1. 1
Green Diesel Production Design for use as a
Petro-Diesel Additive
A.C.E. Green Diesel Production
Senior Design Group A
Cameron Mengel, Alexander Tooley, Eric Shockey

2. 2
Executive Summary
This report was commissioned to examine the profitability of producing green diesel as a
potential replacement for petroleum diesel. This analysis was done by first choosing our
reactants, our product rate, and then design a plant to produce our renewable diesel. After this
design was optimized, we then developed costing for all of our streams and equipment. Net
return on investment (NROI) computations were then completed to assess the feasibility of our
design. Based on actual renewable diesel plants, our final design led to a $3.67 per gallon of
renewable diesel to achieve a 10% NROI.
Our report finds the production of renewable diesel to not be competitive enough to be sold
against biodiesel. Based on the current selling price of petroleum diesel of approximately $2.27
per gallon [6], the additive that we produce is too expensive to be a viable option. Because of the
high variability of the price of soybean oil, this process is likely to become even more expensive
and therefore less competitive in the coming years. However, as the Environmental Protection
Agency enforces higher percentages of renewable diesel that must be in petroleum diesel, our
design may become viable to reach the requirement. The petroleum companies will have to pay a
higher price for the renewable additive. Also, if the price of soybean oil were to stabilize or the
price of petroleum diesel itself to increase, our design could become effective. Additionally, if
the United States government were to subsidize our plant so that a sustainable and greener fuel
could be produced, then our process would become more profitable and viable to begin building
it.

3. 3
Table of Contents
Introduction 4
Background 4
Product Market 4
Triglyceride Feedstock 5
Design and Sizing 6
Reactor 6
Separators 8
Heat Exchange Network (HEN) 9
Aspen Flowsheet 11
Economics and Costing 11
Reactor 11
Separators 13
Variable Costs 14
Net Present Value and Internal Rate of Return 14
Sensitivity Analysis 16
Safety 20
Emissions Inventory 22
Conclusions 23
References 25
Appendix A - Tables and Figures 27
Appendix B - Equations 31

4. 4
Introduction
Background
Today, petroleum diesel is a very popular choice as a fuel source. However, due to the limited
amount of petroleum diesel available and the negative environmental effects of combusting it,
other methods of fuel production have been researched. One such method is the production of
renewable diesel, also known as green diesel. Through different plant oils, renewable diesel can
be produced by the hydrotreating of the fatty acids. Hydrodeoxygenation is the process where the
oil is reacted to produce long hydrocarbon chains with only propane and only one or two other
by-products. Depending on the amount of excess hydrogen gas used in the process, the
hydrodeoxygenation reaction by-products could be carbon dioxide, carbon monoxide, and/or
water. The carbon dioxide produced by the combustion of the long hydrocarbon fuel is partially
balanced out because of the amount absorbed by plants during photosynthesis, so this is
generally regarded as a greener process. The greatest advantage of renewable diesel is the
sustainability of the feed source, because the fossil fuels will eventually run out, more
sustainable fuel sources are needed. While this is not the answer to global climate change, the
production of renewable diesel over petroleum diesel will help decrease the carbon dioxide
emissions from the burning of fossil fuels.
Product Market
Unlike biodiesel, renewable diesel can be a direct substitute for petro-diesel in current
automobile diesel engines. Additionally, there is the option to blend the renewable diesel with
petro-diesel in any proportion. With the current price of green diesel being greater than that of
petro diesel, immediate profitability would occur faster for our process if the green diesel

5. 5
produced would be sold directly to a petro-fuel company as a proportional petro-diesel fuel
additive. The United States Environmental Protection Agency (EPA) has set regulations for the
amount of renewable fuel that must be in all petroleum based fuels which have been raised for
2016 which increases the demand for a renewable, blendable diesel additive. Green diesel is
more attractive for this purpose because of its ability to be blended into petroleum diesel without
any further refining and in any proportion necessary. Petroleum diesel suppliers can either mix
biodiesel or our additive into their diesel so if ours is cheaper than the price of biodiesel our
product will be much more attractive with a higher cetane number as well. The cetane number is
not significantly changed to make the cloud point of mixed fuel unattractive. Also, consumers
would pay a premium for "green" alternative to fossil fuels. Green diesel has the potential to be
used in marine vessels or airplanes in the future too.
Triglyceride Feedstock
The main feedstocks available for the triglyceride feed include palm oil, soybean oil, yellow
grease, and tallow oil. The former two oils extracted directly from plants while the latter two are
from animals or from recycled fats and oils from food waste. Since the recycled food waste and
animal fat will not be as readily available as soybean oil and will have to go through extra initial
processing to liquefy the animal fat, a plant based feedstock would be beneficial. As shown in
table 1, soybean oil has a larger concentration of C18 triglyceride strands. Even though, soybean
oil costs $0.07 more per pound and has twice as many unsaturated bonds, the larger the amount
of C18 triglyceride strands makes the final green diesel product have a larger cetane number.
Having a larger cetane number is more beneficial as a fuel additive because it increases the
cetane number when mixed with petro-diesel and will not strongly effect the cloud point of the
diesel itself because of only being a percentage of the fuel. Being a fuel additive, an

6. 6
isomerization reaction is not necessary because doing so will only reduce the cetane number
which is an expenditure that is not necessary because blending our product will only slightly
increase the cetane number of petro diesel.
Table 1: Feedstock price and C18 percentage
Feedstock C18 (%) Price ($/lb.)[15] Mol Double Bonds per Mol
Palm 55 0.255 0.6
Soybean 90 0.3225 1.25
Yellow Grease 75 0.2413 0.8
Tallow 70 0.2411 0.48
Designand Sizing
Reactor
Based on the demand for green diesel and referring to how much green diesel UOP Honeywell
produces per year, the goal is to produce 52 metric tons, or 140 million gallons, of green diesel
per year. The first step to this design process was choosing a catalyst. The main options available
were Pd/C or NiMo/y-Al2O3.
After reading the research completed by Elvan Sari[13], the Pd/C was chosen due to its higher
selectivity and yield. Pd/C had a selectivity of 99.9% with a complete conversion, as compared
to NiMo/y-Al2O3 which only had a selectivity of 93%. These researchers used a 65:1 weight of
reactant to weight of catalyst to achieve the selectivity and yield stated above. Using this input, a
total catalyst mass of 915 kg of Pd/C will be placed in the hydrodeoxygenation reactor. For our

7. 7
reactor, we operated at 350° C and 50 bar to fully complete the reaction and avoid the generation
of side products.
To size our reactor, we used the data presented by Pacheco[10]. With their reported reactor size of
124.7 m3 and a triglyceride flow rate of 227 m3/h, our designed reactor volume was scaled up
from our triglyceride flow rate of approximately 1553 m3/h. This volume was then used to
calculate the length and diameter of the reactor using a ratio of 1.5 to 1. Because the
hydrodeoxygenation reactor was designed to be similar to a plug flow reactor, the Peclet
number[4] was researched to determine if the flow would behave accordingly. From the equation
given by Struck[16], the Peclet number for the reactor designed could be estimated by the catalyst
particle size, which is 6 microns, and the length of the reactor. This Peclet number confirms that
with a length to diameter ratio of 1.5, will give plug flow behavior. The resulting reactor design
specifications are tabulated in table 2.
Table 2: Reactor Specifications
Diameter (m) 8.98
Length (m) 13.46
Volume (m3) 853
Operating Pressure (bar) 50
Operating Temperature (°C) 350
Cbm ($ MM) 147.2

8. 8
Separators
The separators that will be needed to retrieve the green diesel from the water produced, recycle
the excess hydrogen, and dispose of the produced propane were established and modeled Aspen
Plus. For our flash drums and membrane separator, the volumes of the vessels were calculated
with the assumption that the vessels will have a residence time of 5 minutes when half full. Also
assuming a length to diameter ratio of 2.5, the specific dimensions were calculated and tabulated
below in table 3. The distillation column height was determined by the number of trays needed to
separate the water and the green diesel. The column was designed to have 2 feet space between
the 5 trays and have a total of 15 feet of extra space above and below the trays, as well as the
vapor flow rate through the column. The vapor volumetric flow rate through the column at
steady state led to the calculation of the diameter.
Table 3: Separator Specifications
Separating Vessel Flash 1 Flash 2 Membrane Separator Column
Diameter (m) 5.42 3.19 3.16 2.41
Length/Height (m) 13.6 7.97 7.89 7.62
Volume (m3) 313 63.7 61.7 34.76
Operating Pressure (bar) 10 25 25 10
Operating Temperature (°C) 210 25 25 -
Cbm ($ M) 1604 942.0 533.4 567.5
To separate the excess hydrogen gas from the other gases and liquids to recycle it back to the
feed, a membrane separator was designed. According to Acquaviva[1], a separator membrane
made of palladium alloy gives a separation recovery of 60% of the total gas flow through the
separator. To determine the size of the membrane, this specific membrane has a hydrogen flux

9. 9
rate of 250 standard cubic feet per hour per square foot of membrane. Knowing the flux rate and
the amount of hydrogen desired to be recycled, 721 ft2 of this membrane is needed. The
membrane also has a lifetime of 5 years and the cost of the membrane was added to variable cost
per year[1].
Heat Exchange Network (HEN)
We synthesized our heat exchange network using the composite curves for all streams that had to
be heated or cooled. Using the HEN Synthesis method to calculate the minimum energy
requirement for the hot utility. To make sure that we did not violate the 2nd law of
thermodynamics, 423.5 kW of cold utility to maintain the minimum temperature difference. Our
temperature pinch occurs when the cold streams are at their minimum at 50 °C. The heat cascade
table, in Appendix A2, shows the minimum energy requirements of each utility. Once we built
that we were able to match streams and build the heat exchange network. We had a minimum of
4 heat exchangers and were able to achieve that number. With 2 matched heat exchangers and 1
each using hot and cold utility, along with the condenser and reboiler that accompany the
distillation column.

10. 10
Figure 1: Minimum Energy Requirement Composite Curves
Without the heat integration network, the process would have used 23,050 kW of energy for
heating and 10,040 kW of energy for cooling. With heat integration between the streams, the
process only uses 14,340 kW of energy from hot utility and 1,346 kW of cold utility. The amount
of utility for steam was calculated using the latent heat of condensation which gave us the mass
flow of steam. For cooling water, the heat capacity and the change in temperature needed for
each stream was used to calculate the volume of cooling water needed. From that, the price per
amount of utility was calculated using the cost sheet from 2010, and then adjusted for inflation to
2016 rates using a 4% increase per year. Without the heat integration the annual utility cost for
the system would be $9.61 MM. With the heat integration the total utility cost is $5.57 MM. The

11. 11
heat integration saves $4.04 MM annually. The cost of the additional heat exchanger to
implement the heat integration is less than $250 thousand dollars which shows that the added
investment to decrease the variable cost is worth the investment.
Aspen Flowsheet
Figure 2: Process Flow Diagram with Heat Integration
Economics/Costing
Reactor
According to the graph shown below from the Colorado School of Mines Presentation[8], the
total cost of the hydrodeoxygenation reactor is dependent on the volumetric flow rate. Our

12. 12
design requires a feed a 10,000 bbl. of feed per stream day, which corresponds to a price of $130
million. Because this price is in reference to 2005, the rate of inflation needs to be accounted for
with the CEPCI. The actual price today would be $147.2 million.
Figure 3: Catalytic Hydrocracking Unit Costing[8]

13. 13
Separators
Using the vessel costing equations, in Appendix B, in chapter 22 of Seider and Seader[14], the
bare module costs were determined and are reported in Table 4. The same equations were used
for the cost of the column with the addition of the cost of the 5 sieve trays.
The cost of the membrane is $1000 per square foot. With the lifetime of the membrane being 5
year, it is only necessary to buy 721 ft2 of new membrane every 5 years. This pricing was
integrated in our variable costs per year which came out to be $144,000 per year.
Table 4: Fixed Investment of all Process Units
Bare Module Costs ($ MM)
Reactor 147.16
Flash 1 1.604
Flash 2 0.942
Membrane Separator 0.533
Column 0.567
Column Condenser 0.086
Column Reboiler 0.227
H2C1 0.131
H1C1 0.237
HUT 0.122
CUT 0.086
Catalyst 6.13
Membrane 0.721
Total 158.5
FI VGA 331

14. 14
Variable Costs
Table 5: Variable Costs
kg/year x 106 $/kg $ MM/year
Hydrogen 20.03 1.40[3] 28.05
Soybean Oil 495 0.71[15] 351
Utilities - - 5.57
Catalyst 190.4 kg/year 6440[11] 1.23
Membrane 721 ft2/5 years $1000 /ft2[1] 0.144
Net Present Value and Internal Rate of Return
The net present value of the project after 11 years and at an estimated discount rate of 25% is
negative $72 MM. However, the net cash flow of that year is $177 MM, so the net present value
will begin to increase toward positive very quickly in the next few years.

15. 15
Figure 4: Net Present Value (NPV) graph
The internal rate of return for our project to make the NPV zero at the end of this production
period is 16%.

16. 16
Figure 5: Internal Rate of Return for our project is 16%
Sensitivity Analysis
To understand the impact of how soybean oil price will affect our NROI and thus the price at
which we will need to sell our product at, a sensitivity analysis was performed. To do this, the
average monthly price range for soybean oil was found on Indexmundi[15] for the past 25 years,
which can be seen below.

17. 17
Figure 6: Price of Soybean Oil over Time[15]
Using figure 6, we were able to determine a range of prices for soybean oil to assess. We chose
to perform our analysis of soybean oil price over the range of $0.50 to $1.50 per kilogram to
account for any variation in the near future. We then performed NROI calculations with the
selling price range of $2.00 to $5.00 to find out what our NROIs would become with any market
variations. The contour plot of this data can be seen in figure 7.

18. 18
Figure 7: Net Return on Investment Contour Plot
As the price of soybean oil exceeds $800 per metric ton, the price per gallon for green diesel
needed to reach 10% NROI climbs toward $4.00. At this point, we suggest to use a price that
will give a lower NROI so that our green diesel can remain competitive with the petro diesel
prices. This price adjustment is a result of the tendency of the general population purchasing
petro diesel over green diesel because, even though some of the population would pay extra to be
more environmentally friendly, our product would be almost twice the cost of petro diesel at
today's rates.
We also examined the trend of pricing of petro diesel to that of biodiesel. As can be seen in the
figure below, the price of petro diesel has remained lower than that of biodiesel since 2007[2].

19. 19
Upon further analysis of these results, this pricing was as such for two reasons; one is that the
process of making biodiesel is more expensive, which is the main factor controlling its price, and
that because of the size of petro diesel companies, which allows them to take losses to remain
competitive and have lower prices than biodiesel companies to push consumers to buy petro
diesel.
Figure 8: Price of Diesel and Biodiesel per Gallon over Time[2]
We had determined that our product would be better sold as a blend to the petrodiesel
companies. Our product can be blended into petroleum diesel in any amount. Our product would
be sold to the petroleum companies at the high price close to that of biodiesel, but the blend
would be sold to the public depending on the amount that is put into the petroleum diesel. As of
now, a blend of 20% renewable diesel would only raise the price at the pump from $2.27 to
$2.55. The percentage of green diesel to price per gallon is a linear correlation. The EPA has

20. 20
begun to set regulations on the composition of petroleum based fuels and a regulated amount of
renewable fuel in them is the first step to increase the sustainability of the fuel industry.
Figure 9: Price per gallon of diesel at different blends of green diesel
Safety
Material Safety Data Sheets were gathered for all the chemicals that are a part of our process.
The most common hazard for the chemicals is a fire hazard. This makes sense because we are
producing fuel for internal combustion engines, which must be flammable. None of the
chemicals are known human carcinogens, teratogens, or mutagens. The control of the emissions
from this plant are mainly for environmental impact, specifically in the life cycle assessment
impact category of global climate change. We are producing green diesel because it is a much
more sustainable fuel with natural feedstock that doesn't deplete the Earth's oil resources.

21. 21
Table 6: NFPA Hazard Diamond Information (scale from 0-4)
Health Hazard Fire Hazard Reactivity
Hydrogen 0 4 0
Trilinolein 0 0 0
Triolein 1 1 0
Tristearin 1 1 0
Octadecane 1 1 0
Propane 2 4 0
The substance that needs to be handled and contained with the most caution is the hydrogen gas.
Hydrogen gas is extremely flammable and has an explosive range from 4%-74% by volume.
This means that at almost any concentration in a room the gas will explode if an ignition source
occurs. Hydrogen is not toxic, but it does displace air in a room which can cause asphyxiation
because of the lower oxygen concentration. At concentrations where it can cause asphyxiation it
also creates a flammable atmosphere which is much more dangerous. Hydrogen is both odorless
and colorless, making detection more difficult.
The next most dangerous compound is the propane that is created as a byproduct of the reaction.
The propane is a valuable byproduct because of its use as a fuel for heating and energy
integration. However, it also is an extremely flammable substance. It has flammability limits of
2.2%-9.6% by volume. This is a much smaller range than that of hydrogen gas and making it
much easier to control. The fire hazard is much more dangerous than the other hazards.
For all of these chemicals, ingestion and inhalation should be avoided. All proper personal
protective equipment should be used when handling these materials including goggles, flame
resistant gloves, and flame retardant clothing. Personal protective equipment should especially

22. 22
be used when handling the hydrogen and the propane gases, because these are the most
dangerous and have the highest potential to cause harm.
Emissions Inventory
Lastly, a gate-to-gate emissions assessment was completed at a basic level to determine the
approximate emissions produced from our manufacturing design. We assumed that all of the
steam used for heating in this process was from the burning of natural gas. We also assumed that
all of the diesel and propane in this process would eventually be burned as a fuel, thus
contributing to the emissions. From table 7 shown below, our main emission is carbon dioxide
which means that the environmental concern of our plant is global climate change. The other
significant emissions are carbon monoxide which is a very toxic gas to humans, nitrous oxides
and sulfur dioxide which have the potential to cause acid rain. Nitrous oxide also contributes to
the eutrophication of the environment, or the absorption of the dissolved oxygen in water sources
by the rapid growth of algae. The emissions from the plant came from the propane created,
which was assumed to be burned for energy and heat, the excess hydrogen gas that wasn’t able to
be recycled, and the small amount of biodiesel that gets separated, which is also assumed to be
burned with the propane. Since all of the emissions from the plant are burned, we assumed
complete combustion in an incinerator operating at 950 °C to ensure complete combustion and
creation of CO. The CO, NOx and SOx emissions are all created by the burning of natural gas to
create the steam used as hot utility for heating. The breakdown of the products of combustion of
natural gas were primarily CO2
[9].

23. 23
Table 7: Manufacturing Emissions Report
Emissions Report Metric ton/yr.
CO2 112514
CO 7
NOx 16
SOx 0
These emissions are only from the manufacturing stage in the life cycle of the product. During a
full life cycle assessment, the cycle would be carbon neutral because the carbon used to create
the diesel fuel has to be gathered by the soybean plants in order to grow. However, the
transportation, and heating during the process will create emissions that will not be relieved by
the crops used to create the diesel.
Conclusions
After our analysis, the economics of this venture have seemed unattractive. Because of the high
costs of the equipment needed and the high cost of our reactants, our renewable diesel additive
requires a much higher selling price than that of standard petroleum diesel. To achieve a NROI
of 10%, our selling price has to be $1.40 per gallon higher than the average petroleum diesel
price of $2.27. This makes our product unattractive as the price of our product is almost twice
the price of the petroleum diesel. However, there are potential ways to make our process more
effective and decrease this price gap. If the price of soybean oil were to drop again due to its high
variability, our process would quickly become much less expensive. However, this variability
would likely work against us, as the data provided by Indexmundi[15] appears to show that the

24. 24
price of soybean oil will be going up in the near future. Another way that our process could be
more viable is funding by the federal government. Because millions are spent by the United
States to be more environmentally friendly and sustainable, it is likely that we would be able to
secure some of the funding to pay for some of our initial startup costs. However, due to a lack of
information, this outlet could not be explored.

25. 25
References
[1] Acquaviva, Jim. "High-Performance, Durable, Palladium Alloy Membrane for Hydrogen
Separation and Purification." U.S. Department of Energy. Pall Corporation, 19 May
2009. Web. 4 May 2016.
[2] "Clean Cities Guide to Alternative Fuel Price Report." Energy Efficiency & Renewable
Energy (2016): n. pag. Alternative Fuels Data Center. U.S. Department of Energy, Jan.
2016. Web. 4 May 2016.
[3] Doty, F. "A Realistic Look at Hydrogen Price Projections." EV World. 5 Mar. 2004. Web. 6
May 2016.
[4] Fulger, and Gurmen. "Chapter 12 - Diffusion and Reaction in Porous Catalysts." Professional
Reference Shelf. University of Michigan, 2008. Web. 09 May 2016.
[5] Gao, Danny, Yang Xiao, and Arvind Varma. "Guaiacol Hydrodeoxygenation over Platinum
Catalyst: Reaction Pathways and Kinetics." - Industrial & Engineering Chemistry
Research (ACS Publications). American Chemical Society, 13 Oct. 2015. Web. 09 May
2016.
[6] "Gasoline and Diesel Fuel Update." U.S. Energy Information Administration. U.S. Energy
Information Administration, 9 May 2016. Web. 11 May 2016.
[7] Gerber, M. A., J. G. Frye, L. E. Bowman, J. L. Fulton, L. J. Silva, and C. M. Wai.
"Regeneration of Hydrotreating and FCC Catalysts." Applied Catalysis (1999): n. pag.
Web.

26. 26
[8] Jechura, John. "Hydroprocessing: Hydrotreating & Hydrocracking." (2016): n. pag. Colorado
School of Mines, 26 Jan. 2016. Web.
[9] "Natural Gas and the Environment." NaturalGas.org. N.p., 20 Sept. 2013. Web. 11 May
2016.
[10] Pacheco, Manuel A., and Carlos G. Dassori. "Hydrocracking: An Improved Kinetic Model
and Reactor Modeling." 9 Sept. 2010. Web. 30 Apr. 2016.
[11] "Palladium Heterogeneous Catalyst." Alfa Aesar. Alfa Aesar, n.d. Web. 6 Apr. 2016.
[12] Petri, John A., and Terry L. Marker. Production of Diesel Fuel from Biorenewable
Feedstocks. UOP Llc., assignee. Patent US 7511181 B2. 31 Mar. 2009. Print.
[13] Sari, Elvan. "Green Diesel Production via Catalytic Hydrogenation/Decarboxylation of
Triglycerides and Fatty Acids of Vegetable Oil and Brown Grease." Diss. Wayne State
U, 2013. Aug. 2013. Web. 6 Apr. 2016.
[14] Seider, Warren D., J. D. Seader, Daniel R. Lewin, and Soemantri Widagdo. "Cost
Accounting and Capital Cost Estimation." Product and Process Design Principles:
Synthesis, Analysis and Design. 3rd ed. S.l.: John Wiley and Sons, 2009. 534-97. Print.
[15] "Soybean Oil." Indexmundi. Indexmundi, 5 Apr. 2016. Web. 6 Apr. 2016.
[16] Struk, Peter M. "Modeling of Catalytic Channels and Monolith Reactors." Diss. Case
Western Reserve U, 2007. Modeling of Catalytic Channels and Monolith Reactors. Jan.
2007. Web. 9 May 2016.

27. 27
Appendix A - Tables and Figures
Table A1: Stream Table
Table A2: Heat cascade table for heat integration
T (interval) C = mCph-mCpc Q (kW) sum of Q (kW) add heat
0.00 1444.69
350-340 -33.86 -338.597 -338.60 1106.09
340-200 12.13 1698.332 1359.74 2804.42
200-190 24.23 242.2847 1602.02 3046.71
190-50 -21.76 -3046.71 -1444.69 0.00
50-15 12.10 423.4134 -1021.27 423.41

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Figure A1: NROI vs. Price of Soybean Oil assuming a Selling Green Diesel Price of $3.70/gal

29. 29
Figure A2: Price of Green Diesel per Gallon vs. Price of Soybean Oil assuming a 10% NROI

30. 30
Figure A3: Venture Guidance Appraisal for the Process

31. 31
Appendix B - Equations
Pressure Vessel (Distillation Column) Cost Equations
𝐶 𝑃 = 𝐹𝑀 𝐶 𝑉 + 𝐶 𝑃𝐿
Horizontal vessels for 1000 < W < 920000 lbs
𝐶 𝑉 = exp⁡{8.9552 − 0.2330[ln 𝑊] + 0.04333[ln 𝑊]2}
Vertical vessels for 4200 < W < 1000000 lbs
𝐶 𝑉 = exp⁡{7.0132+ 0.18255[ln 𝑊] + 0.02297[ln 𝑊]2}
Towers for 9000 < W < 2500000 lbs
𝐶 𝑉 = exp⁡{7.2756+ 0.18255[ln 𝑊] + 0.02297[ln 𝑊]2}
W is the weight of the vessel in lbs.
Horizontal vessels for 3 < DI < 12 ft
𝐶 𝑃𝐿 = 2005( 𝐷𝑖)0.20294
Vertical vessels for 3 < Di < 21 ft and 12 < L < 40 ft
𝐶 𝑃𝐿 = 361.8( 𝐷𝑖)0.73960 ( 𝐿)0.70684
Towers for 3 < Di < 24 ft and 27 < L < 170 ft
𝐶 𝑃𝐿 = 300.9( 𝐷𝑖)0.63316 ( 𝐿)0.80161
Di is the diameter of the vessel in feet, and L is the length of the vessel in ft
𝑊 = 𝜋( 𝐷𝑖 + 𝑡 𝑆)( 𝐿 + 0.8𝐷𝑖) 𝑡 𝑆 𝜌
Di is the diameter of the vessel in ft. tS is the shell thickness in ft. L is the length of the vessel in
ft. Rho is the density of carbon steel which is 490 lb/ft^3.

32. 32
NROI Equations
𝑁𝑅𝑂𝐼 = (1 − 0.38)(
𝑅 − 𝐶𝑂𝑆
𝐹𝐼 + 𝑊𝐶
)
𝐶𝑂𝑆 = 1.06( 𝑉𝐶 + 0.14𝐹𝐼 + 3600000)
𝑊𝐶 =
𝑉𝐶
6
+
0.14𝐹𝐼 + 3600000
12
𝑊𝐶 = 𝑤𝑜𝑟𝑘𝑖𝑛𝑔⁡𝑐𝑎𝑝𝑖𝑡𝑎𝑙
𝐶𝑂𝑆 = 𝑐𝑜𝑠𝑡⁡𝑜𝑓⁡𝑠𝑎𝑙𝑒𝑠
𝑉𝐶 = 𝑣𝑎𝑟𝑖𝑎𝑏𝑙𝑒⁡𝑐𝑜𝑠𝑡
𝐹𝐼 = 𝑓𝑖𝑥𝑒𝑑⁡𝑖𝑛𝑣𝑒𝑠𝑡𝑚𝑒𝑛𝑡
𝑅 = 𝑟𝑒𝑣𝑒𝑛𝑢𝑒