propane deasphalting unit: Topics by afrocolombianidad.info
Subsurface upgrading via solvent deasphalting is an innovative concept that has . Bahram Mokhtari, N., "The VAPEX process, from beginning up to date". Process Simulation of Solvent Deasphalting Plants With PROII - Free download as PDF File .pdf), Text File .txt) or view presentation slides online. An enhanced solvent deasphalting process is used to treat the feedstock to Omer Refa Koseoglu; Original Assignee: Saudi Arabian Oil Company; Priority date .. The use of computer modeling is described by J. F. Schabron and J. G.
For example, solvent deasphalting typically involves physically separating the lighter hydrocarbons and the heavier hydrocarbons including asphaltenes based on their relative affinities for the solvent. A light solvent such as a C3 to C7 hydrocarbon can be used to dissolve or suspend the lighter hydrocarbons, commonly referred to as deasphalted oil, allowing the asphaltenes to be precipitated.
The two phases are then separated and the solvent is recovered. Additional information on solvent deasphalting conditions, solvents and operations may be obtained from U. Several methods for integrating solvent deasphalting with hydrocracking in order to remove asphaltenes from resid are available. One such process is disclosed in U.
These patents disclose contacting the residue feed in a solvent deasphalting system to separate the asphaltenes from deasphalted oil. The deasphalted oil and the asphaltenes are then each reacted in separate hydrocracking reactor systems.
For example, operating the asphaltenes hydrocracker at high severity in order to increase the conversion may also cause a high rate of sediment formation, and a high rate of catalyst replacement. In contrast, operating the asphaltenes hydrocracker at low severity will suppress sediment formation, but the per-pass conversion of asphaltenes will be low.
In order to achieve a higher overall resid conversion, such processes typically require a high recycle rate of the unreacted resid back to one or more of the hydrocracking reactors. The process may include: In another aspect, embodiments disclosed herein relate to a process for upgrading resid. Other aspects and advantages will be apparent from the following description and the appended claims. Residuum hydrocarbon resid feedstocks useful in embodiments disclosed herein may include various heavy crude and refinery fractions.
The above resid feedstocks may include various impurities, including asphaltenes, metals, organic sulfur, organic nitrogen, and Conradson carbon residue CCR. Processes according to embodiments disclosed herein for conversion of resid hydrocarbon feedstocks to lighter hydrocarbons include initially hydrocracking the resid feedstock, including any asphaltenes contained therein.
The entire resid feed, including asphaltenes, may be reacted with hydrogen over a hydrocracking catalyst in a first hydrocracking reaction stage to convert at least a portion of the hydrocarbons to lighter molecules, including the conversion of at least a portion of the asphaltenes.
In order to mitigate sediment formation, the first stage hydrocracking reaction may be conducted at temperatures and pressures that may avoid high rates of sediment formation and catalyst fouling i. The reaction product from the first stage may then be separated to recover at least one distillate hydrocarbon fraction and a resid fraction including unreacted resid feed, asphaltenes, and any resid-boiling range products resulting from hydrocracking of the asphaltenes contained in the resid feedstock.
The resid fraction may then be separated in a solvent deasphalting unit to recover a deasphalted oil fraction and an asphaltenes fraction. The solvent deasphalting unit may be, for example, as described in one or more of U.
In the solvent deasphalting unit, a light hydrocarbon solvent may be used to selectively dissolve desired components of the resid fraction and reject the asphaltenes. In some embodiments, the light hydrocarbon solvent may be a C3 to C7 hydrocarbon, and may include propane, butane, isobutane, pentane, isopentane, hexane, heptane, and mixtures thereof. The deasphalted oil fraction may be reacted with hydrogen over a hydrocracking catalyst in a second hydrocracking reaction stage to convert at least a portion of the hydrocarbons to lighter molecules.
The reaction product from the second hydrocracking reaction stage may then be separated along with the reaction product from the first hydrocracking stage to recover distillate range hydrocarbons produced in both the first and second hydrocracking reaction stages.
Processes according to embodiments disclosed herein thus include a solvent deasphalting unit downstream of the first hydrocracking reaction stage, providing for conversion of at least a portion of the asphaltenes to lighter, more valuable hydrocarbons.
Journal of Nanomaterials
Additionally, due to conversion of at least a portion of the asphaltenes upstream, the required size for solvent deasphalting units used in embodiments may be less than would be required where the entire resid feed is initially processed.
Catalysts used in the first and second reaction stages may be the same or different. Suitable hydrotreating and hydrocracking catalysts useful in the first and second reaction stages may include one or more elements selected from Groups of the Periodic Table of the Elements.
In some embodiments, the hydrotreating and hydrocracking catalysts according to embodiments disclosed herein may comprise, consist of, or consist essentially of one or more of nickel, cobalt, tungsten, molybdenum and combinations thereof, either unsupported or supported on a porous substrate such as silica, alumina, titania, or combinations thereof.
As supplied from a manufacturer or as resulting from a regeneration process, the hydroconversion catalysts may be in the form of metal oxides, for example. If necessary or desired, the metal oxides may be converted to metal sulfides prior to or during use.
Reactors suitable for use in the first hydrotreating and hydrocracking reaction stage may include any type of hydrocracking reactor. Ebullated bed reactors and fluidized bed reactors are preferred due to the processing of asphaltenes in the first reaction stage. In some embodiments, the first hydrocracking reaction stage includes only a single ebullated bed reactor. Failure to do so interferes with subsequent refining operations. In these tests, the residue remaining after a specified period of evaporation and pyrolysis is expressed as a percentage of the original sample.
For example, deasphalted oil obtained from vacuum residue of an Arabian crude oil contains 4. In another example, a deasphalted oil of Far East origin contains 0. These high levels of contaminants, and particularly nitrogen, in the deasphalted oil limit conversion in hydrocracking or FCC units. The adverse effects of nitrogen and micro-carbon residue in FCC operations have been reported to be as follows: See Sok Yui et al. Similarly, coke yield is 0. In hydrocracking operations, the catalyst deactivation is a function of the feedstock nitrogen and MCR content.
Organic nitrogen compounds poison the active catalytic sites resulting in catalyst deactivation, which in turn reduces catalyst cycle process length, catalyst lifetime, product yields, and product quality, and also increases the severity of operating conditions and the associated cost of plant construction and operations.
Coke is generally treated as a low value by-product. It is removed from the units and can be recovered for various uses depending on its quality. Traditional coking processes using these feeds produce coke which has substantial sulfur and metal content. The goal of minimizing air pollution is a further incentive for treating residuum in a coking unit since the gases and liquids produced contain sulfur in a form that can be relatively easily removed.
USB2 - Asphalt production from solvent deasphalting bottoms - Google Patents
An enhanced solvent deasphalting process is used to treat the feedstock to reduce the level of asphaltenes, N, S and metal contaminants and produce a deasphalted oil with reduced contaminants. A coking process is integrated so that the deasphalted oil with reduced contaminants is the coking unit feedstock, facilitating production coker liquid and gas fractions and recovery of petroleum green coke.
Enhanced solvent deasphalting processes, such as those described in commonly owned US Patent Numberwhich is incorporated by reference herein in its entirety, are used to process the heavy crude oils or fractions.Why You Shouldn't Play Dating Simulators
The deasphalted oil is thermally cracked in a coking unit, such as a delayed coking unit. In contrast to typical coking operations in which the coke is low market value by-product, in the integrated process herein, using as an initial feed heavy crude oils or fractions having reduced asphaltenes, metal and sulfur content, petroleum green coke recovered from the coker unit drums is low in sulfur and metals. In contrast to typical coking operations in which the coke is low market value by-product, in the integrated process herein, high quality petroleum green coke recovered from the coker unit drums is low in sulfur and metals.
Table 1 shows the properties of these types of coke. Calcination occurs by thermal treatment to remove moisture and reduce the volatile combustible matter. Contaminants are adsorbed and the solvent and deasphalted oil fraction is removed as a separate stream from which the solvent is recovered for recycling.
The solvent-asphalt mixture is sent to a fractionator for recovery and recycling of the aromatic or polar solvent. Bottoms from the fractionator include the desorbed contaminants are further processed as appropriate. The deasphalted oil having reduced contaminants is thermally cracked in a coking unit, such as a delayed coking unit, and coker liquid and gas products are recovered, along with high quality petroleum green coke.
An effective quantity of solid adsorbent material mixed with the primary deasphalted oil phase, which contains the deasphalted oil and paraffinic solvent.
The paraffinic solvent is separated from the deasphalted oil and adsorbent material, and the solvent is recovered for recycling. The material is provided in particulate form of suitable dimension, such as granules, extrudates, tablets, spheres, or pellets of a size in the range of mesh.
The quantity of the solid adsorbent material used in the embodiments herein is about 0. Advantageously, the integrated processes herein facilitate recovery of such high quality petroleum green coke since the feed to the delayed coking unit has desirable qualities. In particular, the deasphalted oil stream in the present process is characterized by a sulfur content of generally less than about 3. Conventionally, coking of residuum from heavy high sulfur, or sour, crude oils is carried out primarily as a means of utilizing such low value hydrocarbon streams by converting part of the material to more valuable liquid and gas products.
Typical coking processes include delayed coking and fluid coking. The hot mixed fresh and recycle feedstream is maintained in the coke drum at coking conditions of temperature and pressure where the feed decomposes or cracks to form coke and volatile components. One or more heavy fractions of the coke drum vapors can be condensed, for instance quenching or heat exchange. In certain embodiments the contact the coke drum vapors are contacted with heavy gas oil in the coking unit product fractionator, and heavy fractions form all or part of a recycle oil stream having condensed coking unit product vapors and heavy gas oil.
In certain embodiments, heavy gas oil from the coking feed fractionator is added to the flash zone of the fractionator to condense the heaviest components from the coking unit product vapors. When the coke drum is full of coke, the feed is switched to another drum, and the full drum is cooled.
Liquid and gas streams from the coke drum are passed to a coking product fractionator for recovery. Any hydrocarbon vapors remaining in the coke drum are removed by steam injection. In the delayed coking production of high quality petroleum green coke, unconverted pitch and volatile combustible matter content of the green coke intermediate product subjected to calcination should be no more than about 15 percent by weight, and preferably in the range of 6 to 12 percent by weight.
The catalyst can promote cracking of the heavy hydrocarbon compounds and promote formation of the more valuable liquids that can be subjected to hydrotreating processes downstream to form transportation fuels.
The catalyst and any additive s remain in the coking unit drum with the coke if they are solids, or are present on a solid carrier. Two main types of asphaltic concrete compositions include hot-mix and cold-mix.
Cold-mix asphalt generally incorporates emulsified or cut-back asphalts, and is usually used for light to medium traffic secondary roads, in remote locations or for maintenance use. Hot-mix asphalt is commonly used for heavier traffic, and is a mixture of suitable aggregate coated with asphalt. Asphalt and aggregate are combined in a mixing facility where they are heated, proportioned, and mixed to produce the desired paving mixture. Batch-type hot-mixing facilities use different size fractions of hot aggregate which are drawn in proportional amounts from storage bins to make up a single batch for mixing.
The combination of aggregates is dumped into a mixing vessel. A proportional amount of asphalt is thoroughly mixed with the aggregate in the mixing vessel. After mixing, the material is then emptied into trucks, storage silos, or surge bins. The drum-mixing process heats and blends the aggregate with asphalt all at the same time in the drum mixer. When the mixing is complete, the hot-mix is then transported to the paving site and spread in a partially compacted layer to a uniform, even surface with a paving machine.
While still hot, the paving mixture is further compacted by heavy rolling machines to produce a smooth pavement surface. The quality of asphalt is affected by the inherent properties of the petroleum crude oil from which it was produced. Different oil fields and geographic regions produce crude oils with very different characteristics. The refining method also impacts the asphalt quality. For engineering and construction purposes, important factors include: The consistency or viscosity of asphalt varies with temperature, and asphalt is graded based on ranges of consistency at a standard temperature.
Careless temperature and mixing control can cause more hardening damage to asphalt than many years of service on a roadway. A standardized viscosity or penetration test is commonly specified to measure paving asphalt consistency.
Air-blown asphalts typically use a softening point test. Purity of asphalt can be easily tested since it is composed almost entirely of bitumen, which is soluble in carbon disulfide. Refined asphalts are usually more than Because of the hazardous flammable nature of carbon disulfide, trichloroethylene TCEwhich is also an excellent solvent for asphalt, is used in the solubility purity tests.
Asphalt must be free of water or moisture as it leaves the refinery. However, transports loading the asphalt may have moisture present in their tanks or beds. If heated to a sufficiently high temperature, asphalt will release fumes which can flash in the presence of a spark or open flame.
The temperature at which this occurs, the flashpoint, is well above temperatures normally used in paving operations. Because of the possibility of asphalt foaming and to ensure an adequate margin of safety, the flashpoint of the asphalt is measured and controlled.
Another important engineering property of asphalt is its ductility, which is a measure of a material's ability to be pulled, drawn, or deformed. The presence or absence of ductility is usually more important than the actual degree of ductility because some asphalt compositions having a high degree of ductility are also more temperature sensitive. The elongation at which the asphalt sample breaks is a measure of the ductility of the sample. The solid adsorbent material can include attapulgus clay, alumina, silica activated carbon and zeolite catalyst materials, and combinations of those adsorbent materials.
The solid asphaltenes formed in the paraffinic solvent phase are mixed with the adsorbent material for a time sufficient to adsorb sulfur- and nitrogen-containing polynuclear aromatic molecules on the adsorbent material. The aromatic or polar solvent mixture is then passed to a fractionator to recover the solvent.
Adsorbent materials such as attapulgus clay, alumina, silica, activated carbon, silica alumina or zeolite catalyst material are used in the enhanced solvent deasphalting process described in U. Disposal of these adsorbent as waste materials incurs substantial expense and entails environmental considerations. In addition, when adsorbent materials are reconditioned, for example, by solvent desorption, heat desorption or pyrolysis at high temperatures, the process reject removed from the adsorbent materials must also be disposed of.
Therefore, a need exists for a cost-effective solution for eliminating refinery process waste, including spent catalytic and non-catalytic adsorbent materials, as well as adsorbate process reject materials derived from desorption, while minimizing conventional waste handling demands. According to the present invention, an asphalt composition is provided comprising asphalt and spent adsorbent material from a solvent deasphalting unit.
The asphalt can comprise asphaltic material obtained from a solvent deasphalting unit, and spent adsorbent material in the asphalt composition that was previously utilized in the solvent deasphalting unit. The asphalt composition can include spent adsorbent material selected from the group consisting of attapulgus clay, alumina, silica, activated carbon, silica alumina and zeolite catalyst material derived from one or more intermediate refining processes of hydrotreating, hydrocracking, or fluid catalytic cracking, and combinations comprising at least one of the foregoing adsorbent materials.
As stated above, petroleum asphalt is the heavy residue of the oil refining process, or bottoms, from distillation units or other intermediate refining process units such including hydroprocessing, visbreaking, coking and solvent deasphalting.
Asphalt from various sources is typically integrated into petroleum asphalt pools for collection and storage until asphalt product is ready to transport. According to the present invention, a solvent deasphalting process encompassing the recycle of waste materials includes: The solid adsorbent material is selected from the group consisting of attapulgus clay, alumina, silica activated carbon, zeolite catalyst materials and mixtures thereof.
According to another aspect of the present invention, a solvent deasphalting process encompassing the recycle of waste materials includes: In yet another embodiment, the process further comprises h. The present invention utilizes the waste solid adsorbent materials and liquid process reject stream containing heavy polynuclear aromatics from an enhanced solvent deasphalting unit by passing the solid-containing asphalt mixtures into the asphalt blending pool. If the asphalt-containing waste solid material is not sent to the asphalt pool, other disposal options must be found for the solid adsorbent materials.
The process waste, whether it is adsorption process liquid water or solid waste, can be utilized in asphalt blends. The present invention, therefore, solves the problem of disposing of wastes from solvent deasphalting processes utilizing adsorption and other processes using solid adsorbent materials in a petroleum refinery.
In general, the asphalt composition includes solids in a range of about 0. In one embodiment, the asphalt composition can include petroleum asphalt derived from a solvent deasphalting process, where a solute material including asphaltenes is separated from a hydrocarbon oil feedstock containing asphaltenes with a paraffinic solvent.
Paraffinic solvents used in solvent deasphalting generally having from 3 to 8 carbons, as is conventionally known.