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A new domestic catalytic cracking process with a high yield of light olefins which corresponds to the best foreign analogs with respect to the technical and economic indexes is described. This process differs from the traditional process by more severe conditions of cracking the feedstock, an increased content of ZSM-5 additive in the equilibrium catalyst, and conducting repeated cracking of light naphtha in an additional continuous reactor.In developing and implementing technology for catalytic cracking with a high yield of light olefins, the results of experimental studies on a micropilot unit [1], experience in designing modern catalytic cracking systems with traditional technology [2,3], and revamping of nine active units of different types (G-43-107, KT-1, 1A/1M, GK-3, etc.) were used. The distinctive features of the process are conducting it at high temperatures and catalyst recycle ratios, the high content of zeolite ZSM-5 catalytic additive in the equilibrium catalyst, and repeated cracking of light naphtha in an additional continuous reactor in more severe conditions than in cracking of fresh feedstock.The new process provides for the following basic reactor block technological and implementation units, most of which have worked reliably in industrial cat crackers:• basic continuous reactor, including a regenerated acceleration section, a feedstock input unit with high-efficiency spray nozzles [8] and an upward-flow feedstock-catalyst contact section;• an additional continuous reactor for cracking recycling light naphtha in an ascending stream of regenerated catalyst in severe conditions that split low-molecular-weight hydrocarbons;• centrifugal-inertial separators [9] at the end of the basic and supplementary continuous reactors that ensure fast separation of feedstock and light naphtha cracking products from the used catalyst;• high-efficiency one-stage reactor cyclones directly connected to the centrifugal-inertial separators;

mentioning

confidence: 99%

“…In developing and implementing technology for catalytic cracking with a high yield of light olefins, the results of experimental studies on a micropilot unit [1], experience in designing modern catalytic cracking systems with traditional technology [2,3], and revamping of nine active units of different types (G-43-107, KT-1, 1A/1M, GK-3, etc.) were used.…”

mentioning

confidence: 99%

Development of a catalytic cracking process with a high yield of light olefins: technology and implementation

Solyar

Glazov

Klimtseva

et al. 2010

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“…From 1997 through 2004, studies were conducted to improve the process and equipment in the reactor unit of the CC, which had included the installation of highly effective feedstock and slime injectors in the straight-run reactor, modernization of the stripping section of the reactor with the assembly of cascading trays and refined vapor-distributing devices, and the installation of tubular air distributors and highly effective regenerator cyclones [2,3].…”

mentioning

confidence: 99%

Rebuilding of the reactor in a G-43-107M/1 cat cracker

Solyar

Glazov

Liberzon

et al. 2009

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The rebuilding of the reactor for a cat cracker with incorporation of a set of new process components and equipment subassemblies, which are directed toward a reduction in the portion of nonselective secondary reactions taking place in the separation and stripping sections of the reactor, is described; this has made it possible to improve the productivity and effectiveness of the cat cracker.A combined G-43-107M/1 cat cracker has been in service at the Ufa Oil Refinery since 1955. During its construction, the reactor of the cat cracker (CC) was rebuilt on the basis of technology provided by one of the foreign companies [1].From 1997 through 2004, studies were conducted to improve the process and equipment in the reactor unit of the CC, which had included the installation of highly effective feedstock and slime injectors in the straight-run reactor, modernization of the stripping section of the reactor with the assembly of cascading trays and refined vapor-distributing devices, and the installation of tubular air distributors and highly effective regenerator cyclones [2, 3].Since 2004, the cat cracker has been operating on four-year inter-overhaul cycles, the first of which was successfully completed in 2008. Equipment inspection of the reactor unit of the CC after such an extended run indicated that it is in good condition, and does not require any significant repair or restorative work.The vacuum gasoil of a mixture of Western Siberian and Bashkir crudes (the content of the latter attains 45 wt. %) with an end boiling point of 560-570°C is refined in the combined cat cracker. Up to 15 wt. % of heavy viscosity-breaking gasoil is drawn into the CC. After hydrofinishing under comparatively mild conditions, the density of the feedstock ranges from 908 to 912 kg/m 3 , and the carbon residue (Conradson carbon) from 0.3 to 0.5 wt. %.The characterization factor of the hydrofinished feedstock does not exceed 11.7; this permits it to be classified as highly aromatized, and difficult-to-crack. In refining such a feedstock prior to rebuilding of the reactor, the regeneration temperature was close to the limiting allowable value of 730°C.

“…1) is a compact two-stage system designed for rapid extinction of catalytic reactions where the gas-catalyst stream comes out of the RR. It was developed with the results of experiments on a large-scale gas-dynamics bench and is protected by a RF patent [2,3]. Due to the insufficient number of cascade devices in the stripping section, the efficiency of stripping the catalyst was low.…”

mentioning

confidence: 99%

Revamping of the catalytic cracking reactor block on the G-43-107M/1 unit. Second stage

Solyar¹,

Glazov²,

Liberzon³

et al. 2005

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Revamping of the catalytic cracking reactor block on the combined G-43-107M/1 unit with introduction of a set of new technological elements and equipment units that significantly increase the efficiency andreliability of operation of the unit and create conditions for its conversion to two-year operation between maintenances is described. Key words: catalytic cracking, reactor block equipment, reactor, regenerator, cyclones, separation unit, reactor stripping section, unit for periodic unloading of spent catalyst, efficiency of dust removal, naphtha cut, octane number. The cat cracker (CC) block (CB) on the combined G-43-107M/1 unit was revamped at LINOS Ltd. (Lisichansk, Ukraine) in two stages, in periods of scheduled major maintenance -in 2002 and 2003-2004. The first stage is described in [1].The second stage of revamping included: assembly of high-efficiency cyclones in the reactor and regenerator and separation unit at the end of the riser reactor (RR); modernization of the reactor stripping section with installation of improved cascade trays and steam-distribution equipment; replacement of the internal section of the RR; installation of a system for periodic unloading of spent catalyst.In constructing this unit, the CC was revamped with French Petroleum Institute technology. In particular, the stage II cyclones were taken down and the stage I cyclones were kept (i.e., a one-stage cyclone system for dust removal was created) and a ballistic separator was installed at the end of the RR.Each cyclone was welded to the gas-collecting chamber by an outlet pipe on the cover of the unit with two vertical rods. The design of the rods did not ensure that they could freely rotate in the direction of horizontal movement of the rod attachments on the cover of the cyclone in heating, so that additional thermal loads arose.The cyclones were distinguished by a low height-to-diameter ratio of the cylindrical part of the body (~4.3), which restricted the efficiency of dust removal.The dust-return risers on the cyclones were equipped with a check valve equipped with a horizontal cut-off plate with a counterweight. The valve design wedged the plate in rotation around the axis of the hinge and