to provide a kind of methane purification with biogas slurry as CO2 absorbents and biogas slurry treatment system System, the system carries out decompression regeneration to the former biogas slurry that biogas engineering is produced first, isolates the primary CO in former biogas slurry₂, recover The CO of biogas slurry₂Re-absorption ability.Then using this biogas slurry to CO in biogas₂Separated, and by biogas slurry " CO₂Regenerate CO₂ The multiple circulation of absorption " is to CO in biogas₂Separated, and according to ammonia-nitrogen content difference in former biogas slurry regulating and controlling cycle-index, Can be by CH in biogas through less cycle-index₄Content brings up to Natural gas standard.Meanwhile, biogas slurry CO₂Obtain after regeneration The CO of ppm level concentration₂Gas can be used as greenhouse CO₂Gas fertilizer is applied.Complete biogas CO₂Biogas slurry after separation discharges biogas slurry CO₂Absorb System, by adding cheap CaO and being operated under condition of negative pressure, realizes the removing of nitrogen phosphorus and COD (Chemical in biogas slurry Oxygen Demand, COD) reduce, make biogas slurry after process reach administration standard, agricultural can be used for directly as fertilizer Apply.Meanwhile, the ammonia nitrogen of biogas slurry removing will be reclaimed in ammoniacal liquor form, be used by oneself or be sold.Can be in natural pond by the utility model Itself biogas slurry produced daily is fully relied in gas engineering and realizes biogas CO₂Separate, make CH₄Content is enriched to natural gas rank, Simultaneously the low nitrogen phosphorus and COD content biogas slurries that can directly apply can also be obtained, so as to reach biogas higher value application and biogas slurry treatment Double goal.

To solve above-mentioned technical problem, one kind is with biogas slurry as CO disclosed in the utility model₂The methane purification of absorbent with Biogas slurry treatment system, it is characterised in that：It includes biogas slurry filter plant, biogas slurry CO₂Decompression generating apparatus, heat-exchange apparatus, lean again CO₂Biogas slurry cooling device, biogas slurry CO₂Absorption equipment, washing deamination equipment, biogas storage equipment, biogas slurry nitrogen and phosphorus removing equipment, Ammoniacal liquor condensing plant, ammoniacal liquor collecting device, biogas slurry settling apparatus, biogas secondary purification equipment, biogas slurry storage facilities, biology are natural Gas storage device and CO₂Gas collection equipment, wherein, biogas slurry outlet connection biogas slurry CO of biogas slurry filter plant₂The natural pond of decompression generating apparatus again Liquid entrance, biogas slurry CO₂The lean CO of decompression generating apparatus again₂The lean CO of high temperature of biogas slurry outlet connection heat-exchange apparatus₂Biogas slurry entrance, heat The lean CO of low temperature of switching equipment₂The lean CO of biogas slurry outlet connection₂The low temperature biogas slurry entrance of biogas slurry cooling device, lean CO₂Biogas slurry cooling sets The lean CO of standby normal temperature₂Biogas slurry outlet connection biogas slurry CO₂The lean CO of normal temperature of absorption equipment₂Biogas slurry entrance, biogas slurry CO₂Absorption equipment First richness CO₂Biogas slurry outlet connects the normal temperature richness CO of heat-exchange apparatus by the first delivery pump₂Biogas slurry entrance, heat-exchange apparatus Rich, high temperature CO₂Biogas slurry outlet connection biogas slurry CO₂Rich, high temperature CO of decompression generating apparatus again₂Biogas slurry entrance, biogas slurry CO₂Decompression regeneration sets Standby CO₂The CO of outlet connection washing deamination equipment₂Gas access, washes the CO of deamination equipment₂Gas vent connects CO₂Gas collection The CO of equipment₂Gas input port, washes the ammonia inlet of the ammoniacal liquor outlet connection ammoniacal liquor collecting device of deamination equipment, washes deamination Equipment also has water inlet；

The methane outlet of gas storage equipment first of biogas storage equipment connects biogas slurry CO by the second delivery pump₂Absorption equipment Absorption equipment biogas entrance, biogas slurry CO₂The absorption equipment methane outlet of absorption equipment connects the gas storage equipment of biogas storage equipment Biogas entrance, the methane outlet of gas storage equipment second of biogas storage equipment connects biogas secondary purification equipment by the 3rd delivery pump Secondary purification equipment biogas entrance；

Biogas slurry CO₂Second richness CO of absorption equipment₂Biogas slurry outlet connects biogas slurry nitrogen by the 4th delivery pump and phosphorus removes equipment Biogas slurry entrance, biogas slurry nitrogen and phosphorus removing equipment vavuum pump gas vent connect ammoniacal liquor condensing plant ammonia entrance, natural pond Liquid nitrogen and phosphorus removing equipment also have CaO powder entrance, the ammonia of the ammoniacal liquor outlet connection ammoniacal liquor collecting device of ammoniacal liquor condensing plant Water inlet；The muddy biogas slurry entrance of the biogas slurry outlet connection biogas slurry settling apparatus of biogas slurry nitrogen and phosphorus removing equipment, biogas slurry precipitation sets Standby clarification biogas slurry outlet connects the biogas slurry input port of biogas secondary purification equipment by the 5th delivery pump, and biogas secondary purification sets Standby biogas slurry delivery outlet connects the biogas slurry inlet port of biogas slurry storage facilities, and the bio-natural gas outlet of biogas secondary purification equipment connects Deliver a child the bio-natural gas entrance of thing natural gas storage equipment.

The beneficial effects of the utility model are：

1st, the inexpensive biogas slurry produced by the utility model using organic matter anaerobic fermentation is used as single CO₂Absorbent, can be In the case of without any external source absorbent, the multiple " CO of biogas slurry is completely dependent on₂Regenerate CO₂Absorb " cyclic process, realize Biogas engineering produces the purification of whole biogas, finally gives high CH₄The bio-natural gas of content, can effectively reduce biogas CO₂Separate Cost.

2nd, the utility model is by the cheap CaO powder of addition and changes operating parameter, realizes nitrogen in biogas slurry, phosphorus, chemistry The efficient removal of oxygen demand, substantially reduces plant physiology toxicity when biogas slurry is finally applied, and improves the recycling of biogas slurry Degree, reduces the farmland area needed for biogas slurry of dissolving.

3rd, CO of the utility model to produce in system₂Gas fertilizer and richness CO₂Biogas slurry is CO₂Carrier, from gas phase and the side of liquid phase two Face provides growth necessary CO for farm-forestry crop and plant growth₂, the yield of farm-forestry crop and plant can be effectively improved, while Strengthen it to CO₂Fixation, contribute to reduce greenhouse effects.

Description of the drawings

Fig. 1 is structured flowchart of the present utility model；

Fig. 2 is CH after biogas primary purification₄Changes of contents figure；

Fig. 3 is CO after 1000mg/L and 2000mg/L ammonia nitrogens biogas slurry is repeatedly purified₂Uptake variation diagram；

Fig. 4 is total phosphorus content figure after nitrogen and phosphorus removing；

Fig. 5 is ammonia-nitrogen content figure after nitrogen and phosphorus removing；

Fig. 6 is that COD contains spirogram after nitrogen and phosphorus removing.

In Fig. 2, biogas slurry CO₂Regeneration pressure be 40KPa, 77 DEG C of temperature, the time is 30min；CO₂It is 25 DEG C to absorb temperature, is inhaled It is 25min between the time receiving；In Fig. 3, CO₂It is 25 DEG C to absorb temperature, and the time is 25min；In Fig. 4, CaO additions are 10g/L, are run Pressure is 40KPa, and temperature is 77 DEG C, and the time is 30min；In Fig. 5, CaO additions are 10g/L, and operation pressure is 40KPa, warm Spend for 77 DEG C；In Fig. 6, CaO additions are 10g/L, and operation pressure is 40KPa, and temperature is 77 DEG C, and the time is 30min.

Wherein, 1-biogas slurry filter plant, 1.1-fresh biogas slurry entrance, the outlet of 1.2-biogas slurry, 2-biogas slurry CO₂Decompression is again Generating apparatus, 2.1-biogas slurry entrance, 2.2-lean CO₂Biogas slurry outlet, 2.3-rich, high temperature CO₂Biogas slurry entrance, 2.4-CO₂Outlet, The lean CO of 3-heat-exchange apparatus, 3.1-high temperature₂The lean CO of biogas slurry entrance, 3.2-low temperature₂Biogas slurry outlet, 3.3-normal temperature richness CO₂Biogas slurry Entrance, 3.4-rich, high temperature CO₂Biogas slurry outlet, 4-lean CO₂Biogas slurry cooling device, 4.1-low temperature biogas slurry entrance, 4.2-normal temperature are lean CO₂Biogas slurry outlet, 5-biogas slurry CO₂The lean CO of absorption equipment, 5.1-normal temperature₂Biogas slurry entrance, the 5.2-the first richness CO₂Biogas slurry outlet, 5.3-absorption equipment biogas entrance, 5.4-absorption equipment methane outlet, the 5.5-the second richness CO₂It is biogas slurry outlet, 6-the first defeated Send pump, 7-washing deamination equipment, 7.1-CO₂Gas access, 7.2-CO₂Gas vent, 7.3-water inlet, 7.4-ammoniacal liquor goes out Mouth, 8-biogas storage equipment, the methane outlet of 8.1-gas storage equipment first, 8.2-gas storage equipment biogas entrance, 8.3-gas storage The methane outlet of equipment second, 9-biogas slurry nitrogen and phosphorus removing equipment, 9.1-biogas slurry entrance, the outlet of 9.2-biogas slurry, 9.3-CaO powder The last entrance, 9.4-biogas slurry nitrogen and phosphorus removing vavuum pump of equipment, 10-ammoniacal liquor condensing plant, 10.1-ammonia entrance, 10.2- Ammoniacal liquor outlet, 11-ammoniacal liquor collecting device, 11.1-ammonia inlet, the 12-the four delivery pump, 13-biogas slurry settling apparatus, 13.1-muddy biogas slurry entrance, 13.2-clarification biogas slurry outlet, the 14-the five delivery pump, 15-biogas secondary purification equipment, 15.1-biogas slurry input port, 15.2-biogas slurry delivery outlet, 15.3-secondary purification equipment biogas entrance, 15.4-bio-natural gas Outlet, 16-biogas slurry storage facilities, 16.1-biogas slurry inlet port, 17-bio-natural gas storage device, 17.1-biology are natural Gas entrance, 18-CO₂Gas collection equipment, 18.1-CO₂Gas input port, the 19-the second delivery pump, the 20-the three delivery pump, 21.1-first flowmeter, 21.2-second flowmeter, the 21.3-the three flowmeter, the 21.4-the four flowmeter, 21.5-the Five flowmeters, the 21.6-the six flowmeter, 22.1-first pressure sensor, 22.2-second pressure sensor, 23.1-the One temperature sensor, 23.2-second temperature sensor, 24-mass sensor, 25-pH sensors, the 26.1-the one CH₄It is dense Degree sensor, the 26.2-the two CH₄Concentration sensor.

Specific embodiment

Below in conjunction with the drawings and specific embodiments, the utility model is described in further detail：

One kind of the present utility model is with biogas slurry as CO₂The methane purification of absorbent and biogas slurry treatment system, as described in Figure 1, It includes biogas slurry filter plant 1, biogas slurry CO₂Decompression regeneration equipment 2, heat-exchange apparatus 3, lean CO₂Biogas slurry cooling device 4, biogas slurry CO₂Absorption equipment 5, washing deamination equipment 7, biogas storage equipment 8, biogas slurry nitrogen and phosphorus removing equipment 9, ammoniacal liquor condensing plant 10, Ammoniacal liquor collecting device 11, biogas slurry settling apparatus 13, biogas secondary purification equipment 15, biogas slurry storage facilities 16, bio-natural gas are deposited Storage equipment 17 and CO₂Gas collection equipment 18, wherein, the biogas slurry outlet 1.2 of biogas slurry filter plant 1 connects biogas slurry CO₂Reduce pressure generating apparatus again 2 biogas slurry entrance 2.1, biogas slurry CO₂The lean CO of decompression regeneration equipment 2₂The high temperature that biogas slurry outlet 2.2 connects heat-exchange apparatus 3 is lean CO₂Biogas slurry entrance 3.1, the lean CO of low temperature of heat-exchange apparatus 3₂The lean CO of the connection of biogas slurry outlet 3.2₂The low temperature natural pond of biogas slurry cooling device 4 Liquid entrance 4.1, lean CO₂The lean CO of normal temperature of biogas slurry cooling device 4₂Biogas slurry outlet 4.2 connects biogas slurry CO₂The normal temperature of absorption equipment 5 is lean CO₂Biogas slurry entrance 5.1, biogas slurry CO₂First richness CO of absorption equipment 5₂Biogas slurry outlet 5.2 connects heat exchange by the first delivery pump 6 The normal temperature richness CO of equipment 3₂Biogas slurry entrance 3.3, rich, high temperature CO of heat-exchange apparatus 3₂Biogas slurry outlet 3.4 connects biogas slurry CO₂Decompression is again Rich, high temperature CO of generating apparatus 2₂Biogas slurry entrance 2.3, biogas slurry CO₂The CO of decompression regeneration equipment 2₂The connection washing deamination equipment of outlet 2.4 7 CO₂Gas access 7.1, washes the CO of deamination equipment 7₂Gas vent 7.2 connects CO₂The CO of gas collection equipment 18₂Gas is input into Mouth 18.1, the ammoniacal liquor outlet 7.4 for washing deamination equipment 7 connects the ammonia inlets 11.1 of ammoniacal liquor collecting devices 11, and washing deamination sets Standby 7 also have water inlet 7.3；

First methane outlet of gas storage equipment 8.1 of biogas storage equipment 8 connects biogas slurry CO by the second delivery pump 19₂Absorb The absorption equipment biogas entrance 5.3 of equipment 5, biogas slurry CO₂The connection biogas storage of absorption equipment methane outlet 5.4 of absorption equipment 5 The gas storage equipment biogas entrance 8.2 of equipment 8, second methane outlet of gas storage equipment 8.3 of biogas storage equipment 8 is by the 3rd conveying The secondary purification equipment biogas entrance 15.3 of the connection biogas secondary purification of pump 20 equipment 15；

Biogas slurry CO₂Second richness CO of absorption equipment 5₂Biogas slurry outlet 5.5 connects biogas slurry nitrogen by the 4th delivery pump 12 and phosphorus is de- Except the gas vent connection ammoniacal liquor condensing plant of the vavuum pump 9.4 of the biogas slurry entrance 9.1 of equipment 9, biogas slurry nitrogen and phosphorus removing equipment 9 10 ammonia entrance 10.1, biogas slurry nitrogen and phosphorus removing equipment 9 also have CaO powder entrance 9.3, the ammoniacal liquor of ammoniacal liquor condensing plant 10 Outlet 10.2 connects the ammonia inlet 11.1 of ammoniacal liquor collecting device 11；The biogas slurry outlet 9.2 of biogas slurry nitrogen and phosphorus removing equipment 9 connects The muddy biogas slurry entrance 13.1 of biogas slurry settling apparatus 13, the clarification biogas slurry outlet 13.2 of biogas slurry settling apparatus 13 is by the 5th conveying The biogas slurry input port 15.1 of the connection biogas secondary purification of pump 14 equipment 15, the biogas slurry delivery outlet 15.2 of biogas secondary purification equipment 15 The biogas slurry inlet port 16.1 of connection biogas slurry storage facilities 16, the bio-natural gas outlet 15.4 of biogas secondary purification equipment 15 connects The bio-natural gas entrance 17.1 of bio-natural gas storage device 17.

In above-mentioned technical proposal, biogas slurry outlet 1.2 and biogas slurry CO of the biogas slurry filter plant 1₂Decompression regeneration equipment 2 First flowmeter 21.1, biogas slurry CO are provided with the connecting line of biogas slurry entrance 2.1₂The lean CO of decompression regeneration equipment 2₂Biogas slurry is exported 2.2 and the lean CO of high temperature of heat-exchange apparatus 3₂Second flowmeter 21.2, biogas slurry CO are provided with pipeline between biogas slurry entrance 3.1₂Inhale First richness CO of receiving unit 5₂Biogas slurry outlet 5.2 and the normal temperature richness CO of heat-exchange apparatus 3₂Set in pipeline between biogas slurry entrance 3.3 There are the 3rd flowmeter 21.3, the second methane outlet of gas storage equipment 8.3 and the biogas secondary purification equipment 15 of biogas storage equipment 8 The 4th flowmeter 21.4, biogas slurry CO are provided with pipeline between secondary purification equipment biogas entrance 15.3₂The second of absorption equipment 5 Rich CO₂The 5th flowmeter is provided with pipeline between the biogas slurry entrance 9.1 of biogas slurry outlet 5.5 and biogas slurry nitrogen and phosphorus removing equipment 9 21.5, between the clarification biogas slurry outlet 13.2 of biogas slurry settling apparatus 13 and the biogas slurry input port 15.1 of biogas secondary purification equipment 15 Pipeline in be provided with the 6th flowmeter 21.6.

In above-mentioned technical proposal, in the biogas storage equipment 8 CH is provided with₄Concentration sensor 26.1, biogas is secondary Between the bio-natural gas outlet 15.4 of equipment for purifying 15 and the bio-natural gas entrance 17.1 of bio-natural gas storage device 17 Pipeline in be provided with the 2nd CH₄Concentration sensor 26.2.

In above-mentioned technical proposal, the CaO powder entrance 9.3 of the biogas slurry nitrogen and phosphorus removing equipment 9 is provided with mass sensor 24。

In above-mentioned technical proposal, biogas slurry CO₂First pressure sensor 22.1 and first is provided with decompression regeneration equipment 2 Second pressure sensor 22.2 and second temperature sensing are provided with temperature sensor 23.1, the biogas slurry nitrogen and phosphorus removing equipment 9 Device 23.2.

In above-mentioned technical proposal, in the biogas slurry storage facilities 16 pH sensors 25 are provided with.

In above-mentioned technical proposal, mass sensor 24, pH sensors 25, each temperature sensor, each pressure sensor, Each CH₄Concentration sensor and each flowmeter are used to measure the relevant parameter of solution everywhere or gas, determine that the system is It is no to have deficiency or more than relevant parameter in the operation of normal scope, will be to biogas slurry flow, CaO powder quality or heater temperature Degree and equipment pressure etc. are adjusted, it is ensured that the normal work of system.

In above-mentioned technical proposal, the secondary purification equipment biogas entrance 15.3 is located under biogas secondary purification equipment 15 End, biogas slurry input port 15.1 is located at the upper end of biogas secondary purification equipment 15.

A kind of methane purification of said system and biogas slurry treatment method, the former biogas slurry that the method is produced to biogas engineering is first The primary CO in former biogas slurry is regenerated by pressure reducing mode₂, recover the CO of biogas slurry₂Re-absorption ability.Then using this biogas slurry to natural pond CO in gas₂Separated, and by biogas slurry " CO₂Regeneration-CO₂Repeatedly circulation carries out CO to biogas for absorption "₂Separate, and according to original Ammonia-nitrogen content difference, can be by CH in biogas through less circulation regulating and controlling cycle-index in biogas slurry₄Content brings up to natural Gas standard.Meanwhile, biogas slurry CO₂The CO of the ppm level concentration obtained after regeneration₂Gas can be applied as greenhouse gas fertilizer.Complete biogas CO₂Biogas slurry after separation removes ammonia nitrogen, total phosphorus and the drop of wherein most by the cheap CaO of addition and under the conditions of negative-pressure operation Low COD, makes biogas slurry after process reach administration standard, can be used for agricultural application directly as fertilizer.Meanwhile, the ammonia nitrogen of biogas slurry removing To reclaim in ammoniacal liquor form, and be used by oneself or sold.Itself can be fully relied in biogas engineering by the utility model daily Produced biogas slurry realizes biogas CO₂Separate, make CH₄Content is enriched to natural gas rank, while can also obtain what is can directly applied Low nitrogen phosphorus and COD concentration biogas slurries, so as to reach the double goal of biogas higher value application and biogas slurry treatment；

The utility model specifically comprises the steps：

Step 1：The fresh biogas slurry that biogas engineering Zymolysis Equipment is produced is filtered into biogas slurry by fresh biogas slurry entrance 1.1 and set Standby 1, then after biogas slurry filter plant 1 is filtered, biogas slurry CO is entered by biogas slurry entrance 2.1₂(biogas slurry is entered decompression regeneration equipment 2 Volume according to specific biogas engineering scale depending on, with volume yield rate as 1, hydraulic retention times are for the biogas engineering of 20d Example, it is used for biogas CO₂Detached biogas slurry is about 1 with biogas volume ratio：20), in biogas slurry CO₂In decompression regeneration equipment 2 biogas slurry with The rotating speed of 500～1000r/min is stirred by consistent, meanwhile, biogas slurry CO₂The vavuum pump that decompression regeneration equipment 2 is carried is provided The absolute pressure condition of 39～41kPa (preferred 40kPa), biogas slurry CO₂The heater that decompression regeneration equipment 2 is carried provides biogas slurry The condition of 76～78 DEG C of temperature (preferably 77 DEG C), under this operating parameter, biogas slurry CO₂Decompression regeneration equipment 2 runs 25～30min (preferred 25min), biogas slurry CO₂Decompression regeneration equipment 2 is by lean CO₂Biogas slurry passes through the lean CO of high temperature₂Biogas slurry entrance 3.1 enters heat exchange Equipment 3, completes to enter lean CO after heat exchange₂Biogas slurry cooling device 4, in lean CO₂Biogas slurry is cooled to into 15 in biogas slurry cooling device 4～ After 30 DEG C (20 DEG C of preferred normal temperature), by the lean CO of normal temperature₂Biogas slurry entrance 5.1 enters natural pond biogas slurry CO₂Absorption equipment 5；

Step 2：Biogas slurry CO₂The CO that the gas vent of the vavuum pump that decompression regeneration equipment 2 is carried is discharged₂, ammonia and volatility The mixed gas of aliphatic acid pass through CO₂Gas access 7.1 enters washing deamination equipment 7, and clear water enters water elution from water inlet 7.3 Ammonia equipment 7, the impurity (ammonia in mixed gas in washing deamination equipment 7 using water elution except ammonia and volatile fatty acid Gas and volatile fatty acid etc.), the CO washed in deamination equipment 7₂Gas passes through CO₂Gas vent 7.2 enters CO₂Gas collection equipment 18 store for future use, and from the ammoniacal liquor out of washing deamination equipment 7 ammoniacal liquor collecting device 11 is entered；

Step 3：Biogas in biogas storage equipment 8 is by the first methane outlet of gas storage equipment 8.1 by the second delivery pump 19 It is passed through biogas slurry CO₂Absorption equipment 5, carries out at normal temperatures biogas slurry CO₂Absorb, separate CO₂Biogas Jing gas storage equipment biogas entrances afterwards 8.2 return in biogas storage equipment 8, and the biogas in biogas storage equipment 8 persistently carries out CO₂The detached time is 20～30min (preferably 25min), by the CH in biogas storage equipment 8₄Natural pond in the monitoring biogas storage of concentration sensor 26.1 equipment 8 Gas CH₄Change in concentration, is judged in biogas slurry CO with this₂The CO of biogas slurry in absorption equipment 5₂Saturation terminal is absorbed, when biogas storage equipment Biogas CH in 8₄When concentration stablizes constant, biogas slurry CO out of service₂Absorption equipment 5；

Step 4：When step 3 is completed, biogas slurry CO is made₂Rich CO in absorption equipment 5₂Biogas slurry passes through the first delivery pump 6 again It is passed through biogas slurry CO₂Decompression regeneration equipment 2, and control rich CO by the 3rd flowmeter 21.3₂Biogas slurry is passed through completely biogas slurry CO₂Decompression Regeneration equipment 2, repeats biogas slurry CO of step 1₂Decompression regenerative process, through step 1 and biogas slurry CO of step 3₂Regenerate suction The multiple circulation received is realized to CH in biogas storage equipment 8₄Continuous enrichment, now complete biogas first time purification (circulation Number of times is depending on CH in ammonia-nitrogen content, biogas in biogas slurry₄Content and target organism natural gas CH₄The demand of content)；

Step 5：Through multiple CO₂The cyclic process for absorbing is regenerated, is completed to biogas CO₂After separation, rich CO is made₂Biogas slurry Jing biogas slurries CO₂Second richness CO of absorption equipment 5₂Biogas slurry outlet 5.5 enters biogas slurry nitrogen by the 4th delivery pump 12 and phosphorus removes equipment 9, CaO powder Jing CaO powders entrance 9.3 enters biogas slurry nitrogen and phosphorus removing equipment 9, the CaO for controlling to add by mass sensor 24 The mass concentration of powder is 5～10g/L (preferably 5g/L), in biogas slurry nitrogen and phosphorus removing equipment 9, adds the biogas slurry of CaO powder Stirred by consistent with the rotating speed of 500～1000r/min (preferably 500r/min), meanwhile, biogas slurry nitrogen and phosphorus remove equipment 9 Vavuum pump 9.4 the absolute pressure condition of 39～41kPa (preferably 40kPa) is provided, biogas slurry nitrogen and phosphorus removing equipment 9 are carried Heater provides the condition of biogas slurry temperature 76～78 DEG C (preferably 77 DEG C), and under this operating parameter, biogas slurry nitrogen and phosphorus are removed Equipment 9 runs 30～50min (preferably 40min), and produced gas (predominantly ammonia and vapor) passes through natural pond in operation The vavuum pump 9.4 of liquid nitrogen and phosphorus removing equipment 9 is transported to ammoniacal liquor condensing plant 10 and is condensed, and by with ammoniacal liquor condensing plant 10 The ammoniacal liquor collecting device 11 of connection is collected；

Step 6：Suspended biogas slurry is transported to biogas slurry settling apparatus 13 by biogas slurry nitrogen and phosphorus removing equipment 9 carries out precipitation point From, biogas slurry is in clear state, and now biogas slurry pH is 11～12 (preferably 12), and rich in Ca²⁺Ion；

Step 7：The biogas slurry of clear state is delivered to into the biogas slurry of biogas secondary purification equipment 15 by the 5th delivery pump 14 Input port 15.1 sprays, in addition, making the biogas that purification for the first time is completed in biogas storage equipment 8 from biogas secondary purification equipment 15 Secondary purification equipment biogas entrance 15.3 enter, biogas is fully contacted in the biogas storage equipment 8 with biogas slurry, realizes secondary carrying It is pure, the biogas after secondary purification is completed into bio-natural gas storage device 17, and by bio-natural gas storage device 17 The 2nd CH₄Concentration sensor 26.2 monitors the CH of bio-natural gas₄Content, completes the low nitrogen and phosphorus content of biogas secondary purification Biogas slurry enters biogas slurry storage facilities 16, pours for crops and applies.

In the step of above-mentioned technical proposal 1, biogas slurry CO₂The biogas slurry liquid inlet volume of generating apparatus that reduces pressure again and the biogas for purification Depending on volume ratio is according to the volume yield rate of biogas engineering and the ratio of hydraulic retention times, specially：Biogas volume：Biogas slurry body Product=volume yield rate × hydraulic retention times.

Biogas slurry CO in the step of above-mentioned technical proposal 2₂The CO that the gas vent of the vavuum pump of generating apparatus that reduces pressure again is discharged₂It is dense Spend for ppm levels, can be used as greenhouse CO₂Gas fertilizer.

Biogas slurry CO in the step of above-mentioned technical proposal 3₂Absorbing can adopt bubble absorption, select also dependent on project scale is different Select using equipment such as absorption tower or hollow-fibre membranes.

Biogas slurry " CO in the step of above-mentioned technical proposal 4₂Regenerate CO₂Cycle-index is according to ammonia nitrogen in biogas slurry needed for absorption " Content, biogas CH₄Content and bio-natural gas CH₄The parameters such as content determining, by the bench-scale testing carried out in laboratory, Be respectively 1000 with ammonia-nitrogen content, 2000,3000, the biogas slurry of 4000mg/L is to CH₄Initial content is that 60% biogas carries out this Technique is purified, it is concluded that being：The biogas slurry of ammonia-nitrogen content 1000mg/L biogas CH Jing after 5 cyclic absorptions₄Content reaches 71.1%, but through 5 times circulation after biogas slurry CO₂Absorbent properties decline not substantially, therefore can be by increasing biogas slurry circulation time Count to make CH₄Content reaches 95%；The biogas slurry of ammonia-nitrogen content 2000mg/L biogas CH Jing after 5 cyclic absorptions₄Content reaches 88.6%, same biogas slurry CO₂Absorbent properties decline unobvious, it is also possible to make CH by increasing cycle-index₄Content reaches 95%；The biogas slurry of ammonia-nitrogen content 3000mg/L biogas CH Jing after 5 cyclic absorptions₄Content reaches 96.6%；And ammonia-nitrogen content 3 circulations of biogas slurry Jing of 1000mg/L, you can make the CH of biogas in biogas storage equipment₄Content reaches 95.4%, concrete effect See accompanying drawing 2, ammonia-nitrogen content 1000, the CO of 2000mg/L biogas slurries₂Fig. 3 is shown in absorbent properties change.

In the step of above-mentioned technical proposal 5, the coolant temperature of ammoniacal liquor condensing plant 10 is -10～0 DEG C (preferably -5 ℃)。

In the step of above-mentioned technical proposal 5, CaO powder particle diameter need to be controlled in 0.1～0.5mm, it is therefore an objective to ensure CaO powder In being completely dissolved in biogas slurry, biogas slurry pH value is improved as far as possible, and reduce CaO consumptions.

In above-mentioned technical proposal, the removal efficiency of ammonia nitrogen can reach more than 90% in the step 5, and the removal efficiency of total phosphorus is reachable 55.6% is can reach to 73.7%, COD removal efficiencies, concrete effect is shown in accompanying drawing 4～6.

In the step of above-mentioned technical proposal 6, suspended biogas slurry is transported to biogas slurry precipitation by biogas slurry nitrogen and phosphorus removing equipment (9) Equipment 13 carries out the precipitate and separate of 1～3 hour (preferably 1 hour).

In the step of above-mentioned technical proposal 7, biogas secondary purification equipment adopts packed tower absorption equipment, according to engine request The equipment such as hollow-fibre membrane may also be employed.

In above-mentioned technical proposal, pH must be in 6～8 scopes after carrying out secondary purification to biogas for biogas slurry in the step 7 It is interior to be used for agricultural application, due to biogas slurry ammonia-nitrogen content difference, CO in biogas after primary purification₂Content is different, so may not The pH for completing biogas slurry after secondary purification be can guarantee that in OK range, needs are supervised by the pH sensors 25 in biogas slurry storage facilities 16 Whether the pH of control biogas slurry is in 6～8, if suitably not adjusting its pH value by pH adjustment equipments in the range of suitable administration.

The utility model regenerates at a lower temperature the primary CO of biogas slurry by way of decompression₂, so as to recover biogas slurry CO₂Re-absorption ability, and by biogas slurry " CO₂Regenerate CO₂CO in the multiple multi-cycle separation biogas of absorption "₂.Complete biogas CO₂Inhale Biogas slurry after receipts adds again cheap CaO, at reduced pressure conditions removal of ammonia and nitrogen and phosphorus and reduction COD contents, and will remove in biogas slurry Ammonia nitrogen reclaimed in the form of ammoniacal liquor and sold or used by oneself.Biogas slurry after the removing of nitrogen phosphorus is then directly carried out Jing after pH is stably processed Agricultural application.

The content that this specification is not described in detail belongs to prior art known to professional and technical personnel in the field.

Claims (7)

1. one kind is with biogas slurry as CO₂The methane purification of absorbent and biogas slurry treatment system, it is characterised in that：It is filtered including biogas slurry Equipment (1), biogas slurry CO₂Reduce pressure generating apparatus (2), heat-exchange apparatus (3), lean CO again₂Biogas slurry cooling device (4), biogas slurry CO₂Absorb Equipment (5), washing deamination equipment (7), biogas storage equipment (8), biogas slurry nitrogen and phosphorus removing equipment (9), ammoniacal liquor condensing plant (10), ammoniacal liquor collecting device (11), biogas slurry settling apparatus (13), biogas secondary purification equipment (15), biogas slurry storage facilities (16), Bio-natural gas storage device (17) and CO₂Gas collection equipment (18), wherein, biogas slurry outlet (1.2) of biogas slurry filter plant (1) is even Connect biogas slurry CO₂The biogas slurry entrance (2.1) of decompression generating apparatus (2) again, biogas slurry CO₂The lean CO of decompression generating apparatus (2) again₂Biogas slurry is exported (2.2) the lean CO of high temperature of heat-exchange apparatus (3) is connected₂Biogas slurry entrance (3.1), the lean CO of low temperature of heat-exchange apparatus (3)₂Biogas slurry goes out Mouth (3.2) connects lean CO₂Low temperature biogas slurry entrance (4.1) of biogas slurry cooling device (4), lean CO₂The normal temperature of biogas slurry cooling device (4) Lean CO₂Biogas slurry outlet (4.2) connection biogas slurry CO₂The lean CO of normal temperature of absorption equipment (5)₂Biogas slurry entrance (5.1), biogas slurry CO₂Absorption sets The first richness CO of standby (5)₂Biogas slurry exports the normal temperature richness CO that (5.2) connect heat-exchange apparatus (3) by the first delivery pump (6)₂Biogas slurry Entrance (3.3), rich, high temperature CO of heat-exchange apparatus (3)₂Biogas slurry outlet (3.4) connection biogas slurry CO₂The height of decompression generating apparatus (2) again Warm richness CO₂Biogas slurry entrance (2.3), biogas slurry CO₂The CO of decompression generating apparatus (2) again₂Outlet (2.4) connection washing deamination equipment (7) CO₂Gas access (7.1), washes the CO of deamination equipment (7)₂Gas vent (7.2) connects CO₂The CO of gas collection equipment (18)₂Gas Input port (18.1), washes the ammonia inlet of ammoniacal liquor outlet (7.4) connection ammoniacal liquor collecting device (11) of deamination equipment (7) (11.1), wash deamination equipment (7) and also there is water inlet (7.3)；

The methane outlet of the gas storage equipment first (8.1) of biogas storage equipment (8) connects biogas slurry CO by the second delivery pump (19)₂Inhale Absorption equipment biogas entrance (5.3) of receiving unit (5), biogas slurry CO₂The absorption equipment methane outlet (5.4) of absorption equipment (5) is even Gas storage equipment biogas entrance (8.2) of biogas storage equipment (8) is connect, the biogas of gas storage equipment second of biogas storage equipment (8) goes out Mouth (8.3) passes through the secondary purification equipment biogas entrance that the 3rd delivery pump (20) connects biogas secondary purification equipment (15) (15.3)；

Biogas slurry CO₂Second richness CO of absorption equipment (5)₂Biogas slurry exports (5.5) and connects biogas slurry nitrogen and phosphorus by the 4th delivery pump (12) The gas vent connection ammonia of the vavuum pump (9.4) of the biogas slurry entrance (9.1) of removing equipment (9), biogas slurry nitrogen and phosphorus removing equipment (9) The ammonia entrance (10.1) of water-condensing apparatus (10), biogas slurry nitrogen and phosphorus removing equipment (9) also have CaO powder entrance (9.3), ammonia The ammonia inlet (11.1) of ammoniacal liquor outlet (10.2) connection ammoniacal liquor collecting device (11) of water-condensing apparatus (10)；Biogas slurry nitrogen and phosphorus The muddy biogas slurry entrance (13.1) of biogas slurry outlet (9.2) connection biogas slurry settling apparatus (13) of removing equipment (9), biogas slurry precipitation sets Clarification biogas slurry outlet (13.2) of standby (13) is defeated by the biogas slurry that the 5th delivery pump (14) connects biogas secondary purification equipment (15) Entrance (15.1), the biogas slurry of the biogas slurry delivery outlet (15.2) connection biogas slurry storage facilities (16) of biogas secondary purification equipment (15) is entered Entrance (16.1), bio-natural gas outlet (15.4) the connection bio-natural gas storage device of biogas secondary purification equipment (15) (17) bio-natural gas entrance (17.1).

2. according to claim 1 with biogas slurry as CO₂The methane purification of absorbent and biogas slurry treatment system, it is characterised in that： Biogas slurry outlet (1.2) and biogas slurry CO of the biogas slurry filter plant (1)₂The company of the decompression biogas slurry entrance (2.1) of generating apparatus (2) again Adapter is provided with first flowmeter (21.1), biogas slurry CO in road₂The lean CO of decompression generating apparatus (2) again₂Biogas slurry exports (2.2) with heat friendship The lean CO of high temperature of exchange device (3)₂Second flowmeter (21.2), biogas slurry CO are provided with pipeline between biogas slurry entrance (3.1)₂Absorb First richness CO of equipment (5)₂Biogas slurry exports the normal temperature richness CO of (5.2) and heat-exchange apparatus (3)₂Pipe between biogas slurry entrance (3.3) The 3rd flowmeter (21.3) is provided with road, the methane outlet of the gas storage equipment second (8.3) of biogas storage equipment (8) is secondary with biogas The 4th flowmeter (21.4), biogas slurry are provided with pipeline between secondary purification equipment biogas entrance (15.3) of equipment for purifying (15) CO₂Second richness CO of absorption equipment (5)₂Biogas slurry export (5.5) and biogas slurry nitrogen and phosphorus removing equipment (9) biogas slurry entrance (9.1) it Between pipeline in be provided with the 5th flowmeter (21.5), clarification biogas slurry outlet (13.2) of biogas slurry settling apparatus (13) is secondary with biogas The 6th flowmeter (21.6) is provided with pipeline between the biogas slurry input port (15.1) of equipment for purifying (15).

3. according to claim 1 with biogas slurry as CO₂The methane purification of absorbent and biogas slurry treatment system, it is characterised in that： A CH is provided with the biogas storage equipment (8)₄Concentration sensor (26.1), the biological day of biogas secondary purification equipment (15) So it is provided with the pipeline between gas outlet (15.4) and the bio-natural gas entrance (17.1) of bio-natural gas storage device (17) 2nd CH₄Concentration sensor (26.2).

4. according to claim 1 with biogas slurry as CO₂The methane purification of absorbent and biogas slurry treatment system, it is characterised in that： The CaO powder entrance (9.3) of the biogas slurry nitrogen and phosphorus removing equipment (9) is provided with mass sensor (24).

5. according to claim 1 with biogas slurry as CO₂The methane purification of absorbent and biogas slurry treatment system, it is characterised in that： Biogas slurry CO₂The generating apparatus (2) that reduce pressure again are interior to be provided with first pressure sensor (22.1) and the first temperature sensor (23.1), institute State in biogas slurry nitrogen and phosphorus removing equipment (9) and be provided with second pressure sensor (22.2) and second temperature sensor (23.2).

6. according to claim 1 with biogas slurry as CO₂The methane purification of absorbent and biogas slurry treatment system, it is characterised in that： PH sensors (25) are provided with the biogas slurry storage facilities (16).

7. according to claim 1 with biogas slurry as CO₂The methane purification of absorbent and biogas slurry treatment system, it is characterised in that： The secondary purification equipment biogas entrance (15.3) is positioned at biogas secondary purification equipment (15) lower end, biogas slurry input port (15.1) position In biogas secondary purification equipment (15) upper end.