Study of the Effect of Attrition on the Properties of Catalyst Used for Industrial FCC Operation (original) (raw)
Related papers
Prediction of the Catalyst Attrition Rate in an Industrial Fluid Catalytic Cracking Operation
World journal of innovative research, 2019
Attrition occurs due to particle motion and inter-particle collision and therefore is a major source of catalyst deactivation in fluid catalytic cracking (FCC) processes which results in loss of valuable catalyst materials, reduced process efficiency, and equally affects production. This work aims at predicting the attrition rate of a commercial catalyst used for industrial FCC operation. Design and operation data were used to carry out technical evaluation, physicochemical property test analysis, and modeling. Results show that mechanical stress rather than the thermal stress gave rise to attrition in this unit. The specific attrition rate which was modeled with the exponential decay model had R 2 value of 0.999, Standard Error of 0.000908 and RSS value of and therefore adequately modeled this rate. It was assumed that abrasion was solely responsible for attrition in this unit and that attrited particles were lost as microfines and not retained within the unit during operation.
Catalyst deactivation and the effect of catalyst makeup on the FCC unit
Global Journal of Engineering and Technology Advances, 2023
One of the significant processes of the crude oil refining process is the fluid catalytic cracking (FCC) unit. This unit produces olefins and other feedstock for the petrochemical industry as well as high octane gasoline, naphtha, light cycle oil, and heavy cycle oil. Attrition is one of the forms of catalyst deactivation on FCC catalyst which affects its operation, thereby giving rise to a high amount of catalyst makeup to compensate for the losses in this unit. This study investigated the effect of catalyst attrition on a commercial FCC unit through an analysis of its technical data from 4-run operations. The catalyst loss profile was evaluated while the scanning electron microscopy (SEM) showed abrasion as the dominant attrition type in the unit, hence resulting in many catalyst particles being lost as micro fines through elutriation. A simulation study was carried out using ASPEN HYSYS version 8.8 to assess the effects of reduction and increment of fresh catalyst makeup on the product yield while a cost analysis was done to evaluate the economic implication. The results showed that a 2% reduction of the current daily catalyst makeup gave the same yield as that of the reference value. The products also had similar qualities showing that $117,000.00/annum could be saved by a 2% reduction of the current catalyst makeup.
Attrition due to mixing of hot and cold FCC catalyst particles
Powder Technology, 2003
The formation of fines in a fluidized catalytic cracker unit (FCCU) due to catalyst attrition and fracture is a major source of catalyst loss. In addition to the generation of fine particles, a significant amount of aerosols have been identified in the stack emission of FCCUs. To determine the source of these aerosols, samples of fresh and equilibrium (e-cat) type catalysts were heated up to 600 jC and mixed with cold samples, simulating the thermal shock and particle fracture, which occurs inside an FCCU when catalyst is added. The thermal shock in the experiments produced fine particles and aerosols, which were captured on filters and analyzed using scanning electron microscopy (SEM) imaging and atomic absorption tests. It was found that significant quantities of metal rich aerosols were generated by the thermal shock. This production of fine particles and aerosols is a new phenomenon that can help explain excessive catalyst emissions from operating FCCUs. D
MDPI, 2023
In the FCC conversion of heavy petroleum fractions as atmospheric residues, the main challenge for refiners to achieve the quantity and quality of various commercial products depends essentially on the catalyst used in the process. A deep characterization of the catalyst at different steps of the process (fresh, regenerated, and spent catalyst) was investigated to study the catalyst’s behavior including the physicochemical evolution, the deactivation factor, and kinetic–thermodynamic parameters. All samples were characterized using various spectroscopy methods such as N2 adsorption–desorption, UV-visible spectroscopy, Raman spectroscopy, LECO carbon analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF), nuclear magnetic resonance spectroscopy (NMR13C) analysis, and thermogravimetric analysis. The results of the N2 adsorption–desorption, UV-vis, Raman, LECO carbon, and SEM imaging showed that the main causes of catalyst deactivation and coking were the deposition of carbon species that covered the active sites and clogged the pores, and the attrition factor due to thermal conditions and poisonous metals. The XRD and XRF results showed the catalyst’s physicochemical evolution during the process and the different interlinks between catalyst and feedstock (Nickel, Vanadium, Sulfur, and Iron) elements which should be responsible for the coking and catalyst attrition factor. It has been found that, in addition to the temperature, the residence time of the catalyst in the process also influences catalyst structure transformation. NMR13C analysis revealed that polyaromatic hydrocarbon is the main component in the deposited coke of the spent catalyst. The pyridine-FTIR indicates that the catalyst thermal treatment has an influence on its Brønsted and Lewis acid sites and the distribution of the products. Thermogravimetric analysis showed that the order of catalyst mass loss was fresh > regenerated > spent catalyst due to the progressive losses of the hydroxyl bonds (OH) and the structure change along the catalyst thermal treatment. Moreover, the kinetic and thermodynamic parameters showed that all zones are non-spontaneous endothermic reactions. Keywords: fluidized catalytic cracking; catalyst characterization; catalyst deactivation; coking mechanism; mass loss; catalyst kinetic; thermodynamic parameters
FCC catalyst attrition behavior at high temperatures
2020
In this work, High temperature attrition was studied in a standard attrition set up to mimic the FCC regenerator environment along with mechanical attrition. Operating conditions were modified in this pilot due to application of high temperatures. Two parameters i.e. time and temperature in the ranges of 1 to 5hr and 673-973K were surveyed respectively. The behavior of attrition and mass loss was modeled and validated. At higher temperatures; mass loss response sensitivity became larger. Finally, PSD and SEM tests were used to investigate the attrition mechanism. In the ambient tests, abrasion was significant while at higher temperatures, fragmentation was considerable. PSD plots shifted into larger particles and the SEM images showed those changes as well. In addition, significant reshaping in the PSD curves indicated particles cracking at high temperatures.
Industrial & Engineering Chemistry Research, 2001
Spray drying has been recently used by this research team in the preparation of Fe Fischer-Tropsch catalysts with higher attrition resistance for use in slurry bubble column reactors. In the first paper in this series, the effects of the type, concentration, and network structure of SiO 2 on the attrition resistance of two series of spray-dried Fe catalysts in their calcined state were explored and the dependence of catalyst attrition resistance on catalyst particle density was discussed. As a continuation of our previous effort, the effect of carburization on catalyst attrition resistance was studied and is presented in this paper. After carburization, the majority component of the catalysts, hematite (Fe 2 O 3 ), was converted to iron carbides, mostly -carbide (Fe 2 C 5 ). Breakage of individual catalyst particles and fines formation, which can be considered as evidence of chemical attrition, was only observed during carburization of the catalyst with low SiO 2 concentration <9 wt %. With an increase in the total concentration of SiO 2 , such chemical attrition during the Fe phase change appeared to be eliminated or negligible except for the breakup of large agglomerates during carburization. There were, generally, significant decreases in the Brunauer-Emmett-Teller surface areas and average particle sizes of the catalysts upon carburization. Surprisingly, carburization of these Fe catalysts did not weaken the particle structures with regards to physical attrition. In fact, depending on catalyst composition, the overall attrition resistances of the carburized catalysts measured using a jet cup system were similar to or better than those of the same catalysts in their calcined form. However, any seeming improvement in attrition resistance is suggested to be related mainly to the increase in catalyst particle density (related to catalyst inner structure) after carburization.
Analysis of the Utilization of Waste Catalysts from Catalytic Cracking Reactors in Oil Industry
Environmental Engineering and Management Journal
This article covers the investigation of the catalyst waste (T.R.M 1 and T.R.M 2) produced in the reactor of oil catalytic cracking. The analysis of this waste was carried out. The properties of T.R.M 1 and T.R.M 2 were investigated and determined, the mineralogical analysis of catalyst waste was implemented, the analysis of thermal effects during the burning was performed. Catalyst waste materials investigated were used in a ceramic system (from 7 to 20 of the overall amount). It was identified that the optimal quantity of additive T.R.M 1 in formation mixes was 10%. With this amount of the additive, after the burning of formation mixes at 1050C temperature, ceramic systems with the following properties were formed: total contraction-up to 6.5, density of the system-larger than 1847 kg/m 3 , compressive strength-larger than 13 MPa, water absorption-up to 11 , and effective porosity-up to 21 . The identified optimum quantity of additive T.R.M 2 in the formation mix was 20 %. The obtained ceramic systems have the following parameters: total contraction-less than 10 %, density-higher than 1852 kg/m 3 , compressive strength-higher than 15 MPa, water absorption-less than 9 , and effective porosity-lower than 17 .
Nature communications, 2017
Since its commercial introduction three-quarters of a century ago, fluid catalytic cracking has been one of the most important conversion processes in the petroleum industry. In this process, porous composites composed of zeolite and clay crack the heavy fractions in crude oil into transportation fuel and petrochemical feedstocks. Yet, over time the catalytic activity of these composite particles decreases. Here, we report on ptychographic tomography, diffraction, and fluorescence tomography, as well as electron microscopy measurements, which elucidate the structural changes that lead to catalyst deactivation. In combination, these measurements reveal zeolite amorphization and distinct structural changes on the particle exterior as the driving forces behind catalyst deactivation. Amorphization of zeolites, in particular, close to the particle exterior, results in a reduction of catalytic capacity. A concretion of the outermost particle layer into a dense amorphous silica-alumina she...
Applied Catalysis A-general, 2002
This paper presents the results of an investigation carried out to experimentally determine the deactivation constant of a fluid catalytic cracking (FCC) process. Kinetic modeling was performed using a four-lump model and an experimentally determined deactivation constant. Significant improvement was achieved in predicting the product gasoline, gas and coke yields compared to the yields predicted by models using a theoretical deactivation constant. Activation energies for each reaction are reported and compared with the literature values. (M.A.-B. Siddiqui).