Bio-propane from glycerol for biogas addition
(2008)- Abstract
- In this report, the technical and economical feasibility to produce higher alkanes from bio-glycerol has been investigated. The main purpose of producing this kind of chemicals would be to replace the fossil LPG used in upgraded biogas production. When producing biogas and exporting it to the natural gas grid, the Wobbe index and heating value does not match the existing natural gas. Therefore, the upgraded biogas that is put into the natural gas grid in Sweden today contains 8-10 vol-% of LPG.
The experimental work performed in association to this report has shown that it is possible to produce propane from glycerol. However, the production of ethane from glycerol may be even more advantageous. The experimental work has included... (More) - In this report, the technical and economical feasibility to produce higher alkanes from bio-glycerol has been investigated. The main purpose of producing this kind of chemicals would be to replace the fossil LPG used in upgraded biogas production. When producing biogas and exporting it to the natural gas grid, the Wobbe index and heating value does not match the existing natural gas. Therefore, the upgraded biogas that is put into the natural gas grid in Sweden today contains 8-10 vol-% of LPG.
The experimental work performed in association to this report has shown that it is possible to produce propane from glycerol. However, the production of ethane from glycerol may be even more advantageous. The experimental work has included developing and testing catalysts for several intermediate reactions. The work was performed using different micro-scale reactors with a liquid feed rate of 18 g/h.
The first reaction, independent on if propane or ethane is to be produced, is dehydration of glycerol to acrolein. This was showed during 60 h on an acidic catalyst with a yield of 90%. The production of propanol, the second intermediate to producing propane, was shown as well. Propanol was produced both using acrolein as the starting material as well as glycerol (combining the first and second step) with yields of 70-80% in the first case and 65-70% in the second case. The propanol produced was investigated for its dehydration to propene, with a yield of 70-75%. By using a proprietary, purposely developed catalyst the propene was hydrogenated to propane, with a yield of 85% from propanol. The formation of propane from glycerol was finally investigated, with an overall yield of 55%.
The second part of the experimental work performed investigated the possibilities of decarbonylating acrolein to form ethane. This was made possible by the development of a proprietary catalyst which combines decarbonylation and water-gas shift functionality. By combining these two functionalities, no hydrogen have to be externally produced which is the case of the propane produced. The production of ethane from acrolein was shown with a yield of 75%, while starting from glycerol yielded 65-70% ethane using the purposely developed catalyst. However, in light of this there are still work to be performed with optimizing catalyst compositions and process conditions to further improve the process yield.
The economic feasibility and the glycerol supply side of the proposed process have been investigated as well within the scope of the report. After an initial overview of the glycerol supply, it is apparent that at least the addition of alkanes to biogas can be saturated by glycerol for the Swedish market situation at the moment and for a foreseeable future. The current domestic glycerol production would sustain the upgraded biogas industry for quite some time, if necessary. However, from a cost standpoint a lower grade glycerol should perhaps be considered.
In the cost aspect, three different configurations have been compared. The three alternatives are ethane production, propane production with internal hydrogen supply and propane production with external hydrogen supply. The results from the base case calculations can be viewed in table ES1.
The base case calculations are based on carburating the upgraded biogas, before introducing it to the natural gas grid, from a 24 GWh biogas production facility. This means that the production units supply an acceptable Wobbe index of the final upgraded biogas. The annual cost in table ES1 is the yearly cost of carburating the gas at a 24 GWh biogas site. From the base case, it is obvious that there are differences in glycerol consumption depending on what alternative is chosen. There are also investment cost differences. To further investigate the volatility of the prices, a blend of Monte Carlo techniques were used to generate multiple data sets.
The conclusions from the simulations were that the ethane producing facility has a stronger dependence on the feedstock; it is hence more sensitive to changes in the feedstock cost. It is however not as sensitive to changes in investment cost. If the production cost is compared to the cost of fossil LPG used today, the cost of the LPG is 0.43 kr/kWh. This does however not include the taxation and transporting the fuel. Adding the taxation alone will put an additional 0.25 kr/kWh on the cost, totalling 0.68 kr/kWh. This compares well with the calculated production cost of 0.78 kr/kWh for ethane and with the 50% percentile acquired from the Monte Carlo simulations of 0.94 kr/kWh. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1270944
- author
- Brandin, Jan LU ; Hulteberg, Christian LU and Liljegren Nilsson, Andreas
- organization
- publishing date
- 2008
- type
- Book/Report
- publication status
- published
- subject
- keywords
- bio-SNG, Wobbe-index, SNG, bio-ethene, bio-ethane, bio-propene, bio-propane, catalytic process, catalytic conversion, catalyst, glycerol, glycerine, biodiesel, biofuel, transestrification
- pages
- 24 pages
- publisher
- Svenskt Gastekniskt Center AB
- report number
- Rapport SGC 198
- external identifiers
-
- other:ISRN SGC-R198-SE
- language
- English
- LU publication?
- yes
- id
- 6cc4be37-5782-45e9-9f83-3eda8dabab62 (old id 1270944)
- alternative location
- http://www.sgc.se/dokument/SGC198.pdf
- date added to LUP
- 2016-04-04 12:25:41
- date last changed
- 2018-11-21 21:10:53
@techreport{6cc4be37-5782-45e9-9f83-3eda8dabab62, abstract = {{In this report, the technical and economical feasibility to produce higher alkanes from bio-glycerol has been investigated. The main purpose of producing this kind of chemicals would be to replace the fossil LPG used in upgraded biogas production. When producing biogas and exporting it to the natural gas grid, the Wobbe index and heating value does not match the existing natural gas. Therefore, the upgraded biogas that is put into the natural gas grid in Sweden today contains 8-10 vol-% of LPG. <br/><br> The experimental work performed in association to this report has shown that it is possible to produce propane from glycerol. However, the production of ethane from glycerol may be even more advantageous. The experimental work has included developing and testing catalysts for several intermediate reactions. The work was performed using different micro-scale reactors with a liquid feed rate of 18 g/h. <br/><br> The first reaction, independent on if propane or ethane is to be produced, is dehydration of glycerol to acrolein. This was showed during 60 h on an acidic catalyst with a yield of 90%. The production of propanol, the second intermediate to producing propane, was shown as well. Propanol was produced both using acrolein as the starting material as well as glycerol (combining the first and second step) with yields of 70-80% in the first case and 65-70% in the second case. The propanol produced was investigated for its dehydration to propene, with a yield of 70-75%. By using a proprietary, purposely developed catalyst the propene was hydrogenated to propane, with a yield of 85% from propanol. The formation of propane from glycerol was finally investigated, with an overall yield of 55%.<br/><br> The second part of the experimental work performed investigated the possibilities of decarbonylating acrolein to form ethane. This was made possible by the development of a proprietary catalyst which combines decarbonylation and water-gas shift functionality. By combining these two functionalities, no hydrogen have to be externally produced which is the case of the propane produced. The production of ethane from acrolein was shown with a yield of 75%, while starting from glycerol yielded 65-70% ethane using the purposely developed catalyst. However, in light of this there are still work to be performed with optimizing catalyst compositions and process conditions to further improve the process yield. <br/><br> The economic feasibility and the glycerol supply side of the proposed process have been investigated as well within the scope of the report. After an initial overview of the glycerol supply, it is apparent that at least the addition of alkanes to biogas can be saturated by glycerol for the Swedish market situation at the moment and for a foreseeable future. The current domestic glycerol production would sustain the upgraded biogas industry for quite some time, if necessary. However, from a cost standpoint a lower grade glycerol should perhaps be considered. <br/><br> In the cost aspect, three different configurations have been compared. The three alternatives are ethane production, propane production with internal hydrogen supply and propane production with external hydrogen supply. The results from the base case calculations can be viewed in table ES1.<br/><br> The base case calculations are based on carburating the upgraded biogas, before introducing it to the natural gas grid, from a 24 GWh biogas production facility. This means that the production units supply an acceptable Wobbe index of the final upgraded biogas. The annual cost in table ES1 is the yearly cost of carburating the gas at a 24 GWh biogas site. From the base case, it is obvious that there are differences in glycerol consumption depending on what alternative is chosen. There are also investment cost differences. To further investigate the volatility of the prices, a blend of Monte Carlo techniques were used to generate multiple data sets. <br/><br> The conclusions from the simulations were that the ethane producing facility has a stronger dependence on the feedstock; it is hence more sensitive to changes in the feedstock cost. It is however not as sensitive to changes in investment cost. If the production cost is compared to the cost of fossil LPG used today, the cost of the LPG is 0.43 kr/kWh. This does however not include the taxation and transporting the fuel. Adding the taxation alone will put an additional 0.25 kr/kWh on the cost, totalling 0.68 kr/kWh. This compares well with the calculated production cost of 0.78 kr/kWh for ethane and with the 50% percentile acquired from the Monte Carlo simulations of 0.94 kr/kWh.}}, author = {{Brandin, Jan and Hulteberg, Christian and Liljegren Nilsson, Andreas}}, institution = {{Svenskt Gastekniskt Center AB}}, keywords = {{bio-SNG; Wobbe-index; SNG; bio-ethene; bio-ethane; bio-propene; bio-propane; catalytic process; catalytic conversion; catalyst; glycerol; glycerine; biodiesel; biofuel; transestrification}}, language = {{eng}}, number = {{Rapport SGC 198}}, title = {{Bio-propane from glycerol for biogas addition}}, url = {{http://www.sgc.se/dokument/SGC198.pdf}}, year = {{2008}}, }