Production of Gasoline from Syn Gas
Client/Mentor
Dan Rusinak- Middough
Team Alpha
Ayesha Rizvi
Bernard Hsu
Jeff Tyska
Mohammed Shehadeh
Yacoub Awwad
Table of Contents
1. Abstract 3
2. Executive Summary 4
3. Discussion 7
4. Recommendations and Conclusions 9
5. Appendices 10
A. Design Basis………………………………………………………………………………………………………………………………10
1. Abstract
One of the largest problems facing this country is the current energy crisis. World oil production peaked in 2005, and prices have been going up in recent years. Much of the U.S.’s oil is also imported, leading to reduced energy independence. Due to this crisis, many methods of producing liquid fuels for transportation and heating are being researched. One way to help abate the current problem is to make gasoline and liquified petroleum gas (LPG) from renewable sources. Our project will take municipal solid waste-derived syngas (H2 and CO) and convert it into gasoline, which can be blended in a refinery, and LPG, which can be used for heating or as a fuel for specially modified automobiles. Our gasoline and LPG will also have a smaller carbon footprint than fossil fuel derived gasoline and LPG. By using this process, a renewable and local fuel can be produced which will fit into the current infrastructure. The first step of our process will be taking syngas with an H2 to CO ratio of 2:1 and turning it into Methanol. Most of the Methanol then will be converted to dimethyl ether (DME) and water. Methanol and DME will then react to produce a mixture of hydrocarbons. Hydrocarbons will be separated by distillation, and a product stream of C5+ gasoline and LPG will be produced and sold. Our process is based upon the Mobil Process, which has been demonstrated in a plant in New Zealand which produced about 14,000 barrels of gasoline per day.
2. Executive Summary
In the United States, gasoline is derived from the processing of oil. In 1970, domestic production of oil peaked and imports sharply rose, and by 1995, oil imports had exceeded domestic production. A barrel of oil constitutes 42 gallons. On average, according to United States Energy Information Administration (EIA), 19.36 gallons of gasoline are generated from a single barrel of crude oil. This means that 43% of a barrel of oil translates to gasoline. (cite http://tonto.eia.doe.gov/country/index.cfm?view=production) . The EIA stated in 2009, Americans used 3.3x109 barrels of gasoline—about 1.38x1011 gallons in a single year.
Figure 2-1
Consequently, the prices of gasoline peaked on July 4, 2008 at a national average of $4.11/gallon as shown in Figure 2-2. The prices dropped sharply in Q1 2009, however have ever since been on the increasing trend once again. Because of international crises littering the Middle East in 2011, and with the United States becoming ever increasingly dependent on imported, foreign oil, the price of oil is largely variable, thus leading to unstable prices in gasoline. Energy independence is thus an impeccable and indispensible quality that must be pursued with rigorous research and innovation. The first step towards energy independence would be to produce gasoline, the largest use derived from crude oil, from renewable resources.
Figure 2-2
The project begins with syngas obtained from municipal solid waste. The syngas is delivered to our chemical production plant in a 2:1 H2:CO ratio and Methanol is produced. The aim is to produce gasoline components, mainly C5+ hydrocarbons from Methanol. The process aspires to produce 3000 tons per day of Methanol, which will be used to produce 2300 barrels per day of C5+ Gasoline and 7700 lbmol per day of LPG. The MTG process will run in three reactors in parallel and will use the ZSM-5 catalyst. The Methanol reactor will be modeled as a shell and tube heat exchanger using the typical copper/zinc/alumina catalyst. (Talk briefly about heat exchangers, steam production, etc)
Highlight economics here and give what the large costs will be and what revenue will be
Talk about location and talk about the NZ plant
3. Discussion
Municipal solid waste (MSW) is largely a renewable resource. The average American generates 650 times their bodyweight in trash throughout their lifetime. Questions asked about how landfill space can be dealt with. Converting MSW to syngas is an efficient way of converting waste into a useful chemical precursor for producing other important industrial chemicals.
Syngas at a 2:1 H2:CO ratio is fed to a methanol reactor where the reaction occurs as:
2H2 + CO à CH3OH (1)
This reaction occurs at 725 psi, 270ºC and 99.5% selectivity. The Methanol for the Methanol-to-Gasoline (MTG) process needs not be purified as in a traditional methanol production process, so therefore distillation columns are not a part of the methanol production portion of the process. In fact, the MTG process will convert the byproducts that may come out of the methanol reactors, mainly light hydrocarbons and CO2, and since the selectivity of the reaction runs at 99.5%, the presence of these other components is in small concentration. The Methanol reactor is modeled as a shell and tube heat exchanger jacketed pressure vessel. For the reactor, the catalyst is on the tube side and since (1) is exothermic, the diameter of thetube side will be larger for the same amount of catalyst put in a traditional tank reactor. The methanol reactor runs at a conversion of 0.4, so the effluent will contain methanol, other components, and syngas. The effluent will be at high temperature (please cite) and this hot product will need to be cooled in order to separate the methanol from the syngas. The heat removed will be used to generate steam. The syngas separated from the methanol reactor effluent is part of both a purge stream and a recycle stream. About 2% of the syngas will be recycled back to the methanol reactor and the purge stream is to maintain the 2:1 H2:CO ratio of the feed. The methanol portion of the effluent will be reheated and then sent to the MTG reactors.
In the MTG process, methanol is reacted over the ZSM-5 catalyst in a fluidized bed reactor. Three MTG reactors in parallel are used. The ZSM-5 catalyst was patented by Mobil in 1972 (U. S. Patent 3,702,886) and costs $1.50/lb undoped. In the MTG process, the reactor is run at 330ºC at the inlet and 400ºC at the outlet and the pressures at the inlet and outlet are at 210 and 185 psia respectively. The effluent of the MTG reactors will produce streams of both Liquefied Petroleum Gas (LPG) and gasoline components (C5+). LPG will be sold for various heating purposes and thus the price is modeled as if it were natural gas.
The MTG process yields (please correct this) roughly 56 wt% water and 44 wt% hydrocarbons. NEED NEW COMPONENT BALANCE