US20090100752A1

US20090100752A1 - Device for converting carbonaceous matter into synthesis gas and associated methods

Info

Publication number: US20090100752A1
Application number: US12/098,632
Authority: US
Inventors: John P. Sessa; Albin Czernichowski; Mieczyslaw Czernichowski; Caroline Czernichowski
Original assignee: Florida Syngas
Current assignee: BLUE FLAME LLC
Priority date: 2004-06-26
Filing date: 2008-04-07
Publication date: 2009-04-23
Also published as: WO2009126229A2; WO2009126229A3; EP2326700A2

Abstract

A device for converting carbonaceous matter into synthesis gas includes a plasma head and a reformer connected to and extending downwardly from the plasma head. The plasma head may include a vortex zone, a plasma zone positioned beneath the vortex zone, and an oxidant input adjacent an upper portion of the vortex zone for inputting oxidant into the vortex zone. The plasma head may also include a high voltage electrode positioned to extend through a medial portion of the vortex zone and having a termination in the vortex zone so that high voltage discharge strikes are emitted into a lower portion of the vortex zone, a carbonaceous matter input for inputting carbonaceous matter into the plasma zone, and a plasma zone exit. The reformer may include a post plasma zone positioned beneath the plasma zone, a thermal barrier protective layer adjacent an uppermost portion of the post plasma zone adjacent an exit of the plasma zone, a catalyst carried by the post plasma zone, and a synthesis gas output.

Description

RELATED APPLICATIONS

The present application is a continuation-in-part of U.S. Patent Application Publication No. 2006/0018823 titled “Plasma-Catalytic Conversion of Carbonaceous Matters” FILED ON Jun. 27, 2005 by Czemichowski et al., which is a continuation-in-part of French patent application serial number 04 07054, filed on Jun. 26, 2004 and a continuation of French patent application Serial No. 04 07054 French patent application serial number 04 07054, filed on Jun. 26, 2004, the entire contents of each of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to the field of converting carbon containing liquid or gas matter to synthesis gas, and devices for accomplishing same.

BACKGROUND OF THE INVENTION

Processes exist for converting carbonaceous matters into synthesis gas. For Example, U.S. Pat. No. 7,089,745 to Roby et al. discloses a system for vaporization of liquid fuels. More specifically, Roby et al. '745 discloses vaporization only in a low oxygen environment to avoid ignition. Vapors are then sent safely to a burner.
U.S. Published Patent Application No. 2004/0134194 also by Roby et al. discloses another system for vaporization of liquid fuels. This system also is directed to vaporization of liquid fuels. U.S. Published Patent Application No. 2006/0154189 to Ramotowski et al. discloses a method for vaporizing liquids, such as fuels. The liquids are vaporized by spraying them onto a hot surface. Accordingly, the entire spray is intercepted by the surface. Heat is added through the surface to maintain an internal surface temperature above the boiling point of the least volatile component of the liquid. The liquid droplets impinge on the surface and, accordingly, are flash vaporized.
U.S. Published Patent Application No. 2007/0254966 to Eskin et al. discloses a process for transforming a coal issued synthesis gas into a liquid fuel. This is performed through a well-known Fischer-Tropsch process. The liquid fuel can then be vaporized and added to another stream of synthesis gas to burn the mixture in a traditional gas turbine.

SUMMARY OF THE INVENTION

In view of the foregoing background, it is therefore an object of the present invention to provide a device and method that efficiently converts carbonaceous matter into synthesis gas.
The present invention concerns a process and a catalytic device to convert various carbonaceous liquids in the presence of oxygen O₂added to these matters. According to this process, matters may be converted mainly into a mixture of hydrogen H₂, carbon monoxide CO, some carbon dioxide CO₂, and steam H₂O. This mixture may be accompanied by minor light hydrocarbons. These gases may be diluted in nitrogen N₂if air is used as an oxygen source. Such a mixture may be referred to as “synthesis gas”, “syngas” or “fuel gas”.
The process includes the conversion of Glycerol (Glycerin), C₃H₈O₃. This feed represents all classes of liquids such as fossil fuels or bio-fuels, vegetable oils, as well as any carbonaceous liquids issued by any industrial process, for instance, from a pyrolysis of wood or any organic matter.
Production of the syngas is already a very important step of natural gas processing, upgrading, and/or valorization, mostly for Hydrogen production or so-called Gas-to-Liquids (GTL) generation of clean liquid synthetic fuels (synfuels). There exists a growing interest for the syngas production from other fossil or renewable liquids to feed classical engines, turbines (including micro-turbines) or various Fuel Cells for combined heat and power (CHP) generation.
A crisis of liquid fuels availability (gasoline, Diesel oil, kerosene) is rapidly approaching. This crisis, however, strengthens not only the classical GTL technologies (use of declining fossil natural gas) but also opens the doors for syngas generation based on bio-oils or even on waste liquids from agro-industry. Resulting syngas can be then converted to really renewable synthesis fuels.
The objects, features and advantages in accordance with the present invention are provided by a device for converting carbonaceous matter into synthesis gas. The device preferably includes a plasma head and a reformer connected to and extending downwardly from the plasma head.
The plasma head preferably comprises a vortex zone and a plasma zone positioned beneath the vortex zone. The plasma head also preferably includes an oxidant input adjacent an upper portion of the vortex zone for inputting oxidant into the vortex zone and a high voltage electrode positioned to extend through a medial portion of the vortex zone and having a termination in the vortex zone so that high voltage discharge strikes are emitted into a lower portion of the vortex zone. The plasma head further comprises a carbonaceous matter input for inputting carbonaceous matter into the plasma zone, and a plasma zone exit.
The reformer may include a post plasma zone positioned beneath the plasma zone of the plasma head, and a thermal barrier protective layer adjacent an uppermost portion of the post plasma zone adjacent an exit of the plasma zone. The reformer may also include a catalyst carried by the post plasma zone, and a synthesis gas output.
The reformer may be housed by a double walled chamber having an entrance adjacent a lower portion thereof and an exit adjacent an upper portion thereof. The oxidant may be inputted into the double walled chamber through the entrance at a first temperature, heated in the double walled chamber, and outputted through the exit at a second temperature.
The carbonaceous matter is preferably glycerol. The oxidant may be inputted into the entrance of the double walled chamber at an ambient temperature. Further, the oxidant may be heated to a temperature between about 250° C. and 350° C. within the double walled chamber. The oxidant may be inputted into the oxidant input on the plasma head at a temperature slightly lower than the output temperature from the double walled chamber of the reformer.
The high voltage discharge strikes are preferably gliding and rotating high voltage discharge strikes. The carbonaceous matter may be reacted with the high voltage discharge strikes to produce a partial reformed product. The plasma head may also include an exit. The partial reformed product may exit the plasma head through the exit, and may be reacted with the catalyst to form synthesis gas.
A plurality of temperature sensors may be included and may be adapted to monitor temperatures throughout the post plasma zone and the reformer. The plasma head may also include a baffle adjacent the oxidant input. The baffle may have a predetermined angle to cause torodial motion of the oxidant in the vortex zone.
The plasma head may also include a metallic nozzle surrounding a medial portion of the electrode. Interior portions of the metallic nozzle may be defined by an hourglass shape. The electrode may be offset from an imaginary concentric line through the hourglass shaped interior portion of the metallic nozzle.
The device may also include a carbonaceous matter metering pump for metering and controlling a flow rate of carbonaceous matter inputted into the carbonaceous matter input. The device may further include an insulator positioned to surround the high voltage electrode adjacent medial portions thereof and terminating so that a lower portion of the electrode is exposed adjacent the metallic nozzle in the vortex zone.
The device may still further include a viscosity meter for metering viscosity of the carbonaceous matter. The viscosity meter may comprise a processor to determine viscosity of the carbonaceous matter. The processor may adjust the viscosity of the carbonaceous matter to a predetermined viscosity prior to input of the carbonaceous matter into the carbonaceous matter input.
The thermal barrier protective layer may be provided by nickel. The temperature adjacent the plasma zone exit may be between about 900° C. and 1250° C. and the high voltage electrode may emit a voltage discharge between about 6 and 25 kV.
A method aspect of the present invention is for converting carbonaceous matter into synthesis gas. The method may comprise preheating an oxidant to a predetermined temperature, inputting the preheated oxidant into a vortex zone, and exposing carbonaceous matter to the preheated oxidant. The method may also comprise reacting the carbonaceous matter that has been exposed to the preheated oxidant to high voltage discharge strikes emitted from an electrode to produce a partial reformed product in a plasma zone, and reacting the partial reformed product with a catalyst to form synthesis gas in a post plasma zone.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph depicting the composition of commercial Diesel fuel.

FIG. 2 is a simplified schematic of the GlidArc I technology.

FIG. 3 is a graph depicting temperature rise over time when using the GlidArc I technology illustrated in FIG. 2.

FIG. 4 is a graph depicting the heating value of a reformulate, and its products according to the fuel flow entering using the GlidArc I technology illustrated in FIG. 2

FIG. 5 is a graph depicting the composition of dry reformate according to the ratio of Oxygen-to-Carbon using the GlidArc I technology illustrated in FIG. 2.

FIG. 6 is a graph depicting component concentration in the outgoing gas, to the proportion of the air/oil, of a device using the GlidArc I technology illustrated in FIG. 2.

FIG. 7 is a graph depicting the exit flux of the syngas as well as the thermal power corresponding to this flux using the GlidArc I technology illustrated in FIG. 2.

FIG. 8 is a graph depicting the flux and the thermal power of exiting syngas using the GlidArc I technology illustrated in FIG. 2.

FIG. 9 is a schematic view of a device for converting carbonaceous matter into synthesis gas according to the present invention.

FIG. 10 is a sectional view of a plasma head of a device for converting carbonaceous matter into synthesis gas according to the present invention.

FIG. 11 is a graph depicting reforming results.

FIG. 12 is a perspective view of a device for converting carbonaceous matter into synthesis gas according to the present invention.

FIG. 13 is a sectional view of a reformer of the device illustrated in FIG. 12 and taken through line 13-13.

FIG. 14 is a partial sectional view of a plasma head of the device illustrated in FIG. 12 taken through line 14-14.

FIG. 15 is a top plan view of a plasma head of a device for converting carbonaceous matter into synthesis gas according to the present invention and having portions cut away.

FIG. 16 is a sectional schematic view showing a device for converting carbonaceous matter into synthesis gas according to the present invention and showing a pump, viscosity meter and carbonaceous matter supply.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This Invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.
FIGS. 1-8 are illustrations that are relative to the first generation of this technology, which is referred to as GlidArc I, and which is the subject of the parent application of this application. More specifically, FIGS. 1-8 are directed to the technology referred to in U.S. Patent Application Publication No. 2006/0018823 titled “Plasma-Catalytic Conversion of Carbonaceous Matters” filed on Jun. 27, 2005 by Czernichowski et al., which is a continuation-in-part of French patent application serial number 04 07054, filed on Jun. 26, 2004 and a continuation of French patent application Serial No. 04 07054 French patent application serial number 04 07054, filed on Jun. 26, 2004, the entire contents of each of which are incorporated herein by reference.
Referring now additionally to FIGS. 9-11, a device for converting carbonaceous matter into synthesis gas, and associated methods are now described in greater detail.
The device for converting carbonaceous matter into synthesis gas is schematically illustrated in FIG. 9. The figure illustrates the invention but those having skill in the art will appreciate that this example is not restrictive for realization of an industrial reactor. The device includes three successive compartments, which are otherwise known as zones.
Zone A of electric discharges and input matter mixing, oxidant 1 and 1 a and carbonaceous feed (liquid or liquid/vapor mix) 2. Zone A is also known as the vortex zone.
Zone B of droplets evaporation and primary high-temperature reforming. Zone B is also known as the evaporation zone.
Zone C of main non-isothermal catalytic reforming and fine-tuning. The upper layer of this zone contains a sensor 3 indicating the highest zone temperature while the temperatures decrease downstream until the syngas product leaves the reformer by an exit 4. Zone C is also known as the post plasma zone.
The oxidant (entering through 1 and initially at ambient temperature) is preheated in a double-wall structure D.
The overall reforming process can be described schematically by the following set of two chemical reactions of Partial Oxidation (POX) of the carbonaceous (organic) feed presenting a formula C_xH_yO_z:
C_xH_yO_z+(x−z)/2O₂ =xCO+y/2H₂ (1)
C_xH_yO_z+(x+y/4−z/2)O₂ =xCO₂ +y/2H₂O (2)
The main weakly exothermic reaction (1) cannot alone heat such a conversion system. In other words, the main exothermic reaction cannot heat the reactor and its contents up to sufficiently high temperatures of at least 900° C. (but not higher than about 1250° C.). These temperatures are necessary for a sufficiently high reaction kinetic in the presence of a low-active catalyst. While the full-combustion reaction (2) gives no desired product, it is highly exothermic. By mixing the two reactions in the right proportion of “p” parts of reaction (2) for (1-p) parts of the reaction (1), a compromise of sufficiently high selectivity of syngas production at sufficiently high temperatures that boost the kinetics of the reaction (1) in the presence of a low-active (so simply and poisoning-resistant) catalyst. The proportion p is kept in the range of 0.1 to 0.3 by setting the Oxygen-to-feed ratio. For example, the Glycerol feed the main reforming (and endothermic) reaction is as follows:
C₃H₈O₃=3CO+4H₂ (1a)
Accordingly, no O₂is needed, and the full combustion reaction is represented as:
C₃H₈O₃+3.5O₂=3CO₂+4H₂O (2a)
Therefore, at the ratio α=0.2 the whole reforming process is:
C₃H₈O₃+0.7O₂=2.4CO₂+3.2H₂+0.6CO₂+0.8H₂O (3)
More specifically, it is evident that (1-p)*100 represents the selectivity (in this case 80%) of Glycerol-into-syngas conversion realized by mixing 0.7 mole of Oxygen and 1 mole of Glycerol. If air (containing roughly 21 vol. % of O₂) is used as Oxygen source the last reaction can be rewritten as:
C₃H₈O₃+3.3 air=2.4CO₂+3.2H₂+0.6CO₂+0.8H₂O+2.6N₂ (3a)
This reaction provides the syngas that is highly diluted by non-reactive Nitrogen from air. Those skilled in the art will appreciate that any oxidizing mixture containing between 21 and 100 vol. % of O₂, for example, an enriched air like “Nitrox36” (an enriched air produced for recreational diving and containing 36 vol. % of O₂) can be used. Nitrox, for example, containing 50-80% of Oxygen is common in technical diving. Commercial Nitrox generators can therefore be used also for a less N₂-diluted syngas production.
A practical realization of the process like (3) or (3a) is performed in the device schematically illustrated in FIG. 9. It is well known that Glycerol (as well as most of waste organic liquids) is inflammable at usual conditions (air as oxidizer, atmospheric pressure, ambient temperature). Such feed can only be “ignited” and then converted at an elevated temperature (roughly starting at 600° C.) so the first task, to be executed, should be to preheat the reformer. This is performed using an easily flammable gas or liquid, such as natural gas (or methane), propane (or LPG), or light gasoline, etc. sent by the entry 2, while an oxidizer, such as air, for example, enters through the inlet 1 a. Of course, those having skill in the art will appreciate that this mixture must be ignited. Almost any kind of electric discharge can be applied in Zone A. It is preferable, however, that a rotating electric discharge is used, such as, for example, GlidArc-III™ (see French Patent No. 2 873 306, the contents of which are incorporated herein by reference) perfectly adapted for this task. This plasma igniter is illustrated in FIG. 10.
Zones B and C are thermally insulated from the outside by Jacket D to maximally limit the heat loses. As will be discussed in greater detail below, jacket D is provided by a double walled chamber. The jacket D acts as an entering oxidant preheater as well. Accordingly, the factor α is reduced and, therefore, the amount of syngas produced is increased from a unit of processed carbonaceous liquid. It is preferable that no part of the reactor is cooled.
Between about 80 and 90% of the oxidant 1 a is directed to a vortex-like zone 4 that protects a central electrode 5 and its insulating support 5 a while the remaining part of the oxidant can be sent through the input 2, together with the heating fuel to the plasma zone 6 where the gliding and rotating high-voltage alternating current (AC) discharge strikes between the central electrode and the surrounding metallic nozzle 7 being at the ground potential.
Once the sensor 3 indicates a sufficiently high temperature, which is preferable between about 900 and 1250° C., the fuel flow rate is progressively reduced and at the same time the liquid feed flow rate is advantageously increased. During this operation, the temperature is preferably kept within the above-mentioned range. It is preferable to keep these temperatures in the range by controlling the ratio R of oxidant to (fuel+feed). The ratio R is increased when the temperature decreases, and vice-versa. At the end of the reformer start-up operation, the preheating fuel flow rate is stopped so that the reformer is ready for use. The oxidant flow rate may then be progressively increased, as well as the liquid feed flow rate to keep the reforming operation in the preferred temperature range between about 900° C. and 1250° C. When increasing the oxidant and the feed flow rate (loading of the reformer), a given temperature (still in the above mentioned range) can be obtained at a lower ratio R, corresponding to a lower factor α and, therefore, to better feed reforming selectivity into syngas.
The syngas composition (and therefore its quality and/or applicability for a given use) for a given reformer size/volume depends on several variables. These variables may, for example, include

- a) Feed composition,
- b) Oxidizer composition,
- c) Ratio R (or otherwise, the parameter p),
- d) Reformer loading (ratio of the feed flow rate with respect to the volume of the zones B and C), and,
- e) Catalytic matter present in the zones B and C.

It is therefore crucial to analyze on-line the syngas composition as a function of mainly the above referenced variables c) and d) for given constants a), b), and e). Once the syngas composition is established, the reforming parameters may be set, and may be used as a scenario for a simple and efficient process to control in full range the desired feed flow rates (and therefore, the syngas output power).
The chemical analyses of cold exiting gas (syngas) are performed by using the gas chromatography (GC).Two-channel micro-GC is used and is dedicated to H₂, O₂, N₂, CH₄and CO for the first channel and to CO₂, C₂H₄, C₂H₆, C₂H₂, C₃H₆+C₃H₈and H₂O (as residual gas moisture) for the second channel. The total amount of H₂O in hot syngas is calculated from mass balances based on inert N₂as internal standard. A complete gas analysis takes place in approximately 255 seconds.
As shown on FIG. 9 the two compartments B and C are positioned in series in relation to the flux of reagents and products. The first phase of the POX conversion of carbonaceous feed is already started in the plasma zone. In the plasma zone, a rather full oxidation process (2) is observed as a part of the feed in its gaseous/vapor phase, while, most of feed droplets crosses the zone untreated. Such very hot and heterogeneous mixture then collides and crosses a short zone B filled by Nickel balls (5-12 mm diameter, 2-8 cm height). The contact time of the heterogeneous flow with the zone B balls is very short, in milliseconds. Two main processes take place:

- 1. Complete droplets disappearance/evaporation in contact with the hot balls (the balls heat due to an intensive contact with the flame and transfer this heat into the droplets) and,
- 2. Over-oxidation mostly following the process (2).

Before arriving to Zone B, some droplets may immerge in the very hot plasma-enhanced flame, but may, however, partially pyrolyse into nasty molecular fragments, or even soot or coke. These undesired products are processed in the Zone C.
The main process occurs In the Zone C filled by a catalyst. Nickel metal and Nickel Oxides are present on the surface and inside of porous refractory matter (similar to fired clay or alumina). As described above, the stream of partially reacted gas may still contain some non-reacted vapors of initial feed, an excess of CO₂and steam at a high temperature (between about 900° C. and 1250° C.). In the presence of the catalyst, the back endothermic processes of so-called “dry reforming” and “steam reforming” take place as follows:
C_xH_yO_z+CO₂→CO+H₂ (4)
C_xH_yO_z+H₂O →CO+H₂ (5)
Progressively, non-reacted feed disappears, pumping the heat from its hot environment—the hot stream leaving the Zone B. Consequently, the temperatures decrease downstream and completely reacted gas leaves the last catalyst's layer of the Zone C, and thereafter, the output pipe 4 at moderate temperatures ranging between about 400° C. and 600° C. The overall process system can be described by the reactions (1) and (2) despite the initial over-oxidation of a part of the feed followed by dry- and steam-reforming (4) and (5), respectively. One more process takes place in the zone C—so-called “water shift” and is signified as follows.
CO+H₂O═CO₂+H₂ (6)
This reaction provides an excess of Hydrogen and a deficit of Carbon Monoxide with respect to the calculated concentrations based on reactions (1), (2) and parameter p. It does not, however, change greatly when syngas is devoted for CHP generation, as the Lower Heating Value (LHV) of the syngas remains almost constant. For some specific applications, such an extra amount of H₂can be interesting (like for waste-liquids into Hydrogen route). It happens that the reaction (6) is enhanced by the same catalyst mainly devoted to the dry- and steam-reforming.
The catalyst precursor loaded in Zone C becomes active since its first utilization. During the process start-up, the entire reformer is heated (so that zone C as well) at mostly oxidizing condition (for example, an excess of air). In these conditions, all Nickel (whatever is its initial chemical formula) becomes completely oxidized. Main Nickel oxides, such as, for example, NiO, Ni₃O₄, and Ni₂O₃change toward the other according to the temperature and available amount of the Oxygen. This property Is used for our catalytic POX process of carbonaceous matter.
The process of total conversion (100%) of carbonaceous feed (no trace of this feed found in the syngas) is explained by the following reasons: metallic Ni and its oxides NiO_x(global formula) initially present on (and inside) the porous granules in Zone C react with certain products of the oxidant (“oxidation”) and pyrolysis done in the Zones A and B. The two cases can be distinguished as follows:
These oxides or metallic Nickel increase their state of oxidization, for example:
Ni+H₂O═NiO+H₂ (7a)
Ni+CO₂═NiO+CO (7b)
2NiO+H₂O═Ni₂O₃+H₂ (7c)
2NiO+CO₂═Ni₂O₃+CO (7d)
either reaction decrease it, for example
2Ni₂O₃═C₂H₄=4NiO+2CO+2H₂ (8a)
2NiO+C₂H₂=2Ni+2CO+H₂ (8b)
NiO+C═Ni+CO (8c)
NiO+heavy tars→Ni+CO+H₂ (8d)
Nickel and its oxides therefore became very active donors and receptors of Oxygen. These cyclic oxidation/reduction processes drive the whole feed conversion into desired syngas.
It may, however, happen that due to some errors during start-up operation a massive and undesirable pyrolysis of feed occurs in Zones B and/or C. In such a process, soot and/or coke and/or very heavy tars are generated. These products are partially blown out from the reformer and pollute the syngas. Moreover, soot and coke, according to our study, catalyzes the pyrolysis itself so that a backpressure appears on the reformer and, finally, the whole Zone C can be plugged after certain time. When such an unwanted process starts occurring and when the sensor 3 still indicates a temperature of at least 700° C., it is counteracted by stopping the feed input and drastically reducing the oxidant flow rate. In such conditions, an intensive combustion of metallic Nickel, its lower oxides, and all pyrolytic products can be observed.
The temperature can increase up to 1250° C., but should not be allowed to increase. This is prevented by controlling the oxidant flow rate. Once the Nickel balls and the first layer of the catalyst are cleaned, the process moves itself downstream due to progressive heat transfer so that temperatures become high enough to progressively ignite deeper layers of polluted catalyst. By such moving layer-per-layer full combustion whole Zone B and C may become ready again to reform the feed. It is preferable to keep the temperature of moving combustion layers below 1250° C. to avoid the destruction of the catalyst.
In cases when the sensor 3 indicates a temperature below 700° C., the moving cleanup process cannot start, but can still be counteracted by proceeding a cold start-up-like operation sending a bit of the fuel and oxidant in the presence of electric discharge in order to heat Zone B and the first layer of the zone C. When the sensor/3/indicates at least 700° C., we can stop the fuel and proceed the layer-per-layer cleaning as described in previous subsection.
The reforming process can be active during one day (or more). If slowly progressing catalyst deactivation appears (due to soot/coke deposits on it), making the reforming less efficient—one can execute the described-above catalyst reactivation taking roughly ½ hour.

Experimental Results of Glycerol Reforming

1st Trial

Instead of waste crude Glycerol from a Bio-Diesel plant, we took a quite clean Glycerol. The Glycerol had a specific gravity at 21° C. of 1236 kg/m³that indicates its water content of 9 wt. %. The Lower Heating Value of this sample is 4.1 kWh/kg so only 35% of Diesel Oil LHV value.
A precise piston-dosing pump is used for the feed injection. Our smallest GlidArc-assisted reformer was used for the tests. It has only 0.18-L plasma space and a 0.57-L post plasma zones B and C. The reformer is devoted to work under high pressure (up to 22 bars) but the trial is performed at close-to-atmospheric pressure. A small flow [0.8 to 2.2 L(n)/min] of the pipe-grade Natural Gas (NG) is added to the Glycerol stream and the mixture is sent to a T-connector. Air/O2 mixture enters the reformer's double-wall chamber where it is preheated. The NG/Glycerol bi-phase flow is injected into Zone A. Partially reformed reactants then cross Zones B and C where three thermocouples are installed for the temperature sensing (up to about 1250° C.). Hot syngas (SG) exits the reformer, cools in a rudimentary cooler, and is then flared. A small SG sample is analyzed online using a μ-GC.
Twelve runs are performed at various operating conditions:


Constant GlidArc power	0.05	kW
Glycerol input flow rate	1-16	g/min
Auxiliary NG input flow rate	1.5-2.2	L (n)/min
NG Lower Heating Value (LHV) input power	0.5-1.4	kW
Air input flow rate	4.6-14	L (n)/min
Oxygen input flow rate	0-4.8	L (n)/min
O₂content in oxidizer	21-61	vol. %

Based on a precise mass balance (N₂+Ar conservation as inert gases) we have obtained the following results at the reformer exit:


SG output flow rate (dry)	17-30	L (n)/min
SG LHV output power	1.1-2.9	kW
LHV released from glycerol	1.2-2.6	kWh/kg
LHV of the SG (dry)	1.0-2.0	kWh/m³(n)

Some input/output data are presented in two tables that follow:


	Gly IN	NG IN	air IN	O2 IN	SG OUT	SG composition (dry, vol. %)

run	g/min	L(n)/min	CO2	C2H4	H2	N2 + Ar	CH4	CO

gly01	6.14	0.81	2.90	0.00	17.7	11.5	0.18	16.2	61.7	2.3	8.0
gly02	6.14	0.81	2.90	0.00	18.4	13.8	0.25	16.2	59.4	2.7	7.6
gly03	7.87	2.2	5.64	2.75	25.3	18.9	0.04	23.9	43.3	1.2	12.7
gly04	7.87	2.2	5.64	2.75	25.7	18.2	0.02	25.0	42.7	0.9	13.3
gly05	9.35	2.2	5.64	2.75	27.5	17.5	0.04	27.7	39.9	1.1	13.9
gly06	11.8	1.5	5.64	2.75	28.1	18.4	0.02	26.5	39.0	1.1	15.1
gly07	13.0	1.5	4.60	1.71	29.7	16.3	0.16	29.3	36.8	2.0	15.4
gly08	14.9	0.81	4.60	1.71	28.5	16.3	0.28	28.5	38.3	2.3	14.2
gly09	14.6	0.81	4.78	2.75	24.4	21.5	0.40	30.2	31.5	3.0	13.4
gly10	14.7	0.81	5.27	3.79	21.5	24.8	0.41	31.5	26.1	2.8	14.2
gly11	15.7	0.81	5.79	4.83	19.5	28.2	0.38	34.0	18.7	2.9	15.8
gly12	15.7	0.81	5.27	4.31	20.8	27.8	0.38	34.3	17.5	2.9	17.0


	LHV power kW	kWh/kg	kWh/m³	Thermal eff.

run	NG IN	SG OUT		of Gly	SG OUT	%

gly01	0.50	1.1	0.61	1.6	1.0	41
gly02	0.50	1.2	0.69	1.9	1.1	46
gly03	1.4	2.0	0.58	1.2	1.3	30
gly04	1.4	2.0	0.64	1.4	1.3	34
gly05	1.4	2.4	0.99	1.8	1.4	43
gly06	0.93	2.4	1.5	2.1	1.4	52
gly07	0.93	2.9	2.0	2.6	1.7	64
gly08	0.50	2.8	2.3	2.6	1.6	64
gly09	0.50	2.6	2.1	2.4	1.8	58
gly10	0.50	2.3	1.9	2.1	1.8	52
gly11	0.50	2.3	1.8	1.9	1.9	47
gly12	0.50	2.5	2.0	2.1	2.0	52

The following observations, conclusions and claims can be noted:

- Using the Partial Oxidation, we can reform Glycerol into a gas (SG) with an O₂-enriched air. Even using our smallest GlidArc reformer (that presents considerable heat loses) we obtain 2.6 kWh of LHV from 1 kg of this feed (input NG not accounted). Much higher performances are expected using larger reformers and the process optimization.
- Run “Gly08” seems to be optimal when using only slightly enriched air (containing only 30 vol. % of O₂).
- LHV of such gas (SG) can reach a 2.0 kWh/m³(n). This presents only a 20% of the Methane LHV but this value is much higher comparing to the fuel gases from the wood gasification. Our gas can therefore be considered as a good fuel gas for reciprocating engines or gas turbines.
- This gas contains up to 51 vol. % of H₂+CO at an approximate H2/CO molar ratio of 2. Such syngas can therefore also be considered as a feed for syntheses of clean liquid fuels (mostly the Diesel Oil).
- After the reformer cooling and dismantling, we did not find any harm nor soot/coke deposits inside Zone A as well as Zones B and C.

2nd Trial

Using the same feed, we ran for 4 hours at 14.7 g/min feed rate without any problem.

3rd Trial

After the 2nd trial we immediately started sending a real waste Glycerol from a Bio-Diesel plant. At the same feed flow rate the produced syngas was pulsating and containing soot. We were continuing the test anyway, but after 4 h 15 min the reformer became totally plugged so that the run had to be stopped. After the reformer cooled we opened it and found its Zones B and C almost completely filled with a salt.
We concluded that our reformer/process could not accept a waste Glycerol containing mineral salts or soaps. Such substances must be first removed. A proposed removal method is a simple (so not fractionated) distillation at around 290° C. In such a way, one would recover all Glycerol as well as most of volatile organics (like methanol). For that operation a heat will be available from our reforming process itself as well from the engine exhaust. Water content in such-a-way-produced Glycerol will not be a problem.

4th Trial

It was done using a low-grade (97%) Glycerol presenting the LHV of 4.3 kWh/kg. The same small reformer was used. The feed rate was kept constant at 9.79±0.01 g/min for almost the entire 12-hour run except the last 30 minutes when we have increased it to 12.9 g/min.
Fourteen syngas analyses were performed at almost the same operating conditions of the trial. During the first 6-hour period, we kept all the operating conditions constant and then we started to slightly change them in the second half of the run:


Constant GlidArc power	0.05	kW
Glycerol input flow rate	9.79 or 12.9	g/min
Auxiliary NG input flow rate	0.5	L (n)/min
NG Lower Heating Value (LHV) NG power	0.3	kW
Air input flow rate	9.7 to 14	L (n)/min
Oxygen input flow rate	0 to 1.4	L (n)/min
O₂content in oxidizer	21 to 28	vol. %

Based on a precise mass balance (N₂+Ar conservation as inert gases) we have obtained the following results from the reformer exit:


SG output flow rate (dry)	18-28	L (n)/min
SG LHV output power	1.2-2.5	kW
LHV released from glycerol	1.2-2.6	kWh/kg
LHV of the SG (dry)	0.9-2.2	kWh/m³(n)

The following observations, conclusions and claims can be noted from the above referenced trial:

- The process can be run for at least 12 hours without any problem (7.15 kg of Glycerol totally converted). After the reformer cooled and was dismantled, we did not find any harm nor soot/coke/salts deposits inside Zones A, B or C.
- Using the POX, Glycerol can be reformed into a gas (SG) with a slightly O₂-enriched air (less than 30 vol. % O₂). Even using our smallest reformer we obtain 2.9 kWh of LHV from 1 kg of this feed (input NG not accounted). Much higher performances are expected using larger reformers and the process optimization.

LHV of such gas (SG) reaches 1.5 kWh/m³(n); this time we worked at much lower O₂concentration in the enriched air—so at much higher N₂ballast. Such gas can still be considered as a good fuel gas for reciprocating engines or gas turbines.

- This gas has a H₂/CO molar ratio of 2.2, this means that is may also be considered as an ideal feed for the syntheses of clean liquid fuels using a Cobalt-based catalyst.

5th Trial

All tests are performed in our 1.4-L reformer, which is twice as big with respect to the previous reformer. The same 97% Glycerol is used. Our previously used piston-dosing pump could no longer be used for much larger feed flow rates. Low frequency pulsation caused instabilities of the reforming so that a gear-type pump that was used for the liquid feeding. Desired flow rates were established using serial and parallel manual valves. We checked the liquid flow-rates several time during the tests by weighting the sample pot (from which the feed is sucked by the pump) for a given time range. A serial rotameter showed stability of the flow at a relative scale.
Thirteen syngas analyses were performed at various operating conditions. The operating conditions were the following:


Constant GlidArc power	0.05	kW
Glycerol input flow rate	13-52	g/min
Auxiliary NG input flow rate	0.5	L (n)/min
NG Lower Heating Value (LHV) NG power	0.3	kW
Air input flow rate	25-54	L (n)/min

This time air was used and, accordingly, no auxiliary Oxygen was used. Such operation was made possible but there was a need to vaporize the feed (before its injection through the input 2) using an electric oven set to 300° C. Electric power that was dissipated in the oven was roughly at 1 kW.
Based on a precise mass balance (N₂+Ar conservation as inert gases) we have obtained the following results from the reformer exit


SG output flow rate (dry)	26-127	L (n)/min
SG LHV output power	1.9-14	kW
LHV released from the feed	2.4-4.5	kWh/kg
LHV of the SG (dry)	1.1-2.0	kWh/m³(n)

FIG. 3 presents the reforming results. It appears that almost 90% of initial energy content can be extracted from Glycerol at the LHV of obtained fuel gas of 2 kWh/m³(n) (so about ⅕ of methane LHV). Such value should be sufficient to run an engine or turbine.
Using the Partial Oxidation Glycerol can be reformed into a gas (SG) without any extra Oxygen. Such optimal reforming would ask 1.1 L(n) of air per gram of Glycerol giving the fuel gas having its LHV around 1.8 kWh/m³(n).
Referring now additionally to FIGS. 12 through 16, additional features of the device 40 for converting carbonaceous matter into synthesis gas is now described in greater detail. The device 40 includes a plasma head 42 and a reformer 44 connected to and extending downwardly from the plasma head.
The plasma head 42 may include a vortex zone 46, and a plasma zone 48 positioned beneath the vortex zone. The plasma head 42 may also include an oxidant input 50 adjacent an upper portion of the vortex zone 46 for inputting oxidant into the vortex zone. The oxidant that is inputted via the oxidant input 50 into the vortex zone 46 has been described in greater detail above.
The plasma head 42 also includes a high voltage electrode 52 positioned to extend through a medial portion of the vortex zone 46. The high voltage electrode 52 preferably has a termination in the vortex zone 46 so that high voltage discharged strikes are emitted into a lower portion of the vortex zone, The high voltage electrode 52 is illustratively an elongate electrode.
The plasma head 42 may also illustratively include a carbonaceous matter input 54 for inputting carbonaceous matter into the plasma zone 48. The carbonaceous matter input 54 is illustrated as being towards a lower portion of the plasma zone 48, but those skilled in the art will appreciate that the carbonaceous matter input is preferably adjacent the termination point of the high voltage electrode 52. More specifically, it is advantageous for the carbonaceous matter to be inputted into the plasma head 42 where the high voltage discharge strikes are emitted from the high voltage electrode 52 to cause the reactions discussed in greater detail above.
The plasma head 42 includes a plasma zone exit 56. As will be described in greater detail below, a reaction between the oxidant and the carbonaceous matter adjacent the termination point of the high voltage electrode 52 produces a partial reformed product. This partial reformed product is discharged from the plasma zone 48 via the plasma zone exit 56.
The reformer 44 includes a post plasma zone 58 positioned beneath the plasma zone 48 of the plasma head 42. A thermal barrier protective layer 60 is positioned adjacent an upper most portion of the post plasma zone 58 adjacent the plasma zone exit 56. A catalyst 62 is carried by the post plasma zone 58. As will be discussed in greater detail below, the partial reformed product reacts with the catalyst to produce the synthesis gas. This reaction was also described in greater detail above. The synthesis gas is discharged through the synthesis gas output 64.
As perhaps best illustrated in FIGS. 13 through 17, the reformer 44 is housed by a double-walled chamber 68 having an entrance 70 adjacent a lower portion thereof and an exit 72 adjacent an upper portion thereof. The oxidant is preferably inputted into the double-walled chamber 68 through the entrance 70 at a first temperature. The oxidant is then heated in the double-walled chamber 68, and outputted through the exit 72 at a second temperature. More particularly, the oxidant may be inputted into the entrance 70 of the double-walled chamber 68 at ambient temperature. Further, the oxidant may be heated to a temperature between about 250° C. and 350° C. within the double-walled chamber 68. Accordingly, the oxidant may be inputted into the oxidant input 50 in the plasma head 42 at a temperature slightly below the temperature that the oxidant exited the double-walled chamber 68 of the reformer 44. In other words, there is some inherent temperature loss of the oxidant when the oxidant exits the reformer 44 and enters the plasma head 42. This temperature loss, however, is minor, and likely to be negligible.
As described in greater detail above, the carbonaceous matter is preferably provided by glycerol. Further, the high voltage discharge strikes from the electrode 52 are preferably gliding and rotating high voltage strikes. The carbonaceous matter may be reacted with the high voltage discharge strikes to produce a partial reformed product that exits the plasma head exit 74 through the plasma zone exit 56. As described in great detail above, this partial reformed product is reacted with the catalyst to form synthesis gas.
As illustrated in FIG. 13, the device 40 also may include a plurality of temperature sensors 76 that are adapted to monitor temperatures throughout the post plasma zone 58 and throughout the reformer 44. Those skilled in the art will appreciate that the temperature sensors can be provided anywhere within the post plasma zone 58 and the reformer 44 and that any number of temperature sensors may be used to accomplish the goals and features of the present invention.
As perhaps best illustrated in FIG. 15, the plasma head 42 may comprise a baffle 66 adjacent the oxidant input 50. The baffle 66 preferably has a predetermined angle. It is this predetermined angle of the baffle that causes torodial motion of the oxidant in the vortex zone 46. This torodial motion advantageously enhances the reaction between the oxidant and the carbonaceous matter.
The plasma head 42 also illustratively includes a metallic nozzle 78 that surrounds medial portions of the high voltage electrode 52. More specifically, and as described above, the high voltage electrode 52 has an elongate body. The electrode 52 extends through the medial portion of the metallic nozzle 78. Interior portions of the metallic nozzle 78 are preferably defined by an hourglass shape. In other words, an upper portion of the metallic nozzle is defined by a first predetermined radius, while the medial portion of the metallic nozzle is defined by a second predetermined radius that is substantially smaller than the first predetermined radius. A lower portion of the metallic nozzle 78 is defined by a third predetermined radius which may be substantially similar to the first predetermined radius, but that is substantially larger than the second predetermined radius. The high voltage electrode 52 is preferably offset from an imaginary concentric line through the hourglass shaped interior portion of the metallic nozzle 78.
As schematically illustrated in FIG. 16, the device 40 also includes a carbonaceous matter metering pump 80 for metering and controlling a flow rate of the carbonaceous matter that is inputted into the carbonaceous matter input 54. A viscosity meter 82 may also be included for metering viscosity of the carbonaceous matter. The viscosity meter is preferably positioned adjacent the carbonaceous matter metering pump 80.
The viscosity meter 82 may include a processor for determining viscosity of the carbonaceous matter. The processor may also be used to adjust the viscosity of the carbonaceous matter to a predetermined viscosity prior to input of the carbonaceous matter into the carbonaceous matter input 54. Viscosity of the carbonaceous matter may easily be adjusted by adding water, or evaporating water out of the carbonaceous matter, for example.
The viscosity meter 82 and the metering pump 80 are preferably placed in line with a carbonaceous matter supply 85. The carbonaceous matter supply 85 may, for example, be provided by a 55 gallon drum of carbonaceous matter that is set up to feed directly into the carbonaceous matter input 54.
An insulator 84 may be positioned to surround the high voltage electrode 52 adjacent a medial portion thereof. More specifically, the insulator 84 preferably has a termination point so that a lower portion of the electrode 52 is exposed adjacent the metallic nozzle 78 in the vortex zone 46. As described above, and as perhaps best illustrated in FIG. 14, the metallic nozzle 78 preferably has an hourglass shape, and the electrode 52 is preferably positioned to be offset from an imaginary concentric line through a medial portion of the hour-glass shaped interior. The electrode 52 is preferably offset within the metallic nozzle 78 so that the high voltage discharge strikes may be initially arched off of portions of the metallic nozzle 78. The initial arching of the high voltage discharge strikes is possible by positioning the electrode 52 closer to one particular side of an interior portion of the metallic nozzle 78, i.e., offsetting the electrode.
As described in great detail above, the thermal barrier protective layer 60 may be provided by nickel material. The nickel material that provides the thermal barrier protective layer 60 may, for example, be a plurality of nickel balls, or a nickel screen. Those skilled in the art will appreciate that the thermal barrier protective barrier 60 may be provided by a cylinder type of structure.
The temperature adjacent the plasma zone exit 56 is preferably between 900° C. and 1250° C. This is also discussed in greater detail above. The high voltage electrode 52 preferably emits a voltage discharge between about 6 and 25 kV.
As discussed at length above, the device 40 for converting carbonaceous matter into synthesis gas may emit excess heat. The device 40 is preferably insulated to reduce heat loss. Those skilled in the art will appreciate that the heat emitted from the device 40 may be harnessed for several purposes. For example, the heat may be harnessed in a heat exchange system. This heat exchange system may, in turn, be used in any number of known applications. For example, the heat exchange system may be used to heat hot water or even provide heating of ambient air within a structure.
As described in greater detail above, it is preferable that the glycerol is purified using heat. Those skilled in the art will therefore appreciate that the heat from the system may be harnessed and used upstream to purify the glycerol before being inputted into the plasma head.
The appended illustrations configure device 40 in a vertical manner. Those skilled in the art will appreciate, however, that the device 40 may be configured in any manner, including horizontal. Accordingly, any reference to upward and downward, or upper and lower, are also construed by those skilled in the art as upstream and downstream.
A method for converting carbonaceous matter into synthesis gas is now described in greater detail. The method may include preheating an oxidant to a predetermined temperature and inputting the preheated oxidant into the vortex zone 46. The method may also include exposing carbonaceous matter to the preheated oxidant, in reacting the carbonaceous matter that has been exposed to the preheated oxidant to high voltage discharge strikes emitted from the electrode 52. This reaction produces a partial reformed product in the plasma zone 48. The method may also include reacting the partial reformed product with a catalyst to form synthesis gas in the post plasma zone 58.
Many modifications and other embodiments of the Invention will come to the mind of one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is understood that the invention is not to be limited to the specific embodiments disclosed, and that modifications and embodiments are intended to be included within the scope of the appended claims.

Claims

1. A device for converting carbonaceous matter into synthesis gas, the device comprising:

a plasma head; and

a reformer connected to and extending downwardly from said plasma head;

wherein said plasma head comprises

a vortex zone,

a plasma zone positioned beneath the vortex zone,

an oxidant input adjacent an upper portion of the vortex zone for inputting oxidant into the vortex zone,

a high voltage electrode positioned to extend through a medial portion of the vortex zone and having a termination in the vortex zone so that high voltage discharge strikes are emitted into a lower portion of the vortex zone,

a carbonaceous matter input for inputting carbonaceous matter into the plasma zone, and

a plasma zone exit, and

wherein said reformer comprises

a post plasma zone positioned beneath the plasma zone of said plasma head,

a thermal barrier protective layer adjacent an uppermost portion of the post plasma zone adjacent an exit of the plasma zone,

a catalyst carried by the post plasma zone, and

a synthesis gas output.

2. A device according to claim 1 further wherein the reformer is housed by a double walled chamber having an entrance adjacent a lower portion thereof and an exit adjacent an upper portion thereof; and wherein the oxidant is inputted into the double walled chamber through the entrance at a first temperature, heated in the double walled chamber, and outputted through the exit at a second temperature.

3. A device according to claim 1 wherein the carbonaceous matter is glycerol.

4. A device according to claim 2 wherein the oxidant is inputted into the entrance of the double walled chamber at ambient temperature; wherein the oxidant is heated to a temperature between about 250° C. and 350° C. within the double walled chamber; and wherein the oxidant is inputted into the oxidant input on the plasma head at a temperature slightly lower than the output temperature from the double walled chamber of the reformer.

5. A device according to claim 1 wherein the high voltage discharge strikes are gliding and rotating high voltage discharge strikes.

6. A device according to claim 1 wherein the carbonaceous matter is reacted with the high voltage discharge strikes to produce a partial reformed product.

7. A device according to claim 6 wherein the plasma head further comprises an exit; wherein the partial reformed product exits the plasma head through the exit; and wherein the partial reformed product is reacted with the catalyst to form synthesis gas.

8. A device according to claim 1 further comprising a plurality of temperature sensors adapted to monitor temperatures throughout the post plasma zone and the reformer.

9. A device according to claim 1 wherein the plasma head further comprises a baffle adjacent the oxidant input; and wherein said baffle has a predetermined angle to cause torodial motion of the oxidant in the vortex zone.

10. A device according to claim 1 wherein said plasma head further comprises a metallic nozzle surrounding a medial portion of the electrode.

11. A device according to claim 10 wherein interior portions of the metallic nozzle are defined by an hourglass shape; and wherein the electrode is offset from an imaginary concentric line through the hourglass shaped interior portion of the metallic nozzle.

12. A device according to claim 1 further comprising a carbonaceous matter metering pump for metering and controlling a flow rate of carbonaceous matter inputted into the carbonaceous matter input.

13. A device according to claim 10 further comprising an insulator positioned to surround the high voltage electrode adjacent medial portions thereof and terminating so that a lower portion of the electrode is exposed adjacent the metallic nozzle in the vortex zone.

14. A device according to claim 1 further comprising a viscosity meter for metering viscosity of the carbonaceous matter; and wherein the viscosity meter comprises a processor to determine viscosity of the carbonaceous matter and adjust the viscosity of the carbonaceous matter to a predetermined viscosity prior to input of the carbonaceous matter into the carbonaceous matter input.

15. A device according to claim 1 wherein the thermal barrier protective layer is provided by nickel.

16. A device according to claim 1 wherein the temperature adjacent the plasma zone exit is between about 900° C. and 1250° C.

17. A device according to claim 1 wherein the high voltage electrode emits a voltage discharge between about 6 and 25 kV.

18. A method for converting carbonaceous matter into synthesis gas, the method comprising the steps of:

preheating an oxidant to a predetermined temperature;

inputting the preheated oxidant into a vortex zone;

exposing carbonaceous matter to the preheated oxidant;

reacting the carbonaceous matter that has been exposed to the preheated oxidant to high voltage discharge strikes emitted from an electrode to produce a partial reformed product in a plasma zone; and

reacting the partial reformed product with a catalyst to form synthesis gas in a post plasma zone.

19. A method according to claim 18 wherein the carbonaceous matter is glycerol.

20. A method according to claim 18 wherein the oxidant is preheated to a temperature between about 250° C. and 350° C. and wherein the oxidant is inputted into the vortex zone at a temperature slightly lower than the preheated temperature.

21. A method according to claim 18 wherein the high voltage discharge strikes are gliding and rotating high voltage discharge strikes.

22. A method according to claim 18 further comprising monitoring a temperature within the post plasma zone.

23. A method according to claim 18 wherein the oxidant is introduced into the vortex zone by passing it over a baffle to cause torodial motion of the oxidant in the vortex zone.

24. A method according to claim 18 further comprising metering and controlling a flow rate of the carbonaceous matter being exposed to the preheated oxidant.

25. A method according to claim 18 further comprising metering viscosity of the carbonaceous matter, and adjust the viscosity of the carbonaceous matter to a predetermined viscosity prior to exposing the carbonaceous matter to the preheated oxidant.

26. A method according to claim 19 wherein the temperature adjacent the plasma zone exit is between about 900° C. and 1250° C.

27. A method according to claim 19 wherein the high voltage electrode emits a voltage between about 6 and 25 kV.