Jignesh Panchal and Jeffrey Rolle, A J Edmond Company, Presented at Presented at the Electrode Technology for Aluminum Production, TMS 2012, March 2012.
Vibrated Bulk Density (VBD) of calcined petroleum coke is widely utilized as one measure of quality and is useful for quantifying binder demand in the anode production process of the aluminum reduction industry. ASTM D 4292-10 is one of the methods used widely by the carbon and aluminum reduction industries to measure VBD. Recently the carbon producer and consumer industries have jointly worked together to increase the competence and benefit of this method. Geopyc is a semi-automated device that potentially yields better precision compared to traditional vibrator device specified in D 4292. This paper presents an innovative use of the Geopyc instrument in measuring VBD, the results of which correlate well with D 4292; especially to the 28×48 Tyler Mesh size fractions. This novel sample preparation does not involve complicated roll crushing steps as specified in the ASTM method(s) and thus simplifies the method while improving the accuracy and precision.
Max Casada, Venco, P.O. Box 577, State Route 2, South Moundsville, WV 26041; Jeff Rolle, A.J. Edmond Co., 1530 West 16th Street, Long Beach, CA 90813; Chris Eppig, Dr. Steve Paspek, BP Oil Company, 4440 Warrensville Center Road, Cleveland, OH 44128-2837; Zeno DeMori, ORMET, P.O. Box 176/State Route 7, Hannibal, OH 43931; Gary Force, BP Oil Company, 200 Public Square, Cleveland, OH 44114; Jaime Mora, Juan Turpial, Venalum, CVG Industria Venezolana De Aluminio, C.A., Zona Industrial Matanzas, Estado Bolivar, Venezuela; David Hester, Conoco Inc., 1000 South Pine, Ponca City, OK 74602; Mirna Chirinos, Francisco Perez, Alcasa, CVG Aluminio Del Caroni S.A., Zona Industrial Matanzas, Estado Bolivar, Venezuela; Julio Velasco, Venco URB Villa Asia, Calle Bombay Manz. 27, #10, Puerto Ordaz, Bolivar, Venezuela; Eli Epstein, Don Pirolo, Venco, 600 N. Dairy Ashford, Houston, TX 77252
The concentration of various metallic compounds in crude oils and in the resulting petroleum coke has continued an upward trend as crude reserves continue to change and tend toward being increasingly heavy and sour. Traditionally labeled as a catalyst, nickel has been included with vanadium in the evaluation of its effects on anode reactivity. In 1995, a Task Force was formed to quantify the influence of nickel on reduction cell anodes as existing information in the literature did not address specifically the affects of varying concentrations of nickel on anodes. The task force prepared resid with identical properties with the exception of nickel content. These resids were then coked, calcined, and formed into anodes in as identical a process as possible. Finally, the anodes were baked and tested to determine the effects on their performance characteristics. The results and conclusions drawn from this process will be communicated in this paper.
Studies of the Impact of Vanadium and Sodium on the Air Reactivity of Coke and Anodes, Authors Jeffrey Rolle and Yen Hoang, Presented at the 1995 Light Metals Carbon Technology Session, March 1995.
Many significant studies have been published which examined the impact of vanadium and sodium on the air reactivity of coke and anodes. Most studies have compared different coke with differing levels of vanadium and sodium to make inferences about their impact on coke and anode quality. The studies discussed in this paper involve a single coke with different level of vanadium and sodium (effectively holding other variables constant). Inferences drawn are therefore based on direct responses to variable studied.
Reduced levels of vanadium were achieved by hydrotreating coker feedstock. Increased levels of vanadium were achieved by spiking coke feedstock with organometallic vanadyl porphyin compound. Sodium levels were affected in variety of ways. Results indicate that vanadium has less impact on air reactivity then previously published and that sodium is approximately five time more leveraging then vanadium on both coke and anode air reactivity.
Historical and Future Challenges with the Vibrated Bulk Density Test Methods for Determining Porosity of Calcined Petroleum Coke:
Jignesh Panchal; Mark Wyborney; Jeffrey Rolle; A.J.Edmond Company, Presented at the Electrode Technology for Aluminum Production, Petroleum Coke VBD session at TMS 2011, March 2011.
Over several decades, calcined petroleum coke producers and the aluminum industry have been using various techniques such as Vibrated Bulk Density (VBD), Mercury Intrusion Porosimetry (MIP), and Mercury Apparent Density to predict the porosity of calcined petroleum coke. Better knowledge of the coke porosity allows a more accurate estimation of coke quality and pitch demand for fabricating anode of optimum performance. Industry has had limited success in accurately predicting porosity using the existing VBD methods. Direct measurement of porosity by MIP is an alternative way to measure porosity accurately. Currently there is limited correlation between VBD and MIP. Any improvements to the VBD test method should demonstrate improved correlation to the results obtained from MIP. This paper covers the historical and traditional approach to predict calcined coke porosity, correlation study of VBD test method and porosity by MIP, and input to the development of superior test methods to meet Industry requirements.