cbe 250 process design report

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Memorandum Date: December 14, 2015 To: Business Development Department From: Keshena Koran, Paul Meyers, Ricardo Ruiz, Luis Velazquez, Chemical Engineering Consultants Subject: Process for succinic acid production Process Summary The process will supply the eight fermenters with a batch of approximately 710800 L glucose-water solution and an engineered strain of E. coli to ferment the solution. This will be done in 40-hour batches at 40° C using a constantly recycled stream of CO 2 bubbled through the fermenters. After the fermentation process is done, the batch extract will be sent through a separation process to obtain a sufficiently pure product of succinic acid crystals. The first separator is a simple mechanical filtration system to pull out the small concentration of insoluble matter in the stream. The exiting liquid stream from the first separator is then temporarily stored in a holding tank to cool the solution down to about 25° C. This stream is then sent to a liquid-liquid extractor that uses 1-octanol as the solvent to form two immiscible layers in which a large percentage of the acid subproducts are extracted in the organic phase. This process is done at 25° C to improve the separation factor of the succinic acid and subproducts [1]. The aqueous phase is then sent to a chiller to be cooled for crystallization. The crystallizer finally purifies a 99% succinic acid stream and a glucose-water stream to be reused. The versatility and applicability of Succinic acid encompasses a wide array of industries. Particularly, succinic acid can be used as a replacement for various petrochemical “building blocks”. Some examples of intermediates that can be synthesized from this four-carbon dicarboxylic acid are tetrahydrofuran (THF), γ-butyrolactone, 1,4- butanediol, adipic acid, N-methyl pyrrolidinone, and 2-pyrrolidinone [2]. In particular, THF, a monomer and a solvent, is the major component of the synthetic fiber Spandex® and other biodegradable

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Page 1: CBE 250 Process Design Report

MemorandumDate: December 14, 2015To: Business Development DepartmentFrom: Keshena Koran, Paul Meyers, Ricardo Ruiz, Luis Velazquez, Chemical Engineering ConsultantsSubject: Process for succinic acid production

Process Summary

The process will supply the eight fermenters with a batch of approximately 710800 L glucose-water solution and an engineered strain of E. coli to ferment the solution. This will be done in 40-hour batches at 40° C using a constantly recycled stream of CO2 bubbled through the fermenters. After the fermentation process is done, the batch extract will be sent through a separation process to obtain a sufficiently pure product of succinic acid crystals. The first separator is a simple mechanical filtration system to pull out the small concentration of insoluble matter in the stream. The exiting liquid stream from the first separator is then temporarily stored in a holding tank to cool the solution down to about 25° C. This stream is then sent to a liquid-liquid extractor that uses 1-octanol as the solvent to form two immiscible layers in which a large percentage of the acid subproducts are extracted in the organic phase. This process is done at 25° C to improve the separation factor of the succinic acid and subproducts [1]. The aqueous phase is then sent to a chiller to be cooled for crystallization. The crystallizer finally purifies a 99% succinic acid stream and a glucose-water stream to be reused.

The versatility and applicability of Succinic acid encompasses a wide array of industries. Particularly, succinic acid can be used as a replacement for various petrochemical “building blocks”. Some examples of intermediates that can be synthesized from this four-carbon dicarboxylic acid are tetrahydrofuran (THF), γ-butyrolactone, 1,4-butanediol, adipic acid, N-methyl pyrrolidinone, and 2-pyrrolidinone [2]. In particular, THF, a monomer and a solvent, is the major component of the synthetic fiber Spandex® and other biodegradable polyester fibers used in the textile industry [2]. Other notable products are polymers such as polybutyrate succinate (PBS), polyamides (Nylon®), and polybutylene teraphthalate (PBT). In short, succinic acid derivatives can be found in the food, electronics, and even the automotive industry.

Furthermore, the fermentation byproducts during the extraction stage are maleic acid, acetic acid, pyruvic acid, and fumaric acid. Both maleic and fumaric acid have known reaction pathways that can effectively synthesize more succinic acid via a reaction with either a titanium cathode or by recombinant E. coli [3,4]. Thus, finding a profitable market, or a practical use of maleic acid and fumaric acid is certainly an attainable goal. How efficient this goal is relies exclusively on the type of separation technology required to crash out the acetic acid and pyruvic acid from the solution. Fortunately, there is a clear difference in the boiling points of maleic acid, fumaric acid and 1-octanol which can be exploited to conduct a separation via distillation. Density differences can also be exploited by centrifusion with fumaric acid and maleic acid both having a density that is approximately twice the density of 1-octanol.

Page 2: CBE 250 Process Design Report

Process Economy

Given the following design, the process is expected to net approximately $166400 per year. This is calculated simply using the prices of 1,4-butanediol, glucose, and the yield between them. Importantly, this does not include the cost of 1-octanol (as it is reused), energy, nor machine maintenance as it could greatly vary. Instead, this is used as a preliminary calculation to prove the viability of a profitable process based on the value of the inputs and products. It is also worth noting that by adding unlisted separator(s) to further purify the recycled glucose-water stream would significantly increase the yield of succinic acid, and hence, that of 1,4-butanediol. Assuming all succinic acid is recovered, the process can yield a maximum profit of $405800 per year. Again, it is important to consider the cost of each process unit including the additional unlisted separators if using the latter figure for determining profits.

Page 3: CBE 250 Process Design Report

Equations

W: waterG: glucoseA: succinic acidS: subproductsI: insolublesO: 1-octanol

Stream Flow:

mA,8 = 2475 kg/batch

Stream Composition:

mS,1 / (mW,1 + mG,1 + mA,1 + mS,1 + mI,1) = .00249mI,1 / (mW,1 + mG,1 + mA,1 + mS,1 + mI,1) = .00002

mA,4 / mO,4 = .00158

mG,6 / (mW,6 + mG,6 + mA,6 + mS,6) = .00799mA,6 / (mW,6 + mG,6 + mA,6 + mS,6) = .00499

mA,8 / (mW,8 + mG,8 + mA,8 + mS,8) = .99

System Performance:

mA,5 = .02mA,6

mS,5 = .99mS,3

mA,8 = .7mA,6 [5]mG,7 / mW,7 = mG,8 / mW,8

mS,7 / mW,7 = mS,8 / mW,8

Page 4: CBE 250 Process Design Report

Material Balance:

mW,F = mW,1

mG,F = mG,1 + EE = 1.017mA,1

mW,1 = mW,3

mG,1 = mG,3

mA,1 = mA,3

mS,1 = mS,3

mI,1 = mI,2

mW,3 = mW,6

mG,3 = mG,6

mA,3 = mA,5 + mA,6

mS,3 = mS,5 + mS,6

mO,4 = mO,5

mW,6 = mW,7 + mW,8

mG,6 = mG,7 + mG,8

mA,6 = mA,7 + mA,8

mS,6 = mS,7 + mS,8

Table of Flows in kg/batch

i mi,F mi,1 mi,2 mi,3 mi,4 mi,5 mi,6 mi,7 mi,8

W 699345 699345 0 699345 0 0 699345 699320 24.8

G 9328 5661 0 5661 0 0 5661 5661 .2008

A 0 3606 0 3606 0 70.71 3536 1061 2475

S 0 1769 0 1769 0 1751 17.69 17.69 .000627

I 0 14.21 14.21 0 0 0 0 0 0

O 0 0 0 0 44782 44782 0 0 0

Page 5: CBE 250 Process Design Report

Appendix

Stream flow calculation:

500,000 kg/year succinic acid / 8000 hr/year * 40 hr/batch * .99 (purity) =2475 kg/batch succinic acid

Stream composition calculations:

Stream six:fractional volume of glucose: 8 g/L / 1540 g/L= .00519fractional volume of succinic acid: 5 g/L / 1560 g/L = .00321fractional volume of subproducts: <.03 g/L / (average density) = negligiblefractional volume of water: 1 - .00519 - .00321 = .99160concentration of water: .99160 * 997 g/L = 988.6 g/Ldensity of solution: 988.6 g/L + 8 g/L + 5 g/L = 1001.6 g/Lmass fraction of glucose: 8 g/L / 1001.6 g/L = .00799mass fraction of succinic acid: 5 g/L / 1001.6 g/L = .00499

Stream one:change in density negligible between liquid extraction phaseconcentration of subproducts: .36 g/L + .40 g/L + 1.57 g/L + .16 g/L = 2.49 g/Lmass fraction of subproducts: 2.49 g/L / 1001.6 g/L = .00249mass fraction of insolubles: .02 g/L / 1001.6 g/L = .00002

Stream four:5 g succinic acid/L aqueous solution * .26 (g succinic acid/ L 1-octanol solution)/(g succinic acid/L aqueous solution) = 1.3 g succinic acid/L 1-octanol solution [6]fractional volume of succinic acid: 1.3 g/L / 1560 g/L = .00083fractional volume of 1-octanol: 1 - .00083 = .99917concentration of 1-octanol: .99917 * 824 g/L = 823.3 g/Lmass ratio of succinic acid to 1-octanol: 1.3 g/L / 823.3 g/L = .00158

(note: this is an estimate for the 1-octanol flow as this uses the cited partition coefficient that was obtained without other chemicals in solution. More experimental data targeted for this specific scenario would be necessary to find more exact values.)

Extent of reaction calculation:

180.16 g/gmol glucose / 1.5 gmol succinic acid/gmol glucose / 118.09 g/gmol succinic acid =

Page 6: CBE 250 Process Design Report

1.017 g glucose/g succinic acid

Number of fermenters required (calculated after flows were computed)

volume of water in feed: 699345 kg / .9922 kg/L = 704843 Lvolume of glucose in feed: 9328 kg / 1.560 kg/L = 5979 Lvolume of feed: 704843 L + 5979 L + 710822 Lnumber of fermenters: 710822 L / 100000 L/fermenter = 7.108 fermenters(To accommodate the carbon dioxide feed and to stay under the suggested limit, eight fermenters will be used.)

Fractional atom economy:

fractional yield of succinic acid from glucose: 2475 kg/batch / (9328-5661) kg/batch = .6749 (using net consumption of glucose)fractional yield of 1,4 butanediol from succinic acid: YS,P = fcA * SS,P = .9 * .76 = .657fractional yield of 1,4 butanediol from glucose: .657 * .6749 = .4434cost per batch of glucose: 535 $/metric ton / 1000 kg/metric ton * (9328-5661) kg/batch = 1962 $/batch (using average listed glucose price) [7]revenue per batch of glucose: .78 $/lb / .454 kg/lb * (9328-5661) kg/batch * .4434 = 2793 $/batch (using average of listed 1,4-butanediol price) [8]net income per year of glucose: 2793 $/batch - 1962 $/batch / 40 hr/batch * 8000 hr/year = 166400 $/year

maximum fractional yield of succinic acid from glucose: (2475+1061) kg/batch /(9328-5661) kg/batch = .9643 (using net consumption of glucose)maximum fractional yield of 1,4 butanediol from glucose: .657 * .9643 = .6335maximum revenue per batch of glucose: .78 $/lb / .454 kg/lb * (9328-5661) kg/batch * .6335 = 3991 $/batch (using average of listed 1,4-butanediol price) [7]maximum net income per year of glucose: 3991 $/batch - 1962 $/batch / 40 hr/batch *8000 hr/year = 405800 $/year

References

[1] Corti, Horacio et al. (2005) Octanol-water partition coefficient of glucose, sucrose, and trehalose. pdf.

[2] Song, H and Sang Yup Lee. (2005). Production of succinic acid by bacterial fermentation. pdf.

[3] Muzumdar, Arati Sudhirprakash B. Sawant and Vishwas G. Pangarkar. (2004). Reduction of Maleic Acid to Succinic Acid on Titanium Cathode. pdf.

Page 7: CBE 250 Process Design Report

[4] Wang, Xiaohai C. S. GONG, AND GEORGE T. TSAO. (1998)Bioconversion of Fumaric Acid to Succinic Acid by Recombinant E. coli. pdf.

[5] Jun et al. (2006). Effective purification of succinic acid from fermentation broth produced by Mannheimia Succiniciproducens. pdf. pg 1464.

[6] Collander, Runar. (1951). The Partition of Organic Compounds Between Higher Alcohols and Water. pdf. pg 776.

[7] Bulk Glucose - Buy Bulk Glucose Product on Alibaba.com. (2006). Retrieved December 15, 2015,from,http://www.alibaba.com/productdetail/bulkglucose_60316561747.html?spm=a2700.7724857.29.100.Cvp77m

[8] Chemicals A-Z. (2006, August 28). Retrieved Decemer 15, 2015, from http://www.icis.com/chemicals/channel-info-chemicals-a-z/