CN106047415A

CN106047415A - Method for preparing high-calorific-value gas through domestic waste oxygen-enriched pressurizing

Info

Publication number: CN106047415A
Application number: CN201610378488.0A
Authority: CN
Inventors: 李海平
Original assignee: Guangxi Gaoyuan Environmental Engineering Co Ltd
Current assignee: Guangxi Gaoyuan Environmental Engineering Co Ltd
Priority date: 2016-06-01
Filing date: 2016-06-01
Publication date: 2016-10-26

Abstract

The invention discloses a method for preparing high-calorific-value gas through domestic waste oxygen-enriched pressurizing. The method is characterized in that a sealed pyrolysis gasifier is used for preparing high-calorific-value gas, domestic waste is added into the sealed pyrolysis gasifier, air with the oxygen-enriched concentration being 50% is pressurized to 2.0-2.5 MPa, then the air is mixed with overheated steam to form a gasification agent, the gasification agent is introduced into a gasifier from a tower type fire grate at the bottom of the pyrolysis gasifier, waste moves downwards, heat moves upwards along with airflow, gasification and pyrolysis reaction of heated waste is promoted, the high temperature of 1200 DEG C is generated, high-calorific-value gas containing 80% of CO, H2, CO2 and CH4 is generated, the waste is finally combusted into ash and discharged from the tower type fire grate at the bottom, and crude combustible gas output from the upper portion of the pyrolysis gasifier is purified, washed and cooled to generate gas products with the heat value being 12 MJ/Nm<3>, so that the targets for harmlessness, reduction and resource utilization of domestic waste are achieved.

Description

The method that high heating value combustion gas is produced in the oxygen-enriched pressurization of house refuse

Technical field

The present invention relates to solid waste pyrolytic gasification technical field, height is produced in the especially oxygen-enriched pressurization of one way of life rubbish The method of calorific value fuel gas.

Background technology

At present, the processing method of rubbish, at China's predominantly landfill, account for 85%；Secondary for compost, account for 10%；Only 3%-5% For burning disposal；Landfill takes up an area big, brings secondary pollution, discharges toxic and harmful, polluted underground water, grows pathogenic bacteria etc., institute With, both at home and abroad many landfill yards have started to again scoop away landfill waste, do not stay future trouble；Compost cost is high, and fertilizer efficiency is low, and product is without city , poor stability；Burn away the refuse at the bottom of temperature, easily produce the extremely toxic substances such as dioxin, cause secondary pollution, and invest huge, Easily in terms of several hundred million；Do not reach the technology requirement of burning electricity generation owing to China's refuse thermal value is low, need to add substantial amounts of auxiliary combustion Material (oil and house refuse), so improves refuse thermal value and carries out generating and lose more than gain, make waste incineration flow process do more complicated and more complicated, Do more expensive and more expensive, and generate electricity and produce little effect, it is difficult to maintain and run；Require that treatment scale is big technically it addition, burn, just can reach To properly functioning, China overwhelming majority small and medium-sized cities daily output of refuse, below 500 tons, uses the garbage incineration technology of several hundred million unit It is that local finance are unaffordable.The existing garbage comprehensive treatment technology released again: first sort, then sorting thing is classified into Row integrated treatment；It has a problem in that the sorting of existing sorting machine is moist and viscous house refuse together is difficult to prove effective, no The purpose of thorough garbage-sorting can be realized, and artificial separation is very big to the hazardness of human body, for producing the quantity of refuse of thousands of tons of daily, Artificial separation operation is also unaffordable, and it is the most tired that China's rubbish present situation to realize in the technology that is sorted on and fund before treatment Difficult, therefore there is expert to propose: employing new technology to sort after processing utilizes the direction being only garbage disposal again.

China's municipal refuse feature is that inorganic content is higher than combustible component higher than Organic substance, non-combustible composition generally, Moisture content is higher, hazardness rubbish and domestic garbage mixing, does not has sound go-no-go system, proportion more than kitchen in Organic substance Relatively big, paper, plastics, rubber proportion are less；In external rubbish, paper ratio is bigger, reaches more than 35%, and calorific value also can reach 8.5MJ/kg；Therefore, can not simply imitate for external pyrolytic process and technology, it is necessary to base oneself upon foreign technology frontier development, According to China's urban development situation and rubbish feature, exploitation tallies with the national condition, the processing means of technical feasibility.Refuse pyrolysis gas Change processes: energy recovery is good, low in the pollution of the environment, the method being described as 21st century optimal and effective process rubbish； Refuse pyrolysis gasification is that the rubbish containing combustable organic thing utilizes under conditions of anoxia heat energy make the chemical combination key of compound break Split, the Organic substance of macromolecule be changed into CO, H of small-molecular-weight₂、CH₄Deng fuel gas, it suppresses the approach master of two English Having: decrease the generation of two English precursors, the valuable metal in rubbish does not has the metals such as oxidized, Cu, Fe in rubbish It is difficult to generate the catalyst promoting that two English generate；The pyrolytic gasification of rubbish also has its advantage simultaneously: prepare fuel gas, heat When solving gas combustion, coefficient of excess air is relatively low, can significantly lower exhaust smoke level, improve capacity usage ratio, reduce NOx discharge capacity, minimizing Fume treatment auxiliary investment and handling.

Just because of this, attracting research and the attention of national governments of numerous Chinese scholars, the U.S. is to carry out rubbish the earliest The country of pyrolytic gasification, 1970, " solid waste method " was made into " resource regeneration method " by the U.S., encouraged to reclaim combustion gas from rubbish And fuel oil, successively develop the multiple pyrolysis refuse gasification boilers such as Porox system, Garret system and EPA technology, achieve the biggest Progress.Europe is to use burning disposal rubbish the most the earliest, but burns the secondary pollution brought and become people's concern always Focus, in order to reduce secondary pollution, many countries add pyrolysis installation on the basis of burning, as Germany and the ELK stove of France, Kiener system stoves etc., there is abundant domestic garbage resources in Canada, and this state has formulated RD plan, starts with at rotary kiln gasification Reason solid waste, bears fruit, but more late than America and Europe's starting, and Japan implemented Star Dust80 plan from 1973, had carried out with rubbish Many experiments of rubbish pyrolytic gasification, such as Nippon Steel's system rubbish pyrolysis oven, it is thus achieved that practical, China processes for refuse gasification Studying more late, but risen the upsurge that " gasification " is studied in recent years, that is engaged in this respect work reaches family more than 2000, obtains many one-tenth Really, as elder brother's work formula rubbish direct gasification melting furnace puts into operation, Tsing-Hua University grinds jointly with Taiyuan Feng Ya Mechanical and Electrical Equipment Company The LSF vertical heater pyrolysis rubbish etc. of system.But, current domestic garbage gasification system whole efficiency is relatively low, and gasification product is many , tar low for calorific value and the high low-quality combustible gas of content of ashes, it is impossible to directly substitute house refuse, petroleum and natural gas etc. and change Stone fuel use, cause gasification technology less economical, commercial competitiveness is on the low side；Therefore, domestic garbage gasification skill how is promoted Art efficiency, improves combustible gas quality, be current domestic garbage gasification field urgently to be resolved hurrily important with topic.

Domestic garbage gasification technology i.e. utilizes gasifying agent to make house refuse imperfect combustion generate under high temperature atmosphere Containing H₂, the synthesis combustible gas of CO etc.；According to the difference of gasifying agent, domestic garbage gasification can be divided into: air gasification, oxygen gasified With steam gasification etc.；Air gasification low cost, appliance arrangement are simple, operation possibility is strong, but dilute due to by a large amount of nitrogen Releasing impact, the combustible gas calorific value of production is relatively low, the most only 3 ~ 5MJ/Nm³, the oxygen gasified impact reducing nitrogen, produce Gas calorific value is up to 9 ~ 12MJ/Nm³, work as with domestic waste gas phase, but the high cost prepared of pure oxygen limit that it promotes should With, use oxygen-rich gasification can effectively reduce cost.

The present invention, on the basis of comparative study various refuse pyrolysis gasification gas making technology, utilizes independently developed oxygen-enriched add Calming the anger gas producing technology, it is proposed that the new technology of high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish.

Summary of the invention

The technical problem to be solved is: a kind of process environment close friend of offer is pollution-free, refuse gasification boiler gasification Intensity is high, reduced investment is simple to operate, gasification gas rate is high, combustible gas calorific value is high, the house refuse that preparation method is more efficient and rational The method that high heating value combustion gas is produced in rich gas pressurization.

The technical solution used in the present invention is: provide the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish, It is characterized in that: house refuse adds the feeding warehouse of pyrolysis gasification furnace top pressurization through its top feed bucket, close valve on feeding warehouse After when being pressurized to identical with pyrolysis gasification furnace pressure, open valve under feeding warehouse, rubbish adds gasification furnace by gravity；By oxygen-rich concentration Reach the air pressurized of 50% to after 2.0-2.5MPa, be mixed into gasifying agent with the superheated vapour of 2.5MPa, from pyrolytic gasification furnace bottom Tower fire grate leads in pyrolysis gasification furnace, when rubbish moves in pyrolysis gasification furnace from top to bottom against air-flow upwards, and quilt Be dried, devolatilization, gasify, crack finally burn become 3 ~ 5% ashes；At about 2.5MPa, under conditions of 1200 DEG C, rubbish Rubbish material moves down, and heat moves with on air-flow, promotes rubbish generation pyrolytic gasification reaction of being heated, generates with CO, H₂、CO₂、CH₄It is main Want the high heating value combustible gas of composition；High temperature be enough to kill any pathogenic bacteria, and provides heat to support upper materials gasification reaction institute Need the heat absorbed；The thick combustible gas out from gasification furnace top, according to the difference of garbage constitution, temperature is at 500 ~ 650 DEG C Left and right, through waste heat boiler recovery waste heat, temperature is down to 250 DEG C, and waste heat boiler can produce the middle pressure steam of 3.0MPa；Cold through overspray After device cooling, temperature is down to about 30 DEG C, produces calorific capacity and is up to 12MJ/Nm³Combustible gas product；With the combustion-supporting heating of oxygen rich air The feature of technology, eliminate bring a large amount of nitrogen into air-breathing and improve product fuel gases calorific value, system is airtight at 2.5MPa Completing in gasification furnace container, the intensity of gasification of siege can bring up to 550 ~ 650kg/m².h。

Described gasifying agent flow-control is: 2000 ~ 3600kg/h, and the control of gasifying agent optimal oxygen content is: 48 ~ 52%, gas In agent, steam and oxygen proportion control are: 0.65 ~ 0.75kg/Nm³, gasification agent temperature control is: 115 ~ 125 DEG C.

The described pyrolytic gasification thick gaseous-pressure of outlet of still pyrolytic gasification controls: 2.5MPa.

The described grate range of speed control is: 1.5 ~ 2.5r/min.

The described pyrolytic gasification thick fuel gas temperature of outlet of still pyrolytic gasification controls :≤650 DEG C.

Described heat boiler outlet pyrolytic gasification fuel gas temperature controls: 250 DEG C.

Described scrubber cooler pyrolytic gasification gas outlet temperature controls: 30 DEG C.

Described waste heat boiler steam exit pressure controls :≤3.0MPa.

CO in the thick combustion gas of described pyrolytic gasification (dry gas)₂Content controls: 10 ~ 25%(volume).

In pressurized-gasification furnace, height and the temperature control of each bed are:

Bed title	/ mm highly (is counted) from fire grate	Temperature/DEG C
			Ash bed	0~300	450
Burning zone	300~600	1000~1250
			Gasification layer	600~1100	850~1000
Methane layer	1100~2200	550~800
			Dry distilling layer	2200~2700	350~550
Drying layer	2700~3500	350

Compared with prior art, it is an advantage of the current invention that: 1, the present invention is based on the feature with oxygen-enriched combustion-supporting heating technique, make raw Rubbish of living obtains complete thermal cracking, exempts and is heated a large amount of nitrogen brought into by air-breathing and then improve produced combustible gas heat Value；2, conventional pyrolysis gasification technology uses air, oxygen, water vapour or air (oxygen) to mix as gasifying agent with water vapour, Cost of investment and the balance of aerogenesis calorific value cannot be realized, cause combustible gas calorific value relatively low or system investments is relatively costly, in investment Becoming present aspect, compare pure oxygen gasification, oxygen concentration is required to decline by oxygen-rich gasification, and oxygen cost processed reduces；3, in usual air, oxygen contains Amount is 20.93%, nitrogen content is 78.1%, the most a small amount of noble gas etc., and therefore real oxygen the duty gas participating in burning is total Amount about 20%, not only and the nitrogen of duty gas total amount about 78.1% and other noble gases the most combustion-supporting, take away substantial amounts of on the contrary Heat, properly increases the oxygen content in gasifying agent so that it is participate in combustion gasification, has positive meaning for energy-conservation and environmental protection； 4, in terms of combustible gas quality, owing to oxygen rich gas nitrogen content is few, reaction rate is fast, and the thermal efficiency is higher, compares air gasification and produces Gas calorific value can improve by about one time, increases H in combustible gas due to steam gasification reforming reaction again₂With the concentration of C0, therefore The combustible gas calorific value of this technology institute output may be up to 10 ~ 12MJ/Nm³, improve benefit；5, pressurized gasification makes reaction rate Strengthening, the treating capacity of unit hearth area substantially increases, and in gasification furnace, the intensity of gasification is greatly improved, production efficiency and production energy Power is greatly improved.

Accompanying drawing illustrates:

Fig. 1 is the different oxygen-enriched content situation gasified combustion gas calorific capacity changing condition figure of the present invention.

Fig. 2 is the different oxygen-enriched content situation gasified combustion gas calorific capacity change scaling trend figure of the present invention.

Fig. 3 is the gasifying agent different pressures gasified Strength Changes figure of the present invention.

Fig. 4 is the technological process letter view of the present invention.

Fig. 5 is the technical process sketch of the present invention.

Fig. 6 is the table 1 numerical value figure of the present invention.

Fig. 7 is the table 2 numerical value figure of the present invention.

Fig. 8 is the table 3 numerical value figure of the present invention.

Fig. 9 is the table 4 numerical value figure of the present invention.

Figure 10 is the table 5 numerical value figure of the present invention.

Figure 11 is the table 6 numerical value figure of the present invention.

Figure 12 is the table 7 numerical value figure of the present invention.

Figure 13 is the table 8 numerical value figure of the present invention.

Figure 14 is the table 9 numerical value figure of the present invention.

Detailed description of the invention

As shown in Figure 4, Figure 5, the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish, it is characterised in that: raw Rubbish of living adds the feeding warehouse of pyrolysis gasification furnace top pressurization through its top feed bucket, closes and is pressurized to and is pyrolyzed after valve on feeding warehouse When gasification furnace pressure is identical, opening valve under feeding warehouse, rubbish adds gasification furnace by gravity；Oxygen-rich concentration reaches the air of 50% add After being pressed onto 2.0-2.5MPa, it is mixed into gasifying agent with the superheated vapour of 2.5MPa, leads to from pyrolytic gasification furnace bottom tower fire grate In pyrolysis gasification furnace, when rubbish moves against air-flow upwards in pyrolysis gasification furnace from top to bottom, it is dried, removes volatilization Divide, gasify, crack final burning and become the ashes of 3 ~ 5%；At about 2.5MPa, under conditions of 1200 DEG C, rubbish material moves down, heat Measure and move with on air-flow, promote rubbish generation pyrolytic gasification reaction of being heated, generate with CO, H₂、CO₂、CH₄High heat for main component Value combustible gas；High temperature be enough to kill any pathogenic bacteria, and provides heat to support the heat absorbed required for upper materials gasification reaction Amount；The thick combustible gas out from gasification furnace top, according to the difference of garbage constitution, temperature is at about 500 ~ 650 DEG C, through waste heat pot Stove recovery waste heat, temperature is down to 250 DEG C, and waste heat boiler can produce the middle pressure steam of 3.0MPa；After overspray cooler is lowered the temperature, temperature It is down to about 30 DEG C, produces calorific capacity and be up to 12MJ/Nm³Combustible gas product；With the feature of the combustion-supporting heating technique of oxygen rich air, exempt from Improve except bringing a large amount of nitrogen into air-breathing product fuel gases calorific value, system is complete in 2.5MPa airtight gasification furnace container Becoming, the intensity of gasification of siege can bring up to 550 ~ 650kg/m².h。

The described grate range of speed control is: 1.5 ~ 2.5r/min.

Described waste heat boiler steam exit pressure controls :≤3.0MPa.

The principle of the present invention:

1, the main chemical reactions kind in refuse pyrolysis gasification furnace has:

1) reaction between oxygen, steam in the carbon in rubbish composition and gasifying agent；

2) oxygen in gasifying agent, steam and various generation gas such as CO, CO₂、H₂、CH₄Reaction between Deng；

3) heat scission reaction of rubbish carbon compound, organic molecule etc.；

These three reaction is carried out in the different levels in gasification furnace；

2, the level of pyrolysis gasification furnace about can be divided into following which floor:

1) preparation layer:

1. drying layer: the moisture content in house refuse escapes from this layer；

2. dry distilling layer: be also called decomposition layer, after house refuse is hot cracked, wherein fugitive constituent and portion gas escape from this layer；

2) gasification layer:

1. reducing zone: steam H₂O reacts with carbon C, carbon dioxide CO₂With carbon C react generate pyrolysis gas activating QI major part: Hydrogen H₂With carbon monoxide CO；

2. oxide layer: oxygen O₂Generation carbon monoxide CO and carbon dioxide CO is reacted with carbon C₂；

3) ash bed: gasifying agent preheating and lime-ash cooling；

4) dead level: have a small amount of gas phase generated between gas and gasifying agent reaction；

Play main effect in pyrolysis gasification furnace is at gasification layer；

During the normal production run of pyrolysis gasification furnace, due to the oxidation reaction release heat of aerobic O and carbon C in stove, there is again titanium dioxide Carbon CO₂React with the endothermic reduction of carbon C and water vapour H₂The endothermic reaction of O and carbon C, can keep produce to be carried out continuously, thus hot Solving gasification furnace is gas the most processed.

3, reaction mechanism:

According to and the chemical reaction that carried out in utilizing pyrolysis gasification furnace, its Main change occurs at gasification layer, i.e. oxide layer and Reducing zone, rubbish is that first burning produces heat when gasification and pyrolysis, and then producing so that the heat produced makes to react further can Carbon monoxide CO and hydrogen H for burning₂, as not having heat, then next step generates carbon monoxide CO and hydrogen H₂Reaction just Can not carry out, burning is i.e. the oxidation reaction that carbon C rises with oxygen O, and oxidation can generate carbon dioxide CO₂, it is also possible to not exclusively Oxidation generates carbon monoxide CO, by carbon dioxide CO₂Raw CO₂Become carbon monoxide CO and by steam H₂It is anti-that O and carbon C is carried out Should be all reduction reaction, along with the raising of gasifying agent oxygen content, then increased flame speeds, create in unit interval and space More heat and carbon dioxide CO₂, the reduction for next step has prepared more sufficient reaction condition, and reducing zone can be divided into two Layer, the i.e. first reducing zone and the second reducing zone, the first reducing zone in the bottom of reducing zone, upper at reducing zone of the second reducing zone Layer, reaction main in the first reducing zone is:

C+C0₂=2C0-162405 kilojoule/kilomol

C+H₂0=C0+H₂-118821 kilojoules/kilomol

C+2H₂0=C02+2H₂-75237 kilojoules/kilomol

So three reactions from the first reducing zone are it will be seen that owing near oxide layer, in layer, temperature is high, reaction is easier to The reaction that caloric receptivity is many is carried out, such C+C0₂The chance of=2C0 reaction just compares many, C+H₂0=C0+H₂Take second place, minimum Reaction is C+2H₂0=C0₂+2H₂, so understand the C0 generated the most, and H₂Fewer, main in the second reducing zone Reaction be:

C0+H₂0=C0₂+H₂+ 43585 kilojoules/kilomol

C+C0₂=2C0-162405 kilojoule/kilomol

At the second reduction reaction layer, because it is away from oxide layer, so temperature ratio is relatively low, therefore for the most raw in the first reducing zone The CO become reacts with steam with this understanding and is converted to H₂, C0 simultaneously₂CO is generated again with coke, but due to the second reducing zone Temperature is low, thus this reaction to carry out speed slower.

Oxidation is carried out in oxide layer, and reduction is to carry out in reducing zone, and oxide layer and reducing zone are not have obvious boundary Line, the bottom of gasification layer is mainly oxide layer, is mainly reducing zone on the upper strata of gasification layer, but they still have staggered.

As shown in Figure 4, Figure 5, each gas componant distribution in each level:

(1) oxygen O₂: at ash bed Fails To Respond, dominant response is to react with carbon in oxide layer, at the end of oxide layer, and oxygen Gas O₂Level off to 0, containing only about 0.2% oxygen O in pyrolysis gas activating QI during normal gasification₂；

(2) carbon dioxide CO₂: it is to generate in oxide layer, when oxygen consumption is gradually reduced, carbon dioxide CO₂Just it is gradually increasing, When the top of oxide layer to the first reducing zone, due to carbon C and carbon dioxide CO₂Also play reduction reaction, so carbon dioxide CO₂ Just it is gradually reduced, when arriving the second reducing zone, carbon dioxide CO₂Decline slowly, have the most again rising, this is because an oxidation Carbon CO and steam H₂O reaction generates carbon dioxide CO₂Caused；

(3) carbon monoxide CO: be to generate the most region of carbon monoxide CO, now at oxide layer back segment and the first reducing zone Mainly carbon dioxide CO₂Play reduction reaction with carbon C and generate carbon monoxide CO, just have decline slightly on the second reducing zone top Trend, by after at dead level partially due to carbon monoxide CO and steam H₂O generates carbon dioxide CO₂, and now carbon monoxide CO is just There is downward trend；

(4) steam H₂O: mainly consume at the first reducing zone and the second reducing zone, also has a small amount of consumption in dead level；

(5) hydrogen: mainly generate at the first reducing zone, also has a small amount of generation in the second reducing zone and dead level；

Such certain law can be obtained from the consumption of the most various gases and the situation of generation:

1. the consumption of oxygen O and carbon dioxide CO₂Generation be one to disappear and one rise, the decline of oxygen O could promote carbon dioxide CO₂Raw Become；

2. carbon dioxide CO₂Also it is one to disappear a relation risen with carbon monoxide CO；

3. steam H₂O and hydrogen H₂Substantially there is also one to disappear a relation risen；

These rules can instruct us to grasp gasifying agent oxygen content, gasification temperature, saturation temperature in practical operation, so that Obtain more preferable gasification result.

4, water vapour decomposition mechanism

In rubbish material, the reaction between carbon and water vapour is primary first-order equation, and it is to air-vapor or oxygen-water vapour Condition gas-making process has important impact, and water vapour decomposes can following reaction:

C+H₂O=CO+H₂—28150kcal/kg

C+2H₂O=CO₂+2H₂--17900kcal/kg

CO+H₂O=CO₂+H₂--10250kcal/kg

Water vapour decomposition reaction is also the process that there is chemisorbed；

(1) water vapour adsorbs at the surface physics of carbon；

C+H₂O——C+H₂O (adsorbs)

(2) carbon in so expecting forms intermediate complex with water vapour, and this is chemisorbed.Decomposite in the moment forming complex The hydrogen adsorbed by carbon surface, hydrogen is then under high temperature action gradually under desorbing；

C+H₂O (absorption) CxOy+H₂(absorption)

H₂(absorption) H₂

(3) intermediate complex at high temperature decomposes or forms CO with steam reaction in gas phase；

CxOy CO (absorption)+C

CO (absorption) CO or CxOy+H₂O CO (absorption)+H₂

Along with flowing up of steam and oxygen, five different sections can be characterized as in pyrolysis bed, arrive top bottom-up Portion, is ash bed, the first conversion zone (burning zone of carbon, the heat needed for supply gasification), the second conversion zone, dry distilling layer respectively (devolatilization) and drying layer；When rubbish is declined by bed, first some volatile matters in rubbish are removed, and then remain Remaining carbon is gasified and is burnt；Bottom gasification furnace, lime-ash is drained in ash lock, then send disposal outside.The pyrolysis that gasification furnace generates Thick combustion gas of gasifying is left away from furnace roof；It is added to the raw material rubbish of reactor, with the product gasification gas phase contact of heat, the moisture in rubbish Displaced；The thick pyrolytic gasification fuel gas temperature leaving gasification furnace is different regarding rubbish composition, generally 500 DEG C～650 DEG C.

5, the response speed principle of heterogeneous system

The reaction of heterogeneous system refers to carbon and gas (O on the interface of fixed carbon phase₂、H₂O、CO₂Deng) between the reaction that carries out.

In heterogeneous system, chemical reaction is to carry out on the interface of biphase (gas, solid), the most here, and reactant Molecule can collide.Therefore, the response speed of heterogeneous system is in addition to being affected by factors such as temperature, pressure, concentration, also with two Between Xiang, the size of contact surface is relevant.

Refuse gasification process is a heterogeneous system chemical reaction process, is fixed carbon and the process generating solid/liquid/gas reactions.Its Can be expressed as: the inhomogeneous reaction of solid+gas=another gas type.

Show to carry out reaction at solid and generally can be divided into three phases:

First, reactant molecule shows to solid from gas phase zone through air film diffusive transport；

Second, reaction molecular is shown to adsorb by solid, and carries out chemical reaction；

3rd product molecule shows desorbing from solid, and again leaves solid through air film and show；

From said process, the response speed of heterogeneous system, depend not only on the speed of action in terms of chemical kinetics, and Relevant with the gas diffusion velocity of first or phase III.If diffusion velocity is fast not as good as chemical reaction velocity, the most total reaction Speed is limited by diffusion velocity, and secondary condition is referred to as diffusion region.With secondary contrary then be referred to as power-section；Transition region is become between twoth district Or mesozone.

Diffusion velocity is from Fick's law: increase air velocity, improves temperature, pressure (pressure raising gas density increasing The gas density impact on the air-film thickness of carbon surface, the significantly larger than pressure impact on diffusion coefficient greatly) all can improve expansion Dissipate speed.

According to chemical reaction rate and chemical reaction equilibrium principle, improve reaction pressure and be conducive to chemical reaction to contract to volume Little opposite direction moves, and improves reaction temperature, and chemical reaction then moves to the direction of heat absorption.

Embodiment 1

7-8 month in 2014, oxygen generation system shuts down altogether 3 times, is wherein for 2 times program control fault, asks longer during shutdown, 1 time because of The bad deadlock of CPU backboard wire contacts, is for 1 time repairing planned to oxygen station；Within 2014, JIUYUE starts normal production on the 5th, due to Having the experience of last month, the comparison of furnace control is steady, has loaded onto oxygen content on-line detector and carry out oxygen-containing on oxygen-enriched air accumulator Amount monitoring；Selected 3200mm pyrolysis gasification furnace presses oxygen enriching content: 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70% formulating testing program, design gasifying agent saturation temperature is 50 DEG C ± 2 DEG C, and every kind of oxygen content also carries out one week The calorific capacity tracking and monitoring of the pyrolytic gasification gas of i.e. 7 days, every day, class Three was the most properly functioning, and per tour samples once, and every day takes 3 Individual sample, averages, run abnormal unstable time after be supplemented with sampling, sample 21 under an oxygen content state, obtain 7 It synthetic data carries out graphic analyses；Oxygen-enriched gas processed has been carried out preliminary exploration.

Owing to device is at the load operation initial stage, Equipment starting and stopping device is frequent, the phase ask stove in once occurred in various degree Oxide layer elongation, the phenomenon such as slagging scorification, the oxygen-rich gasification phase working of a furnace is the most stable, and index has some improvement；In oxygen-enriched input or When exiting, the working of a furnace is difficult to grasp, and gas quality fluctuation ratio is relatively big, once is forced to exit maintenance because the working of a furnace deteriorates；Although running into indivedual Sequencing valve cuts out the gas leakage of not in place, Water-ring vacuum system, ups power can not work, material in PLC system in case of system halt and oxygen-enriched rear stove Layer moves the problems such as fast, but related personnel is in practice, has understood and grasped operation principle and the operant skill of system, always Bear a set of effective operational approach, have accumulated experience for next step test.Record takes such as Fig. 6-Fig. 9:

It will be seen from figure 1 that oxygen-enriched gas-made technology skilled industry application is feasible, pyrolytic gasification under conditions of oxygen-enriched resultant difference Gas quality obtains lifting in various degree；When oxygen-enriched content 50%, gasification gas calorific capacity reaches peak, about 9.8MJ/NM³, Oxygen content continues to raise, and gasification gas calorific capacity no longer raises, and has declined than the oxygen content calorific capacity when 50% on the contrary；From Fig. 2 Changing scaling trend figure it can also be seen that ratio reaches maximum when oxygen-enriched content 50%, continue to increase oxygen-enriched content, gasification is fired Gas calorific value is on a declining curve, and therefore the optimal oxygen content of First air is appropriate in 50% ± 2% scope.

Conclusion: 3200mm pyrolysis gasification furnace implements oxygen-enriched gas-made technology, technical feasibility, equipment are suitable for, oxygen-rich gasifying agent First air oxygen content control 48% ~ 52% to be both economical feasible.

Embodiment 2

In December, 2014, through trimestral experimentation repeatedly, oxygen-enriched pressure-swing absorption apparatus runs and tends towards stability, stoker couple The accreditation of the application of oxygen enrichment technology, operation level is improved.

Experimental period, asks, we have not only found out the ruuning situation of producer, oxygen station, has also made the data gathered point Analysis, has carried out effective control: gasifying agent flow is 2000 ± 3600m to pyrolysis gasification furnace key operating parameters³/ h, saturated temperature Degree is 115 ~ 125 DEG C, and it is 500 ~ 650 DEG C that stove goes out temperature, has grasped pyrolysis gas activating QI composition, calorific value and benefit and has become with oxygen-rich concentration The rule changed；Due to JIUYUE, the ratio increase of oxygen-enriched feeding gasification furnace causes the working of a furnace wayward, and index rebounds, data acquisition Not, the most representative, therefore the data of JIUYUE only do technology determination, do not include benefit calculation in；Seminar from on-the-spot actual with become This consideration determines that primary air oxygen-enriched content controls at 50%(48% ~ 52%) between again carry out pressurization in stove and carry product and test, End on March 10th, 2015 and obtain the inventory record under 60 days steady operational status altogether；Pressure test scheme is: 0.5MPa, Several state of 1.0MPa, 1.5MPa, 2.0MPa, 2.5MPa, 3.0MPa, 3.5MPa, 4.0MPa is tested, and record takes such as figure 10-Figure 14:

It is seen from figure 14 that pressurization gas-made technology skilled industry application is feasible, it is pyrolyzed under conditions of gasifying agent pressurization difference The intensity of gasification of gasification furnace obtains lifting in various degree, and inventory strengthens, and when gasifying agent is pressurized to 2.5MPa, gasification furnace is thrown Doses that is the intensity of gasification reach peak, about 620kg/m².h, during contrast atmospheric gasification, the intensity of gasification has brought up to 220%, effect Fruit is clearly；Class's inventory of pyrolysis oven nearly 40 tons, but when continuing to add vapor pressure in blast furnace, the intensity of gasification no longer rises High, class's inventory declines on the contrary, from Fig. 3 intensity of gasification changing trend diagram it is also seen that: add take by force to 2.5MPa time pyrolysis oven Disposal ability reach maximum；Class's yield reaches 40 tons, continues to increase furnace pressure amount, and the intensity of gasification is on a declining curve, therefore Gasifying agent pressurization scope is appropriate at 2.5MPa.

Further, since gasifying agent is oxygen-enriched and after pressurization, in stove, chemical reaction aggravation, brings necessarily to stoker's post operation Difficulty, post employee is the most inadaptable.

In March, 2015, continue to lift up gasification pressure business in stove according to plan, when stove in vapor pressure is increased or decreased, The working of a furnace is difficult to control: in all causing producer, the bed of material is easily turned over, and the bed of material is partially formed wind-tunnel, the phenomenon such as burn with anger, and makes furnace temperature Rise too fast, be easily caused the working of a furnace, impact gasification makings amount, yield.

The part index number under equal conditions adding compacting gas there occurs change, as saturation temperature, stove go out temperature and raise, and gasification Reaction is accelerated, and operation easier strengthens, and adjusts the working of a furnace frequent, in order to prove steel material and the furnace building material i.e. work of original gasification furnace Whether skill changes after in-furnace temperature increases, and November 11, pyrolysis gasification furnace was in a planned way moved back stove inspection by us, Engineers and technicians on the scene are confirmed for problems with point:

A, the degree of wear of fire grate 15# cast steel of abrasion are judged, the degree of wear is in normal range；

Whether b, stove internal jacket outward appearance deform or superficial charring etc., and water jacket is working properly, and material is the most abnormal；

C and fire the material i.e. change of brickwork adaptation condition；

Conclusion: pyrolysis gasification furnace implements pressurization gas-made technology, technical feasibility, and equipment is suitable for, gasifying agent pressurization scope is at 2.5MPa Both economical feasible.

Claims

1. the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish, it is characterised in that: house refuse is through its top feed Bucket adds the feeding warehouse of pyrolysis gasification furnace top pressurization, closedown feeding warehouse is pressurized to identical with pyrolysis gasification furnace pressure after valve Time, open valve under feeding warehouse, rubbish adds gasification furnace by gravity；Oxygen-rich concentration is reached the air pressurized of 50% to 2.0-2.5MPa After, it is mixed into gasifying agent with the superheated vapour of 2.5MPa, leads in pyrolysis gasification furnace from pyrolytic gasification furnace bottom tower fire grate, when When rubbish moves against air-flow upwards in pyrolysis gasification furnace from top to bottom, it is dried, devolatilization, gasifies, crack Burning becomes the ashes of 3 ~ 5% eventually；At about 2.5MPa, under conditions of 1200 DEG C, rubbish material moves down, and heat moves with on air-flow, promotees Make rubbish generation pyrolytic gasification reaction of being heated, generate with CO, H₂、CO₂、CH₄High heating value combustible gas for main component；High temperature foot To kill any pathogenic bacteria, and provide heat to support the heat absorbed required for upper materials gasification reaction；From gasification furnace top Thick combustible gas out, according to the difference of garbage constitution, temperature is at about 500 ~ 650 DEG C, through waste heat boiler recovery waste heat, temperature Being down to 250 DEG C, waste heat boiler can produce the middle pressure steam of 3.0MPa；After overspray cooler is lowered the temperature, temperature is down to about 30 DEG C, produces Hair growth promoting calorific value is up to 12MJ/Nm³Combustible gas product；With the feature of the combustion-supporting heating technique of oxygen rich air, eliminate with air-breathing Bringing a large amount of nitrogen into and improve produced fuel gases calorific value, system completes in 2.5MPa airtight gasification furnace container, the gasification of siege Intensity can bring up to 550 ~ 650kg/m².h。

2. the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish described in claim 1, it is characterised in that: described Gasifying agent flow-control be: 2000 ~ 3600kg/h, the optimal oxygen content of gasifying agent control be: 48 ~ 52%, steam in gasifying agent With oxygen proportion control it is: 0.65 ~ 0.75kg/Nm³, gasification agent temperature control is: 115 ~ 125 DEG C.

3. the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish described in claim 1, it is characterised in that: described The pyrolytic gasification thick gaseous-pressure of outlet of still pyrolytic gasification control be: 2.5MPa.

4. the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish described in claim 1, it is characterised in that: described The grate range of speed control be: 1.5 ~ 2.5r/min.

5. the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish described in claim 1, it is characterised in that: described The pyrolytic gasification thick fuel gas temperature of outlet of still pyrolytic gasification control be :≤650 DEG C.

6. the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish described in claim 1, it is characterised in that: described Heat boiler outlet pyrolytic gasification fuel gas temperature control be: 250 DEG C.

7. the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish described in claim 1, it is characterised in that: described Scrubber cooler pyrolytic gasification gas outlet temperature control be: 30 DEG C.

8. the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish described in claim 1, it is characterised in that: described Waste heat boiler steam exit pressure control be :≤3.0MPa.

9. the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish described in claim 1, it is characterised in that: described The thick combustion gas of pyrolytic gasification (dry gas) in CO₂Content controls: 10 ~ 25%(volume).

10. the method that high heating value combustion gas is produced in the oxygen-enriched pressurization of one way of life rubbish described in claim 1, it is characterised in that: add In pressure gasification furnace, height and the temperature control of each bed are: