Main equipment of Shell gasifier

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I. Introduction to the equipment structure: The key equipment for gasification consists of a gasification furnace, gas transfer pipes, and a syngas cooler. The overall structure consists of an outer shell and inner components. The shell withstands static pressure, while the internal components form a gasification space, a slag collection space, gas delivery channels, and protective shields; the necessary heat transfer surfaces are arranged within the cylindrical protective shields in the syngas cooler section. Within the gasifier, there are a gasification chamber, a slag pool, and a quenching section ； The syngas cooler is equipped with 2 stages of evaporators. To effectively control the coal powder gasification and gas cooling processes as well as to provide proper protection for the equipment’s pressure shell, the basic design for the internal components is a membrane-type water wall structure. The diameter and length of the gasifier, gas pipeline, and syngas cooler housings are determined by the requirements for the gasification space, the dimensions of the components inside the gas pipelines, the heat transfer area of the syngas cooler, as well as the needs related to the arrangement, installation, and maintenance of these components. An annular space of 750 mm is left between the internal components and the pressure shell to facilitate the entry and exit of air and water pipelines, the installation of distributors and air collection boxes, the assembly and welding of the internal components, non-destructive testing, and regular maintenance of these components. The syngas cooler is supported in a floating manner using reliable constant-force hangers to meet the requirements of thermal expansion of the equipment. II. Description of the main process: Partial oxidation at (1400–1600°C) is used to produce syngas and ash. The syngas emerges from the top of the reaction chamber; it is then cooled to around 900°C by syngas from subsequent processes. Further cooling takes place through gas pipelines, a gas return chamber, and the membrane-type water-cooling walls in the syngas cooler, bringing the temperature down to around 330°C. This results in a process gas – syngas – with a high effective gas content (CO + H2), suitable for ammonia production. Most of the slag flows from the conical bottom of the reaction chamber in a molten state into the slag pool, where it is **quenched to form uniform glass-like particles, which are then removed from the area by a slag breaker using a hopper system. III. Introduction to Pressure Vessels The key equipment for gasification, namely pressure vessels, are usually divided into four parts: the gasification furnace, the dome/gas transfer pipe, the gas return chamber, and the syngas cooler. The normal temperature at the outlet end of the syngas cooler shell is 330°C, with a maximum temperature of 360°C. Furnace shell: diameter 3680; quenching tube casing: diameter 2500; gas pipeline casing: diameter 2500; syngas cooler casing: diameter 2900. Support system: The key equipment for gasification is supported in two places, one of which is fixed to the concrete floor structure via skirt-type supports at the bottom of the gasification furnace ； The other is suspended from a specially designed steel beam through a floating support system composed of a constant-force hoist and a skirt-type support located at the bottom of the syngas cooler. IV. Introduction to the Equipment’s Internal Components 4.1 Vaporization Section 4.1.1 Cylindrical water-cooled membrane wall heat transfer surface in the vaporization section: 1 set of cylindrical heat exchangers, with a tube-fin-tube structure; the material used is 1.7335 ； It includes the following tubular accessories: 1 manhole with a cooling insert, 4 burner covers, 2 flame monitors, 1 start-up burner, 1 igniter; 1 set of primary annular distributors, 1 set of secondary annular distributors, 1 set of annular steam collectors, La Mont throttle nozzles. The membrane-type wall heat transfer surface is equipped with 2,500 pins per m2. 4.1.2. 1 bottom for the gasifier with a slag outlet cone; 1 spiral-wound heat transfer surface composed of double-Ω tubes, made of material 1.7335. Steam collectors/distributors, La Mont nozzles, pins for the gasifier bottom – approximately 2,200 per m2. The surfacing material for the slag outlet is NiCr 625 IG. 4.1.3. 1 top for the gasifier/cone-shaped bottom for quenching; 1 spiral-wound heat transfer surface made of straight tubes, with the edges of the tubes in contact with the feed gas being surfaced; the surfacing material is NiCr625IG. 4 distributors, 4 steam collectors, 1 annular steam collector, La Mont nozzles, pins for the gasifier top – approximately 2,200 per m2, material SS310 (1.4841). 4.2 Slag tank. 4.2.1. 1 cone-shaped slag tank with a membrane-type water-cooling wall; 1 spiral-wound heat transfer surface made of straight tubes welded together with round steel. Distributors, steam collectors, La Mont nozzles, pins for the cone-shaped slag tank wall – 2,200 per m2. 4.2.2. 1 cylindrical slag tank/thermal skirt with a membrane-type water-cooling wall; 1 spiral-wound heat transfer surface made of super-Ω tubes, 2 distributors, 2 steam collectors, La Mont nozzles. 4.2.4. 1 slag tank ring (12″ sch.60); 4 water supply pipes between the ring and the pressure vessel (6″ sch.80). 4.2.3. 1 slag tank cone and cylinder; 1 metal shield. 4.3 Normal quencher: Channels with guide vanes (distribution plates), connection pipes between the channels and the pressure vessel, expansion joints for each connection pipe. 4.3.1. 1 quenching tube; 1 cylindrical heat transfer surface consisting of tubes-fin-tubes, with a forged ring at the bottom; 1 pressure difference measurement port K1. Forged impact anvils and forged supports that form an integral part with the heat exchanger; 1 annular distributor, 1 annular steam collector, connection pipes between the distributors/steam collectors and the heat transfer surface, La Mont nozzles, connection pipes between the distributors/steam collectors and the pressure vessel connections. Fixing devices. 1.1.7. 4 burner covers, each consisting of the following components: 1 spiral-wound cone-shaped heat transfer surface, sealed and welded using round steel; 1 tubular distributor/steam collector, connection pipes between the distributor/steam collector and the heat transfer surface, La Mont nozzles, connection pipes between the distributor/steam collector and the pressure vessel connections. Flange covers. 1.1.8. 1 manhole cooler, consisting of a flat coil component made of straight tubes, approximately 500×500 mm in size, made of material 1.7335. Connection pipes between the heat transfer surface and the pressure vessel, including flange fittings, made of material 1.7335. La Mont nozzles, made of material 1.7335/X20Cr13. Flange covers, made of material 1.5415. 1.1.9.3. 1 set of seals between the lower part of the gasifier’s membrane-type water-cooling wall and the pressure vessel, made of material 2.4858 (IN825)/1.7335. 1.1.9.4. 1 ventilation ring consisting of 4 sections, made of material 1.7335. Connection pipes between the ventilation ring and the pressure vessel, made of material 1.7335. Fixing devices. 1.1.10. Normal quencher: Channels with guide vanes (distribution plates), made of material 2.4858 (IN825). Connection pipes between the channels and the pressure vessel, made of material 2.4858 (IN825). Expansion joints for each connection pipe, made of material 2.4858 (IN825). Support fixing devices. 1.1.11. High-speed quencher: Backflow device at the inlet of the quenching tube; 1 annular distributor, made of material 2.4858 (IN825). Nozzle tubes, made of material 2.4858 (IN825). Connection pipes between the high-speed quenching tube and the pressure vessel connections, made of material 2.4858 (IN825). Support fixing devices