300 likes | 607 Views
Kuwait University College of Engineering and Petrolume Chemical Engineering Department Plant Design ChE 491. Ethanol Production from Carbon Dioxide. group # 3 Presented By: Fatma Jawad Jarkhi Dana Saad Almyias Fatma Mahmood Abul. Supervised By: Prof. Mohamed A. Fahim
E N D
Kuwait University College of Engineering and Petrolume Chemical Engineering Department Plant Design ChE 491 Ethanol Production from Carbon Dioxide group # 3 Presented By: Fatma Jawad Jarkhi Dana Saad Almyias Fatma Mahmood Abul Supervised By: Prof. Mohamed A. Fahim Eng.Yusuf Ismail Ali
Outline : - Introduction . - Chemical Properties. - Physical Properties . - Sources of Carbon Dioxide . - Capture of Carbon Dioxide. - CO2 capture technologies. - Greenhouse Gases and its effect. - Uses and utilization of Carbon Dioxide. - Ethyl alcohol.
Greenhouse Gases and its effect : -The greenhouse gases are carbon dioxide, methane, water vapor, and nitrous oxide. - When the concentration of these gases increases, they will absorb heat from the sun light, that will cause global warming. - Global Warming means increasing in the temperature of the earth and the oceans.
Introduction : • Carbon dioxide is a chemical compound composed of one carbon and two oxygen atoms with a chemical formula CO2. • Carbon dioxide content in fresh air varies between 0.03% (300 ppm) and 0.06% (600 ppm ) . • - The carbon dioxide which is present in the atmosphere is produced by respiration and by combustion.
Chemical Properties: - Carbon dioxide reacts with water to form acid, also reacts with alkalis to give carbonates and bicarbonates. - Carbon dioxide gas is very dense and non-flammable.
- Physical Properties: - Carbon dioxide is a colorless, odorless gas, slightly toxic, which is soluble in water, in ethanol and in acetone. - Carbon dioxide is dangerous when inhaled in high concentrations affects human health .
Sources of Carbon Dioxide : * Natural Sources: Include respiration system,Oceanatmosphere exchange and Volcanic eruptions . * Industrial Sources in Kuwait : - Fossil Fuel Combustion in Thermal Power Plant. - Refineries . - EQUATE Company .
Total Amount of CO2 emitted in Kuwait by different sources :
Capture of Carbon Dioxide The main techniques are : • 1. Pre-Combustion Capture : • - It’s built on the gasification of the fuel where the fuel is first converted into gas by heating it with steam and air or oxygen . • - This conversion produces a gas containing mainly hydrogen and CO2, which can be quite easily separated out. • 2. Post-Combustion Capture: • - Flue gas produced by combustion of the fuel with air only contains a small fraction of CO2. • - It is captured by injecting the flue gases in a liquid that selectively absorbs the CO2.
Absorption: Based on using Chemical and physical solvents to separate the CO2 from the gas stream. 1- Chemical Absorption: - The stream containing CO2 is cooled and impurities are removed. - CO2 will be absorbed by the chemical solvent in the absorber. - The CO2 rich solvent will pass through the stripper where it is heated with the steam to release pure CO2, that will be compressed for storage, while the solvent will recycle to the absorption vessel.
1- Amines: - Menoethanolamine (MEA). - diethanolamine (DEA). - diisopropanolamine (DIPA). - triethanolamine (TEA). - n-methyldiethanolamine (MDEA) . 2- Caustic soda : -It’s sodium hydroxide (NaOH) : used to remove CO2 from air . Also it is used to react with the CO2 to produce the sodium carbonate. That will minimize the amount of carbon dioxide.
3- Hot potassium Carbonate: To improve CO2 absorption mass transfer and to inhibit corrosion. 4- Sodium Carbonate: Sodium carbonate was used as a sorbent to capture CO2 from a gaseous stream of carbon dioxide, nitrogen, and moisture. 5- Ammonia : NH3 has high efficiency to absorb CO2 that may reach 99% .
2. Physical Absorption: - Physical solvents remove CO2 from fuel gases with high vapor pressure. - The advantage of such solvents is that CO2 can be separated from them in the stripper by reducing the pressure resulting in much lower energy consumption . 1)- Flour process. 2)- Purisol process. 3)- Selexol process. 4)- Sulfinol processes. 5)- Rectisol . 3. Hybrid absorption : - Hybrid absorption processes use solvents which offer a combination of chemical and physical absorption processes. - used with coal for removal of CO2 and sulphur compounds .
Adsorption : - In the adsorption step, gas is fed to a bed of solids that adsorbs CO2 and allows the other gases to pass through. - When a bed becomes fully loaded with CO2, the feed gas is switched to another clean adsorption bed . - the fully loaded bed is regenerated to remove the CO2. 1)- Pressure swing adsorption : In (PSA), the adsorbent is regenerated by reducing pressure. it’s used to separate some gas species from a mixture of gases under pressure according to the species and adsorbent material. 2)- Temperature swing adsorption : In (TSA) the adsorbent is regenerated by raising its temperature . It removes CO2 from a gas stream is conducted using alumina to adsorb all the water and at least most of the carbon dioxide from the gas stream. 3)- Electric swing adsorption : In (ESA) regeneration takes place by passing a low-voltage electric current through the adsorbent.
3- Cryogenic: - Cryogenic separation is widely used commercially for purification of CO2 from streams that already have high CO2 concentrations. - It is not normally used for dilute CO2 streams such as flue gas from coal/natural gas fired boilers . - Advantage : 1)- that it enables direct production of liquid CO2 . 2)- It’s easy for storage and transport . - applications : It’s used for separation of CO2 from high pressure gases, such as in pre-combustion capture processes, in which the input gas contains a high concentration.
4. Membranes: A membrane is a barrier film that allows selective and specific permeation under conditions appropriate to its function. 1)- Gas separation membranes : Gas separation membranes rely on differences in physical or chemical interactions between gases and a membrane material, causing one component to pass through the membrane faster than another. - Types : ceramic, polymeric and a combination of two hybrid. 2)- Gas absorption membranes: Gas absorption membranes are micro-porous solid membranes that are used as contacting devices between gas flow and liquid flow. - Disadvantages : energy consumption and costs , and membranes have not been optimized for the large volume of gas separation .
Uses and utilization of Carbon Dioxide : Physical uses: - CO2 is used for quick freezing, surface freezing, chilling and refrigeration in the transport of foods. - It is used to remove caffeine from coffee . - It is used as a welding gas. - Solid carbon dioxide is used for small shipments and in fire extinguishers.
- Carbonated Soda : The basic idea is : injects the CO2 into the water it produced bubble to get the soda. To do this, need cold water, mix the syrup with water, connect up the CO2, and shake the 2 liter bottle as the pressurized CO2 enters the bottle. After a minute or so, you've got carbonated soda. - Oil recovery : CO2 is injected to the oil well , to increase the pressure then the oil will flow out .
Chemical uses : It is used in producing some chemical compounds, such as: - Methanol. - DME . - Styrene. - Propylene. - Acetic Acid. - Ethanol.
Ethyl alcohol: Ethanol (ethyl alcohol) and its chemical formula CH3CH2OH . - Physical properties: It is flammable, has a strong odor, volatile and a colorless and it is completely miscible with water and organic solvents . - Chemical Properties: 1. Combustion of Ethanol C2H5OH + 3O2 ==> 2CO2 + 3H2O 2. Dehydrogenation of Ethanol C2H5OH ==> CH3CHO + H2 Ethanol Ethanal 3. Ester formation RCOOH + HOCH2CH3 → RCOOCH2CH3 + H2O
Uses of Ethanol: Ethanol is used as a fuel and gasoline additive, in many medicines and drugs; as a disinfectant and used extensively as a solvent in the manufacture of varnishes and perfumes also used as the fluid in thermometers. Sources of Ethanol: - Corn . - sugar . - potato wastes . - cheese whey . - convert cellulose materials to ethanol . - Enzymes : are being researched that will convert cellulose to sugars which can then be fermented into ethanol .
Ethanol Production from CO2 Ethanol from CO2 Hydrogenation over K/Cu-Zn-Fe-Cr oxide catalyst. 2CO2 + 6H2 → C2H5OH + 3H2O heat of reaction ΔHº = -173 kJ/mol free energy changeΔGº = -65 kJ/mol