CN103402911A - Systems and methods for maintaining sulfur concentration in a syngas to reduce metal dusting in downstream components - Google Patents

Abstract

This invention provides a system and method for maintaining a sulfur concentration in syngas. The method may include combining sulfur with a carbonaceous material to generate a sulfur-containing carbonaceous feed. The method further includes gasifying at least a portion of the sulfur-containing carbonaceous feed to generate syngas and detecting the sulfur concentration in the syngas. The method also includes adjusting the amount of sulfur combined with the carbonaceous material based on the detected sulfur concentration.

Description

Systems and methods for maintaining sulfur concentration in syngas to reduce metal dusting in downstream components

Cross References to Related Applications

This application claims priority to US Patent Application Serial No. 12/982,523, filed December 30, 2010, which is hereby incorporated by reference.

background

The described embodiments generally relate to systems and methods for producing synthesis gas. More specifically, such embodiments relate to systems and methods for maintaining sulfur concentrations in syngas to reduce metal dusting in downstream components.

Related technical description

The gasifier produces synthesis gas or "syngas" and this synthesis gas can be further processed downstream. Due to the interaction with the synthesis gas, especially at high temperatures, downstream components consisting of metal, such as heat exchange tubes, can suffer from metal dusting, also known as carburization. The term "metal dusting" refers to severe and aggressive corrosion that can fragment metal into dust or powder.

Various approaches have been used to reduce the causes and/or effects of metal dusting. One approach is to select alloys that are resistant to metal dusting for downstream components. Another approach is to apply coatings to downstream components using coating materials that minimize metal dusting. However, both of these approaches require costly changes and/or replacement of components used in existing gasifier systems.

Sulfur is a known inhibitor of metal dusting. Sulfur can be absorbed onto the surface of the metal and prevent the transfer of carbon from the gas to the metal. Typical feeds to gasifiers, such as or carbonaceous feedstocks, contain sulfur. However, the sulfur levels in the feed to these gasifiers may be below the minimum level of sulfur required to reduce or prevent metal dusting.

Accordingly, there is a need for systems and methods for producing syngas with sufficient sulfur concentrations to reduce metal dusting in components downstream of the gasifier.

Brief description of the drawings

FIG. 1 depicts a schematic diagram of an illustrative gasification system for producing syngas at a concentration sufficient to reduce gasification in downstream components of one or more gasifiers, according to one or more embodiments described. metal dusting.

Figure 2 depicts a schematic diagram of another illustrative gasification system for producing syngas at a concentration sufficient to reduce the concentration downstream of one or more gasifiers, according to one or more embodiments described. Metal dusting in components.

detail

Systems and methods for maintaining sulfur concentration in syngas are provided. The method can include combining sulfur with a carbonaceous material to produce a sulfur-containing carbonaceous feedstock. The method may also include gasifying at least a portion of the carbonaceous feedstock comprising sulfur to generate syngas and detecting a sulfur concentration in the syngas. The method also includes adjusting the amount of sulfur combined with the carbonaceous material based on the detected sulfur concentration.

1 depicts a schematic diagram of an illustrative gasification system 100 that generates syngas via line 151 having a sulfur concentration sufficient to reduce metal dusting in components downstream of gasifier 150, according to one or more embodiments. The gasification system 100 may include one or more lock hoppers or storage hoppers 110, 130 for feeding one or more gasifier feed systems 140, wherein the gasifier feed may be fed into one or more The gasifier 150 is used for storage or processing prior to generating syngas. Elemental sulfur may be stored in one or more "first" lock hoppers or storage hoppers 110, which may be any component suitable for retaining and/or dispensing sulfur. One or more feeders 120 may distribute sulfur from first lock hopper 110 via line 122 to one or more "second" lock hoppers or storage hoppers 130 for storing gasified feedstock to combine sulfur with feedstock .

Although not shown, the feeder 120 can distribute the sulfur from the first lock hopper 110 onto and/or into a transport device, which can then transport or convey the sulfur to the second lock hopper 130. For example, the transport device may be a transport belt, a slide, a chute, an incline or a combination thereof. The transport means may further control the rate at which sulfur is dispensed to the second lock hopper 130 . For example, if the transport means is a conveyor belt, the speed of the belt may be adjusted to dispense sulfur slowly or rapidly, for example according to the amount of sulfur measured further down the system.

The second lock hopper 130 may receive, store and/or mix feedstock and sulfur so that carbonaceous material comprising sulfur may be obtained therein. Second hopper 130 may transport or distribute the sulfur-containing carbonaceous material to gasifier feed system 140 via line 131 . Preferably, the carbonaceous material comprising sulfur may be transported from second lock hopper 130 to gasifier feed system 140 via line 131 at a rate of at least 50 kilograms per hour (kg/h), and more Preferably, the rate of transport is from a low of about 75 kg/h, about 100 kg/h or about 125 kg/h to a high of about 450 kg/h, about 500 kg/h or about 550 kg/h. The second lock hopper 130 may include a feeder (not shown), such as a high pressure rotary feeder, which may cooperate with a stream of added fluid (not shown) to pass the sulfur containing carbonaceous material through the pipeline 131 is transported to the gasifier feed system 140.

As used herein, the term "feedstock" refers to one or more carbonaceous materials, whether solid, gaseous, liquid, or any combination thereof. The feedstock may comprise one or more carbonaceous materials (i.e., carbonaceous materials) including, but not limited to: biomass (i.e., plant and/or animal matter or substances), coal (i.e., high- and low-sodium lignite, brown coal, sub-bituminous coal, and/or anthracite), oil shale, coke, tar, asphaltenes, low-ash or ash-free polymers, hydrocarbon-based polymers, biomass Derived materials, by-products derived from manufacturing operations, or any combination thereof. The hydrocarbon-based polymer materials may include, but are not limited to: thermoplastics, elastomers, rubbers, including polypropylene, polyethylene, polystyrene, including other polyolefins, homopolymers, copolymers, block copolymers, PET (polyethylene terephthalate), polymer blends, oxygenated polyhydrocarbons, heavy hydrocarbon sludge and residual products from refineries and petrochemical plants, such as hydrocarbon waxes, their blends, their derivatives or any combination thereof.

The feedstock may comprise a mixture or combination of two or more low-ash or ash-free polymers, biomass-derived materials, or by-products derived from manufacturing operations. For example, the feedstock may include one or more carbonaceous materials combined with one or more discarded consumer products, such as carpet and/or plastic parts/components for automobiles, such as insurance bar or dashboard. If desired, these discarded consumer products may be reduced in size, such as by crushing prior to or during processing through the gasification system 100 . The feedstock may also include one or more recycled plastics, such as polypropylene, polyethylene, polystyrene, derivatives thereof, blends thereof, or any combination thereof. Thus, the gasification system 100 can be used to adjust the order to come before the proper processing of the produced substance.

The feedstock may be dried and then comminuted by one or more milling units (not shown) before being introduced into the second lock hopper 130 via line 101 . For example, the feedstock via line 101 can be dried from a high moisture limit of about 35% to a low moisture limit of about 18%. For example, a fluidized bed dryer (not shown) can be used to dry the feedstock passing through line 101.

The average particle size of the feedstock via line 101 can range from a low end of about 1 micron, about 10 microns, about 50 microns, about 100 microns, about 150 microns, or about 200 microns to a high end of about 1,350 microns, about 1,400 microns, about 1,450 microns, or about 1,500 microns. For example, the average particle size of the feedstock via line 101 can be from about 75 microns to about 1,475 microns, from about 125 microns to about 1,425 microns, or from about 175 microns to about 1,375 microns. In another example, the feedstock via line 101 can be ground to an average particle size of about 300 microns or less.

Gasifier feed system 140 may receive sulfur-containing carbonaceous material via line 131 to produce a first or “gasifier” feed via line 141 . Gasifier feed system 140 may provide a controlled flow of sulfur-containing carbonaceous material or carbonaceous feedstock into gasifier 150 via line 141 while accommodating pressure changes within gasifier 150 . The gasifier feed system 140 may include one or more lock vessels or storage hoppers, one or more distribution vessels, and/or one or more feeders connected by one or more valves.

Alternatively, the second lock hopper 130 may be bypassed and sulfur added directly to the gasifier feed system 140 via line 123 . In another example, instead of adding the sulfur via line 121 to the second lock hopper 130 or the gasifier feed system 140 , the sulfur via line 124 may be added to the gasifier feed in line 141 . In yet another example, the sulfur via line 124 can be added to the gasifier feed in line 141 and the sulfur via line 121 can be added to the second lock hopper 130 and/or the sulfur via line 123 can be added to the gasifier feed. The carburetor feed system 140. Although not shown, the sulfur added via line 124 may be pressurized to the pressure of the gasifier feed in line 141 and/or gasifier 150 prior to introduction into the gasifier feed in line 141 and/or gasifier 150 150 pressure.

The average particle size of the gasifier feed via line 141 can range from a low of about 1 micron, about 10 microns, about 50 microns, about 100 microns, or about 150 microns to a high of about 400 microns, about 450 microns, or about 500 microns. For example, the average particle size of the gasifier feed via line 141 can be from about 75 microns to about 475 microns, from about 125 microns to about 425 microns, or from about 250 microns to about 350 microns.

The gasifier feed via line 141 may be introduced into one or more gasifiers 150 to produce a raw syngas stream via line 151 . Gasifier 150 can gasify at least a portion of the gasifier feed introduced via line 141 to produce a raw syngas stream via line 151 . The gasifier feed via line 141 may be a dry feed or may be transported to gasifier 150 as a slurry or suspension. The sulfur concentration of the gasifier feed or sulfur-containing carbonaceous material in line 141 can be sufficient to generate a syngas via line 151 that reduces or prevents metal dusting in downstream processing equipment. For example, the sulfur concentration in the gasifier fed via line 141 may be in an amount sufficient to produce raw syngas via line 151 having a sulfur concentration by volume percent (vol %) of at least 0.1, at least 0.2vol% or at least 0.3vol%. The sulfur concentration of the raw syngas in line 151 may vary at least in part based on the amount of sulfur added to the second lock hopper 130 , the gasifier feed system 140 , and/or the gasifier feed via line 141 . For example, the sulfur concentration of the raw syngas in line 151 can be about 0.01 vol% or more, about 0.05 vol% or more, about 0.1 vol% or more, about 0.15 vol% or more, about 0.2 vol% or More, about 0.25vol% or more, about 0.3vol% or more, about 0.35vol% or more, about 0.4vol% or more, about 0.45vol% or more, about 0.5vol% or more , about 0.6 vol% or more, about 0.7 vol% or more, about 0.8 vol% or more, about 0.9 vol% or more, or about 1 vol% or more. In another example, the sulfur concentration of raw syngas stream 151 may be from about 0.1 vol% to about 0.4 vol%. Sulfur may be present in the form of hydrogen sulfide, carbonyl sulfide, and other sulfur-containing compounds.

The raw syngas in line 151 can also contain about 60 vol% or more of carbon monoxide and hydrogen, with additional components consisting primarily of carbon dioxide and methane. For example, the raw synthesis gas in line 151 can contain about 90 vol% or more carbon monoxide and hydrogen, about 95 vol% or more carbon monoxide and hydrogen, about 97 vol% or more carbon monoxide and hydrogen, or about 99 vol% or more carbon monoxide and hydrogen. In one example, the raw syngas in line 151 can have a carbon monoxide content ranging from a low of about 10 vol%, about 20 vol%, or about 30 vol% to a high of about 50 vol%, about 70 vol%, or about 85 vol%. In another example, the raw syngas in line 151 can have a carbon monoxide content ranging from a low of about 15 vol%, about 25 vol%, or about 35 vol% to a high of about 65 vol%, about 75 vol%, or about 85 vol%. The hydrogen content of the raw syngas in line 151 can range from a low of about 1 vol%, about 5 vol%, or about 10 vol% to a high of about 30 vol%, about 40 vol%, or about 50 vol%. For example, the hydrogen content of the raw syngas in line 151 can be from about 20 vol% to about 30 vol%.

The raw syngas in line 151 can comprise less than about 25 vol% or less, about 20 vol% or less, about 15 vol% or less, about 10 vol% or less, or about 5 vol% or less of a combination of nitrogen, methane , carbon dioxide, water, hydrogen sulfide and hydrogen chloride. The raw syngas in line 151 can have a carbon dioxide content of about 25 vol% or less, about 20 vol% or less, about 15 vol% or less, about 10 vol% or less, about 5 vol% or less, about 3 vol % or less, about 2vol% or less, or about 1vol% or less. The methane content of the raw syngas in line 151 can be about 15 vol% or less, about 10 vol% or less, about 5 vol% or less, about 3 vol% or less, about 2 vol% or less, or about 1 vol % or less. The raw syngas in line 151 can have a water content of about 40 vol% or less, about 30 vol% or less, about 25 vol% or less, about 20 vol% or less, about 15 vol% or less, about 10 vol % or less, about 5 vol% or less, about 3 vol% or less, about 2 vol% or less, or about 1 vol% or less. The raw syngas in line 151 can be nitrogen-free or substantially nitrogen-free, eg, containing about 0.5 vol% nitrogen or less.

The raw syngas in line 151 can have a calorific value corrected for heat loss and dilution effects from about 1,863 kJ/m ³ (50 Btu/scf) to about 2,794 kJ/m ³ (75 Btu/scf), from about 1,863 kJ/m ³ to about 3,726kJ/m ³ (100Btu/scf), about 1,863kJ/m ³ to about 4,098kJ/m ³ (110Btu/scf), about 1,863kJ/m ³ to about 5,516kJ/m ³ (140Btu/scf), About 1,863kJ/m ³ to about 6,707kJ/ ³ (180Btu/scf), about 1,863kJ/m ³ to about 7,452kJ/m ³ (200Btu/scf), about 1,863kJ/m ³ to about 9,315kJ/m ³ (250Btu/scf), about 1,863kJ/m ³ to about 10,246kJ/m ³ (275Btu/scf), 1,863kJ/m ³ to about 11,178kJ/m ³ (300Btu/scf), or about 1,863kJ/m ³ to About 14,904kJ/m ³ (400Btu/scf).

One or more analyzers 160 may be used to control the rate and amount of sulfur entering the gasifier 150 . The analyzer 160 can be used to detect or measure the amount of sulfur and/or sulfur compounds in the raw syngas, that is, the sulfur content or concentration, and can communicate with the feeder 120 and/or the first lock hopper 110 through the communication line 161 , to control the amount of gasifier feed added to the second lock hopper 130, the gasifier feed system 140, the gasifier feed in line 141 and/or injected directly into the gasifier feed to the gasifier 150 (not shown) Rate and/or amount of sulfur. The communication line 161 may be wired, wireless or a combination thereof. In another example, the analyzer 160 can alert personnel to the sulfur concentration in the raw syngas in line 151 and added to the second lock hopper 130, gasifier feed system 140, line 141 The gasifier feed and/or the rate and/or amount of sulfur injected directly into the gasifier feed to gasifier 150 (not shown) may be manually adjusted or controlled.

The analyzer 160 may be placed downstream of the gasifier 150, for example, across one or more coolers (not shown) and/or one or more particulate removal elements (not shown) to allow for detection or measurement of synthetic The syngas is cooled and/or the entrained solids are removed, respectively, prior to reducing the sulfur concentration in the gas. For example, once the syngas is cooled to about 600°C or less, about 500°C or less, about 450°C or less, about 400°C or less, about 350°C or less, about 300°C or less, The analyzer 160 can measure the sulfur concentration of the syngas at a temperature of about 250°C or less, about 200°C or less. In another example, the analyzer 160 may measure the sulfur concentration of the syngas once the syngas is cooled to a temperature of 350°C. In yet another example, once the level of particulates in the syngas is reduced to about 10 ppmw or less, about 5 ppmw or less, about 1 ppmw or less, about 0.3 ppmw or less, about 0.2 ppmw or less, or about 0.1 ppmw or lower, the analyzer 160 can measure the sulfur concentration of the syngas.

Analyzer 160 may be any analyzer or technology capable of estimating, detecting, or measuring the amount or concentration of sulfur or sulfur compounds in the syngas. For example, analyzer 160 may use gas chromatography, vapor chromatography, gas-liquid partition chromatography to detect, measure, or otherwise estimate the sulfur concentration in raw syngas stream 151 exiting gasifier 150 . Analyzer 160 can use flow-through narrow tubes or columns, in which the different chemical compositions of the samples, depending on their various chemical and physical properties and their interaction with specific column packings, are expressed in different ways in the gas stream or carrier gas. The rate passes through the flow-through narrow tube or column, and the specific column packing is called the stationary phase. The passage of the carrier gas may be referred to as the moving or mobile phase. The mobile phase may utilize a carrier gas including but not limited to an inert gas such as helium or a non-reactive gas such as nitrogen. Analyzer 160 may also be or include a spectrometer, laser spectrometer, meteorometer, gas separator, or any combination of the foregoing analytical devices or techniques.

Detectors that may be used in analyzer 160 include, but are not limited to: Flame Ionization Detector (FID), Thermal Conductivity Detector (TCD), Discharge Ionization Detector (DID), Electron Capture Detector (ECD), Flame Photometric detector (FPD), flame ionization detector (FID), Hall electrolytic conductivity detector (HECD), helium ionization detector (HID), nitrogen phosphorus detector (NPD), infrared detector (IRD), Mass selective detector (MSD), photoionization detector (PID), pulse amplification ionization detector (PDD), thermal energy (conductivity) analyzer/detector (TEA/TCD), mass spectrometer, infrared spectrophotometer, Nuclear Magnetic Resonance (NMR) spectrometers or their combination.

In operation, feeder 120 may be adjusted automatically and/or manually based on signals and/or data communicated in communication line 161 . The feeder 120 can be a metered feeder or a rotofeed dispenser, and can be driven by a variable speed motor (not shown) to adjust the sulfur feed rate and amount. Feeder 120 may be adjusted when analyzer 160 detects an insufficient amount of sulfur and/or sulfur compounds in the raw syngas in line 151, ie, the sulfur concentration is below a predetermined value or desired first or "lower" threshold to increase the rate at which sulfur via line 122 is distributed or transported to the gasifier feed in second lock hopper 130 , gasifier feed system 140 and/or line 141 . Insufficient sulfur in the raw syngas in line 151 refers to a sulfur concentration of less than about 0.1 vol % based on the total volume of the raw syngas in line 151 .

The feed may be adjusted automatically and/or manually when analyzer 160 detects excess sulfur and/or sulfur compounds in the raw syngas in line 151, ie, the sulfur concentration or concentration is above a desired second or "upper" threshold 120 to reduce the rate at which the sulfur via line 122 is distributed or transported to the gasifier feed system 140, the rate at which the sulfur is added to the gasifier feed system 140 via line 123, and/or the rate at which the sulfur is added to the gasifier feed system 140 via line 124 The rate at which sulfur is introduced into gasifier 150 via line 141. For example, when the sulfur concentration in the raw syngas in line 151 increases above about 0.4 vol%, about 0.5 vol%, about 0.6 vol%, about 0.7 vol%, about 0.8 vol%, about 0.9 vol%, or about 1 vol% , the amount of sulfur introduced into the second lock hopper 130, the gasifier feed system 140, and/or the gasifier feed in line 141 may be reduced and/or stopped. In this manner the sulfur concentration in the raw syngas stream 151 may be controlled automatically or manually to maintain the sulfur concentration within a predetermined or desired range to reduce or prevent metal dusting in components downstream of the gasifier 150 .

Considering gasifier 150 in more detail, gasifier 150 may be or include one or more circulating solids or transport gasifiers, one or more fixed bed gasifiers, one or more fluidized bed gasifiers, One or more entrained bed gasifiers or combinations thereof. For example, a circulating solids gasifier can be operated by introducing one or more oxidants into a feed stream, such as the gasifier feed via line 141, and/or into one or more mixing zones (not shown) to provide a gas mixture. In another example, the oxidant can be added directly to the gasifier. The type and amount of oxidant introduced into the circulating solids gasifier can affect the composition and physical properties of the syngas via line 151, and thus affect the downstream products produced therefrom. The one or more oxidizing agents described may be introduced into one or more mixing zones to form a gas mixture, and may be introduced, for example, at a rate suitable for controlling the temperature of the mixing zone. The gas mixture may move up through the mixing zone into a riser (not shown), where the riser residence time may allow char gasification, methane/steam formation, tar cracking, and/or water gas shift reactions to occur. The temperature of the mixing zone may start at about 500°C to about 650°C and increase to about 900°C, for example if ground coke or equivalent is fed into the mixing zone. In one example, the riser can operate at a higher temperature than the mixing zone. The gas mixture can exit the riser and enter one or more disengagers or cyclones (not shown) where large particulates can be separated from the gas and recycled back to the mixing zone.

The residence time in the circulating solids gasifier can be from about 2 seconds or more to about 10 seconds or more, where the temperature can be sufficient for the water gas shift reaction to reach equilibrium (i.e., a low limit of about 250°C to a high limit of about 1,000°C temperature). The operating temperature of the circulating solids gasifier can be controlled, at least in part, by the recirculation rate and residence time of the solids within the riser, by reducing the temperature of the ash prior to recirculation to the mixing zone, by adding steam to the mixing zone zone and/or by adding an oxidant to the mixing zone. Recycled solids can be used to rapidly heat the gasifier feed entering via line 141, which can minimize tar formation. The mixing zone may be operated at a pressure of about 100 kilopascals (kPa) to about 4500 kPa to increase heat output per unit reactor cross-sectional area and to increase energy output in any subsequent power cycle.

Since the outlet temperature of a circulating solids gasifier can be proportionally lower than a comparable gasifier (eg, slag type), the amount of heat in the syngas and the amount of chemical heat can be commensurately smaller in a circulating solids gasifier. Due to the reduced operating temperature in the gasifier (i.e. less than 1,600°C), less energy can be expended to control and optimize the H ₂ :CO ratio, allowing hydrogen to be added without an equivalent increase in steam demand in the gasifier output. Suitable circulating solids gasifiers may be as discussed and described in US Patent No. 7,722,690 and US Patent Application Nos. 02008/0155899, 2009/0151250, and 2009/0188165.

In another example, a fixed bed or moving bed gasifier can be operated by introducing the gasifier feed via line 141 into the upper or top (not shown) section of the reactor. Oxygen and/or steam may be introduced into the fixed bed gasifier located in the lower or bottom portion of the reactor. The feed can move down through the reactor by gravity and can be gasified. The remaining ash from the gasification can exit at the bottom of the reactor. Fixed bed gasifiers can operate at relatively low outlet temperatures (425°C to 700°C) and can require lower amounts of oxygen compared to fluidized bed gasifiers and entrained bed gasifiers, but have high steam requirements And produce a lot of tar. Fixed bed gasifiers can have limited capacity to handle fines and have particular demands on handling caking coals. The product syngas from the fixed bed gasifier may include unconverted methane and/or by-product tars and oils. Suitable fixed bed gasifiers may be as discussed and described in US Patent Nos. 4,290,780, 4,417,528, and 5,069,685 and US Patent Application No. 2008/0086945.

In yet another example, it can be operated by mixing feed from a gasifier via line 141 with older, partially gasified and/or fully gasified particles in a reactor (not shown) Fluidized bed gasifier. The gas can be used to fluidize the solid particles, and then the gas and remaining solid particles can be separated. The gas in the reactor may include oxygen, steam, recycled syngas, or combinations thereof. The flow of gas into the reactor may be sufficient to levitate the solid particles without sucking the solid particles out of the reactor. Fluidized bed gasifiers can operate at moderate outlet temperatures, and the temperature can be consistent throughout the bed. For example, the fluidized bed gasifier can be operated at a temperature ranging from a low of about 700°C, about 750°C, about 800°C, about 850°C to a high of about 1,000°C, about 1,050°C, about 1,100°C, or about 1,150°C. A fluidized bed gasifier may require a larger amount of oxygen than a comparable fixed bed gasifier but a smaller amount of oxygen than a comparable entrained bed gasifier. Likewise, a fluidized bed gasifier may require less steam than a comparable fixed bed gasifier but more steam than a comparable entrained bed gasifier. Syngas from a fluidized bed gasifier may be of higher purity and carbon conversion may be lower than from a comparable entrained bed gasifier. Purity can be measured by the amount of H ₂ +CO in the syngas. For example, the purity of the syngas in the fluidized bed gasifier can be 25% to 90% _H2 +CO. The carbon conversion in the fluidized bed gasifier can be, for example, from a low of about 92%, about 93%, or about 94% to a high of about 97%, about 98%, or about 99%. Suitable fluidized bed gasifiers may be as discussed and described in US Patent Nos. 4,696,678, 6,972,114, and 7,503,945 and US Patent Application No. 2008/0250714.

In yet another example, the entrained bed gasifier can be operated by injecting the gasifier feed via line 141 with the oxidant in parallel streams into the reactor bed. The gasifier feed heats up rapidly and reacts with the oxidant. The oxidant may be oxygen, steam, recycled syngas or combinations thereof. Entrained bed gasifiers may require large amounts of oxidant and may require high oxygen purity. For example, an entrained bed gasifier may require about 0.2 standard cubic meters (“Nm ³ ”) of O ₂ to about 0.5 Nm 3 ) of O ₂ per Nm ³ (H ₂ +CO). Additionally, the introduction into an entrained bed gasifier The oxidant of the entrained bed gasifier can have a purity of about 99.5% or higher. Entrained bed gasifiers can operate at high temperatures and often require high temperatures to achieve high carbon conversion. For example, entrained bed gasifiers can operate at low limits of about 1,150°C, about 1,200°C, about 1,250°C, or about 1,300°C up to about 1,550°C, about 1,600°C, about 1,650°C, or about 1,700°C. Entrained bed gasifiers may also require higher Higher energy input in the form of higher steam and/or oxygen consumption rates. Entrained bed gasifiers can obtain high purity syngas and can gasify a wide range of materials. For example , the syngas from the entrained bed gasifier can have less than about 0.5% N ₂ , no tar, and a few parts per million of methane. The entrained bed gasifier can have a short residence time, i.e., a low limit of about 0.1 seconds, From about 0.2 seconds or about 0.3 seconds to a high limit of about 1 second, about 2 seconds or about 3 seconds. Suitable entrained bed gasifiers may be as described in U.S. Patent Nos. 4,158,552, 4,531,949, and 5,620,487 and U.S. Patent Application No. discussed and described in .

Figure 2 depicts a schematic diagram of another illustrative gasification system 200 for producing syngas via line 251 having a sulfur concentration sufficient to reduce Metal dusting in components downstream of the gasifier (one shown at 250). Similar to the embodiment discussed and described above with reference to FIG. 1 , sulfur may be stored in one or more first lock or storage hoppers 110 . The first lock hopper 110 may be in communication with a first or “sulfur” feeder 220 either directly or via line 111 . First feeder 220 may distribute sulfur from first lock hopper 110 to one or more second lock hoppers 130 via lines 221 and 222 . First feeder 220 may control the amount and/or rate of sulfur distributed to second lock hopper 130 via line 221 . For example, the first feeder 220 may be a metered feeder or a rotary propulsion dispenser, and may be driven by a variable speed motor (not shown). Before being fed into the first lock hopper 110 and/or the first feeder 220, the sulfur may be pulverized or ground into a powder and after pulverization the average particle size may be as described above with reference to FIG. 1 The dimensions of the first lock hopper 110 and the feeder 120 are discussed and described.

Second lockhopper 130 may receive, store, and/or mix feedstock via line 101 with sulfur via line 222 and may transport or distribute sulfur-containing carbonaceous material via line 239 to gasifier feed system 240 . Alternatively, sulfur may be added directly to the gasifier feed system 240 , bypassing the second lock hopper 130 . For example, sulfur via line 223 may be added to one or more storage hoppers 242 of gasifier feed system 240 instead of sulfur being added to second lock hopper 130 via lines 221 and 222 .

The second lock hopper 130 can be operated via line 231 in conjunction with a second feeder 234, such as a high pressure rotary feeder in cooperation with added fluid steam (not shown) to feed the carbonaceous material Transported via line 239 to gasifier feed system 240 . Exemplary fluids may include, but are not limited to, air, nitrogen, carbon dioxide, or any combination thereof. Preferably, the carbonaceous material may be transported from the second lock hopper 130 to the gasifier feed system 240 at a rate of at least 10,000 kg/h and more preferably at a rate of about 20,000 kg/h up to about 30,000 kg/h .

Gasifier feed system 240 may accept sulfur-containing carbonaceous material via line 239 and/or from another process or source (not shown) and generate a gasifier feed via line 241 . The gasifier feed system 240 may include a storage hopper 242, one or more first or "lock" vessels 244, one or more second or "distribution" vessels 246, and one or more second feed Feeder 248. The storage hopper 242 may be connected to and/or in fluid communication with the lock container 244 via one or more first control valves 243, and the storage hopper 244 may be connected to and/or in fluid communication with the lock container 244 via one or more second control valves 245. and/or in fluid communication with dispensing container 244 .

Carbonaceous material from second lock hopper 130 may be introduced to storage hopper 242 via line 239 and any additional sulfur via line 223 . Nitrogen may be added to storage hopper 242 via low pressure nitrogen source 202 to maintain the air pressure within storage hopper 242 . The sulfur added to the storage hopper 242 may be mixed with the carbonaceous material in the storage hopper 242 to provide sulfur-containing carbonaceous material in the lock vessel 244 and/or the distribution vessel 246 .

The carbonaceous material via line 239 may or may not have added sulfur and may be dried and/or comminuted. For example, the carbonaceous material via line 101 may be dried and may be comminuted by one or more pulverizers (not shown) before being fed to second lock hopper 130 . For example, the feedstock via line 101 can be dried to about 22% to about 15% moisture. In another example, the feedstock via line 101 can be dried to about 18% moisture. In one or more embodiments, a fluidized bed dryer (not shown) can be used to dry the feedstock via line 101 . Carbonaceous material via line 239 may be dried and may be comminuted by one or more pulverizers (not shown) before being fed to storage hopper 242 . The mill may include, for example, one or more bowl mills or one or more rod mills (not shown).

Sulfur-containing carbonaceous material from storage hopper 242 may be fed into lock vessel 244 at a controlled rate or intermittently. The lock container 244 can be separated from the storage hopper 242 by closing the first control valve 243 . The lock vessel 244 may be pressurized to a first or "full system" pressure using the first high pressure nitrogen source 203 .

The first pressure in the lock-off vessel 244 can range from a low of about 2,400 kPa, about 2,600 kPa, about 2,800 kPa, or about 3,000 kPa to a high of about 4,000 kPa, about 4,200 kPa, about 4,400 kPa, or about 4,600 kPa. For example, the first pressure in lock-off vessel 244 may be from about 2,500 kPa to about 4,500 kPa, from about 2,700 kPa to about 4,300 kPa, or from about 2,900 kPa to about 4,100 kPa. In another example, the first pressure may be about 3,500 kPa. Dispensing container 246 may be maintained at a first pressure.

Once the sulfur-containing carbonaceous material in the lock vessel 244 reaches the first pressure, ie the pressure of the dispensing vessel 246 , a second control valve 245 between the lock vessel 244 and the dispensing vessel 246 may be opened. The sulfur-containing carbonaceous material may then be gravity fed into dispensing vessel 246 until the entire inventory of lock vessel 244 is drained into dispensing vessel 246 . The lockout vessel 244 may then be separated from the dispensing vessel 246 and depressurized in preparation to receive another discharge of sulfur-containing carbonaceous material from the storage hopper 242 .

Dispensing container 246 may operate continuously at the first pressure. The pressure in dispensing vessel 246 may be maintained using nitrogen through second high pressure nitrogen source 204 . Sulfur-containing carbonaceous materials may be transported from the bottom of distribution vessel 246 to one or more gasifiers 250 via second feeder 248 .

The second feeder 248 may be a non-mechanical feed control device with no moving parts and may combine a continuous ash depressurization system with conventional designs for flow rate control. The driving force for the flow of sulfur-containing carbonaceous material in feeder 248 may be a pressure differential therein. Nitrogen gas via third high-pressure nitrogen source 205 and transport fluid, such as air and/or recycled syngas, via transport fluid source 206 may contribute to the inclusion of the gas passing through feeder 248 and exiting feeder 248 to gasifier 250. The flow rate of sulfur carbonaceous material is metered.

Gasifier feed via line 241 may be introduced to gasifier 250 to generate raw syngas stream 251 . The gasifier feed in line 241 can be a dry feed or transported to the gasifier as a slurry or suspension. Gasifier 250 may be, but is not limited to, one or more circulating solids gasifiers, one or more fixed bed gasifiers, one or more fluidized bed gasifiers, one or more entrained bed gasifiers or a combination of them.

The gasifier 250 may include a single reactor train or two or more reactor trains arranged in series or parallel. Each reactor train may include one or more mixing zones 252 , one or more risers 253 , and one or more settlers 254 . Each reactor train may be configured independently of each other or may be configured to share any one or more of mixing zone(s) 252 , riser 253 or settler 254 . For simplicity and ease of description, embodiments of gasifier 250 will be further described in the context of a single reactor train.

The gasifier feed via line 241 and the one or more oxidants or process air via line 214 can be combined in mixing zone 252 to provide a gas mixture or suspension. As shown, the gasifier feed via line 241 and the oxidant via line 214 can be injected into mixing zone 252 separately or mixed (not shown) prior to injection into the mixing zone. For example, gasifier feed via line 241 and oxidant via line 214 can be injected into gasifier 250 sequentially. In another example, gasifier feed via line 241 and oxidant via line 214 can be injected into gasifier 250 at the same time.

The type and amount of oxidant introduced to gasifier 250 via line 214 can affect the composition and physical properties of the syngas via line 251 and thus affect the downstream products produced therefrom. The one or more oxidants may include, but are not limited to: air, oxygen, essentially oxygen, oxygen-enriched air, mixtures of oxygen and air, oxygen and inert gases such as nitrogen and argon mixture etc. The oxidizing agent may comprise about 65 vol % oxygen or more, about 70 vol % oxygen or more, about 75 vol % oxygen or more, about 80 vol % oxygen or more, about 85 vol % oxygen or more, about 90 vol % oxygen or more, about 95 vol% oxygen or more, or about 99 vol% oxygen or more. As used herein, the term "substantially oxygen" refers to an oxygen stream comprising 51 vol% oxygen or more. As used herein, the term "oxygen-enriched air" refers to air containing 21 vol% oxygen or more. Oxygen-enriched air may be obtained, for example, from cryogenic distillation of air, pressure swing adsorption, membrane separation, or any combination thereof. At least one of the oxidants may be pure oxygen supplied by one or more air separation units (not shown). The one or more oxidizing agents may be nitrogen-free or substantially nitrogen-free. By "substantially free of nitrogen", it is meant that the one or more oxidants comprise about 5 vol% nitrogen or less, about 4 vol% nitrogen or less, about 3 vol% nitrogen or less, about 2 vol% nitrogen or less or about 1 vol% nitrogen or less.

The gas mixture may move up through mixture 252 into riser 253 where the additional residence time allows for char gasification, methane/steam formation, tar cracking, and/or water gas shift reactions to occur. Riser 253 may operate at a higher temperature than mixing zone 252 and may have a smaller diameter than mixing zone 252 . Suitable temperatures in riser 253 may range from a low of about 700°C, about 715°C, about 730°C, or about 750°C to a high of about 950°C, about 1,000°C, about 1,050°C, or about 1,100°C. For example, suitable temperatures in riser 253 may be from about 710°C to about 1,075°C, from about 720°C to about 1,025°C, or from about 740°C to about 975°C. The superficial gas velocity in the riser 253 can range from a low of about 3 meters per second (m/s), about 6 m/s, or about 9 m/s to a high of about 21 m/s, about 24 m/s, or about 27 m/s. For example, the superficial gas velocity in riser 253 may be from about 5 m/s to about 25 m/s, from about 10 m/s to about 18 m/s, or from about 9 m/s to about 12 m/s.

The gas mixture may exit the riser 253 and enter a settler 254 where larger particles may be separated from the gas and circulated back to the mixing zone 252 through one or more conduits, including but not limited to: Standpipe 259 and/or j-leg 258 . The j-bracket 258 may include a non-mechanical “j-valve” to increase the effective solids residence time, improve carbon conversion and minimize aeration requirements for solids recirculation to the mixing zone 252 . In one or more embodiments, the settler 254 can be a cyclone separator. One or more particle transfer devices 257, such as one or more loop seals or seal legs, can be placed downstream of the settler 254 for collecting the separated particle powder. ). Although not shown. A second stage solids settler or cyclone separator may be placed or placed on standpipe 259 for separating most of the fine solids from the top of settler 254 . Any entrained or residual particulates in the raw syngas stream 251 may be removed using one or more particulate removal systems or particulate control devices 290 . Recycle gas via line 208, eg, from a compressor (not shown), may be fed to j-rack 258, particle transporter 257, standpipe 259, or any combination thereof for aeration to aid solids circulation.

One or more oxidants may be introduced into the bottom of mixing zone 252 via line 214 to increase the temperature of mixing zone 252 and riser 253 and to burn recirculated particulates contained in ash ("char") any carbon. For example, one or more oxidizing agents may be introduced into mixing zone 252 at a rate suitable for controlling the temperature of mixing zone 252 . The one or more oxidizing agents may include excess air. For example, the one or more oxidizing agents may be substoichiometric air, wherein the molar ratio of oxygen to carbon may be maintained at a substoichiometric concentration thereby favoring the formation of carbon monoxide over carbon dioxide in mixing zone 252 . In another example, the oxygen provided to the mixing zone 252 by the oxidant may be less than 5% of the stoichiometric amount of oxygen required to complete the combustion of all the carbon provided to the mixture 252 . Additional oxygen and steam in the air can be consumed by the char in the recycled solids to stabilize the reactor temperature during operation and during feed interruptions.

The residence time and temperature within the gasifier 250 may be sufficient to allow the water gas shift reaction to reach equilibrium. For example, the residence time of the gasifier feed via line 241 in mixing zone 252 can be greater than about 2 seconds, greater than about 5 seconds, or greater than about 10 seconds. The operating temperature of the gasifier 250 may range from a low of about 600°C, about 650°C, or about 700°C to a high of about 900°C, about 1,000°C, or about 1,100°C. For example, the operating temperature of gasifier 250 may be from about 625°C to about 1,050°C, from about 675°C to about 1,025°C, or from about 700°C to about 975°C.

The gasifier 250 may operate within a temperature range sufficient not to melt the ash, such as about 565°C to about 1040°C or about 840°C to about 930°C. Heat may be provided by combusting carbon in the recycle solids in the lower portion of mixing zone 252 before the recycle solids contact the gasifier feed via line 241 . The temperature of mixing zone 252 can be further increased to about 900° C. by bringing mixing zone 252 to a temperature of about 500° C. to about 650° C. °C to start up.

Startup burner 215 may be used to start up gasifier 250 via line 216 . Fuel for priming combustor 215 may be supplied via a priming fuel line via line 233 . Oxidant or process air for starting burner 215 may be supplied via line 214 . The start-up burner 215 may be a direct propane fired burner operative to heat the gasifier 250 to about 500°C to about 650°C. Liquid fuels, such as gasoline, may also be used based on their availability. The start-up burner 215 can be started at a system pressure of about 500 kPa to about 550 kPa and can be operated at a pressure of about 950 kPa to about 1,050 kPa.

Temperature changes in the gasifier 250 may be dampened by the large amount of solids circulating in the gasifier 250 . The recycled solids can also be used to rapidly heat the gasifier feed introduced via line 241, which can minimize tar formation.

The mixing zone 252 can be operated at a pressure of about 100 kPa to about 4500 kPa to increase the heat output per unit area of the reactor cross-section and to increase the energy output in any subsequent power cycle. For example, mixing zone 252 may operate at a pressure of about 250 kPa to about 4000 kPa, 500 kPa to about 3000 kPa, or about 750 kPa to about 2500 kPa.

The raw syngas in line 251 produced in gasifier 250 may be similar to the raw syngas in line 151 discussed and described above with reference to FIG. 1 . Steam may be added to the mixing zone of the gasifier along with the oxidant stream via line 214 to moderate the temperature rise at the point of oxidant introduction. Steam may also be provided to the mixing zone of the gasifier 250 to control the ratio of hydrogen to carbon monoxide (H ₂ :CO) within the gasifier 250 . Since the outlet temperature of gasifier 250 can be proportionally lower than that of comparable gasifiers (eg, slag type), the amount of heat and chemical heat in the raw syngas via line 251 can be reduced in gasifier 250 relatively small. Steam can be used to adjust the _H2 :CO ratio by using less energy consumption than other entrained bed gasifiers operating at higher temperatures. Due to the reduced operating temperature (i.e., less than 1,600°C) within the gasifier 250, less energy can be expended to control and optimize the _H2 :CO ratio without a commensurate increase in steam demand within the gasifier 250 case, increase the production of hydrogen. Leaving gasifier 250, the _H2 :CO of the raw syngas via line 251 can be from about 0.6:1 to about 1.3:1. For example, the ratio of _H2 :CO can be from about 0.7:1 to about 1.2:1, from about 0.8:1 to about 1.1:1, or from about 0.9:1 to about 1:1.

A gasifier bottom blowdown tank 255 may be used to de-inventory ash from the gasifier 250 during preventive repairs. Other accumulated ash in standpipe 259 may be removed from a particulate transfer device, such as a gate valve, to maintain ash levels within standpipe 259 . Solids from gasifier bottom blowdown tank 255 may be fed via line 256 for storage and/or treatment.

The raw syngas in line 251 can exit the gasifier at a temperature from about 575°C to about 1,050°C. One or more coolers 270 (“primary coolers”) may be used to cool the raw syngas in line 251 prior to entering particulate removal system 290 to provide cooled raw syngas stream 286 .

Cooler 270 may include one or more heat exchangers or heat exchange zones arranged in series (three shown: 271 , 280 and 285 ). The raw syngas in line 251 may be cooled by indirect heat exchange in first heat exchanger ("first zone") 271 to a temperature of about 260°C to about 820°C. The cooled raw syngas exiting first heat exchanger 271 via line 272 may be further cooled by indirect heat exchange in second heat exchanger ("second zone") 280 to a temperature of about 260°C to about 705°C. The cooled raw syngas exiting second heat exchanger 271 via line 282 may be further cooled to a temperature of about 260°C to about 430°C by indirect heat exchange in third heat exchanger ("third zone") 285.

A heat transfer medium may be used to cool the raw syngas in line 251 . The heat transfer medium may be saturated steam, boiler feed water and the like. Heat transfer medium via line 283 may be introduced into syngas cooler 270 . Heat from the raw syngas may be transferred indirectly to a heat transfer medium to provide superheated or high pressure superheated steam which may be recovered via line 281 . The superheated or high pressure superheated steam via line 281 may be used to power one or more steam turbines (not shown), which may drive, for example, a direct coupled electric generator (not shown). Condensate recovered from the steam turbine can be recycled as boiler feed water to cool the syngas and generate steam.

The heat transfer medium via line 283 may be heated in a third heat exchanger (“economizer”) 285 to provide cooled syngas via line 286 and boiler feed water via line 287 . Boiler feed water via line 287 may be saturated or substantially saturated under process conditions. Boiler feed water via line 287 may be introduced ("flashed") into one or more steam drums or separators 275 to provide heated water via line 277 for feeding to steam generator 271 middle.

The temperature of the superheated or high pressure superheated steam from syngas cooler 270 via line 281 can be about 400°C or higher, 425°C or higher, 450°C or higher, 475°C or higher, 500°C or higher Or 550°C or higher. The pressure of the superheated or high pressure superheated steam via line 281 can be 4,000 kPa or higher, about 4,500 kPa or higher, about 5,000 kPa or higher, about 5,550 kPa or higher, about 6,000 kPa or higher, about 6,500 kPa or higher, about 7,000 kPa or higher, or about 7,500 kPa or higher.

Boiler feed water via line 277 from separator 275 can be introduced into first heat exchanger ("steam generator") 271 and heat the raw syngas in line 251 to generate Separator 275 steam. Steam returned to separator 275 via line 273 may exit via line 276 for superheating in second heat exchanger 280 to provide superheated or high pressure superheated steam via line 281 which is One or more steam turbines (not shown) are used. The accumulation of solids in separator 275 can be controlled by blowing down a small amount of water through line 278.

Any or all of the heat exchangers 271, 280, 285 (three shown) may be shell and tube heat exchangers. The raw syngas in line 251 may be continuously fed to the shell side or the tube side of the first heat exchanger 271 , the second heat exchanger 280 and the third heat exchanger 285 . Depending on which pass the raw syngas is introduced to, the heat transfer medium can pass either the shell side or the tube side. In one or more embodiments, the raw syngas in line 251 can be fed in parallel to the shell side or the tube side of the first heat exchanger 271, the second heat exchanger 280, and the third heat exchanger 285 and according to Which side the raw syngas is introduced to, the heat transfer medium can pass through the shell side or the tube side continuously. Make-up heat transfer medium can be added via line 283 .

The cooled syngas via line 286 can be introduced to a particulate removal system 290 to partially or completely remove particulates from the cooled syngas to provide separated, "particulate-lean" via line 291 Or “clean” syngas, separated particulates via line 292 and condensate via line 293 . During start-up, steam via line 288 may be provided to particulate removal system 290 to preheat it. Although not shown, the one or more particulate removal systems 290 may optionally be used to partially or completely remove particulates from the raw syngas in line 251 prior to cooling. For example, the raw syngas in line 251 can be introduced directly to particulate removal system 290, resulting in hot gas particulate removal (eg, from about 550°C to about 1,050°C). Although not shown, two particle removal systems 290 may be used. For example, one particulate removal system 290 may be upstream of cooler 270 and one particulate removal system 290 may be downstream of cooler 270 .

One or more particulate removal systems 290 may include one or more separation devices, such as conventional separators and/or cyclones (not shown). A particulate control device ("PCD") capable of providing an outlet particulate concentration below the detectable limit of about 0.1 ppmw may also be used. Illustrative PCDs may include, but are not limited to: sintered metal filters, metal filter candles, and/or ceramic filter candles (eg, iron aluminide filter material). A small amount of high pressure recycle syngas via line 289 can be used to pulse clean the filters as they can accumulate particulates from the unfiltered syngas.

One or more analyzers (two shown 260 , 265 ) may be placed downstream of the gasifier 250 to measure the amount or concentration of sulfur exiting the gasifier 250 . Analyzers 260, 265 may be in communication with first feeder 220 and/or first lock hopper 110 via communication links 261, 266 and/or 267 to facilitate control and/or maintenance of gasifier 250 and/or raw syngas flow Sulfur concentration in 251. The communication devices 261, 266 and/or 267 may be wired, wireless or a combination thereof.

The temperature is cool enough to be sent to a tempering system (not shown), and the sulfur concentration at a point upstream of any treatment system that would alter the sulfur concentration of the syngas can be measured by analyzers 260, 265 downstream of the gasifier 250, so The treatment system described above is, for example, an alkaline washing step. For example, first analyzer 260 may measure the sulfur concentration in the cooled syngas via line 286 after it has been cooled by cooler 270 . In another example, the second analyzer 265 can measure the sulfur concentration in the separated syngas via line 291 after it passes through the particulate removal system 290 . In yet another example, the first analyzer 260 can measure the sulfur concentration in the cooled syngas via line 286 and the second analyzer 265 can measure the sulfur concentration in the separated syngas via line 291 . Analyzers 260, 265 can be, but are not limited to: gas chromatographs, meteorological instruments, gas separators, or any combination thereof. The analyzers 260, 265 may be the same as or similar to the analyzer 160 discussed and described above with reference to FIG. 1 .

Once the analyzers 260, 265 measure or determine the sulfur concentration in the cooled syngas via line 286 and/or the separated syngas via line 291, the analyzers 260, 265 can communicate via communication means 261, 266 and/or 267 Signals and/or data are output to an operator (not shown), first feeder 220 and/or first lock hopper 110 . For example, first analyzer 260 may communicate with first feeder 220 and/or first lock hopper 110 via communication devices 261 and 267 . In another example, second analyzer 265 may communicate with first feeder 220 and/or first lock hopper 110 via communication devices 266 and 267 . In yet another example, both analyzers 260 , 265 can communicate with the feeder via communication devices 261 , 266 and/or 267 . Although not shown, communication and actuation of first feeder 220 and/or first lock hopper 110 may be facilitated by an operator and/or control unit that may be connected to system 200 local or remote.

In operation, the first feeder 220 may be adjusted based on signals and/or data transmitted by the communication device 267 . When the first analyzer 260 and/or the second analyzer 265 detect an insufficient amount of sulfur in the cooled syngas via line 286 and/or the separated syngas via line 291, ie, the sulfur concentration is lower than desired concentration, the first feeder 220 can be adjusted to increase the rate at which sulfur is distributed or transported via line 222 to the gasifier feed system 240 and/or to increase the rate at which sulfur is distributed to the gasifier feed system via line 223 The rate of storage hopper 242 of 240. A sulfur deficit in the cooled syngas via line 286 can be defined as a sulfur concentration of less than about 0.05 vol%, about 0.1 vol%, or about 0.2 vol%, based on the total volume of the cooled syngas in line 286. A sulfur deficit in the separated syngas via line 291 can be defined as a sulfur concentration of less than about 0.05 vol%, about 0.1 vol%, or about 0.2 vol%, based on the total volume of the separated syngas in line 291.

When the analyzers 260, 265 detect excess sulfur in the cooled syngas via line 286 and/or the separated syngas via line 291, that is, when the sulfur concentration is too high, the first feeder 220 can be adjusted to reduce The rate at which sulfur via line 222 is distributed or transported to lock hopper 130 and/or the rate at which sulfur via line 223 is distributed to storage hopper 242 of gasifier feed system 240 is reduced. For example, when the sulfur concentration in the cooled syngas via line 286 increases to about 0.3 vol%, about 0.4 vol%, or about 0.5 vol%, about 0.6 vol%, about 0.7 vol%, about 0.8 vol%, about 0.9 vol% At or above about 1 vol%, the amount of sulfur distributed to the lock hopper 130 and/or the gasifier feed system 240 may be reduced or stopped. In another example, when the sulfur concentration in the separated syngas via line 291 is increased to about 0.3 vol%, about 0.4 vol%, or about 0.5 vol%, about 0.6 vol%, about 0.7 vol%, about 0.8 vol%, Above about 0.9 vol % or about 1 vol %, the amount of sulfur distributed to the lock hopper 130 and/or the gasifier feed system 240 may be reduced or stopped.

All adjustments to the first feeder 220 may be automatic adjustments based on the sulfur concentration (or concentrations) detected by the analyzers 260, 265. In another example, adjustments may be actuated by a controller (not shown) that receives one or more signal and/or data. The amount of sulfur dispensed through the first feeder 220 may also be manually adjusted based on signals and/or data sent by the analyzers 260 , 265 .

Embodiments of the present disclosure further relate to any one or more of the following paragraphs:

1. A method for maintaining a sulfur concentration in a synthesis gas, the method comprising: combining sulfur with a carbonaceous material to produce a carbonaceous feedstock comprising sulfur; gasifying at least a portion of the sulfur concentration in the synthesis gas; and Based on the detected sulfur concentration, the amount of sulfur added to the carbonaceous material is adjusted.

2. The method of paragraph 1, wherein the carbonaceous material comprises coal, coke, petroleum, biomass, or any combination thereof.

3. The method of paragraph 1 or 2, wherein the synthesis gas has a desired sulfur concentration of at least 0.1 vol%.

4. The method of any of paragraphs 1 to 3, wherein the carbonaceous material has an average particle size of from about 50 microns to about 500 microns.

5. The method of paragraph 4, wherein the added sulfur has an average particle size of from about 50 microns to about 500 microns.

6. The method of any of paragraphs 1 to 5, wherein the sulfur is detected using gas chromatography, spectrometry, vapor chromatography, gas-liquid partition chromatography, or a combination thereof.

7. The method of paragraph 6, wherein the carbonaceous mixture comprising sulfur has an average particle size of about 400 microns or less.

8. The method of any of paragraphs 1 to 7, wherein the sulfur-containing carbonaceous feedstock is gasified in a transport gasifier.

9. The method of any of paragraphs 1 to 7, wherein the carbonaceous feedstock comprising sulfur is gasified in a fluidized bed gasifier.

10. The method of any of paragraphs 1 to 7, wherein the carbonaceous feedstock comprising sulfur is gasified in an entrained bed gasifier.

11. The method of any of paragraphs 1 to 7, wherein the carbonaceous feedstock comprising sulfur is gasified in a fixed bed gasifier.

12. A method for maintaining a sulfur concentration in synthesis gas, the method comprising: adding sulfur to a carbonaceous material to produce a sulfur-containing carbonaceous feed, the carbonaceous feed comprising at least 0.05 vol% sulfur; introducing a sulfur-containing carbonaceous feed into a transport gasifier to generate syngas; detecting the sulfur concentration in the syngas; and adjusting the amount of sulfur added to the carbonaceous material based on the detected sulfur concentration to The sulfur concentration in the gas is maintained at about 0.1 vol% or higher.

13. The method of paragraph 12, further comprising increasing the amount of sulfur added to the carbonaceous material when the sulfur concentration in the syngas is below 0.1 vol%.

14. The method of paragraph 12 or 13, further comprising reducing the amount of sulfur added to the carbonaceous material when the sulfur concentration in the syngas is above 0.4 vol%.

15. A method for maintaining a sulfur concentration in synthesis gas, the method comprising: adding sulfur to a carbonaceous material at a controlled rate to produce a carbonaceous mixture comprising sulfur, wherein the first feeder regulates a controlled sulfur rate; introducing a sulfur-containing carbonaceous mixture into a feed system to generate a sulfur-containing carbonaceous feed; introducing the sulfur-containing carbonaceous feed into a gasifier at sufficient Operate under the conditions of generating syngas with a sulfur concentration of about 0.1vol% to about 0.4vol%; detect the sulfur concentration in the syngas; when the sulfur concentration is below 0.1vol%, adjust the first feeder to increase the sulfur addition the rate of sulfur into the carbonaceous material; and adjusting the first feeder to reduce the rate of sulfur added to the carbonaceous material when the sulfur concentration is above 0.4 vol%.

16. The method of paragraph 15, further comprising: changing the pressure of the sulfur-containing carbonaceous material from atmospheric pressure to the gasifier operating pressure.

17. The method of paragraph 15 or 16, wherein the gasifier operates at a temperature of from about 700°C to about 1,000°C.

18. The method of any of paragraphs 15 to 17, further comprising introducing the syngas to one or more coolers to generate cooled syngas, wherein after cooling the syngas, detecting the Sulfur concentration in the syngas.

19. The method of claim 18, further comprising introducing the cooled syngas to a particulated control device to partially or completely remove particulates from the cooled syngas to produce particulate-depleted syngas and separated particulates; using a second analyzer to detect the sulfur concentration in the particulate-lean syngas; when the sulfur concentration in the particulate-lean syngas is below a first threshold, adjust the metering feeder to increase the addition of sulfur to the carbon and adjusting the metering feeder to reduce the rate at which sulfur is added to the carbonaceous material when the sulfur concentration in the particulate-lean syngas is above a second threshold.

20. The method of any of paragraphs 15 to 19, wherein the gasifier operates at a pressure of from about 750 kPa to about 2,500 kPa.

Certain embodiments and features have been described using a set of numerical upper limits and a set of numerical lower limits. It is understood that ranges from any lower limit to any lower limit are contemplated unless otherwise indicated. Certain lower limits, upper limits and ranges appear in one or more claims below. All numerical values are "about" or "approximately" the indicated value, and take into account experimental error and variation that would be expected by one of ordinary skill in the art.

Various terms have been defined above. To the extent a above undefined term is used in a claim, it should be given the broadest definition persons in the pertinent art have given that term as reflected in at least one printed publication or issued patent. Furthermore, all patents, test procedures, and other documents cited in this application are fully incorporated by reference to the extent that such disclosure is not inconsistent with this application and in all jurisdictions in which such incorporation is permitted.

While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure can be conceived without departing from the essential scope of the present disclosure, which is defined by the following claims .

Claims (20)

1. A method for maintaining sulfur concentration in synthesis gas, said method comprising: Combining sulfur with carbonaceous materials to produce a carbonaceous feedstock comprising sulfur; gasifying at least a portion of the carbonaceous feedstock comprising sulfur to produce synthesis gas; detection of sulfur concentrations in syngas; and Based on the detected sulfur concentration, the amount of sulfur combined with the carbonaceous material is adjusted. 2. The method of claim 1, wherein the carbonaceous material comprises coal, coke, petroleum, biomass, or any combination thereof. 3. The method of claim 1, wherein the syngas has a sulfur concentration of at least 0.1 vol%. 4. The method of claim 1, wherein the carbonaceous material has an average particle size of about 50 microns to about 500 microns. 5. The method of claim 4, wherein the sulfur has an average particle size of from about 50 microns to about 500 microns. 6. The method of claim 1, wherein sulfur is detected using gas chromatography, spectrometry, gas chromatography, gas-liquid partition chromatography, or a combination thereof. 7. The method of claim 6, wherein the sulfur-containing carbonaceous mixture has an average particle size of about 400 microns or less. 8. The method of claim 1, wherein the sulfur-containing carbonaceous feedstock is gasified in a transport gasifier. 9. The method of claim 1, wherein the sulfur-containing carbonaceous feed is gasified in a fluidized bed gasifier. 10. The method of claim 1, wherein the carbonaceous feedstock comprising sulfur is gasified in an entrained bed gasifier. 11. The method of claim 1, wherein the carbonaceous feedstock comprising sulfur is gasified in a fixed bed gasifier. 12. A method for maintaining a sulfur concentration in synthesis gas, the method comprising: adding sulfur to the carbonaceous material to produce a sulfur-comprising carbonaceous feedstock comprising at least 0.05 vol% sulfur; Introducing a sulfur-containing carbonaceous feedstock to a transport gasifier to generate syngas; detection of sulfur concentrations in syngas; and The amount of sulfur added to the carbonaceous material is adjusted based on the detected sulfur concentration to maintain the sulfur concentration in the syngas at about 0.1 vol% or higher. 13. The method of claim 12, further comprising increasing the amount of sulfur added to the carbonaceous material when the sulfur concentration in the syngas is below 0.1 vol%. 14. The method of claim 12, further comprising reducing the amount of sulfur added to the carbonaceous material when the sulfur concentration in the syngas is above about 0.4 vol%. 15. A method for maintaining sulfur concentration in syngas, said method comprising: adding sulfur to the carbonaceous material at a controlled rate to generate a carbonaceous mixture comprising sulfur, wherein the first feeder adjusts the controlled rate of sulfur; introducing a sulfur-containing carbonaceous mixture into the feed system to produce a sulfur-containing carbonaceous feed; introducing a carbonaceous feedstock comprising sulfur into a gasifier operating under conditions sufficient to generate synthesis gas; Detection of sulfur concentration in syngas; adjusting the first feeder to increase the rate at which sulfur is added to the carbonaceous material when the sulfur concentration is below 0.1 vol%; and When the sulfur concentration is above 0.4 vol%, the first feeder is adjusted to reduce the rate of sulfur addition to the carbonaceous material. 16. The method of claim 15, further comprising changing the pressure of the sulfur-containing carbonaceous material from atmospheric pressure to a gasifier operating pressure. 17. The method of claim 15, wherein the gasifier operates at a temperature of about 700°C to about 1,000°C. 18. The method of claim 15, further comprising introducing the syngas into one or more coolers to generate cooled syngas, wherein after the syngas is cooled, detecting sulfur in the syngas concentration. 19. The method of claim 18, further comprising: introducing the cooled syngas to a particulate control device to partially or completely remove particulates from the cooled syngas to produce particulate-depleted syngas and separated particulates; detecting the concentration of sulfur in the particulate-lean syngas using a second analyzer; adjusting the metering feeder to increase the rate at which sulfur is added to the carbonaceous material when the sulfur concentration of the particulate-lean syngas is below a first threshold; and The metering feeder is adjusted to reduce a rate of sulfur addition to the carbonaceous material when the sulfur concentration of the particulate-lean syngas is above a second threshold. 20. The method of claim 15, wherein the gasifier operates at a pressure of about 750 kPa to about 2,500 kPa.

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