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Polypropylene reinvented: Costs of using metallocene catalysts

Description: This study develops scoping estimates of the required capital investment and manufacturing costs to make a zirconocene catalyst/cocatalyst system [(F{sub 6}-acen)Zr(CH{sub 2}CMe{sub 3})(NMe{sub 2}Ph)][B(C{sub 6}F{sub 5}){sub 4}] immobilized on a silica support. Costs for this fluorine-based system are compared with estimates for two other metallocene catalysts using methylaluminoxane (MAO)-based cocatalysts. Including wt of support and cocatalyst, each of the production facilities for making the 3 zirconocene catalyst systems is sized at 364--484 tonnes/year. Cost to make the F-based catalyst system is estimated to be $10780/kg, assuming 20% return on capital invested. Costs for the two MAO-based catalyst system fall in the range of $10950--12160/kg, assuming same return. Within the {plus_minus}50% accuracy of these estimates, these differences are not significant. Given a catalyst productivity of 250 kg resin/gram zirconocene, the cost contribution in the finished ethylene-propylene copolymer resin is 4.4 cents/kg, excluding selling, administrative, research costs.
Date: May 1, 1996
Creator: Brockmeier, N.F.
Partner: UNT Libraries Government Documents Department

Scoping economics for the commercial manufacture of metallocene catalysts

Description: This study assumes that commercial-scale production of propylene-based isotactic polymers with metallocene catalyst systems will become a reality. The challenge that must be overcome for commercial success with these propylene polymers is to discover a metallocene system recipe that will give sufficient catalyst activity along with the requisite stereo-selectivity at reasonable cost. Anticipating such a discovery, it is assumed here that the economics are well-represented by a catalyst system that consists in part of a silylene-bridged cyclopentadienyl zirconocene made in a batchwise process having an annual capacity of 15,000 pounds. Activation will be achieved with a cocatalyst such as methylaluminoxane (MAO), coated in conjunction with the catalyst on a support such as silica. The MAO at an estimated $100/lb contributes $1800/lb cost to the finished catalyst with an assumed recipe of 18:1 mass ratio of MAO to zirconocene. Based on a 20% return on investment, the selling price for the supported zirconocene system is estimated to be $2915/lb. The required capital investment to make 735,000 lb/yr of the total supported system is 9 million dollars. These estimates have {plus_minus}50% range of uncertainty. Payback period for this plant in a sold-out condition is three years. The catalyst system cost in ethylene-propylene copolymer is 3.9 cents per pound with a productivity of 75,000 lb polymer/lb of zirconocene. An Appendix includes some economic details.
Date: May 26, 1994
Creator: Brockmeier, N. F.
Partner: UNT Libraries Government Documents Department

Recovery of recyclable materials from shredder residue

Description: Each year, about 11 million tons of metals (ferrous and nonferrous) are recovered in the US from about 10 million discarded automobiles. The recovered metals account for about 75% of the total weight of the discarded vehicles. The balance of the material or shredder residue, which amounts to about 3 million tons annually, is currently landfilled. The residue contains a diversity of potentially recyclable materials, including polyurethane foams, iron oxides, and certain thermoplastics. This paper discusses a process under development at Argonne National Laboratory to separate and recover the recyclable materials from this waste stream. The process consists essentially of two-stages. First, a physical separation is used to recover the foams and the metal oxides, followed by a chemical process to extract certain thermoplastics. Status of the technology is discussed and process economics reviewed.
Date: January 1, 1994
Creator: Jody, B.J.; Daniels, E.J.; Bonsignore, P.V. & Brockmeier, N.F.
Partner: UNT Libraries Government Documents Department

CO{sub 2} capture for PC boilers using flue-gas recirculation : evaluation of CO{sub 2} recovery, transport, and utilization.

Description: The U.S. Department of Energy (DOE) is investigating retrofitting boilers with flue gas recirculation as a strategy for CO{sub 2} recovery from conventional pulverized coal (PC) plants because of the current motivation to reduce greenhouse gas emissions. However, this technology was conceived nearly twenty years ago at Argonne National Laboratory as a low-cost CO{sub 2} source for enhanced oil recovery (EOR). The fundamental concept is to replace combustion air with oxygen diluted by recirculated CO{sub 2} from the flue gas. This eliminates N{sub 2}-CO{sub 2} separation, permitting more economical CO{sub 2} recovery than competing amine systems. A molar ratio of CO{sub 2}/O{sub 2} of {approx}3 is necessary to preserve the heat transfer performance and gas path temperatures, allowing this system to be applied as a retrofit.
Date: March 4, 2002
Creator: Doctor, R. D.; Molburg, J. C.; Brockmeier, N. F. & Mendelsohn, M.
Partner: UNT Libraries Government Documents Department

Cryogenic separation of CO{sub 2} from the fluegas of conventional coal-fired power plants

Description: The reduction of CO{sub 2} emissions to the atmosphere is under study because such emissions are believed to contribute to undesired global warming via the greenhouse effect. Several conceptual processes for the capture of CO{sub 2} from power-plant flue gas are listed, with an emphasis on refrigeration and compression as a promising process to compete with amine absorption. At conditions that are industrially achievable (temperature of 170 K and pressure of 5 bar), CO{sub 2} forms a nearly pure solid on cooling from an impure mixed vapor. This study relies on this freezing and purification process to remove 90% or more of the CO{sub 2} from flue gas. Thermal and mechanical integration are used in the conceptual flow sheet to achieve better efficiency. A computerized process simulator, Aspen Plus with Model Manager{reg_sign}, is used to rigorously calculate the material and energy balances for the conceptual process. Key parameters are regressed from the component physical properties of the flue gas and used by the computer in the Peng-Robinson equation of state to quantify the required phase changes of CO{sub 2} solid between vapor and liquid states. Results of process evaluation are given over a range of operating conditions: pressures from 2 to 25 bar and temperatures from 150 to 220 K. This CO{sub 2} separation is shown to be technically feasible by using relatively simple and compact heat-exchange and compression equipment, with an energy requirement of 0.54 kWh/kg CO{sub 2}, even without optimization. For comparison, the energy used by state-of-the-art amine absorption is 0.43 kWh/kg. In spite of the 25% higher energy requirement for a cryogenic separation plant, the expectation is that it should have a 4% lower cost per tonne of avoided CO{sub 2} because it is estimated to require a much lower capital investment than amine absorption.
Date: February 1, 1995
Creator: Brockmeier, N. F.; Jody, B. J.; Wolsky, A. M. & Daniels, E. J.
Partner: UNT Libraries Government Documents Department

A process to recover plastics from obsolete automobiles by using solvents at ambient pressure

Description: Recycling of the metal content of obsolete vehicles has been actively pursued since the 1950s; today, obsolete automobiles are the single largest source of scrap iron. They contribute over 25% of the 36 metric tonnes (40 million short tons) of ferrous scrap recovered annually by the secondary metals industry and used in the production of finished steel products. They also contribute over one million metric tonnes (1.1 million short tons) of nonferrous metallic scrap a year for recycling. For each ton of metals recovered, about 500 lb of nonmetallic residue or waste is co-produced. Auto shredder residue (ASR) is a very heterogeneous mixture of solids and liquids. Table I lists most of the materials that are commonly present in the ASR are listed. We have developed and tested in the laboratory a three-step process to separate thermoplastics, and other potentially recyclable products, from ASR. The process involves a drying step followed by a mechanical separation step to concentrate the thermoplastics by separating the polyurethane foam and the fines, which are mostly metal oxides and other inert materials that are smaller than 0.62 cm (0.25 in.) in size. The concentrated plastics stream is then treated with organic solvents at ambient pressure and elevated temperatures to dissolve the desired plastics. The salient features of the process are described.
Date: August 1, 1993
Creator: Jody, B. J.; Daniels, E. J.; Bonsignore, P. V. & Brockmeier, N. F.
Partner: UNT Libraries Government Documents Department

An Overview of hydrogen production from KRW oxygen-blown gasification with carbon dioxide recovery

Description: All the process elements are commercially available to operate coal gasification so that it can produce electricity, hydrogen, and carbon dioxide while delivering the same quantity of power as without H{sub 2} and CO{sub 2} recovery. To assess the overall impact of such a scheme, a full-energy cycle must be investigated (Figure 1). Figure 2 is a process flow diagram for a KRW oxygen-blown integrated gasification combined-cycle (IGCC) plant that produces electricity, H{sub 2}, and supercritical CO{sub 2}. This system was studied in a full-energy cycle analysis, extending from the coal mine to the final destination of the gaseous product streams [Doctor et al. 1996, 1999], on the basis of an earlier study [Gallaspy et al. 1990]. The authors report the results of updating these studies to use current turbine performance.
Date: August 31, 2000
Creator: Doctor, R. D.; Brockmeier, N. F.; Molburg, J. C.; Thimmapuram, P. & Chess, K. L.
Partner: UNT Libraries Government Documents Department