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Production of Synthesis Gas & Ethanol Presented By : (Group 1) Beshayer Al-Dihani Hessa Al-Sahlawi Latifa AL-Qabandi Supervised By: Prof. Mohamed A. Fahim Eng. Yusuf Ismail Ali Contents • • • • • • • Abstract Introduction Production of Synthesis Gas Uses of Synthesis Gas Production of Ethanol Uses of Ethanol Conclusion Abstract There are three methods for product synthesis gas: First, synthesis gas produce by steam reforming from natural gas. • Second, is the partial oxidation from natural gas. • Third, is partial oxidation from vacuum residue. • Synthesis gas is used as raw material to produce Ethanol. Introduction • Synthesis gas generally refers to mixture of carbon monoxide and hydrogen. The ratio hydrogen to carbon monoxide varies according to the type of feed, the method of production, and the end use of the gas. • Natural gas: Natural gas is a vital component of the world's supply of energy. It is the cleanest, safest and most useful of all energy sources. It is consumed in residential, commercial, industrial and utility market. The different sources and routs to synthesis gas Steam Reforming Natural Gas Coal Gasification Synthesis Gas (Co, H2 Mixture) Partial Oxidation Of natural gas & Petroleum products Steam Reforming Petroleum Products Method (1): Steam reforming For Synthesis gas Production from Natural gas:- • Catalytic steam reforming is used to convert hydrocarbon feeds to synthesis gas by reaction with steam over a nickel – based catalyst. • The process is usually operated between 800˚C and 1000 ˚C (1500 – 1800 ˚F) and 8 to 25 bars (100_350 psig) . • For our process the raw materials are : • CH4,C2H6,C3H8,CO2,N2,O2,H2O • The reactions are : • CH4 +H2O CO +3H2 • CH4 +2H2O + CO2 4CO +8H2 • It is an endothermic reaction • The final product are : • CH4,CO2,CO,H2,N2,H2O Reformer Reactor / Furnace • The reformer is a direct fired chemical reactor consisting of numerous tubes located in fire box and filled with catalyst. • Conversion of hydrocarbon and steam to an equilibrium mixture of hydrogen, carbon oxides and residual methane takes place inside the catalyst tubes. • Heat for the highly endothermic reaction is provided by burners in the firebox. • The heat is transferred to the catalyst filled reactor tubes by a combination of radiation and convection. • Reforming catalyst is available in many shapes and sizes, each with specific advantages according to the suppliers. Different types and shapes of catalyst • Figure (5) is a flow sheet illustration of our process concept for the production of synthesis gas (H2: CO ratio 2:1) by the steam reforming of natural gas. • process is divided into three sections: • Steam reforming and heat recovery (section 100). • Carbon dioxide separation (section 200). • Hydrogen skimming (section 300). Figure(5) Method (2): Production of synthesis gas (H2:CO=2:1) from natural gas by partial oxidation This process takes place @ high temperature and pressure, but no catalyst. The reaction is called partial oxidation because it is kept from going to CO2 by limiting the amount of oxygen fed to process. • • • • • • • For our process the raw materials are : CH4,C2H6,C3H8,CO2,N2,O2,H2O The reaction is : CH4 +½ O2 CO +2H2 It is an exothermic reaction The final product are : CH4,CO2,CO,H2,N2,H2O • Figure (7) is a flow sheet illustration of our process concept for the production of synthesis gas (H2: CO ratio 2:1) by the partial oxidation of natural gas. • process is divided into three sections: 1. Partial oxidation and heat recovery (section 100). 2. Air separation (section 200). 3. Carbon dioxide separation (section 300). Figure(7) Method (3): Synthesis gas (H2: CO = 2:1) from vacuum residue by partial oxidation: Process for the non – catalytic partial • oxidation of hydrocarbons were primarily developed for the gasification of heavy petroleum feedstock's at the bottom of the barrel, which can contain high levels of sulfur and metallic oxides. The feedstock's for the feed are : Carbon,Hydrogen,Nitrogen,Sulfur Ash,oxygen and water. The reaction were take place in the process are : CnHmSr + n/2 O2 nCO + ( m/2-r)H2 +rH2S CO + ½ O2 CO2 CO + H2O CO2 + H2 COS + H2 CO + H2S COS + H2O CO2 + H2S ( CH2 ) n ( CH4 ) n/2 + C n/2 CH4 + H2O CO + 3 H2O C+ CO2 2 CO C + H2O CO + H2 the reaction are exothermic Process Description: The process is divided to four sections: 1- Partial oxidation and heat recovery (section 100). 2- Air separation (section 200). 3- Soot recovery and recycle (section 300). 4- Acid gas removal, CO shift, and sulfur recovery (section 400). First , in the Air separation section the oxygen are produced with 99.5 vol% purity . Second , in the soot recovery and recycle section the Naphtha stripper recycle are produced which is fed to oxidizer reactor . Third, in the partial oxidation and heat recovery section the vacuum feedstock's is fed to reactor with blend of steam , oxygen form air separation section and recycle Naphtha , the hot product are quench in heat recovery then scrubbed with water so that can send to soot recovery section and Acid gas removal ,co shift and sulfur recovery section . Final, in the Acid gas removal ,co shift and sulfur recovery section the CO2 and sulfur are removed and the syngas will produce. Partial oxidation and heat recovery (section 100) Air separation (Section 200) Soot Recovery and Recycle (Section 300) Acid Gas Removal and CO shift (Section 400) Synthesis gas by other methods: By coal gasification: Manufacture of synthesis gas was based on coal for many years before the introduction of steam reforming, and in west Europe coal–based production remained dominated until the 1960s. The original method was generation from coke, by the water gas reaction: C + H2O CO + H2 (c. 1200 C) The heat required for this endothermic reaction is providing by burring some of the coke: C + O2 CO2 Operation is cyclic, with air and stream alternately being blown through a bed of coke. The process is extremely wasteful of coke and of energy. More sophisticated and efficient are coal gasification processes, in which coal is treated with mixture of oxygen, or air, and steam: (O2, H2O) Coal CO + H2 (750- 1500 C) Capital and operation costs for coal–based manufacture of synthesis gas are much higher than those for manufacture by steam reforming largely because coal is solid. There is one country, south Africa, where manufacture of synthesis gas from coal has never been displaced by steam reforming. Uses of synthesis gas The chief use of syngas is in: 1. the manufacture of hydrogen for a growing number of purposes. 2. Methanol not only remains the second largest consumer of syngas but has shown remarkable growth as part of the methyl ethers used as octane enhancers in automotive fuels. 3. The hydroformylation of olefins (the oxo-reaction), a completely chemical use of syngas. Uses of synthesis gas 4. The Fischer-Tropsch synthesis remains the third largest consumer of syngas, mostly for transportation fuels. 5. generation of electricity. 6. Syngas is the principal source of carbon monoxide, which is used in an expanding list of so-called carbonylation reactions. Production of Ethanol from Syngas • Ethyl alcohol has been produced by fermentation of carbohydrates of many thousands of years. • Economic industrial manufacture of synthetic ethyl alcohol began in the 1930s. • The first process used was the indirect catalytic hydration of ethylene. • This route has several disadvantages: • The large volumes of dilute sulphuric acid to be handled. • The energy required for its concentration. • Corrosion caused by the acid. alternative routes based on methyl alcohol or synthesis gas as starting materials has been developed. Carbonylation Syngas Methanol Hydrolysis Acetic Acid Ethanol Another rout was developed to: Syngas RH Ethanol • The process was shown to be uneconomic: • Inadequate selectivity to ethanol • The very large amounts of rhodium catalyst required. • SRI presents a speculative design for an alternative process to produce ethanol from synthesis gas. • The process uses a copper-cobalt catalyst • Conversion of synthesis gas to ethanol can be carried out directly 4H2 + 2CO CH3CH2OH + H2O • The reaction is exothermic, with a heat of reaction of -57.2 kcal/g-mol. • Examples using these catalysts mention the presence of carbon dioxide in the feed synthesis gas. • The carbon dioxide can react with hydrogen as follows: • 6H2 + 2CO2 CH3CH2OH + 3 H2O • This reaction is exothermic, with a heat of reaction - 37.5 kcal/g-mol. Process Description • The plant is designed to produce ethanol as the principle product, in the presence of the catalysts (mixture of oxides of Cu, Co, Cr and K). • The design that we will discuss has two sections: • Reaction section. • Separation section. • Fifteen days’ product storage is provided for ethanol, methanol, and mixed C3 alcohols. Storage is provided for 48 hours of both the gasoline feed to the extraction unit and gasoline-plus-C4+ alcohols product. Summary of the process • Feed is H2, CO, CO2 and N2. • The products from reaction section are H2O, methanol, ethanol, propanol, butanol, pentanol, hexanol and heptanol. • The final products are methanol, ETHANOL and propanol. Uses of Ethanol Medically, ethanol is: • a soporific, i.e., sleep producing; although it • less toxic than the other alcohols, death usually occurs if the concentration of ethanol in the bloodstream exceeds about 5%. Uses of Ethanol • Ethanol is used: • In the manufacture of alcoholic drinks. • As a solvent for paint, varnish and drugs. • In the manufacture of acetaldehyde and acetic acid. Uses of Ethanol • As a fuel (e.g. in Gasahol). • As the fluid in thermometers. • In preserving biological specimens. • Ethanol is also used in design and sketch art markers CONCLUSION • We conclude that there are many ways to produce synthesis gas: • Stem reforming from natural gas. • Partial oxidization from natural gas and from vacuum residue. • There are many ways to produce ethanol, but we choose direct synthesis method from syngas. Thank you for your attention