Kinematics of diffuse ionized gas in the disk halo interface of NGC 891 from Fabry-P'erot o

a r X i v :a s t r o -p h /0703363v 1 14 M a r 2007

Astronomy &Astrophysics manuscript no.astroph c

ESO 2008February 5,2008

Kinematics of diffuse ionized gas in the disk halo interface of NGC

891from Fabry-P′erot observations

P.Kamphuis 1,R.F.Peletier 1,R.-J.Dettmar 2,J.M.van der Hulst 1,P.C.van der Kruit 1,and R.J.Allen 3

1Kapteyn Astronomical Institute,University of Groningen,Postbus 800,9700A V Groningen,the Netherlands

2Astronomisches Institut,Ruhr-Universitt Bochum,Universit¨a tsstrasse 150,D-44780Bochum,Germany 3

Space Telescope Science Institute,3700San Martin Drive,Baltimore,MD 21218,USA

Preprint online version:February 5,2008

ABSTRACT

Context.The properties of the gas in halos of galaxies constrain global models of the interstellar medium.Kinematical information is of particular interest since it is a clue to the origin of the gas.

Aims.Here we report observations of the kinematics of the thick layer of the di ?use ionized gas in NGC 891in order to determine the rotation curve of the halo gas.

Methods.We have obtained a Fabry-P′e rot data cube in H αto measure the kinematics of the halo gas with angular resolution much higher than obtained from HI 21cm observations.The data cube was obtained with the TAURUS II spectrograph at the WHT on La Palma.The velocity information of the di ?use ionized gas extracted from the data cube is compared to model distributions to constrain the distribution of the gas and in particular the halo rotation curve.

Results.The best ?t model has a central attenuation τH α=6,a dust scale length of 8.1kpc,an ionized gas scale length of 5.0kpc.Above the plane the rotation curve lags with a vertical gradient of -18.8km s ?1kpc ?1.We ?nd that the scale length of the H αmust be between 2.5and 6.5kpc.Furthermore we ?nd evidence that the rotation curve above the plane rises less steeply than in the plane.This is all in agreement with the velocities measured in the HI.

Key words.H α,NGC 891,Gaseous Halos,Fabry-P′e rot,Edge-on,Galaxies,Kinematics,Dynamics

1.Introduction

Over the last decade,di ?use ionized gas (DIG)in the halos of spiral galaxies has been identi?ed as an important constituent of the interstellar medium (ISM).The detection of an extended layer of DIG in NGC 891(z NW =0.5kpc,z SE =0.3kpc,Dettmar (1990)),which was found to be similar to the extended layer of DIG,or Reynolds layer,(Reynolds,1990)of the Milky way (Dettmar,1990;Rand et al.,1990),was followed by several H αimaging searches.By now,many results on ‘normal’(i.e.,excluding nuclear starbursts)edge-on galaxies have been pub-lished (Dettmar,1992;Rand et al.,1992;Pildis et al.,1994a;Rand,1996;Rossa &Dettmar,2003).Rossa &Dettmar (2003)cataloged 74galaxies and found about 40%to have extraplanar di ?use ionized gas (eDIG).In those objects showing H αemission from the halo,a wide range of the spatial distributions have been found,from thick layers with ?laments and bubbles (NGC 4631,NGC 5775)(Dettmar,1990;Rand et al.,1990;Pildis et al.,1994b;Hoopes et al.,1999;Miller &Veilleux,2003)to individual ?laments and isolated plumes (e.g.,UGC 12281)(Rossa &Dettmar,2003).For only a few of them there is evidence for widespread DIG in the halo comparable to that in NGC 891.In this galaxy the DIG is distributed in long ?laments and bubbles of ionized gas embedded in a smooth background.Since its emission line spectrum is rather easily accessible by optical imaging and spectroscopy,the DIG component is an important tracer of the ISM halo in other galaxies.This is true particularly since most other tracers,such as radio continuum from cosmic rays or X-rays from hot plasma,cannot be observed either with comparable angular resolution or with su ?cient sensitivity.

The origin and ionization source of the DIG component is still under debate and gives important constraints for models of the ISM in general and on the large-scale exchange of matter between disk and halo in particular (e.g.,Dettmar,1992;Rand,1997).

Theorists describe the disk-halo interaction by means of galactic fountains (Shapiro &Field,1976;Bregman,1980;de Avillez &Breitschwerdt,2005),chim-neys (Norman &Ikeuchi,1989),and galactic winds (Breitschwerdt et al.,1991;Breitschwerdt &Schmutzler,1999).Possible models trying to explain gaseous galaxy halos as a consequence of stellar feedback therefore depend on many factors,such as supernova rates,galaxy mass,magnetic ?elds and the vertical structure of the ISM.

NGC 891and NGC 4631are two galaxies with extensively studied ISM halos.Both of them not only show prominent thick layers of DIG,they also have extended radio continuum,HI,and X-ray halos.The spatial correlation of radio continuum emission,indicative of cosmic rays in a magnetic ?eld found in a thick disk,and extra-planar DIG has been discussed for NGC 891in detail (Dettmar,1992;Dahlem et al.,1994).

If the DIG and other components of the ISM in the halo are due to dynamical processes,important information on its origin and ionization could come from kinematic studies.In the case of NGC 891a ?rst study was made by Keppel et al.(1991).Subsequent studies show that there is evidence for peculiar velocities of DIG.Pildis et al.(1994b)?nd a maximum di ?erence with the HI rotation curve δv max =40km s ?1;Rand (1997)retrieves a di ?erence in the observed mean velocity of 30km s ?1between velocities at z =1kpc and z =4.5kpc.Also in

2P.Kamphuis et al.:Kinematics of di?use ionized gas in the disk halo interface of NGC891from Fabry-P′e rot

observations

Fig.1.This channel of original wavelength calibrated data cube at v=674km s?1demonstrates the contamination by night sky lines with varying intensity(left).The e?ect of removing a model for the night sky contribution from averaging in rings is seen on the right.

the HI peculiar velocities are observed(Fraternali et al.,2005; Swaters et al.,1997).For both components,a deviation from corotation is observed on scales of2kpc above the disk in the sense that the gas rotates more slowly than expected.This “lagging”has been found to have a gradient of dV rot/dz=-15km s?1kpc?1in HI(Fraternali et al.,2005).Recent SPARSE-PAK observations(Heald et al.,2006)show a similar result for Hα.

In order to understand this lagging,hydrostatic models have been investigated.These models are able to reproduce the lag of the halo of NGC891in HI(Barnab`e et al.,2006). However,the stability of these models remains unresolved.

A di?erent approach to understanding the lag of halos are ballistic models(Collins et al.,2002;Fraternali&Binney, 2006).Fraternali&Binney(2006)are able to reproduce the vertical HI distributions of NGC891and NGC2403this way. However,their model fails in two important aspects:(1)they do not reproduce the right gradient in rotation velocity;(2)for NGC2403they predict a general out?ow where an in?ow is observed.

It is clear that improved data on the detailed kinematics of the extra-planar DIG would be very useful to a further physical understanding of the phenomenon.

Here we present a full velocity cube for the DIG in NGC891 from observations with the TAURUS II imaging Fabry-P′e rot spectrograph.As a byproduct,we obtain a very clean map of the Hαdistribution.NGC891has a systemic velocity of 528km s?1(RC3)and we assume a distance of9.5Mpc (van der Kruit&Searle,1981).At this distance1arcmin cor-responds to2.8kpc physical size.We present the observations in§2and the data reduction steps in§3.§4will show the results that can be obtained by rebinning the data.In§5we will present models for the gas distribution and these models will be discussed and compared to the data in§6.We will summarize and conclude in§7.

2.Observations

The data were obtained during two nights in November1992 with the TAURUS II imaging Fabry-P′e rot spectrograph at the William-Herschel Telescope on La Palma.The attached EEV3 CCD detector with a pixel size of22.5μm provided an im-age scale of1.”04/pixel with a binning by2.An interference ?lter with central wavelength atλ=657.7nm and a

bandpass Fig.2.Model for the night sky contribution obtained by averag-ing in rings as used for the channel shown in Fig.1.

Nov16/1719923559NE19:29 1.03

3564SW00:44 1.05

Nov17/1819923581NE21:46 1.04

3583NE01:09

1.10

P.Kamphuis et al.:Kinematics of di?use ionized gas in the disk halo interface of NGC891from Fabry-P′e rot observations3

The rebinned images still contained the night sky lines.The strong OH night sky lines atλ=6568.78?andλ=6577.28?were used to establish the absolute wavelength calibration.They also provide a check on the channel step size.The?λ=0.02742 nm determined this way is in excellent agreement with the de-termination from the afore-mentioned calibration cube and cor-responds to12.5km s?1at Hα(for Fabry-P′e rot data reduc-tion techniques see Bland&Tully(1989);Jones et al.(2002)). The pro?le of the night sky lines also provides information on the spectral resolution,which was determined to be40.7km s?1(FWHM).The formal errors of the Gaussian?ts to the OH-night sky lines allowed us to estimate the error of the wavelength scale to be less than6km s?1.A correction to the observed veloc-ity of-4.2km s?1was needed to obtain the heliocentric velocity.

At this stage,one remaining problem was caused by the re-distribution of the varying line intensity of the night sky lines during the integration of the observed cube into a wavelength cube.Rebinning of the lines into the appropriate wavelength channels resulted in a strong pattern of rings.In the left-hand panel of Fig.1,we show this e?ect for the worst case.To over-come this artifact for all a?ected channels the rings of the line emission were cut out interactively in areas well separated from the galaxy by using the GIPSY routine BLOT.The result was integrated using the routine ELLINT using the center as deter-mined from the phase calibration and the mean value in indi-vidual rings was used as a model.Such a ring model is given in Fig.2.The subtraction of the model resulted in general in a satis-factory reduction of the artifact as demonstrated in the right hand panel of Fig.1.Typically,the resulting residuals are smaller than the noise level of the night sky.This can be judged from the right panel in Fig.1.However,some of the channels showed residual larger than the noise level of the night sky.These residual rings were masked manually.

These cleaned and wavelength-calibrated data cubes covered a velocity range of940km s?1,su?ciently large to provide us with a scaled sum of continuum channels to correct for the con-tinuum.This continuum correction also removed all ghost im-ages from internal re?ections of the instrument.

We?ux calibrated the observations by comparing7HII re-gions in the integrated velocity map with the calibrated Hαim-age from Heald et al.(2006).4of these regions were located in the NE pointing and3in SW pointing.We estimate the uncer-tainty of this calibration to be～10%.

For the merging of all data and for comparison with other data sets,in particular the HI map provided by Fraternali et al. (2005),astrometry was performed.Since the two?elds do not su?ciently overlap,we used?ve stars with positions obtained from DSS to re-grid the two?elds into a common map.The as-trometric accuracy from the?ts to the stars is～2arcsec.Finally the data cubes were combined into one cube,rotated by42de-grees in position angle to be oriented along the major axis and cut back to42channels to cover the velocity spread in NGC 891.The noise in a channel in the fully reduced and calibrated cube is1.2×10?18erg s?1cm?2arcsec?2in the NE pointing and 1.4×10?18erg s?1cm?2arcsec?2in the SW.

4.Results

For the following analysis,in order to obtain a better S/N,the data were binned.In order maintain resolution in higher emis-sion parts,this was done in such a way that the length and width of a bin increases exponentially as the distance to the major and minor axis increases.For the North-East side of the galaxy no binning was applied when the S/N in a pixel was≥4.The channel at the systemic velocity(v sys=528km s?1) was set to0km s?1and all velocities given are o?sets from this channel.The central position was determined by eye in several Palomar Sky Survey and2MASS images to be RA=2h22m33.0s, DEC=42?20′51.5”and set to0in the images.From the scatter of the central position in the di?erent bands we determine the error to be less than2arcsec.Notice that this value di?ers from the best determined position given by the NASA Extra-galactic Database by almost6arcsec in declination.

For display purposes the?gures shown in this paper come from a cube which was masked so that only regions with signal are shown.The mask was constructed by smoothing the original binned cube with a Gaussian of4arcsec FWHM,which was cut at the1σlevel.

4.1.Channel maps

In Figs.3and4we give the resulting channel maps of Hαemis-sion with a velocity step size of?v=12.5km s?1.In the follow-ing?gures,the NE part of the galaxy is to the left;this is also the approaching side of the galaxy.Data are missing in small wedges along the minor axis,as we had underestimated the vignetting of the?eld when the required overlap of the?elds was determined. It is noteworthy that a thick component in the Hαemission is al-ready visible in individual channel maps.This sudden thickening of the Hα-emitting gas layer was reported before from Hαimag-ing(Rand et al.,1990;Dettmar,1990;Pildis et al.,1994b).The channel maps also clearly show a dichotomy between the NE and SW part of the galaxy with regard to the overall intensity level of the Hαemission.This was already noted by Rand et al. (1990)and can be seen most clearly in the spectacular color im-age of NGC891obtained by Howk&Savage(1997)(their Fig.

1)which shows a line of blue knots all along the north side at |z|=0,and no such features on the south side.This dichotomy is also seen in the distribution of the non-thermal radio contin-uum emission.(Hummel et al.,1991)

4.2.Hαdistribution

The dichotomy discussed in§4.1is seen even better in the to-tal Hαdistribution,which is shown in Figure5.This image was obtained by integrating all channel maps along the velocity axis of the cube.It clearly shows that the di?use ionized gas(DIG) extends beyond our?eld of view in several places.On the NE side of the galaxy our whole image is?lled with low-level emis-sion;on the SW side,however,we are not able to distinguish more than the major axis of the galaxy.This suggests that the di?erence in intensity is a physical e?ect and not a line-of-sight e?ect(see further discussion§6.2).For comparison we added a F-band image from the POSS II,below the Hαimage.

4.3.Velocity?eld

Fig.7shows the velocity?eld of our Hαcube.This velocity ?eld is determined by?tting a Gaussian pro?le to the line pro?le in each bin,the peak of this Gaussian is considered to be the velocity in this bin.This way we do not measure the real rotational velocity but an apparent mean velocity which is determined by a combination of the rotational velocity,the density distribution of the gas,and the opacity of the dust.This velocity will be referred to as the mean velocity.We chose the Gaussian?t because in the places where the underestimation of the rotational velocity is most signi?cant(major axis,center of

4P.Kamphuis et al.:Kinematics of di?use ionized gas in the disk halo interface of NGC891from Fabry-P′e rot observations

Fig.3.The velocity channel maps of the approaching side for the binned Hαof NGC891.The contours are at25.3,51,510×10?19 erg s?1cm?2arcsec?2.The horizontal and vertical dashed lines indicate the major and minor axis respectively.

P.Kamphuis et al.:Kinematics of di?use ionized gas in the disk halo interface of NGC891from Fabry-P′e rot observations5

Fig.4.Same as?g.3,for the receding side.

6P.Kamphuis et

al.:Kinematics of di

?use ionized gas in the disk halo interface of NGC 891from Fabry-P′e rot observations

Fig.5.H αdistribution from NGC 891as obtained from integrating the binned channel maps.The black contours are at 1.0and 10.0

×10?17erg s ?1cm ?2arcsec ?2.Red contours are the best ?t model (see §5.3)The horizontal and vertical dashed lines indicate the major and minor axis respectively.

Fig.6.R -band image taken from the Palomar Sky Survey for comparison with the H αdistribution.The horizontal and vertical dashed lines indicate the major and minor axis respectively.

the galaxy)the H αis optically thick (see discussion).

On the NE side we see a regular velocity ?eld which resembles solid body rotation with some lower velocities in the bins at |z |=60arcsec.This would indicate that the H αlagging does not begin below 60arcsec (2.8kpc).However,as the optical depth declines we expect to look deeper into the galaxy.This would mean that we are receiving more emission from the line of nodes the further we are from the plane of the galaxy.Since the real rotational velocity should be determined at the line of nodes our underestimate of the velocity would be less the further we look into the galaxy.So for a cylinder with a declining optical depth in the |z |-direction and solid body rotation we would expect the mean velocities to rise as the distance from the major axis increases.This is not the case for NGC 891as we can see in Fig.7.

If we look at Fig.7and follow the -200km s ?1contour we see that,starting from major axis,the mean velocity ?rst rises until ～20arcsec above the plane.Then the mean velocity starts to drop up to ～60arcsec.Above this the mean velocity starts to rise again but it is unclear whether this is real or a combined e ?ect of the binning and Gaussian ?t.

Looking at the South-West side of the velocity ?eld we see that this side is much more irregular in velocity than the

North-East side.Following the 100km s ?1contour we see a behavior similar to that of the -200km s ?1contour only much more extreme.Since on the SW side above ～60arcsec there is no emission it is unclear if the mean velocity would start to rise again above this height.

5.Models

5.1.Position -Velocity diagrams

An examination of ‘Position -Velocity diagrams’(PV dia-grams)provides the basis for our discussion of the H α.These di-agrams are another representation of the channel map data from Figs.3and 4,where now the pro?les are extracted at each point along a locus of positions in the image of the galaxy and plot-ted as contours in the PV plane.Figure 8is one example of this representation;here the position (x-axis)is measured along the major axis of the galaxy through the nominal center at |z |=0,and on the y-axis radial velocity is given.The color scale rep-resents the H αsurface brightness observed at each position;for instance,the H αline pro?le at the position located 1arcmin to the North of the galaxy center would be a line parallel to the

P.Kamphuis et al.:Kinematics of di?use ionized gas in the disk halo interface of NGC891from Fabry-P′e rot observations7

Fig.7.The velocity?eld of the observed Hαdetermined by a Gaussian?tting to the line pro?les.The contours are at-200,-100,0, 100,200km s?1and are with respect to the systemic velocity of528km s?1.The horizontal and vertical dashed lines indicate the major and minor axis respectively.

h g(kpc)6.5/5.5 3.0/2.5 5.0

z g(kpc)0.8/0.80.8/0.80.8

h d(kpc)8.1/8.18.1/8.18.1

z d(kpc)0.26/0.260.26/0.260.26

τHα4-6/612-14/13-146

σv(km s?1)40/4040/4040

R max21/1421/1414

8P.Kamphuis et al.:Kinematics of di ?use ionized gas in the disk halo interface of NGC 891from Fabry-P′e rot

observations

Fig.8.Color plot of the H αPV-diagram along the

major axis

overlaid with contours of Model 1and 2(see Table 2)corre-sponding to the upper and lower limit which can be ?tted.White contours are the data at 3σ,6σ,12σand 48σ.Black contours are Model 1.1with τH α=5,red contours are Model 2.1with τH α=13.The black arrow indicates the place where the ?ts deviate from the data (see text).

disk.

Koopmann et al.(2006)recently found that on average the H αscale length for a ?eld galaxy is on average 14%longer than the stellar scale length.Based upon the value found by Xilouris et al.(1998)in the V -band this would mean that the de-projected H αscale length for NGC 891should be ～6.5kpc which is in agreement with our limits.

Although the central attenuation for a given scale length is quite well constrained,the di ?erences in dust attenuation can be quite large between the di ?erent scale lengths.This gives us another handle on which scale length is correct.Xilouris et al.(1998)found a central optical depth of τface ?on =0.7±0.01in V -band,for the galaxy seen face on.For our models for this edge-on galaxy this would translate to a central attenuation of τH α=10.9.τH αin our models is the optical depth at a radial and vertical o ?set of 0along the line of sight to the center of the disk.

We consider the model with h d =5.0kpc,τH α=6and R max =14kpc (Model 3)the best ?t.Fig.9is an example of the major axis PV diagram of the data overlaid with contours of Model 3.Given the dependence of the central optical depth on scale length our results are not in disagreement with Xilouris et al.(1998).

Fig.9.Color plot of the H αPV-diagram along the major axis overlaid with the contours of the best ?t model.White contours are the data at 3σ6σ12σ48σ.Black solid contours are Model 3(Table 2).

5.3.Image-model

After we ?tted the PV-diagram on the major axis we put the same values into a FORTRAN code which calculates an inten-sity along the line of sight (see §5.1).This code produces a model image which we can compare with the observed images of NGC 891.To determine the correct scale height we compare an intensity cut parallel to the minor axis averaged between -100to -50arcsec of the model images to the observed H αdistribu-tion averaged over the same region (Fig.5).Since at this point we are interested only in the vertical shape above the dust,the maps are ?rst normalized to their emission 30arcsec above the plane.To determine the best ?t we concentrate on the emission at a positive o ?set of the plane since this side is brightest.In our ?t we only consider the emission at o ?sets larger than 30arcsec.From this comparison we ?nd that a scale height of 0.8kpc best ?ts the data.We then determine from this comparison a scaling for the model so that it represents the unnormalized data.Figure 10(left)shows this averaged cut along the minor axis.This ?g-ure shows the data (solid line)and the scaled model for z g =0.7(dashed red line),0.8(dashed blue line),0.9(dashed green line)kpc.We see that z g =0.8kpc is the best ?t to the data.

As a check on our scaling factor and our scale lengths Fig.10shows on the right a cut parallel to the major axis at a verti-cal o ?set of 30arcsec.The solid black line is the data and the colored lines are the scaled models with a changing scale length with h g =3.0kpc (dashed red line),h g =5.0kpc (dashed blue line)and h g =6.5kpc (dashed green line).This ?gure shows clearly that a scale length of 5kpc is the best ?t to the data.

P.Kamphuis et al.:Kinematics of di ?use ionized gas in the disk halo interface of NGC 891from Fabry-P′e rot observations

9

Fig.10.Normalized intensity cuts of integrated maps.Left:

along the minor axis.H α(solid line)),z g =0.7kpc (dashed red line),z g =0.8kpc (dashed blue line),z g =0.9kpc (dashed green line).Right:Parallel to the major axis at a vertical o ?set of 30arcsec.H α(solid line)),h g =3.0kpc (dashed red line),h g =5.0kpc (dashed blue line),h g =6.5kpc (dashed green line)5.4.Cube model

Having obtained the best ?ts for the images and the major axis PV-diagram we model a full data cube so we can obtain PV-diagrams at any height in the disk.We constructed two of these cubes based on the the best ?t of the major axis PV-diagram.These cubes are then binned in the same way as the data and scaled with the previously derived scaling factor.In one of these cubes the rotation curve is kept constant

throughout the vertical distribution of the cube (Model 3,see Table 2).The other cube model contains a vertical gradient for the rotation curve of -18.35km s ?1kpc ?1(Model G3,see Table 2).In this model the radial shape of the rotation curve is not changed.These cubes and their comparison to the data will be presented below.

6.Discussion

6.1.Kinematics in the plane

Figure 11shows a PV diagram of the H αemission along the major axis of the galaxy (|z |=0).This diagram bears the signature of solid body rotation instead of showing the strong di ?erential rotation of the HI.The simplest interpretation of this is that the disk of the galaxy is optically thick at |z |=0,so that the H αemission we see is mostly coming from the front edge of the disk.This is consistent with τH α=6.

Let us consider one ‘cut’through this diagram parallel to the velocity axis,at a radial o ?set of -1arcmin (Fig.12).Presuming that the H αemission emanates from gas which is in circular rotation,the H αemission at |25|km s ?1is at the very front of the disk.There is an absence of emission at lower velocities because the H αdisappears as we get to the front edge of the disk of the galaxy.As we descend in this diagram towards |175|km s ?1,at the same radial o ?set,the emission fades out.We interpret this as a result of increasing extinction due to dust in the plane.From our best ?t model,approximately 6.5magnitudes of extinction,along the line of sight to the center of the galaxy,are implied by this interpretation of the data;assuming that there is no extinction in the HI.

As we sample H αemission at larger radial o ?set we look closer to the line of nodes,and the velocities increase until

Fig.11.Color plot of the H αPV diagram along the major axis.For comparison the HI PV diagram on the major axis is over plotted at contour levels 3σ,6σand 9σ.

Fig.12.Normalized velocity line pro?les of the H α(Solid line)and HI(dashed line)on the major axis at a radial o ?set of -1ar-cmin.The straight lines indicate the 3σvalues for both obser-vations

we actually look at the line of nodes and the velocities do not rise anymore.Note though that due to the clumpiness of the emission sources the velocities can still decrease after this point.Alternatively,the H αemission may be con?ned to a thin annulus in the galaxy.This annulus would have to be in the outer parts of the galaxy,with little or no emission inside it.We consider such a distribution of the H αto be unlikely,especially in the view of the H αat higher |z |,as we shall discuss in section 6.2.

Figure 11clearly shows the dichotomy between the NE and

10P.Kamphuis et al.:Kinematics of di?use ionized gas in the disk halo interface of NGC891from Fabry-P′e rot observations SW discussed earlier(sect.4).If NGC891has spiral arms,the

asymmetry suggests that the Hαemission on the north side is

emanating from H II regions located on the outside of the spiral

arm,while to the south we are viewing the opposite arm from

the inside.This suggested morphology is also consistent with

the fact that the North-East side of the galaxy is approaching us,

while the South-West side is receding,since then the spiral arms

are trailing.From the ratio of emission between the NE and the

SW side along the along the major axis this morphology implies

an extra1.1magnitudes of extinction on the SW side due to the

spiral arm.

6.2.Kinematics at high z

Figures13,14and15show velocity cuts parallel to the major

axis at an o?set of24-33,46-65and66-104arcsec respectively.

The?rst thing that we notice from these?gures is that the

dichotomy in intensity is also clearly visible above the plane.In

fact,as we can see from Figs.14and15,above|z|～30there

is not enough emission on the SW side to say anything sensible

about the rotation of the gas.

Since dust absorption above the plane is likely to be negligi-

ble this fact suggests that the dichotomy is a real physical e?ect

and that star formation in the SW is less intense,assuming the

extra-planar gas is indeed brought up from the disk by a mecha-

nism related to star formation.

As an initial guess of the gradient,and to compare with the

observations of Heald et al.(2006),we performed envelope trac-ing on Fig.13,Fig.14and Fig.15.Envelope tracing basically?ts Gaussian pro?les,with a dispersion equal to the intrinsic disper-sion of the gas convolved with the instrumental dispersion,to the three points with the highest rotational velocity above3σ.The peak position of the?tted Gauss is then considered the rotational velocity.This method is not very trust worthy above the plane of the galaxy where the S/N can become low(see Fraternali et al. (2005))

The points obtained with this method are shown in Fig.16 (left).For comparison,Figure16(left)also shows the HI rotation curve on the major axis and the results of Heald et al.(2006).We see that in general our data is in agreement with their SPARSE-PAK observations.Since we have a full cube we can study the slope of the rotation curve in the inner parts.We?nd that above the plane the rotation curve rises less steeply with radius the fur-ther we get from the plane.The HI observations already hinted at this but due to the resolution this result could not be con?rmed. At every height we average the points obtained at radii larger than80arcsec.These points are shown in Fig.16(right).With these three points we?nd from envelope tracing a gradient of15±6.3km s?1kpc?1.

Figure13shows that the general slope of the diagram steep-ens compared to PV-diagram at the major axis.This is as we would expect since the gas is less obscured by the dust above the plane.Therefore,we can look farther into the galaxy and look at gas closer to the line of nodes.This steepening is also the reason why a thin annulus in the outer parts of the galaxy(See§6.1) is very unlikely.In such a distribution this steepening would not be possible unless the gas of the annulus would move inward as it rises above the plane.Such an e?ect seems highly unlikely.

If we compare the data to Model3we see that the steepening is not enough.Our model has much more gas at high velocities near the center of the galaxy.This lack of gas at the high veloci-ties in the center might still be an e?ect of the dust but could also indicate that the rotational velocities of the gas above the plane Fig.13.Color plot of the HαPV-diagram at26-34arcsec(1.2-1.6kpc)o?set from the major axis.Contours are at3σ.The white solid contour is the data,black contour is the best?t model (Model3,Table2),red contour is the best?t model with an assumed vertical gradient of16.5km s?1kpc?1in the rotation curve(Model G3),Table2.

not only lag compared to the disk but that the rotation curve rises less steep radially the higher we look above the plane.

A close inspection of Figure13shows us that there are two more places where the data deviate from the model.The model underestimates the intensities at low velocities and over-estimates them at high velocities.The lack of gas at high ve-locities at all radii con?rms the lagging rotation curve found by Fraternali et al.(2005)and Heald et al.(2006).If we draw a straight line through the lower part of the3σcontour of the data and and then draw a straight line through the same contour of Model3we can measure the lagging of the halo.In this way we?nd a di?erence between Model3and the data～18.75±6.3 km s?1at a vertical o?set of30arcsec(1.4kpc).

In the diagram that shows the gas at an o?set of60arcsec (Fig.14)we see that the slope of the emission becomes less steep compared to the slope at30arcsec.This is the continued e?ect of the rotation curve rising less steeply with radius the further we get from the plane.For this e?ect to be caused by dust the dust extinction would have to increase again which seems highly un-likely.

From Figure14we?nd a di?erence between Model3and the data,by comparing the3σcontours,of62.5±6.3km s?1. At this height we cannot be completely certain we are looking at the?at part of the rotation curve.Therefore,these e?ects could also be caused by radial redistribution of the gas.We consider it unlikely that such a redistribution completely causes the changes of the observed PV-diagram because intensity cuts parallel to the major axis only show a hint of such an e?ect and only at the East

P.Kamphuis et al.:Kinematics of di?use ionized gas in the disk halo interface of NGC891from Fabry-P′e rot observations11

Fig.14.Same as Fig.

13except now for the bin48-67arcsec

(2.2-3.1kpc)o?set from the major axis.

Fig.15.Same as Fig.13except now for the bin68-107arcsec (3.2-4.9kpc)o?set from the major axis.Fig.16.(Left)Results of employing envelope tracing to the data. Blue(pluses):HI on the major axis(Fraternali et al.,2005),red: points found by Heald et al.(2006),at vertical o?sets～30arc-sec(squares),～50arcsec(triangles)and～80arcsec(dia-monds).Black:our data at vertical o?sets of30arcsec(squares), 40arcsec(crosses),58arcsec(triangles)and88arcsec(dia-monds).(Right)The average rotational velocity obtained with envelope tracing at a vertical o?set of30,40,58and88arcsec (1.4,1.9,2.7and4.1kpc)for our data(squares)and average points as obtained by Heald et al.(2006)at vertical o?sets～30, 50,80arcsec(1.4,2.4,3.7kpc)(triangles).

side of the galaxy,as shown by Heald et al.(2006)(their Fig.7), while the West side is the brighter side of the halo.

Figure15shows the gas at90arcsec o?set from the major axis.The emission of the di?use gas at this height is very low and we had too compare the1σcontours of the model and the data.Therefore conclusions drawn from this plot are considered to be no more than indicative.At this vertical o?set the e?ects observed at a60arcsec o?set https://www.sodocs.net/doc/8c303358.html,paring the highest velocity of the1σcontour at this height with Model3we ob-serve a di?erence of81.25±12.5km s?1.

When we assume that the gradient starts on the major axis we?nd the slope of the gradient to be～18.8±6.3km s?1when we?t the points at30,60and90arcsec(1.4,2.7and4.1kpc).

After determining the gradient of the lag we constructed a model(Model G3,see Table2)in which the rotation curve is scaled down at higher|z|by subtracting at every vertical step in the model|z|×18.8km s?1,with|z|in kpc,from the rota-tion curve as obtained from the HI.The vertical step size in the model was49pc(1.05arcsec).Model G3is plotted in Figs.13, 14and15as the red contours.We see that gas is still missing at various places in the diagram but that the maximum and mini-mum velocities are approximately the same for the data as this model at the3σcontour.Thus con?rming that there is a gradient of-18.8±6.3km s?1kpc?1in the observations.The explanation for the missing gas remains the same as before since we did not change the shape of the rotation curve.

Another way to look at the kinematics at higher|z|is by constructing PV diagrams along the minor axis and parallel to the minor axis at some radial o?set.To optimize the informa-tion in the diagrams we normalized them by dividing every line pro?le by it’s maximum.Figure17is an example of such a PV-diagram.This PV-diagram is constructed by looking through the cube at a radial o?set of150arcsec and is a cut parallel to the minor axis.Overlaid on the color scale are the3,6,9σcontours of the HI.Looking at this plot the?rst thing we see is that the

12P.Kamphuis et al.:Kinematics of di ?use ionized gas in the disk halo interface of NGC 891from Fabry-P′e rot

observations

Fig.17.Normalized color plot of the H αPV-diagram at a radial

o ?set of 150arcsec parallel to the minor axis and overlaid with contours of HI at 3σ,6σand 9σ

.

Fig.18.Same

as 17but now at a radial o ?set of 75arcsec.

Fig.19.Same as 17but now at the minor axis position.HI is much more extended vertically than the H α.This is partly due to beam smearing but not completely.If we look at the H αat low mean velocity (～|140|km s ?1)we see that in the plane of the galaxy (e.g.0o ?set)the maximum of the emission lies at this low mean velocity.Moving away from the plane the max-imum of the emission ?rst rises to higher mean velocities and then drops again.The initial rise is caused by diminishing dust attenuation.As we move further from the plane the maximum of the emission drops to lower mean velocities again.This drop is caused by the lower rotational velocities at higher |z |.The H αis much less extended than the HI,in velocity as well as ver-tical size (z EM =0.5kpc (Dettmar,1990),the ionized gas scale height is twice this,z HI =2.3kpc (T.Oosterloo,https://www.sodocs.net/doc/8c303358.html,munica-tion)).Considering the sensitivity of both observations it could well be that our H αobservations are just not sensitive enough to observe all the ionized gas in the galaxy.We also plot PV diagrams parallel to the minor axis at a o ?set of 75arcsec and on the minor axis itself,Figures 18and 19respectively.In the ?gure at 75arcsec o ?set from the minor axis we see the same behavior as at 150arcsec o ?set,only here the rise and drop in mean velocities is much more extreme.We also see that in this diagram the mean velocity at the highest o ?set from the plane drops back towards systemic.This di ?erence is caused by the rotation curve which rises less steep the further we look above the plane.Looking at the diagram which is a cut along the mi-nor axis of the galaxy (Fig.19)we see that here the maximum of the H αemission lies one channel below systemic velocity at almost all the o ?sets from the plane.This o ?set is about 18km s ?1which is larger than the error in the wavelength calibration (e.g.,6km s ?1).We are con?dent this o ?set is not an error in our velocity scale.In principle we could check this by comparing the ?at rotation speeds on the North side to those on the South side but we think such a check is unreliable due to the e ?ects of dust

P.Kamphuis et al.:Kinematics of di?use ionized gas in the disk halo interface of NGC891from Fabry-P′e rot observations13

on the South side.

The?at shape in Figure19is as expected;the o?set from systemic is unexpected.We realize that our central position of the galaxy is somewhat to the south from the central position generally used in kinematical studies,but notice that shifting the central position to the north would further remove us from the kinematical center of the Hα.Also our kinematical center and the center used in this paper would lie in the same resolution el-ement of the HI observations.We note that at a vertical o?set of ～60arcsec the maximum seems to be displaced more from the systemic velocity.This is a real e?ect and is not caused by our way of binning the data.Whether this deviation is important for understanding the general dynamics of the halo remains unclear.

7.Summary

We present Fabry-P′e rot Hαmeasurements of the edge-on galaxy NGC891.This is the?rst time kinematical data for the Hαare presented for the whole of NGC891.

In our observations we can clearly see Hαemission above and below the plane of NGC891.This vertical extent is already visible in the separate channel maps and becomes even more obvious in a velocity integrated map.

This integrated velocity map shows a clear contrast between the distribution of the Hαon the North-East and the South-West side of the galaxy.This dichotomy is not restricted to the plane of the galaxy but is also clearly visible above the plane.Since dust absorption is negligible above the plane it is likely that this dichotomy is a real physical e?ect.Assuming that the halo gas is brought up from the plane by a SFR related mechanism,this implies that the SFR on the South-West side of the galaxy is much lower than on the North-East side of the galaxy.

For the interpretation of the kinematics of the extra-planar gas we constructed several3-D models of an exponential disk rotating with a rotation curve derived from the HI data (Fraternali et al.,2005).Included in the models is a uniform dust layer of given optical depth distributed exponentially in radius and height and a truncation radius.

We started with models that have the same scale length for the dust disk as the Hαdisk(h g=h d=5kpc).We?nd that such models generate too much intensity at large radii and high velocities when we compare them to the data.To overcome this problem we modeled the galaxy with a dust scale length of 8.1kpc,as derived by Xilouris et al.(1998)from observations in the V-band.The longer scale length of the dust reduces the intensity of the gas at large radii and high velocities.This also provides us with a upper limit scale length of the ionized gas of6.5kpc(Model1.1).Longer scale lengths would reintroduce the too high intensities found in the?rst models.A lower limit is found for a model with a scale length of2.5kpc(Model2.2). Models with even shorter scale lengths do not produce enough intensity at large radii.Better constrains could be obtained if the truncation radius of the dust disk would be known.

When we?t models in this range to the PV-diagram of the major axis we?nd that the best?t is a model with a central attenuation ofτHα=6,a cut o?radius R max=14kpc and a scale length and height of5.0kpc and0.8kpc respectively (Model3).By comparing PV-diagrams above the plane to the models kinematical information about the galaxy is extracted from the data.We con?rm the lagging of the halo,as found by Fraternali et al.(2005)and Heald et al.(2006),and determine that this lagging occurs with gradient of～18.8±6.3km s?1 kpc?1.

In the PV-diagrams we also see that compared to the models the distribution of the Hαis displaced to larger radii or lower rotational velocities.This e?ect increases as we look higher above the plane.This means that the higher we look above the plane,the less steep the rotation curve rises.We can con?rm this by comparing three cuts through the cube along and parallel to the minor axis.After normalizing these PV-diagrams we can clearly see that the Hαat a distance of75arcsec from the center has a larger gradient than the Hαat150arcsec from the center. Acknowledgements.We wish to thank the referee R.Rand for many useful com-ments,F.Fraternali for providing the HI rotation curve,T.Oosterloo for provid-ing the HI data on NGC891,G.Heald and R.Rand for providing their Hαrotation points and a calibrated Hαimage,M.Potter for providing the DSS posi-tions for the stars used for the astrometry,and R.Sancisi for insightful comments and discussion on the paper.

References

Barnab`e,M.,Ciotti,L.,Fraternali,F.,&Sancisi,R.2006,A&A,446,61 Bland,J.&Tully,R.B.1989,AJ,98,723

Bregman,J.N.1980,ApJ,236,577

Breitschwerdt,D.&Schmutzler,T.1999,A&A,347,650

Breitschwerdt,D.,V oelk,H.J.,&McKenzie,J.F.1991,A&A,245,79 Collins,J.A.,Benjamin,R.A.,&Rand,R.J.2002,ApJ,578,98

Dahlem,M.,Dettmar,R.-J.,&Hummel,E.1994,A&A,290,384

de Avillez,M.A.&Breitschwerdt,D.2005,A&A,436,585

Dettmar,R.-J.1990,A&A,232,L15

Dettmar,R.J.1992,Fundamentals of Cosmic Physics,15,143

Fraternali,F.&Binney,J.J.2006,MNRAS,366,449

Fraternali,F.,Oosterloo,T.A.,Sancisi,R.,&Swaters,R.2005,in ASP Conf.

Ser.331:Extra-Planar Gas,239–+

Heald,G.H.,Rand,R.J.,Benjamin,R.A.,&Bershady,M.A.2006,ApJ,647, 1018

Hoopes,C.G.,Walterbos,R.A.M.,&Rand,R.J.1999,ApJ,522,669 Howk,J.C.&Savage,B.D.1997,AJ,114,2463

Hummel,E.,Dahlem,M.,van der Hulst,J.M.,&Sukumar,S.1991,A&A,246, 10

Jones,D.H.,Shopbell,P.L.,&Bland-Hawthorn,J.2002,MNRAS,329,759 Keppel,J.W.,Dettmar,R.-J.,Gallagher,J.S.,&Roberts,M.S.1991,ApJ,374, 507

Koopmann,R.A.,Haynes,M.P.,&Catinella,B.2006,AJ,131,716

Miller,S.T.&Veilleux,S.2003,ApJS,148,383

Norman,C.A.&Ikeuchi,S.1989,ApJ,345,372

Pildis,R.A.,Bregman,J.N.,&Schombert,J.M.1994a,ApJ,427,160 Pildis,R.A.,Bregman,J.N.,&Schombert,J.M.1994b,ApJ,423,190 Rand,R.J.1996,ApJ,462,712

Rand,R.J.1997,ApJ,474,129

Rand,R.J.,Kulkarni,S.R.,&Hester,J.J.1990,ApJ,352,L1

Rand,R.J.,Kulkarni,S.R.,&Hester,J.J.1992,ApJ,396,97

Reynolds,R.J.1990,in IAU Symp.139:The Galactic and Extragalactic Background Radiation,ed.S.Bowyer&C.Leinert,157–169

Rossa,J.&Dettmar,R.-J.2003,A&A,406,505

Shapiro,P.R.&Field,G.B.1976,ApJ,205,762

Swaters,R.A.,Sancisi,R.,&van der Hulst,J.M.1997,ApJ,491,140

van der Kruit,P.C.&Searle,L.1981,A&A,95,116

Xilouris,E.M.,Alton,P.B.,Davies,J.I.,et al.1998,A&A,331,894

50万吨年煤气化生产工艺

咸阳职业技术学院生化工程系毕业论文（设计） 50wt/年煤气化工艺设计 1.引言 煤是由古代植物转变而来的大分子有机化合物。我国煤炭储量丰富，分布面广，品种齐全。据中国第二次煤田预测资料，埋深在1000m以浅的煤炭总资源量为2.6万亿t。其中大别山—秦岭—昆仑山一线以北地区资源量约2.45万亿t，占全国总资源量的94%；其余的广大地区仅占6%左右。其中新疆、内蒙古、山西和陕西等四省区占全国资源总量的81.3%，东北三省占 1.6%，华东七省占2.8%，江南九省占1.6%。 煤气化是煤炭的一个热化学加工过程，它是以煤或煤焦原料，以氧气（空气或富氧）、水蒸气或氢气等作气化剂，在高温条件下通过化学反应将煤或煤焦中的可燃部分转化为可燃性的气体的过程。气化时所得的可燃性气体称为煤气，所用的设备称为煤气发生炉。 煤气化技术开发较早，在20世纪20年代，世界上就有了常压固定层煤气发生炉。20世纪30年代至50年代，用于煤气化的加压固定床鲁奇炉、常压温克勒沸腾炉和常压气流床K-T炉先后实现了工业化，这批煤气化炉型一般称为第一代煤气化技术。第二代煤气化技术开发始于20世纪60年代，由于当时国际上石油和天然气资源开采及利用于制取合成气技术进步很快，大大降低了制造合成

气的投资和生产成本，导致世界上制取合成气的原料转向了天然气和石油为主，使煤气化新技术开发的进程受阻，20世纪70年代全球出现石油危机后，又促进了煤气化新技术开发工作的进程，到20世纪80年代，开发的煤气化新技术，有的实现了工业化，有的完成了示范厂的试验，具有代表性的炉型有德士古加压水煤浆气化炉、熔渣鲁奇炉、高温温克勒炉（ETIW）及干粉煤加压气化炉等。 近年来国外煤气化技术的开发和发展，有倾向于以煤粉和水煤浆为原料、以高温高压操作的气流床和流化床炉型为主的趋势。 2.煤气化过程 2.1煤气化的定义 煤与氧气或（富氧空气）发生不完全燃烧反应，生成一氧化碳和氢气的过程称为煤气化。煤气化按气化剂可分为水蒸气气化、空气（富氧空气）气化、空气—水蒸气气化和氢气气化；按操作压力分为：常压气化和加压气化。由于加压气化具有生产强度高，对燃气输配和后续化学加工具有明显的经济性等优点。所以近代气化技术十分注重加压气化技术的开发。目前，将气化压力在P＞2MPa 情况下的气化，统称为加压气化技术；按残渣排出形式可分为固态排渣和液态排渣。气化残渣以固体形态排出气化炉外的称固态排渣。气化残渣以液态方式排出经急冷后变成熔渣排出气化炉外的称液态排渣；按加热方式、原料粒度、汽化程度等还有多种分类方法。常用的是按气化炉内煤料与气化剂的接触方式区分，主要有固定床气化、流化床气化、气流床气化和熔浴床床气化。 2.2 主要反应 煤的气化包括煤的热解和煤的气化反应两部分。煤在加热时会发生一系列的物理变化和化学变化。气化炉中的气化反应，是一个十分复杂的体系，这里所讨论的气化反应主要是指煤中的碳与气化剂中的氧气、水蒸汽和氢气的反应，也包括碳与反应产物之间进行的反应。 习惯上将气化反应分为三种类型：碳—氧之间的反应、水蒸汽分解反应和甲烷生产反应。 2.2.1碳—氧间的反应 碳与氧之间的反应有： C+O2=CO2（1）

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煤化工工艺流程 典型的焦化厂一般有备煤车间、炼焦车间、回收车间、焦油加工车间、苯加工车间、脱硫车间和废水处理车间等。 焦化厂生产工艺流程 1.备煤与洗煤 原煤一般含有较高的灰分和硫分，洗选加工的目的是降低煤的灰分，使混杂在煤中的矸石、煤矸共生的夹矸煤与煤炭按照其相对密度、外形及物理性状方面的差异加以分离，同时，降低原煤中的无机硫含量，以满足不同用户对煤炭质量的指标要求。 由于洗煤厂动力设备繁多，控制过程复杂，用分散型控制系统DCS改造传统洗煤工艺，这对于提高洗煤过程的自动化，减轻工人的劳动强度，提高产品产量和质量以及安全生产都具有重要意义。

洗煤厂工艺流程图 控制方案 洗煤厂电机顺序启动/停止控制流程框图 联锁/解锁方案：在运行解锁状态下，允许对每台设备进行单独启动或停止；当设置为联锁状态时，按下启动按纽，设备顺序启动，后一设备的启动以前一设备的启动为条件（设备间的延时启动时间可设置），如果前一设备未启动成功，后一设备不能启动，按停止键，则设备顺序停止，在运行过程中，如果其中一台设备故障停止，例如设备2停止，则系统会把设备3和设备4停止，但设备1保持运行。

2.焦炉与冷鼓 以100万吨/年-144孔-双炉-4集气管-1个大回流炼焦装置为例，其工艺流程简介如下：

100万吨/年焦炉_冷鼓工艺流程图 控制方案 典型的炼焦过程可分为焦炉和冷鼓两个工段。这两个工段既有分工又相互联系，两者在地理位置上也距离较远，为了避免仪表的长距离走线，设置一个冷鼓远程站及给水远程站，以使仪表线能现场就近进入DCS控制柜，更重要的是，在集气管压力调节中，两个站之间有着重要的联锁及其排队关系，这样的网络结构形式便于可以实现复杂的控制算法。

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，除去煤气中的CO2和H2S。净化后的煤气分为两大部分，一部分去甲醇合成系统，合成气再经压缩机加压至5.3MPa，进入甲醇反应器生成粗甲醇，粗甲醇再送入甲醇精馏系统，制得精甲醇产品存入贮罐；另一部分去净煤气变换装置。合成甲醇尾气及变换气混合后，与剩余部分出低温甲醇洗净煤气混合后，进入煤气冷却干燥装置，将露点降至-25℃后，作为合格城市煤气经长输管线送往各用气城市。生产过程中产生的煤气水进入煤气水分离装置，分离出其中的焦油、中油。分离后煤气水去酚回收和氨回收，回收酚氨后的煤气水经污水生化处理装置处理，达标后排放。低温甲醇洗净化装置排出的H2S到硫回收装置回收硫。空分装置提供气化用氧气和全厂公用氮气。仪表空压站为全厂仪表提供合格的仪表空气。 小于5mm粉煤，作为锅炉燃料，送至锅炉装置生产蒸汽，产出的蒸汽一部分供工艺装置用汽，一部分供发电站发电。 3、主要装置工艺流程 3.1备煤装置工艺流程简述 备煤工艺流程分为三个系统： （1）原煤破碎筛分贮存系统，汽运原煤至受煤坑经1#、2#、3#皮带转载至筛分楼、经节肢筛、破碎机、驰张筛加工后，6~50mm块煤由7#皮带运至块煤仓，小于6mm末煤经6#、11#皮带近至末煤仓。 （2）最终筛分系统：块煤仓内块煤经8#、9#皮带运至最终筛分楼驰张筛进行检查性筛分。大于6mm块煤经10#皮带送至200#煤斗，筛下小于6mm末煤经14#皮带送至缓冲仓。 （3）电厂上煤系统：末煤仓内末煤经12#、13#皮带转至5#点后经16#皮

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煤气化工艺资料

煤化工是以煤为原料，经过化学加工使煤转化为气体，液体，固体燃料以及化学品的过程，生产出各种化工产品的工业。 煤化工包括煤的一次化学加工、二次化学加工和深度化学加工。煤的气化、液化、焦化，煤的合成气化工、焦油化工和电石乙炔化工等，都属于煤化工的范围。而煤的气化、液化、焦化（干馏）又是煤化工中非常重要的三种加工方式。 煤的气化、液化和焦化概要流程图 一.煤炭气化

煤炭气化是指煤在特定的设备内，在一定温度及压力下使煤中有机质与气化剂（如蒸汽/空气或氧气等）发生一系列化学反应，将固体煤转化为含有CO、H2、CH4等可燃气体和CO2、N2等非可燃气体的过程。 煤的气化的一般流程图 煤炭气化包含一系列物理、化学变化。而化学变化是煤炭气化的主要方式，主要的化学反应有： 1、水蒸气转化反应C+H2O=CO+H2 2、水煤气变换反应CO+ H2O =CO2+H2 3、部分氧化反应C+0.5 O2=CO 4、完全氧化（燃烧）反应C+O2=CO2 5、甲烷化反应CO+2H2=CH4 6、Boudouard反应C+CO2=2CO 其中1、6为放热反应，2、3、4、5为吸热反应。 煤炭气化时，必须具备三个条件，即气化炉、气化剂、供给热量，三者缺一不可。 煤炭气化按气化炉内煤料与气化剂的接触方式区分，主要有： 1) 固定床气化：在气化过程中，煤由气化炉顶部加入，气化剂由气化炉底部加入，煤料与气化剂逆流接触，相对于气体的上升速度而言，煤料下降速度很慢，甚至可视为固定不动，因此称之为固定床气化；而实际上，煤料在气化过程中是以很慢的速度向下移动的，比

较准确的称其为移动床气化。 2) 流化床气化：它是以粒度为0-10mm的小颗粒煤为气化原料，在气化炉内使其悬浮分散在垂直上升的气流中，煤粒在沸腾状态进行气化反应，从而使得煤料层内温度均一，易于控制，提高气化效率。 3) 气流床气化。它是一种并流气化，用气化剂将粒度为100um以下的煤粉带入气化炉内，也可将煤粉先制成水煤浆，然后用泵打入气化炉内。煤料在高于其灰熔点的温度下与气化剂发生燃烧反应和气化反应，灰渣以液态形式排出气化炉。 4) 熔浴床气化。它是将粉煤和气化剂以切线方向高速喷入一温度较高且高度稳定的熔池内，把一部分动能传给熔渣，使池内熔融物做螺旋状的旋转运动并气化。目前此气化工艺已不再发展。 以上均为地面气化，还有地下气化工艺。 根据采用的气化剂和煤气成分的不同，可以把煤气分为四类：1.以空气作为气化剂的空气煤气；2.以空气及蒸汽作为气化剂的混合煤气，也被称为发生炉煤气；3.以水蒸气和氧气作为气化剂的水煤气；4.以蒸汽及空气作为气化剂的半水煤气，也可是空气煤气和水煤气的混合气。 几种重要的煤气化技术及其技术性能比较 1.Lurgi炉固定床加压气化法对煤质要求较高，只能用弱粘结块煤，冷煤气效率最高，气化强度高，粗煤气中甲烷含量较高，但净化系统复杂，焦油、污水等处理困难。 鲁奇煤气化工艺流程图

煤气化制甲醇工艺流程

煤气化制甲醇工艺流程 煤气化制甲醇工艺流程简述 1）气化 a）煤浆制备 由煤运系统送来的原料煤**t/h（干基）（<25mm）或焦送至煤贮斗，经称重给料机控制输送量送入棒磨机，加入一定量的水，物料在棒磨机中进行湿法磨煤。为了控制煤浆粘度及保持煤浆的稳定性加入添加剂，为了调整煤浆的PH值，加入碱液。 出棒磨机的煤浆浓度约65%，排入磨煤机出口槽，经出口槽泵加压后送至气化工段煤浆槽。 煤浆制备首先要将煤焦磨细，再制备成约65%的煤浆。磨煤采用湿法，可防止粉尘飞扬，环境好。 用于煤浆气化的磨机现在有两种，棒磨机与球磨机；棒磨机与球磨机相比，棒磨机磨出的煤浆粒度均匀，筛下物少。 煤浆制备能力需和气化炉相匹配，本项目拟选用三台棒磨机，单台磨机处理干煤量43～53t/h，可满足60万t/a甲醇的需要。 为了降低煤浆粘度，使煤浆具有良好的流动性，需加入添加剂，初步选择木质磺酸类添加剂。 煤浆气化需调整浆的PH值在6～8，可用稀氨水或碱液，稀氨水易挥发出氨，氨气对人体有害，污染空气，故本项目拟采用碱液调整煤浆的PH值，碱液初步采用42％的浓度。 为了节约水源，净化排出的含少量甲醇的废水及甲醇精馏废水均可作为磨浆水。 b）气化 在本工段，煤浆与氧进行部分氧化反应制得粗合成气。 煤浆由煤浆槽经煤浆加压泵加压后连同空分送来的高压氧通过烧咀进入气化炉，在气化炉中煤浆与氧发生如下主要反应： CmHnSr+m/2O2—→mCO+（n/2-r）H2+rH2S CO+H2O—→H2+CO2 反应在6.5MPa（G）、1350～1400℃下进行。 气化反应在气化炉反应段瞬间完成，生成CO、H2、CO2、H2O和少量CH4、H2S等气体。 离开气化炉反应段的热气体和熔渣进入激冷室水浴，被水淬冷后温度降低并被水蒸汽饱和后出气化炉；气体经文丘里洗涤器、碳洗塔洗涤除尘冷却后送至变换工段。 气化炉反应中生成的熔渣进入激冷室水浴后被分离出来，排入锁斗，定时排入渣池，由扒渣机捞出后装车外运。 气化炉及碳洗塔等排出的洗涤水（称为黑水）送往灰水处理。 c）灰水处理 本工段将气化来的黑水进行渣水分离，处理后的水循环使用。 从气化炉和碳洗塔排出的高温黑水分别进入各自的高压闪蒸器，经高压闪蒸浓缩后的黑水混合，经低压、两级真空闪蒸被浓缩后进入澄清槽，水中加入絮凝剂使其加速沉淀。澄清槽底部的细渣浆经泵抽出送往过滤机给料槽，经由过滤机给料泵加压后送至真空过滤机脱水，渣饼由汽车拉出厂外。 闪蒸出的高压气体经过灰水加热器回收热量之后，通过气液分离器分离掉冷凝液，然后进入变换工段汽提塔。

煤气化工艺流程简述

煤气化工艺流程简述 1）气化 a）煤浆制备 由煤运系统送来的原料煤**t/h（干基）（<25mm）或焦送至煤贮斗，经称重给料机控制输送量送入棒磨机，加入一定量的水，物料在棒磨机中进行湿法磨煤。为了控制煤浆粘度及保持煤浆的稳定性加入添加剂，为了调整煤浆的PH值，加入碱液。 出棒磨机的煤浆浓度约65%，排入磨煤机出口槽，经出口槽泵加压后送至气化工段煤浆槽。 煤浆制备首先要将煤焦磨细，再制备成约65%的煤浆。磨煤采用湿法，可防止粉尘飞扬，环境好。 用于煤浆气化的磨机现在有两种，棒磨机与球磨机；棒磨机与球磨机相比，棒磨机磨出的煤浆粒度均匀，筛下物少。 煤浆制备能力需和气化炉相匹配，本项目拟选用三台棒磨机，单台磨机处理干煤量43～53t/h，可满足60万t/a甲醇的需要。 为了降低煤浆粘度，使煤浆具有良好的流动性，需加入添加剂，初步选择木质磺酸类添加剂。 煤浆气化需调整浆的PH值在6～8，可用稀氨水或碱液，稀氨水易挥发出氨，氨气对人体有害，污染空气，故本项目拟采用碱液调整煤浆的PH值，碱液初步采用42％的浓度。 为了节约水源，净化排出的含少量甲醇的废水及甲醇精馏废水均可作为磨浆水。 b）气化 在本工段，煤浆与氧进行部分氧化反应制得粗合成气。 煤浆由煤浆槽经煤浆加压泵加压后连同空分送来的高压氧通过烧咀进入气化炉，在气化炉中煤浆与氧发生如下主要反应： CmHnSr+m/2O2—→mCO+（n/2-r）H2+rH2S CO+H2O—→H2+CO2 反应在6.5MPa（G）、1350～1400℃下进行。 气化反应在气化炉反应段瞬间完成，生成CO、H2、CO2、H2O和少量CH4、H2S等气体。 离开气化炉反应段的热气体和熔渣进入激冷室水浴，被水淬冷后温度降低并被水蒸汽饱和后出气化炉；气体经文丘里洗涤器、碳洗塔洗涤除尘冷却后送至变换工段。

煤气化制甲醇工艺流程

煤气化制甲醇工艺流程
煤气化制甲醇工艺流程 2008-11-08 10:11 1)气化 a)煤浆制备 由煤运系统送来的原料煤**t/h(干基)(<25mm)或焦送至煤贮斗，经称重给料机控 制输送量送入棒磨机，加入一定量的水，物料在棒磨机中进行湿法磨煤。为了控制煤 浆粘度及保持煤浆的稳定性加入添加剂，为了调整煤浆的 PH 值，加入碱液。
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出棒磨机的煤浆浓度约 65%，排入磨煤机出口槽，经出口槽泵加压后送至气化工 段煤浆槽。 煤浆制备首先要将煤焦磨细，再制备成约 65%的煤浆。磨煤采用湿法，可防止粉 尘飞扬，环境好。 用于煤浆气化的磨机现在有两种，棒磨机与球磨机;棒磨机与球磨机相比，棒磨机 磨出的煤浆粒度均匀，筛下物少。
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煤浆制备能力需和气化炉相匹配，本项目拟选用三台棒磨机，单台磨机处理干煤 量 43,53t/h，可满足 60 万 t/a 甲醇的需要。
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为了降低煤浆粘度，使煤浆具有良好的流动性，需加入添加剂，初步选择木质磺 酸类添加剂。
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煤浆气化需调整浆的 PH 值在 6,8，可用稀氨水或碱液，稀氨水易挥发出氨，氨气 对人体有害，污染空气，故本项目拟采用碱液调整煤浆的 PH 值，碱液初步采用 42,的 浓度。
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为了节约水源，净化排出的含少量甲醇的废水及甲醇精馏废水均可作为磨浆水。 b)气化 在本工段，煤浆与氧进行部分氧化反应制得粗合成气。 煤浆由煤浆槽经煤浆加压泵加压后连同空分送来的高压氧通过烧咀进入气化炉， 在气化炉中煤浆与氧发生如下主要反应:
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CmHnSr+m/2O2—?mCO+(n/2-r)H2+rH2S CO+H2O—?H2+CO2 反应在 6.5MPa(G)、1350,1400?下进行。 气化反应在气化炉反应段瞬间完成，生成 CO、H2、CO2、H2O 和少量 CH4、H2S 等气 体。 离开气化炉反应段的热气体和熔渣进入激冷室水浴，被水淬冷后温度降低并被水 蒸汽饱和后出气化炉;气体经文丘里洗涤器、碳洗塔洗涤除尘冷却后送至变换工段。
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气化炉反应中生成的熔渣进入激冷室水浴后被分离出来，排入锁斗，定时排入渣 池，由扒渣机捞出后装车外运。 气化炉及碳洗塔等排出的洗涤水(称为黑水)送往灰水处理。 c)灰水处理 本工段将气化来的黑水进行渣水分离，处理后的水循环使用。 从气化炉和碳洗塔排出的高温黑水分别进入各自的高压闪蒸器，经高压闪蒸浓缩 后的黑水混合，经低压、两级真空闪蒸被浓缩后进入澄清槽，水中加入絮凝剂使其加
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煤气化工艺流程(德士古气化炉)

煤气化工艺流程（德士古气化炉）
煤气化工艺流程 一、 制浆系统 1、系统图 2、工艺叙述 由煤贮运系统来的小于 10mm 的碎煤进入煤贮斗后， 经煤称量给料机称量送入磨 机。 30%的添加剂由人工送至添加剂溶解槽中溶解成 3%的水溶液， 由添加剂溶解槽 泵送至添加剂槽中贮存。 并由添加剂计量泵送至磨机中。在添加剂槽底部设有蒸汽盘 管,在冬季维持添加剂温度在 20--30?，以防止冻结。
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工艺水由研磨水泵经磨机给水阀来控制送至磨机。煤、工艺水和添加剂一同送入 磨机中研磨成一定粒度分布的浓度约 59%-62%合格的水煤浆。水煤浆经滚筒筛滤去 3mm 以上的大颗粒后溢流至磨机出料槽中，由磨机出料槽泵送至煤浆槽。磨机出料槽和煤 浆槽均设有搅拌器，使煤浆始终处于均匀悬浮状态。 二、气化炉系统 1、系统图 2、工艺叙述 来自煤浆槽浓度为 59%-62%的煤浆，由煤浆给料泵加压，投料前经煤浆循环阀循 环至煤浆槽。投料后经煤浆切断阀送至德士古烧嘴的内环隙。
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空分装置送来的纯度为 99.6%的氧气经氧气缓冲罐，控制氧气压力为 6.0~6.2MPa，在准备投料前打开氧气手动阀，由氧气调节阀控制氧气流量经氧气放空 阀送至氧气消音器放空。投料后由氧气调节阀控制氧气经氧气上、下游切断阀送入德 士古烧嘴。
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水煤浆和氧气在德士古烧嘴中充分混合雾化后进入气化炉的燃烧室中，在约 4.0MPa、1300?条件下进行气化反应。生成以 CO 和 H 为有效成份的粗合成气。粗 25PCzVD7HxA 合成气和熔融态灰渣一起向下，经过均匀分布激冷水的激冷环沿下降管进入激冷 室的水浴中。大部分的熔渣经冷却固化后，落入激冷室底部。粗合成气从下降管和导 气管的环隙上升，出激冷室去洗涤塔。在激冷室合成气出口处设有工艺冷凝液冲洗 水，以防止灰渣在出口管累积堵塞，并增湿粗合成气。由冷凝液冲洗水调 jLBHrnAILg 3 节阀控制冲洗水量为 23m/h。 激冷水经激冷水过滤器滤去可能堵塞激冷环的大颗粒，送入位于下降管上部的激 冷环。激冷水呈螺旋状沿下降管壁流下进入激冷室。
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激冷室底部黑水，经黑水排放阀送入黑水处理系统，激冷室液位控制在 50--55%。在开车期间，黑水经黑水开工排放阀排向真空闪蒸罐。
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在气化炉预热期间，激冷室出口气体由开工抽引器排入大气。开工抽引器底部通 入蒸汽，通过调节预热烧嘴风门和抽引蒸汽量来控制气化炉的真空度，气化炉配备了 预热烧嘴。
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三、合成气洗涤系统 1、系统图 2、工艺叙述 从激冷水浴出来饱和了水汽的合成气进入文丘里洗涤器，在这里与激冷水泵 送出的黑水混合，使合成气夹带的固体颗粒完全湿润，以便在洗涤塔内能快速除 去。
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煤气化工艺流程德士古气化炉

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德士古煤气化工艺烧嘴的浅议 王润斌高级技工助理工程师 （鄂尔多斯金诚泰煤化工气化车间2011-9-5） （关键词：煤气化工艺烧嘴） 概述 “我国石油和化学工业在快速发展的同时，正面临着资源、能源和环境等多重压力”。由于我国石油和天然气短缺，煤炭相对丰富的资源特征，加之国际油价的持续高位运行状态，煤炭在我国的能源和化工的未来发展中所处的地位会变得越来越重要。 目前，煤炭在我国的能源消费比重不断加大，用于发电和工业锅炉及窑炉的比例大约为70%左右，其余主要是作为化工原料及民用生活。随着煤化工技术的不断发展，煤炭作为化工原料的比重将会得到不断的提高。 传统的煤化工特点是高能耗、高排放、高污染、低效益，即通常所说的“三高一低”。随着科技的不断进步，新型的煤气化技术得到了快速的发展，煤炭作为化工原料的重要性得到了普遍的认可。煤化工目前采用的方法主要有三个途径：煤的焦化、煤的气化、煤的液化。由于最终产品的不同，三种途径均有存在的市场。煤焦化的直接产品主要有焦炭、煤焦油及焦炉气，煤气化的直接产品主要有合成气、一氧化碳和氢气，煤液化后可直接得到液体燃料。 煤焦化产业相对比较成熟，煤液化存在直接液化和间接液化两种方法，由于该技术的成熟程度和投资等原因，制约了其产业化和规

模化的进一步发展。随着煤气化技术的不断成熟，特别是加压气化方法的逐步完善和下游产品的多样化，煤气化已成为我国目前煤化工的重中之重。 煤气化所产生的合成气，成为氮肥（主要是尿素）、甲醇、二甲醚、醋酸等过去主要依赖石油化工产品的主要原料，也成为国内目前煤化工所上的主要项目。煤气化除了投资比较小的常压固定床以外，粉煤加压气化（以壳牌和GSP为主要代表）、水煤浆加压气化（以德士古为主要代表）成为众多厂家引进国外节能环保的主要首选技术。国内具有自主知识产权的煤气化技术还有：①粉煤加压气化：西安热工院的干煤粉加压气化技术、陕西联合能源的灰粘聚流化床粉煤气化技术、山西煤化所的灰熔聚流化床粉煤气化技术、北京航天万源的航天炉粉煤气化技术等。②水煤浆加压气化技术：华东理工大学的四对冲烧嘴技术、北京达立科的分级气化技术、西北化工研究院的多元料浆（主要成份是水煤浆）气化技术等。 本作者近年来一直从事于水煤浆气化的工艺及设备作，水煤浆 加压气化装置（包括引进装置和国产化装置）是目前国内广泛使用的煤加压气化技术（占到国内煤加压气化装置的75%以上），气化后得到的合成气主要用于合成氨、尿素、甲醇、醋酸等的原料，也可用于城市煤气及钢铁等其他行业，气化炉烧嘴是该装置中的关键设备之一。 本作者就关于水煤浆气化炉工艺烧嘴的使用及维护方面所进行 的一些工作和思考进行简单的介绍，同时对于该烧嘴的改进方向提供一些个人看法，仅供同行参考。

Shell炉煤气化工艺介绍

Shell炉煤气化工艺介绍 目录 1.概述 1.1.发展历史 1.2. Shell炉煤气化工艺主要特点 2.工艺流程 2.1. Shell炉气化工艺流程简图 2.2.Shell炉气化工艺流程简述 3.气化原理 3.1粉煤的干燥及裂解与挥发物的燃烧气化 3.2.固体颗粒与气化剂(氧气、水蒸气)间的反应3.3.生成的气体与固体颗粒间的反应 3.4.反应生成气体彼此间进行的反应 4.操作条件下对粉煤气化性能的影响 4.1气化压力对粉煤气化性能的影响 4.2氧煤比对粉煤气化性能的影响 4.3蒸汽煤比对粉煤气化性能的影响 4.4.影响加压粉煤气化操作的主要因素 4.5煤组分变化的影响 4.6 除煤以外进料“质量”变化的影响 5.工艺指标 6.Shell炉气化工艺消耗定额及投资估算 7. 环境评价

1.概述 1.1.发展历史 Shell煤气化工艺(Shell Coal Gasfication Process)简称SCGP，是由荷兰Shell国际石油公司(Shell International Oil Products B. V.)开发的一种加压气流床粉煤气化技术。Shell煤气化工艺的发展主要经历了如下几个阶段。 (l)概念阶段20世纪70年代初期的石油危机引发了Shell公司对煤气化的兴趣，1972年Shell公司决定开发煤气化工艺时，对所开发的工艺制定了如下标准: ①对煤种有广泛的适应性，基本可气化世界上任何煤种; ②环保问题少，有利于环境保护; ③高温气化，防止焦油和酚等有机副产品的生成，并促进碳的转化; ④气化装置工艺及设备具有高度的安全性和可靠性; ⑤气化效率高，单炉生产能力大。 根据上述原则，通过固定床、流化床和气流床三种不同连续气化工艺的对比，对今后煤气化工艺的开发形成了如下基本概念: ①采用加压气化，设备结构紧凑，气化强度大; ②选用气流床气化工艺，生产能力大，气化炉结构简单; ③采用纯氧气化，气化温度高，气化效率高，合成气中有效气CO十H2含量高; ④熔渣气化、冷壁式气化炉，熔渣可以保护炉壁，并确保产生的废渣无害， ⑤对原料煤的粒度无特殊要求，干煤粉进料，有利于碳的转化。 (2)小试试验1976年Shell在荷兰阿姆斯特丹建成了规模为6t/d煤的小试装置，该装置的主要任务是进行煤种试验，验证Shell煤气化理论，为工艺模型的开发提供基础数据，并进行材料试验和煤气净化方法试验，收集基本的环保数据。在其主要试验期间(1978-1983年)，先后对21个煤种进行了气化试验。目前该装置仍可根据需要进行特定煤种评价及试验。(3)中试装置在小试试验的基础上，于1978年Shell在原联邦德国的汉堡一哈尔堡(Ham- burg-Harburg)壳牌炼油厂内建设了一套日处理150t煤中试装置。其主要任务是进行不同煤种的气化试验，与小试试验结果关联并验证煤气化数据和工艺模型，进行相关的设备试验，确定煤气化的关键设备(如:气化炉、煤气冷却器、烧嘴、加料及排渣设备及阀门等)的设计原则，为工业化装置的设计提供数据，同时为生产装置积累操作经验、开发安全操作程序。中试装置累计进行了6000h(包括1000h的连续运转)的气化试验，于1983年结束运转。 (4)工业示范装置在汉堡中试的基础上，对气化和煤气冷却系统的设计进行了大幅度的改进，并在美国休斯顿郊区壳牌的Deer Park总厂建设了一套命名为SCGP-1的粉煤气化工业示范装置，该装置于1983年开始设计，1986年开始运转，气化规模为250 - 400t/d煤，气化压力2^-4MPa，约日产32. 5 X 104 m”中热值煤气和16t/h蒸汽。SCGP-1示范装置的主要任务是验证Shell煤气化工艺技术，包括工艺特性及设备可靠性，进一步开发商业化生产的操作技能和经验。SC(aP-1气化装置的示范试验装置累计运行15000h，最长连续运行1500h，气化了大约18种煤(其中包括褐煤和石油焦)，获得了比期望值更好的工艺效果。该示范装置于1991年关闭。 (5)工业化应用1993年采用Shell煤气化工艺的第一套大型工业化生产装置在荷兰布根伦 (Buggenum)市的Demkolec建成，用于整体煤气化燃气一蒸汽联合循环发电，发电量为250MWo设计采用单台气化炉和单台废热锅炉，气化规模为2000t/d煤。煤电转化总(净)

煤气化工艺预案的选择

初探煤气化工艺方案的选择 1 几种煤气化工艺及特点介绍 煤气化是煤化工的龙头技术，是煤洁净利用技术的重要环节，C1化学的基础。煤气化技术是进展煤基化学品、煤基液体燃料、联合循环发电、多联产系统、制氢、燃料电池等过程工业的基础，是这些行业的共性技术、关键技术和龙头技术，对我国经济和保障国家安全具有重要的战略意义。 煤气化过程采纳的气化炉炉型，目前要紧有以下3种： 固定床﹙UGI、鲁奇﹚；

流化床﹙灰熔聚、UGAS、鲁奇CFB、温克勒、KBR、恩德等﹚； 气流床﹙Texaco、Shell、GSP、PRENFLOW、国产新型水煤浆、二段干煤粉、航天炉等﹚。 1.1固定床制气工艺 1.1.1常压固定床间歇制气工艺 工艺特点是：常压气化，固体加料10-50mm，固体排渣，间歇气化，空气和蒸汽作气化剂，吹风和制气时期交替进行，适用原料白煤和焦碳，气化温度800～1000℃。代表炉型有美国的U.G.I型和前苏联的U.G.Ⅱ型。工艺过程都比较熟悉，那个地点从略。 技术优点：历史悠久，技术成熟，设备简单，投资省，生产经验丰富。 技术缺点：技术落后，原料动力消耗高，炭转化率低70～75%，产品成本高，生产强度低，程控阀门多，维修工作量大，废气、废水排放多，污染严峻，面临淘汰。 1.1.2常压固定床连续制气 常压固定床连续制气工艺的技术特点：常压气化，固体加料，床体排渣，连续制气，富氧空气﹙氧占50%﹚或氧气加蒸汽做气化剂，无废气排放，适用煤种白煤和焦碳。

技术优点是：连续制气，炉床温度稳定，约为900～1150℃，操作简单，程控阀门少，维修费用低，生产强度大，碳转化率高，约80～84% 。 技术缺点：需要空分装置，投资比较大。 固定床连续制气工艺的技术突破在于以氧气或富氧空气加蒸汽做气化剂，由于气化剂中氧含量的增加，气化反应过程中，燃烧产生的热量与煤的气化和蒸汽分解所需要的热量能够实现平衡，能够得到稳定的反应温度和固定的反应床层，能够实现连续制气，不用专门吹风，无废气排放，生产强度和能源利用率都有了专门大的提高。 1.1.3 固定床加压气化工艺：前西德鲁奇公司(Lurgi)开发。 工艺特点：加压气化，固体加料，固体排渣，连续气化，氧气和蒸汽作气化剂，设有加压的煤锁斗和灰储斗，适用煤种：褐煤、次烟煤、活性好的弱粘结煤。 技术优点：加压气化3.1 MPa，生产强度大，碳转化率高约90%。 技术缺点：反应温度略低700～1100 ℃，甲烷含量较高，煤气当中含有焦油和酚类物质，气体净化和废水处理复杂，流程较长，投资比较大。