Biomass to Ethylene (B2) - Revision history

Jcl842: /* Economic Evaluation */

2015-03-16T17:17:08Z

Economic Evaluation

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	=Economic Evaluation=		=Economic Evaluation=

	After the process has been designed it is possible to conduct an economic analysis that will demonstrate whether the design can be profitable. To determine profitability of a long-term process it is important to estimate both initial plant capital costs as well as yearly variable costs associated with running the plant. To determine initial capital costs we sized and calculated price of units from correlations. Aspen Process Economic Analyzer aided with initial size and cost estimates. Installation costs were determined from correlations we found in literature (Towler, 2012). The major costs associated with the process derive from cost of feed materials (ICIS~~, 2015~~), which are summarized in Table 1.		After the process has been designed it is possible to conduct an economic analysis that will demonstrate whether the design can be profitable. To determine profitability of a long-term process it is important to estimate both initial plant capital costs as well as yearly variable costs associated with running the plant. To determine initial capital costs we sized and calculated price of units from correlations. Aspen Process Economic Analyzer aided with initial size and cost estimates. Installation costs were determined from correlations we found in literature (Towler, 2012). The major costs associated with the process derive from cost of feed materials (ICIS.com), which are summarized in Table 1.

	[[File:b2appendix8.png\|thumb\|border\|center\|middle\|upright=4\|link=\|atl=\|Table 1: Feed Costs]]		[[File:b2appendix8.png\|thumb\|border\|center\|middle\|upright=4\|link=\|atl=\|Table 1: Feed Costs]]

Jcl842: /* Ethanol to Ethylene Process */

2015-03-16T17:16:44Z

Ethanol to Ethylene Process

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	The ethanol entering section 400 must be pressurized to 40 bar and heated to 530 C prior to entering the reactor train. This increases reaction selectivity for our desired product, ethylene. Afterwards, the ethanol enters reactor R-400 to initiate the formation of ethylene. Each subsequent reactor increases the extent of reaction, which will increase ethylene and byproducts concentrations while lowering ethanol concentration in the outlet. The reactors calculate conversion of ethanol as a function of temperature. For our operating temperature and pressure, the conversions of each reaction are summarized in Appendix 6.		The ethanol entering section 400 must be pressurized to 40 bar and heated to 530 C prior to entering the reactor train. This increases reaction selectivity for our desired product, ethylene. Afterwards, the ethanol enters reactor R-400 to initiate the formation of ethylene. Each subsequent reactor increases the extent of reaction, which will increase ethylene and byproducts concentrations while lowering ethanol concentration in the outlet. The reactors calculate conversion of ethanol as a function of temperature. For our operating temperature and pressure, the conversions of each reaction are summarized in Appendix 6.

	The reaction is exothermic so the outlets of reactors R-400 and R-401, streams 403 and 405, must be heated back to optimal reaction temperature. As the outlet of this reaction train is at a very high temperature (400 0C) and pressure (62 bar), it must pass through a depressurizing valve and a cooler prior to entering the separation section. Once the stream (409) is at less extreme conditions (80 0C and 3.5 bar), it enters the separation section (500).		The reaction is exothermic so the outlets of reactors R-400 and R-401, streams 403 and 405, must be heated back to optimal reaction temperature. As the outlet of this reaction train is at a very high temperature (400 C) and pressure (62 bar), it must pass through a depressurizing valve and a cooler prior to entering the separation section. Once the stream (409) is at less extreme conditions (80 0C and 3.5 bar), it enters the separation section (500).

	Stream 409 leads into the first flash separator (S-500), which removes a bulk of the water that is formed in the reaction section. The wastewater (513) is sent for treatment at a different facility. Stream 500 contains our ethylene, along with several byproducts, water, and unreacted ethanol. The pressure of this stream must be lowered to 1 bar and cooled to 80 0C, prior to entering mixer M-500.		Stream 409 leads into the first flash separator (S-500), which removes a bulk of the water that is formed in the reaction section. The wastewater (513) is sent for treatment at a different facility. Stream 500 contains our ethylene, along with several byproducts, water, and unreacted ethanol. The pressure of this stream must be lowered to 1 bar and cooled to 80 C, prior to entering mixer M-500.

	Mixer M-500 mixes stream 502, 503, and 511 into stream 504, which enters our second flash separator. Stream 502 is simply our depressurized and cooled product stream, stream 503 is fresh tri-ethylene glycol (TEG), and stream 511 is recycled TEG. The TEG is useful in our process because it is miscible with water and in flash separations it causes a greater fraction of water to remain in the liquid phase. It allows separator S-501 to efficiently separate ethylene from stream 505 and purify it to a mole fraction of .992. The product is stored in tank T-501. The other outlet of S-501, stream 506, contains water, byproducts, and TEG. Stream 506 must be heated to 10 C prior to entering our last separation unit, S-502, which yields stream 510 (Recycle TEG), stream 512 (waste water), and stream 508 (byproducts). The wastewater (stream 512) is outsourced to a waste treatment facility while our byproducts stream (508) is burned and used as fuel. This concludes our process. Besides the polymer grade ethylene all other outlet streams are either burned or treated and released.		Mixer M-500 mixes stream 502, 503, and 511 into stream 504, which enters our second flash separator. Stream 502 is simply our depressurized and cooled product stream, stream 503 is fresh tri-ethylene glycol (TEG), and stream 511 is recycled TEG. The TEG is useful in our process because it is miscible with water and in flash separations it causes a greater fraction of water to remain in the liquid phase. It allows separator S-501 to efficiently separate ethylene from stream 505 and purify it to a mole fraction of .992. The product is stored in tank T-501. The other outlet of S-501, stream 506, contains water, byproducts, and TEG. Stream 506 must be heated to 10 C prior to entering our last separation unit, S-502, which yields stream 510 (Recycle TEG), stream 512 (waste water), and stream 508 (byproducts). The wastewater (stream 512) is outsourced to a waste treatment facility while our byproducts stream (508) is burned and used as fuel. This concludes our process. Besides the polymer grade ethylene all other outlet streams are either burned or treated and released.

Jcl842: /* Design Approach */

2015-03-16T17:16:06Z

Design Approach

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	Before settling upon a final design, we searched potential plant locations where we would have a consistent source of biomass. Additionally, we hoped to leverage the environmentally friendly aspects of our process to receive tax credits for our plant investment and ethylene production.		Before settling upon a final design, we searched potential plant locations where we would have a consistent source of biomass. Additionally, we hoped to leverage the environmentally friendly aspects of our process to receive tax credits for our plant investment and ethylene production.
	We decided upon Iowa for our plant location as the state produces substantial source of corn stover from their farms (Iowa Corn Growers Association), and the local governments use tax credits to encourage production with renewable resources (FAS.org). We chose to build our plant in Sioux City as the property tax in surrounding county is $13/$1000 of property value (~~Property Tax, 2011~~), which is one of the lowest in the area.		We decided upon Iowa for our plant location as the state produces substantial source of corn stover from their farms (Iowa Corn Growers Association), and the local governments use tax credits to encourage production with renewable resources (FAS.org). We chose to build our plant in Sioux City as the property tax in surrounding county is $13/$1000 of property value (iowataxrate.com), which is one of the lowest in the area.

	=Process Overview=		=Process Overview=

Jcl842: /* Design Approach */

2015-03-16T17:15:47Z

Design Approach

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	Before settling upon a final design, we searched potential plant locations where we would have a consistent source of biomass. Additionally, we hoped to leverage the environmentally friendly aspects of our process to receive tax credits for our plant investment and ethylene production.		Before settling upon a final design, we searched potential plant locations where we would have a consistent source of biomass. Additionally, we hoped to leverage the environmentally friendly aspects of our process to receive tax credits for our plant investment and ethylene production.
	We decided upon Iowa for our plant location as the state produces substantial source of corn stover from their farms (Iowa Corn Growers Association), and the local governments use tax credits to encourage production with renewable resources (~~Service, 2011)~~). We chose to build our plant in Sioux City as the property tax in surrounding county is $13/$1000 of property value (Property Tax, 2011), which is one of the lowest in the area.		We decided upon Iowa for our plant location as the state produces substantial source of corn stover from their farms (Iowa Corn Growers Association), and the local governments use tax credits to encourage production with renewable resources (FAS.org). We chose to build our plant in Sioux City as the property tax in surrounding county is $13/$1000 of property value (Property Tax, 2011), which is one of the lowest in the area.

	=Process Overview=		=Process Overview=

Jcl842: /* Design Approach */

2015-03-16T17:14:56Z

Design Approach

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	As mentioned above, our primary goal is to create a process that is sustainable and also highly efficient. Before researching comparable processes in industry, we defined a set of characteristics which believed would value both environmental and economic considerations. We focused on processes with low utility usage, low production of toxic waste, and avoidance of extreme temperatures and pressures.		As mentioned above, our primary goal is to create a process that is sustainable and also highly efficient. Before researching comparable processes in industry, we defined a set of characteristics which believed would value both environmental and economic considerations. We focused on processes with low utility usage, low production of toxic waste, and avoidance of extreme temperatures and pressures.

	Our initial investigation centered on a review of literature on similar processes. Though the production of ethylene from biomass is currently uncommon, there are many industrial processes that capture different parts of our process. Currently in industry we found many examples of plants which convert biomass to ethanol (Humbird, 2011 & Kazi, 2011). Though somewhat less common, we were also able to find several examples of plants which produce ethylene with ethanol as a starting feed (Tsao 1979, Cameron 2012, Intratec Solutions 2013). Through separate analysis of each of these processes, we hoped to combine the designs into a single plant.		Our initial investigation centered on a review of literature on similar processes. Though the production of ethylene from biomass is currently uncommon, there are many industrial processes that capture different parts of our process. Currently in industry we found many examples of plants which convert biomass to ethanol (Humbird, 2011; Kazi, 2011). Though somewhat less common, we were also able to find several examples of plants which produce ethylene with ethanol as a starting feed (Tsao 1979; Cameron 2012; Intratec Solutions 2013). Through separate analysis of each of these processes, we hoped to combine the designs into a single plant.

	Before settling upon a final design, we searched potential plant locations where we would have a consistent source of biomass. Additionally, we hoped to leverage the environmentally friendly aspects of our process to receive tax credits for our plant investment and ethylene production.		Before settling upon a final design, we searched potential plant locations where we would have a consistent source of biomass. Additionally, we hoped to leverage the environmentally friendly aspects of our process to receive tax credits for our plant investment and ethylene production.

Jcl842: /* Background */

2015-03-16T17:14:25Z

Background

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	Initially, the design of this process began with the Technology Division of Evanston Chemical requesting a preliminary design and cost estimation of a manufacturing facility producing ethylene. Of the potential production routes available, we selected to investigate a plant that produces ethylene from a starting feed of biomass. The biomass will be converted to ethanol via fermentation, which is then converted to ethylene via catalysis. We selected this route because of our interest in a sustainable and efficient production of ethylene.		Initially, the design of this process began with the Technology Division of Evanston Chemical requesting a preliminary design and cost estimation of a manufacturing facility producing ethylene. Of the potential production routes available, we selected to investigate a plant that produces ethylene from a starting feed of biomass. The biomass will be converted to ethanol via fermentation, which is then converted to ethylene via catalysis. We selected this route because of our interest in a sustainable and efficient production of ethylene.

	Each year, over 100 million metric tons of ethylene are produced through various processes (Wikipedia~~, 2015~~); this represents the largest annual production of any organic compound. Ethylene is a very common starting material in industrial processes as it is used in the creation of many polymers. Currently, most commercially available ethylene is produced through steam cracking with petroleum as a starting ingredient (Humbird, 2011). This is problematic in the long term: world petroleum resources are limited and ethylene demand will only increase as the use of polymers in industry becomes more common. We seek to design a renewable process that utilizes a corn stover feed, a cheap and easily accessible byproduct of growing corn. As fossil fuels become scarcer, we expect the value of such a process to increase over time, and we see substantial value in developing an industry leading biomass to ethylene production plant.		Each year, over 100 million metric tons of ethylene are produced through various processes (Wikipedia.com); this represents the largest annual production of any organic compound. Ethylene is a very common starting material in industrial processes as it is used in the creation of many polymers. Currently, most commercially available ethylene is produced through steam cracking with petroleum as a starting ingredient (Humbird, 2011). This is problematic in the long term: world petroleum resources are limited and ethylene demand will only increase as the use of polymers in industry becomes more common. We seek to design a renewable process that utilizes a corn stover feed, a cheap and easily accessible byproduct of growing corn. As fossil fuels become scarcer, we expect the value of such a process to increase over time, and we see substantial value in developing an industry leading biomass to ethylene production plant.

	=Design Approach=		=Design Approach=

Jcl842: /* References */

2015-03-16T17:13:55Z

References

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	Kazi, F., Fortman, J., et al. Techno-Economic Analysis of Biochemical Scenarios for Production of Cellulosic Ethanol. Published 2011. Available at: <http://www.nrel.gov/docs/fy10osti/46588.pdf>. Accessed 13 March 2015.		Kazi, F., Fortman, J., et al. Techno-Economic Analysis of Biochemical Scenarios for Production of Cellulosic Ethanol. Published 2011. Available at: <http://www.nrel.gov/docs/fy10osti/46588.pdf>. Accessed 13 March 2015.

	ICIS. ~~“Indicative~~ Chemical Prices A-Z”. Available at: <http://www.icis.com/chemicals/channel-infochemicals-a-z/>~~. Accessed 13 March 2015~~.		ICIS.com. Indicative Chemical Prices A-Z [Internet]. c2015 [cited 13 March 2015] Available at: <http://www.icis.com/chemicals/channel-infochemicals-a-z/>.

	Intratec Solutions, LLC. Green Ethylene from Ethanol via Dehydration. Published, 2013. Available at <http://base.intratec.us/home/chemical-processes/ethylene/green-ethylene-from-ethanol-via-dehydration-research-economics>. Accessed 13 March 2015		Intratec Solutions, LLC. Green Ethylene from Ethanol via Dehydration. Published, 2013. Available at <http://base.intratec.us/home/chemical-processes/ethylene/green-ethylene-from-ethanol-via-dehydration-research-economics>. Accessed 13 March 2015

	Iowa Corn Growers Association. “Infographics”. Available at < http://www.iowacorn.org/en/corn_use_education/infographics/>~~. Accessed 13 March 2015.~~		Iowacorn.org [Internet]. Iowa Corn Growers Association. “Infographics”. c2015d [Cited 13 March 2015]. Available at < http://www.iowacorn.org/en/corn_use_education/infographics/>

	Property Tax. N.p., n.d. "Plymouth County." Published 30 Jan. 2015. <http://www.lowtaxrate.com/iowa/plymouth-county>~~. Accessed 13 March 2015~~.		Iowataxrate.com [Internet]. Property Tax. N.p., n.d. Plymouth County. Published Web 30 Jan. 2015 [Cited 13 March 2015]. <http://www.lowtaxrate.com/iowa/plymouth-county>.

	Congressional Research Service. Biofuels Incentives: A Summary of Federal Programs (n.d.): ~~FAS.org.~~ Published 11 Jan. 2013. Electronically Published 25 Jan. 2015.		FAS.org [Internet]. Congressional Research Service. Biofuels Incentives: A Summary of Federal Programs (n.d.): Published 11 Jan. 2013. Electronically Published 25 Jan. 2015 [Cited 13 March 2015]

	The Essential Chemistry Online. “Ethene (Ethylene)”. Available at <http://www.essentialchemicalindustry.org/chemicals/ethene.html>~~. Accessed 13 March 2015~~.		EssentialChemicalIndustry.org [Internet[. The Essential Chemistry Online. “Ethene (Ethylene)”. c2015d [Cited 13 March 2014] Available at <http://www.essentialchemicalindustry.org/chemicals/ethene.html>.

	Towler G, Sinnott R. Chemical Engineering Design: Principles, Practice and Economics of Plant and Process Design. 2nd ed. Boston: Elsevier; 2013.		Towler G, Sinnott R. Chemical Engineering Design: Principles, Practice and Economics of Plant and Process Design. 2nd ed. Boston: Elsevier; 2013.

	Tsao, U. & Zasloff, R. Production of Ethylene from Ethanol~~, 1979~~. Patent No. 4,134,926		Tsao, U. & Zasloff, R., inventors; The Lummus Company, assignee. Production of Ethylene from Ethanol. United States Patent No. 4,134,926. 1979 Jan 16.

	U.S. Energy Information Association. State Energy Profiles. Available at: <http://www.eia.gov/electricity/state>~~. Accessed 13 March 2015~~.		EIA.gov [Internet]. U.S. Energy Information Association. State Energy Profiles. c2015 [Cited 13 March 2015]. Available at: <http://www.eia.gov/electricity/state>.

	Wikipedia. ~~“Ethylene”~~. Available at <http://en.wikipedia.org/wiki/Ethylene>~~. Accessed 13 March 2015~~.		Wikipedia.com [Internet]. Ethylene. c2015 [Cited 13 March 2015] Available at <http://en.wikipedia.org/wiki/Ethylene>.

	=Appendices=		=Appendices=

Jcl842: /* Background */

2015-03-16T17:04:44Z

Background

← Older revision		Revision as of 12:04, 16 March 2015
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	Initially, the design of this process began with the Technology Division of Evanston Chemical requesting a preliminary design and cost estimation of a manufacturing facility producing ethylene. Of the potential production routes available, we selected to investigate a plant that produces ethylene from a starting feed of biomass. The biomass will be converted to ethanol via fermentation, which is then converted to ethylene via catalysis. We selected this route because of our interest in a sustainable and efficient production of ethylene.		Initially, the design of this process began with the Technology Division of Evanston Chemical requesting a preliminary design and cost estimation of a manufacturing facility producing ethylene. Of the potential production routes available, we selected to investigate a plant that produces ethylene from a starting feed of biomass. The biomass will be converted to ethanol via fermentation, which is then converted to ethylene via catalysis. We selected this route because of our interest in a sustainable and efficient production of ethylene.

	Each year, over 100 million metric tons of ethylene are produced through various processes (Wikipedia, 2015); this represents the largest annual production of any organic compound. Ethylene is a very common starting material in industrial processes as it is used in the creation of many polymers. Currently, most commercially available ethylene is produced through steam cracking with petroleum as a starting ~~ingredient2~~. This is problematic in the long term: world petroleum resources are limited and ethylene demand will only increase as the use of polymers in industry becomes more common. We seek to design a renewable process that utilizes a corn stover feed, a cheap and easily accessible byproduct of growing corn. As fossil fuels become scarcer, we expect the value of such a process to increase over time, and we see substantial value in developing an industry leading biomass to ethylene production plant.		Each year, over 100 million metric tons of ethylene are produced through various processes (Wikipedia, 2015); this represents the largest annual production of any organic compound. Ethylene is a very common starting material in industrial processes as it is used in the creation of many polymers. Currently, most commercially available ethylene is produced through steam cracking with petroleum as a starting ingredient (Humbird, 2011). This is problematic in the long term: world petroleum resources are limited and ethylene demand will only increase as the use of polymers in industry becomes more common. We seek to design a renewable process that utilizes a corn stover feed, a cheap and easily accessible byproduct of growing corn. As fossil fuels become scarcer, we expect the value of such a process to increase over time, and we see substantial value in developing an industry leading biomass to ethylene production plant.

	=Design Approach=		=Design Approach=

Jcl842: /* References */

2015-03-16T00:32:55Z

References

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	Cameron, G., Le, L. Process Design for the Production of Ethylene from Ethanol. Published 2012. Available at: <http://repository.upenn.edu/cgi/viewcontent.cgi?article=1036&context=cbe_sdr>. Accessed 13 March 2015		Cameron, G., Le, L. Process Design for the Production of Ethylene from Ethanol. Published 2012. Available at: <http://repository.upenn.edu/cgi/viewcontent.cgi?article=1036&context=cbe_sdr>. Accessed 13 March 2015

	Humbird, D., Davis, R., Tao, L., Kinchin, C., Hsu, D., Aden, A., Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover. Published 2011. Available at: <http://www.nrel.gov/docs/fy11osti/47764.pdf>. Accessed 13 March 2015.		Humbird, D., Davis, R., Tao, L., Kinchin, C., Hsu, D., Aden, A. Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover. Published 2011. Available at: <http://www.nrel.gov/docs/fy11osti/47764.pdf>. Accessed 13 March 2015.

	Kazi, F., Fortman, J., et al. Techno-Economic Analysis of Biochemical Scenarios for Production of Cellulosic Ethanol. Published 2011. Available at: <http://www.nrel.gov/docs/fy10osti/46588.pdf>. Accessed 13 March 2015.		Kazi, F., Fortman, J., et al. Techno-Economic Analysis of Biochemical Scenarios for Production of Cellulosic Ethanol. Published 2011. Available at: <http://www.nrel.gov/docs/fy10osti/46588.pdf>. Accessed 13 March 2015.
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	Iowa Corn Growers Association. “Infographics”. Available at < http://www.iowacorn.org/en/corn_use_education/infographics/>. Accessed 13 March 2015.		Iowa Corn Growers Association. “Infographics”. Available at < http://www.iowacorn.org/en/corn_use_education/infographics/>. Accessed 13 March 2015.

	Property Tax. N.p., n.d. "Plymouth County." ~~Web.~~ 30 Jan. 2015. <http://www.lowtaxrate.com/iowa/plymouth-county>. Accessed 13 March 2015.		Property Tax. N.p., n.d. "Plymouth County." Published 30 Jan. 2015. <http://www.lowtaxrate.com/iowa/plymouth-county>. Accessed 13 March 2015.

	Congressional Research Service. Biofuels Incentives: A Summary of Federal Programs (n.d.): FAS.org. 11 Jan. 2013. ~~Web.~~ 25 Jan. 2015.		Congressional Research Service. Biofuels Incentives: A Summary of Federal Programs (n.d.): FAS.org. Published 11 Jan. 2013. Electronically Published 25 Jan. 2015.

	The Essential Chemistry Online. “Ethene (Ethylene)”. Available at <http://www.essentialchemicalindustry.org/chemicals/ethene.html>. Accessed 13 March 2015.		The Essential Chemistry Online. “Ethene (Ethylene)”. Available at <http://www.essentialchemicalindustry.org/chemicals/ethene.html>. Accessed 13 March 2015.

Jcl842: /* References */

2015-03-16T00:30:08Z

References

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	=References=		=References=

	Cameron, G., Le, L~~., et al~~. Process Design for the Production of Ethylene from Ethanol; 2012. Available at: <http://repository.upenn.edu/cgi/viewcontent.cgi?article=1036&context=cbe_sdr>. Accessed 13 March 2015		Cameron, G., Le, L. Process Design for the Production of Ethylene from Ethanol. Published 2012. Available at: <http://repository.upenn.edu/cgi/viewcontent.cgi?article=1036&context=cbe_sdr>. Accessed 13 March 2015

	Humbird, D. et al. Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover; 2011. Available at: <http://www.nrel.gov/docs/fy11osti/47764.pdf>. Accessed 13 March 2015.		Humbird, D., Davis, R., Tao, L., Kinchin, C., Hsu, D., Aden, A., Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover. Published 2011. Available at: <http://www.nrel.gov/docs/fy11osti/47764.pdf>. Accessed 13 March 2015.

	Kazi, F., Fortman, J., et al. Techno-Economic Analysis of Biochemical Scenarios for Production of Cellulosic Ethanol; 2011. Available at: <http://www.nrel.gov/docs/fy10osti/46588.pdf>. Accessed 13 March 2015.		Kazi, F., Fortman, J., et al. Techno-Economic Analysis of Biochemical Scenarios for Production of Cellulosic Ethanol. Published 2011. Available at: <http://www.nrel.gov/docs/fy10osti/46588.pdf>. Accessed 13 March 2015.

	ICIS. “Indicative Chemical Prices A-Z”. Available at: <http://www.icis.com/chemicals/channel-infochemicals-a-z/>. Accessed 13 March 2015.		ICIS. “Indicative Chemical Prices A-Z”. Available at: <http://www.icis.com/chemicals/channel-infochemicals-a-z/>. Accessed 13 March 2015.