The co-production of liquid fuels, chemicals and electric power from our abundant United States Coal in a single, integrated facility can be, according to our United States Department of Energy, profitable.
And, such potentials for what is in some places referred to as "polygeneration" might come to be seen as much, much more economically important, even critical, as the realization that we don't have nearly as much shale natural gas economically accessible or recoverable as it's non-analytical and uncritical proponents would have had us believe dawns across our nation.
First, we remind you that divisions of the Eastman Chemical Company established some decades ago a Coal conversion plant in Kingsport, Tennessee, where syngas, a blend of Carbon Monoxide and Hydrogen, made by the gasification of Coal, is converted into fuel alcohol Methanol and other valuable chemicals.
A basic overview of the process is accessible via our prior report of:
Eastman Chemical Coal Gasification Overview | Research & Development | News; which centers on the graphic presentation: "Eastman Gasification Services Company: Eastman Gasification Overview; March 22, 2005; Eastman: Founded in 1920 as part of Eastman Kodak Wood-to-Methanol Plant; Gasification 101: Just the Basics: C + O2 + H2O = CO + H2; The partial oxidation of carbon to produce a 'synthesis gas'. What Is Gasification? Coal + Water + Oxygen = Carbon Monoxide + Hydrogen; Syngas = Building Blocks for Chemical Industry + Transportation Fuels + Clean Electricity; NGCC: Natural Gas Combined Cycle Plant; Most New Power Plants In The United States in the Last 10-15 Years Have Been Natural Gas Based; Integrated Gasification Combined Cycle: Replace Natural Gas Feed With (Coal-derived) Syngas".
And, we urge readers to make special note of the concluding lines in the above excerpts. Fortunately, as we will see in a few reports to follow, we do have some genuine patriots at work in the United States Department of Energy who are laying the groundwork for King Coal to ride to the economic rescue of those United States citizens who will more than likely find themselves, in the not-too-distant future, dependent upon electricity generated from natural gas - - electricity which they will no longer be able to afford.
Another passage in the above excerpts which arises from the concept of polygeneration noted in our introductory comments and which deserves attention is:
"Syngas = Building Blocks for Chemical Industry + Transportation Fuels + Clean Electricity".
As we've seen in a few other prior reports, such as:
Eastman Coal to Methanol and Electric Power | Research & Development | News; concerning: "United States Patent Application 20060096298 - Method for Satisfying Variable Power Demand; 2006; Inventor: Scott Barnicki, et. al., Kingsport, TN; Assignee: Eastman Chemical Company, TN; Abstract: A process for satisfying variable power demand and a method for maximizing the monetary value of a synthesis gas stream are disclosed. One or more synthesis gas streams are produced by gasification of carbonaceous materials and passed to a power producing zone to produce electrical power during a period of peak power demand or to a chemical producing zone to produce chemicals such as, for example, methanol, during a period of off-peak power demand. The power-producing zone and the chemical-production zone which are operated cyclically and substantially out of phase in which one or more of the combustion turbines are shut down during a period of off-peak power demand and the syngas fuel diverted to the chemical producing zone. This out of phase cyclical operational mode allows for the power producing zone to maximize electricity output with the high thermodynamic efficiency and for the chemical producing zone to maximize chemical production with the high stoichiometric efficiency. The economic potential of the combined power and chemical producing zones is enhanced"; and
Eastman Chemical Coal to Liquid Fuel, Chemicals and Electricity | Research & Development | News; concerning: "United States Patent Application 20070129450 - Process for Producing Variable Syngas Compositions; 2007; Inventors: Scott Barnicki, et. al., TN; Correspondence (and presumed eventual Assignee of Rights): Eastman Chemical Company, TN; Abstract: Disclosed is a process for the production of a variable syngas composition by gasification. Two or more raw syngas streams are produced in a gasification zone having at least 2 gasifiers and a portion the raw syngas is passed to a common water gas shift reaction zone to produce at least one shifted syngas stream having an enriched hydrogen content and at least one unshifted syngas stream. The shifted and the unshifted syngas streams are mixed downstream of the water gas shift zone in varying proportions (to) produce blended and unblended synthesis gas streams in a volume and/or composition that may vary over time in response to at least one downstream syngas requirement. The process is useful for supplying syngas from multiple gasifiers for the variable coproduction of electrical power and chemicals across periods of peak and off-peak power demand";
Eastman has been at work developing the technologies and processes which would enable the co-production of "chemicals such as, for example, methanol" and "electrical power" in a single, integrated industrial facility from, via an initial process of gasification, Coal.
And, herein we learn that the United States Department of Energy has studied the Eastman Coal conversion technologies, which can co-produce valuable chemicals and electric power from Coal, and has determined that they are not just feasible and practicable, but profitable.
Comment follows excerpts from the initial link in this dispatch to:
"DOE/NETL-2004/1199; Commercial-Scale Demonstration of the Liquid Phase Methanol (LPMEOH (TM)) Process; A DOE Assessment
U.S. Department of Energy Office of Fossil Energy; National Energy Technology Laboratory
(There can, as we perceive it, be some serious lag time between when projects and studies like this are completed, and when the USDOE makes reports of them accessible on the web. For example, we were only recently able to track down and access this document, even though, via:
Coal to Methanol - Eastman & Air Products | Research & Development | News; concerning an initial Eastman presentation: "Commercial-Scale Demonstration of a Liquid-Phase Methanol Process; Steven L. Cook; Eastman Chemical Company; Kingsport,TN 37662; Abstract: The Eastman Chemical Company operates a coal gasification complex in Kingsport. Tennessee. The primary output of this plant is carbonylation-derived acetic anhydride. The required methyl acetate is made from methanol and acetic acid. Methanol is currently produced from syngas ... . A liquid-phase methanol process (LPMEOH (TM)) has been developed by Air Products. Efficient heat removal permits the direct use of syngas without the need for the shift reactor. An Air Products/Eastman joint venture, with partial funding from the Department of Energy under the Clean Coal Technology Program, has been formed to build a demonstration-scale liquid-phase methanol plant. This talk will focus on the unique features of this plant and how it will be integrated into the existing facilities";
we were some time ago able to make an introductory report concerning the project itself, as it was publicly presented by Eastman Chemical Company, and noted that this was/is a joint undertaking by Eastman and Air Products and Chemicals, Inc.)
Executive Summary: The U.S. Department of Energy (DOE) Clean Coal Technology (CCT) Program seeks to offer the energy marketplace more efficient and environmentally benign coal utilization technology options by demonstrating these technologies in industrial settings. This document is a DOE post-project assessment (PPA) of one of the projects selected in Round III of the CCT Program, the Commercial-Scale Demonstration of the Liquid Phase Methanol (LPMEOH (TM)) Process.
Methanol is an important, large volume chemical with many uses. The desire to demonstrate a new process for the production of methanol from coal prompted Air Products and Chemicals, Inc. (Air Products) to submit a proposal to DOE. In October 1992, DOE awarded a cooperative agreement to Air Products to conduct this project. In March 1995, this cooperative agreement was transferred to Air Products Liquid Phase Conversion Company, L.P., a partnership between Air Products and Eastman Chemical Company (Eastman). Air Products, the technology supplier, provided the engineering design, procurement, construction, and commissioning of the 260-short tons/day LPMEOH (TM) Demonstration Unit. Eastman provided the host site, synthesis gas, and services to the unit, and served as the plant operator. Another team member, ARCADIS Geraghty & Miller, participated in the offsite fuel-use testing of stabilized methanol.
Operation of the LPMEOH (TM) Demonstration Unit began in April 1997. The demonstration unit is sited at Eastman’s chemicals-from-coal complex in Kingsport, Tennessee, which also contains a preexisting gas-phase methanol unit. Synthesis gas, also called syngas, a mixture of hydrogen (H2) and carbon monoxide (CO), was first introduced on April 2, and stable operation at design conditions was achieved on April 6. On April 10, a test run reached 115 percent of the design methanol production rate.
The LPMEOH (TM) process represents a major departure from traditional gas-phase routes to methanol in the method of removing the heat of reaction. The formation of methanol from syngas is highly exothermic. Because catalyst life is seriously reduced by excessive temperatures, reactor temperature control is very important. One of the most difficult design problems is removing the heat of reaction while maintaining precise temperature control. In conventional designs for gas-phase methanol reactors, the catalyst is present in a series of fixed beds, with cold feed gas being injected between beds to control temperature, or a heat exchanger type reactor is used with catalyst packed in the tubes and a coolant circulated on the shell side to remove heat.
In contrast, the LPMEOH (TM) process uses fine catalyst particles slurried in an inert mineral oil. The catalyst is kept in suspension by reactant gas, which bubbles up through the catalyst slurry. This type of reactor is typically referred to as a slurry bubble column reactor (SBCR). The mineral oil acts as a temperature moderator and a heat removal medium, transferring the heat of reaction from the catalyst surface to boiling water in an internal tubular heat exchanger. As a result of its capability to remove heat and maintain a constant uniform temperature throughout the reactor, the SBCR can achieve a much higher syngas conversion per pass, compared to a gasphase reactor. Side reactions produce small amounts of higher alcohols and other oxygenated compounds.
The LPMEOH(TM) Demonstration Unit was designed to have three feed-gas streams: balanced gas
(stoichiometric syngas with a H2/CO ratio of about 2.0), which is diverted from the feed to a preexisting gas-phase methanol unit; a high pressure CO stream, available from the Kingsport facility; and a hydrogen stream from the exit of the gas-phase unit. The hydrogen stream was not available, and was not used during this project; however, this did not impact the execution of the Demonstration Test Program. The fresh feed is mixed with recycled gas and sparged into the bottom of the reactor. Upon contact with the catalyst, methanol synthesis occurs.
Disengagement of the product gas (methanol vapor and unconverted syngas) from slurry occurs in the freeboard volume in the reactor above the slurry catalyst bed. The exit gas is cooled and condensed into liquid methanol, which is collected in a product separator. Part of the overhead stream from the separator is recycled to the reactor, and the rest is sent to the fuel gas header. The raw methanol stream is sent to a two distillation column recovery section. In the first column, dissolved gases are removed and sent to the fuel header. The underflow from this column is sent to the second distillation column, where purified methanol is recovered overhead.
The bottom stream, consisting of some methanol, higher alcohols, water, and mineral oil, is sent to the distillation system of the preexisting gas-phase unit for methanol recovery. The LPMEOH (TM) Demonstration Unit was designed to produce a refined-grade methanol product suitable for use in downstream applications at the Kingsport site.
The primary objective of this project was to demonstrate the production of methanol using the LPMEOH (TM) process, feeding syngas produced by an integrated coal gasification facility.
Specific technical objectives were:
- - To demonstrate the scale-up of the LPMEOH (TM) process slurry reactor from the 10-short tons/day scale at the DOE Alternative Fuels Development Unit (AFDU) in LaPorte, Texas, to a production rate of at least 260 short tons/day.
- - To demonstrate that the LPMEOH (TM) process, operating on a coal-derived syngas, compared favorably to conventional gas-phase processes in operability and economics.
- - To determine the suitability of methanol produced during this demonstration for use as a chemical feedstock, or as a low emission (sulfur dioxide (SO2) and nitrogen oxides (NOX))alternative fuel in stationary power generation and transportation applications.
- - To confirm commercial economics for the LPMEOH (TM) process for coproduction of once-through methanol, and integrated gasification combined cycle (IGCC) electric power.
(We've made previous report of "IGCC" technology, but mostly as an aside. Duke Energy provides a more complete synopsis/illustration of the concept via:
How IGCC Works -Duke Energy; "IGCC uses a coal gasification system to convert coal into a synthesis gas (syngas) and produce steam. The hot syngas is processed to remove sulfur compounds, mercury and particulate matter before it is used to fuel a combustion turbine generator, which produces electricity. The heat in the exhaust gases from the combustion turbine is recovered to generate additional steam. This steam, along with that from the syngas process, then drives a steam turbine generator to produce additional electricity".
We'll note that there are multiple ways in which "additional electricity" can be generated in processes like IGCC combined with Methanol synthesis, such as recovery of heat energy from the syngas as well as combustion of the syngas.).
During the performance period, the unit produced almost 104 million gallons of methanol, all of which was accepted by Eastman for the production of methyl acetate, and ultimately cellulose acetate and acetic acid.
Average availability of the unit from April 1997 through December 2002 was 97.5 percent.
Two potential applications of stabilized methanol were investigated: transportation systems and power generation systems. In vehicle trials, stabilized methanol provided the same environmental benefits as chemical-grade methanol with no penalty on performance or fuel economy. Tests in a gas turbine and a diesel generator showed that levels of NOX in the exhaust
A very interesting concept is to couple a methanol plant with a coal-based IGCC facility. In this concept, part of the syngas produced by the coal gasifier is sent to the methanol plant. If the methanol plant is flexible enough to accept a varying feed stream, this option would permit the gasifier - - the largest capital cost item in the facility - - to operate at a constant rate, regardless of electric power demand.
Excess syngas could be sent to the methanol unit, whose production rate would vary inversely with electric power demand. If more power were required than could be satisfied by the gasifier, some of the stored methanol could be burned in gas turbines. Operation of the LPMEOH (TM) Demonstration Unit has generated data to assist in evaluating the technical and economic merits of this concept.
To be most efficient, the methanol plant in such a complex should be able to operate on low H2/CO molar ratio syngas, typical of that produced by a coal gasifier. Gas-phase reactors are not well adapted to this type of syngas, because of the high heat of reaction. However, the LPMEOH (TM) process, which uses a slurry-phase reactor with an inherently high heat removal capability, is well suited to this application.
Thus, this project was very important in establishing the commercial readiness of the LPMEOH (TM) process and its applicability to coproduction (production of both electric power and methanol) operations.
Tests made during the demonstration project confirmed that a LPMEOH™ process unit has the capability to operate satisfactorily in a coal-based IGCC environment, in that it has the capability to operate on a syngas with a range of H2/CO ratios, on/off, and ramping modes. These capabilities are necessary to adjust the varying syngas feed rate that results from the power plant’s following the electrical demand. As electrical demand varies, the amount of syngas available for conversion to methanol also varies. The unit was able to achieve at least a 5 percent change in feed rate per minute during ramping, showing that the process is very flexible and stable.
The success of this project can be attributed to the following reasons: unit design based on high quality data from test units; good cooperation among all parties involved; well thought out test plan; well qualified operating crew; and a highly competent engineering staff, able to solve problems as they arose.
The potential for coal-based IGCC in the U.S. could be as high as 60 GW by 2020 (DOE 2002). If coproduction were able to capture 10 to 20 percent of this market, there would be considerable opportunity for installing the LPMEOH (TM) process.
Methanol produced by coal-based IGCC operations should be lower cost than methanol produced by conventional methanol-only units, and could displace higher priced methanol from other sources".
There is, in fact, a second volume to the final report of this project which, as we take it, treats the economics in more depth. But, as we indicated in our introductory comments, there is a lag between when reports of projects like this are published and when they are made freely available on the web. When we are finally able to track down the second volume, with a presumably more complete exposition of the economics, we will make report of it.
However, in closing, we remind you of a follow-on process, which might make the Methanol, and this technology for producing it from Coal, more valuable than it's current use by Eastman for making "methyl acetate, and ultimately cellulose acetate and acetic acid". As seen for one example in:
"United States Patent 4,348,486 - Production of Methanol via Catalytic Coal Gasification; 1982; Inventor: William Calvin, et. al., NJ; Assignee: Exxon Research and Engineering Company"; and:
"United States Patent 4,035,430 - Conversion of Methanol to Gasoline; 1977; Inventor: Francis Dwyer, et. al., NJ and PA; Assignee: Mobil Oil Corporation";
Methanol, as made "at lower cost" from Coal along with a certain amount of electric power, as herein, can also be directly and efficiently converted into all-American, non-OPEC Gasoline.