Aspen simulation

BIO DIESEL
1. INTRODUCTION
LITERATURE SURVEY
Diesel fuel is extensively used in heavy trucks, derived from rapeseed,
soybean, palm, sunflower, city transport buses, locomotives, electric generators,
coconut, linseed, etc. However, in India, it is not farm equipments, underground
mine equipments and viable to produce biodiesel using such edible oil to plays an
important role in the economy of India. Produce biodiesel because of a big
difference in demand various forms of gaseous, liquid and solid pollutants and
supply of edible oils. In this context, crops that from diesel engine can endanger
human health and can produce non-edible oils such as Jatropha, Karanja, damage
the ecological environment. Diminishing Mahua, Cotton seed, Polanga, Refinery
waste oil, Palm oil etc. Petroleum reserves and environmental consequences in
substantial quantities can be grown in large scale on of exhaust gases from diesel
fuelled engines are some of non-cropped waste lands.
At current production levels, biodiesel requires a subsidy to compete
directly with petroleum-based fuels. However, Current production levels are 20–
25 million gallons/year, but achieving current production levels of 500 million to
1 billion gallons/year should be feasible.
The combined vegetable oil and animal fat production in the India totals about
35.3 billion
Pounds per year. This production could provide 4.6 billion gallons of biodiesel.
However, the
Annual consumption of diesel fuel is about 33 billion gallons. If all of the
vegetable oil and animal fat produced in The India were available to produce
biodiesel, it would only displace about 14% of the current demand for Onhighway
diesel fuel.
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1. Bio-Fuels
1.1 Classes of biofuels
Bio fuels fall into three classes
The first class is material produced for the fuel production, energy
plantation, and bi-products of other agricultural activities and materials that could
be classified as wastes. The economics of using such fuels depend on which class
the fuel belongs to.
The second class fuels that are produced as processing bi products, offer
better economic opportunities. Baggase, Sawmill refuse, Rice husk etc. are also
used as fuels.
The manufacturing process leading to their creation produces a
concentration of material is still valuable because of its immediate availability.
The drawback with some of these fuels is that they are produced on a seasonal
basis.
The third class bio fuels include materials that have only marginal fuel
value, and may have a negative useable energy potential. These materials often
require a considerable energy input into their collection and processing. Their use
as a fuel is dependent on other benefits such as environmental hazard production
being the primary reason for collection and combustion.
1.2 Biofuels and the environment
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Sulphur emissions are essentially eliminated with pure biodiesel
When biodiesel is burned the exhaust gases does not contain sulphur oxides
and sulphates. Criteria pollutants are reduced with the use of biodiesel.
Tests show the use of biodiesel in diesel engines results in substantial
reductions of unburned hydro carbons, carbon mono oxide, and particulate matter.
Emissions of nitrogen oxide stay the same or slightly increased.
Carbon monoxide
The exhaust emissions of carbon monoxide from biodiesel are on average
47% lower carbon monoxide emissions from biodiesel.
Particulate matter
Breathing particulate has been shown to be a human health hazard. The
exhaust emissions of a particulate matter from biodiesel are about 47% lower than
overall particulate matter emissions from diesel.
Hydro carbons
The presence of hydrocarbons in the exhaust emissions are almost reduced
when biodiesel is used.
Nitrogen oxides
Nox emissions from biodiesel increase or decrease depending on the
engine family and testing procedures. Nox emissions from pure biodiesel increase
on average by 10%. However, biodiesel with lack of sulphur allows the use of
Nox control technologies that can’t be used with convectional diesel.
Additionally, some companies have successfully developed additives to reduce
Nox emissions in biodiesel blends.
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Biodiesel reduces the health risks associated with petroleum diesel
Biodiesel emissions show decreased levels of Polycyclic aromatics
Hydrocarbons, which have been identified as potential cancer causing compounds
in health effects testing, PAH compounds were reduced by roughly 50%.Targeted
NPAH compounds were also reduced.
Dramatically with biodiesel, with 2-nitri fluorine and 1-nitro pyrene
reduced to only trace values.
Successfully alternate fuels fulfill environment and energy security needs
without sacrifying operating performance. Operationally, biodiesel performs very
similar to low sulpur diesel in terms of power, torque without major modifications
of engine or infrastructure. Biodiesel offers a similar power to diesel fuel.
One of the major advantages of biodiesel is the fact it can be used in an
existing engine as the fuel ingestion equipment with little impact to operating
performance. Biodiesel has a higher cetane number than diesel fuel. In over 15
million miles in field demonstrations biodiesel showed similar fuel consumption,
horse power, torque and mileage rates as a convectional diesel fuel.
1.3 Biodiesel and India
India imports more than seventy percent of the crude oil. This is an
incredible dependency on foreign oils and an alternate should be found and the
cultivation of bio crops could be taken up to serve two major objectives. Firstly
with proper selection of low nutrition demanding oil bearing species, the waste
land can be brought under compact plantation. Secondly, rejuvenation of the
waste land can also be achieved by upgrading the soil quality by addition of seed
meal, which is obtained after extraction oil that has a high nutrition value India
has a tropical advantage and several species capable of giving oil bearing seed are
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known to grow. India can produce about 4-5million tonns per annum of biodiesel,
which is 10% of current diesel demand.
1.4 Indian energy scenario
India faces more problems that just need for reliable energy supply. Even
if the environment is able to acquire rights to natural gas and crude oil supplies
all around the world, the problem does not end there. India faces a major shortage
of refining capacity. As a result prices of diesel, petrol, kerosene can go through
the roof even if the crude oil price moves up slowly.
The refineries all around India are old and mainly acquired from the Soviet
Union many years back. They need to be replaced soon. They operate at a much
lower capacity due to maintenance needs and cause bad pollution all around.
Oil accounts for about 30% of India’s roughly 5.4 billion barrels in oil
reserves are located in the Mumbai high, upper Assam, Cambay, KrishnaGodavari and kaveri basis. The offshore Mumbai high field by far India’s largest
producing field with current output of around 260,000 barrels per day.
India’s average oil production level for 2003 was 819,000bbl/day of which
660,000 bbl/day was crude oil. India had net oil imports of over 1.4 million
bbl/day in 2003. Even with these new reserves, India domestic natural gas supply
is not likely to keep pace with demand and country will have to import.
In such a situation, only renewable sources like bio fuels can answer the
current demand. There is an urgent need to realize the importance of fuel like
biodiesel and take measures to bring them in to vague.
1.5 What is a bio fuel?
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BIO FUEL is any fuel that derives from bio mass, recently living organisms
or their metabolic by products, such as manure from cows. It is a renewable
energy source unlike the other natural resources such as petroleum, coal and
nuclear fuels. The carbon dioxide by growing plants, so burning it does not result
in a net increase of carbon dioxide in Earth`s atmosphere. As a result, biofuels are
seen by many as away to reduce the amount of carbon- dioxide released in to the
atmosphere by using them to replace non-renewable sources of energy.
There are three classes of bio fuels:
1. Solid bio fuels:
Wood
Straw
Animal wastes
2. Liquid bio fuels
Bio alcohols
Biologically produced oils can be used in diesel engines.
Straight vegetable oils (SVO)
Waste vegetable oil (WVO)
Biodiesel obtained from trans-esterification of animal fats, vegetable oils.
3. Gaseous bio fuels
Methane
Wood gas
1.6 What is biodiesel?
Biodiesel is the name for a variety of a ester based fuels (fatty esters)
generally defined as monoalkyl esters made from vegetable oils such as soybean
oil, canola oil (or) hemp oil (or) sometimes from animal fats through a simple
trans-esterification process.
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Biodiesel burns clean which results in a significant reductions of the types
of pollutants that contribute to smog and global warming and emits up to 85%
fewer cancer causing agents.
1.7 History of biodiesel
The concept of using vegetable oil as an engine fuel dates back to 1895
when Rudolf Diesel developed the first engine to run on peanut oil, as
demonstrated at the world exhibition in Paris in 1900. Unfortunately, R.Diesel
died in 1913 before his vision of a vegetable oil powered engine was fully
realized. There is documentary recording that biodiesel trans-esterification
technology experimentation was first conducted as early as 1853 by scientists E.
Duffy and J. Patrick, many years before Rudolf’s diesel engine became
functional. After R.Diesel death the petroleum industry was rapidly developing
and produced a cheap byproduct diesel fuel “powering a modified diesel engine”.
Thus, clean vegetable oil was forgotten as a renewable source of diesel. The first
public recognition of trans-esterification technology became a patent asset on 31st
august 1937 when G.Chavanne of the University of Brussels was granted a patent
license for alcholysis of vegetable oils using ethanol or methanol with the purpose
of separating the fatty acids from the glycerol by means of replacing glycerol with
short linear alcohols. It was the earliest account of the production as well as the
terminology “biodiesel”.
Today’s diesel engines require a clean–burning, stable fuel operating under a
variety of conditions. In the mid 1970’s fuel storage spurred interest in
diversifying fuel resources and thus biodiesel as fatty esters was developed as an
alternate to petroleum diesel. Later in 1990’s, interest was raising due to the large
pollution reduction benefits coming from the use of biodiesel. The use of
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biodiesel affected by legislation and regulations in all countries. On February 9,
2004 the government of Philippines directed all of its departments to incorporate
1%by volume coconut biodiesel in diesel fuel for use in government vehicles.
On Oct 27, 2003 in United States, by 1995 10% of all federal vehicles were to be
using alternate fuels to set an example for the private automotive and fuel insides.
Several studies now funded to promote the use of blends of biodiesel and heating
oil. In USA soybean oil is the principle oil being utilized for biodiesel.
Biodiesel is defined as the esters of long chain fatty acids. Biodiesel is a renewable
and biological source that has been receiving more attention all over the world
due to the energy needs and environmental consciousness. Biodiesel is monoalkyl esters of long chain fatty acids, which falls in the carbon range C12-C23.
Biodiesel is an alternative fuel for diesel engines that is produced by chemically
reacting a vegetable oil or animal fat with an alcohol such as methanol. The
reaction requires a catalyst, usually a strong base or an acid and produces new
chemical compounds called methyl esters. It is these esters that have come to be
known as biodiesel.
PROPERTIES OF BIODIESEL
Common name
Biodiesel
Common chemical name
Fatty acid (m)ethyl ester
Chemical formula range
C14 –C24 methyl esters
2
Kinematic viscosity range (mm /s, at 313
3.3-5.2
K)
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3
Density range(kg/m , at 288K)
860-894
Boiling point range(K)
>457
Flash point range (K)
420-450
Vapor pressure (mm Hg, at 295 K)
<5
Distillation range (K)
470-600
Solubility in water
Insoluble in water
Physical appearance
Light to dark yellow, clear liquid
Odor
Light musty/soapy odor
Biodegradability
More biodegradable than
petroleum diesel
Reactivity
Stable but avoid strong oxidizing
agents
Uses and applications of bio-diesel:
Some of the advantages of using biodiesel as a replacement for diesel fuel are:
 Renewable fuel, obtained from vegetable oils or animal fats.
 Low toxicity, in comparison with diesel fuel.
 Degrades more rapidly than diesel fuel, minimizing the environmental
consequences of biofuel spills.
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 Lower emissions of contaminants: carbon monoxide, particulate matter,
poly cyclic aromatic hydrocarbons, aldehydes.
 Lower health risk, due to reduced emissions of carcinogenic substances.
 No sulphur dioxide (SO2) emissions.
 Biodiesel is plant-based and adds no CO2 to the atmosphere.
 The ozone-forming potential of biodiesel emissions is nearly 50% less than
conventional diesel fuel.
 Biodiesel is environmentally friendly: it is a renewable energy.
Problem statement
To produce 213.456 tons/day of biodiesel using sesame oil by alkaline
transesterification by using Aspen simulation
Biodiesel Production Methods:
1 Alkaline Catalyzed Trans esterification Process
2 Acid Catalyzed Trans esterification Process
3 Acid-alkaline Catalyzed (Two Stages)
4 Non Catalyzed Supercritical Trans esterification Process
5 Enzyme Catalyzed Trans esterification Process
Selection of Process:
• Alkaline Trans esterification process is selected to produce biodiesel
because it requires less time and it can gain higher yields.
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• This process is most effective for feedstock with FFA level below 2% as it
is reported to proceed about 4000 times faster than acid catalyzed
esterification process.
• Base catalysts such as sodium methoxide, sodium hydroxide, and
potassium methoxide potassium hydroxides have been successes fully used
at industrial level for the production of bio diesel.
• It becomes ineffective when free fatty acid level exceeds 2% because FFA
reacts with the most common alkaline catalyst and forms soap which
inhibits the separation of ester from glycerin.
Trans esterification:
• Trans esterification is the process of exchanging the organic group R″ of
an ester with the organic group R′ of an alcohol.
Model The process was modeled in Aspen to determine optimal conditions to
maximize the conversion of vegetable oil to biodiesel.
Vegetable oil is a complex solution which was represented as triolein in the
simulation. Biodiesel was represented as methyloleate. Triolein is reacted with
methanol to produce methyloleate and glycerol according to the reaction below.
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The process model involved two RGibbs reactors operated in series, as shown in
the process flowsheet below. Triolein (FEED-OIL) and methanol (FEEDMET)
were fed into the first RGIBBS reactor (R1) in stoichiometric amounts. The outlet
of this reactor (R1-OUT) was separated in a flash drum (R1-FLASH) to remove
unreacted methanol (METOH-R1) to be passed to the second reactor. The two
phase liquid leaving the first flash drum (PROD1) was then separated in a
decanter into glycerol (GLYC1) and a mixture of the unreacted triolein and
biodiesel (R2-FEED). The triolein-biodiesel mixture then entered the second
RGibbs rector (R2) with recycled methanol (REC-MET).
The second reactor product stream (R2-OUT) was then flashed to remove and
recycle methanol (METOH-R2), this stream was split (RECSPLIT) to allow a
purge stream (PURGE). The bottoms liquid (PROD2) was decanted (DECANT2)
to separate the biodiesel (BIODIESEL) and glycerol (GLYC-2). The glycerol
streams were combined (GLYC-MIX) to produce the final glycerol product as a
process output. An overview of the process can be seen in the Figure 1: Biodiesel
production process flow sheet Figure 1 below.
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CHALLENGES
Property Estimation Vegetable oil is a mixture of triglycerides extracted from
plant matter; these molecules are derived from glycerol and three long-chain fatty
acids. These fatty acids vary widely in length and degree of saturation and so their
properties vary as well. Triolein (CAS 122-32-7) is a vegetable oil unique in that
all of its fatty acid groups are the same, oleic acid. It has been shown to make up
4-30% of olive oil (Thomas, 2002). Triolein was chosen to represent vegetable
oil in the process so the transeterification process had only two products, glycerol
and methyl-oleate. Triolein has been used as a vegetable oil analogue in several
case studies and process optimizations of biodiesel production plants (West,
Posarac, & Ellis, 2007) (Mueanmas, Prasertsit, & Tongurai, 2010) (Dhar &
Kirtania, 2009).
Although the properties for triolein were available in the ASPEN data banks, an
error arose when trying to run the model (see Appendix B: Missing Property
Parameters). Ideal gas heat capacity data for Triolein was missing and could not
be determined through property estimation. Values for ideal gas heat capacity
were manually entered; the pure-component data came from the work of Noor et
al. (Noor Azian Morad, A.A. Mustafa Kamal, F. Panau, & T.W. Yew, 2000). The
pure component and mixture properties were re-estimated using this data. The
property data setup is shown in Figure 2 below.
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Figure 2: Ideal gas specific heat data used to re-initialize property estimation
for Triolein
Once the ideal gas heat capacity data had been entered and the properties
reestimated the all input specifications were translated and the simulation
generated results.
Convergence
ASPEN uses flowsheet convergence blocks to solve iterative calculations arising
from recycle or tear streams and design specifications. The blocks determine how
guesses for recycle streams and design spec variables are updated from iteration
to iteration. Convergence can be manipulated in ASPEN by changing the
tolerance, algorithm, or the maximum number of iteration steps (Sup Yoon &
Kim, 2011). The process taken to converge the simulation will be discussed here.
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Originally, the model was designed so all unreacted methanol was returned to the
frontend of the process (see Appendix E: Proposed Process Flow sheet). There
was no purge stream specified so at steady state there was a hold-up of methanol
in the process. This generated a convergence error in the
methanol recycle stream, as every iteration would return a higher value than the
time before. The error generated in the simulation control panel is shown in
Figure 3 below.
Figure 3: Convergence solver error report generated in simulation control
panel
The error was initially fixed by adjusting the Convergence options. It was
believed that the error was
Caused by the complex system of recycling reactants from three points in the
process. The tolerance was increased from .0001 to .001 and the simulation run
again. The model would not converge after 30 iterations, the default number, so
the maximum number of iterations was increased to 500. This meant the process
was undertaking a maximum of 500 calculation loops to converge the model to
within 0.1%.
The simulation was converged to <0.099% error within ~80 iteration. While this
appeared to solve the problem it did not address the underlying process error.
Upon investigating the stream results it was determined that methanol was
building up in the process without an adequate purge stream. The design was
revised to include a stream splitting block to purge %10 of the methanol coming
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from the second reactor flash drum. The convergence options were reset to
default, 0.01% tolerance and 30 iterations, and the simulation was reinitialized.
With the purge stream in place the simulation was capable of producing results
without warnings or convergence errors.
PROCESS STEPS:
Heating of Oil:
• In order to speed up the reaction, the oil must be heated. The ideal
temperature range is 50º C to 60º C.
• Proportion of Sesame oil, Sodium Hydroxide (alkali catalyst) and
Methanol taken are as follows: 1 : 6 Mixing of Methanol and catalyst:
• The purpose of mixing methanol and the catalyst (NaOH) is to react the
two substances to form methoxide.
• Firstly, NaOH is mixed slowly with alcohol in a three-necked round bottom
flask, stirring continuously.
• NaOH does not readily dissolve into methanol. It is best to turn on the
mixer to begin agitating the methanol and slowly pour the NaOH in.
• When particles of NaOH cannot be seen, the methoxide is ready to be
added to the oil. This can usually be achieved in 20 –30 minutes.
Heating and mixing:
• Oil is poured slowly in the prepared Sodium methoxide mixture with
continuous stirring and then heated at 50-60 °C for about 90 minutes.
• A magnetic stirrer works fine as a mixer. Too much agitation causes
splashing and bubbles through vortexing and reduces mix efficiency. There
should be a vortex just appearing on the surface.
• Adjust the speed, or the pitch or size of the stirrer to get the right effect.
The Transesterification process separates the ethyl esters from the glycerin.
Now the whole system should be cooled and the mixture allowed settling
for at least 12 hours.
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Settling and separation:
• The ethyl esters (biodiesel) will be floating on top while the denser glycerin
will have congealed on the bottom of the container forming a hard
gelatinous mass. Then carefully decant the biodiesel.
• The semiliquid glycerin has a dark brown color and the biodiesel is honey
colored.
• The separated layer of Biodiesel is then fed to a batch distillation unit for
the recovery of ethanol and water. The temperature is maintained around
105 °C. The impure Biodiesel is washed with water. Two layers are
formed, upper layer being Biodiesel and the lower layer being water.
• Now the Biodiesel is separated from the water by a separating funnel. This
Biodiesel may contain a small percentage of water and so it is then dried
by passing through silica gel.
Overall Material Balance
Transesterification reaction is the reaction to produce bio diesel from tri glyceride.
Refinery waste has the composition like:
- Palmitic acid
- Stearic acid
- Linoleic acid
But it mostly contains of Oleic acid of about 51.6% So
we show the balance for this compound.
Molecular weight of oil=C57H104O6
= (60*12) + (101*1) + (6*16)
=917 wt units
Molecular weight of methanol=CH3OH =32 wt units
Molecular weight of bio diesel=CH3OCOC18H34
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= (20*12) + (37*1) + (2*16)
=309 wt units
Molecular weight of glycerol=C3H8O3
= (3*12) + (3*16) + (8*1)
=92 wt units
Block
In (Kg/hr)
Out(kg/hr)
Relative
Difference
3757.67149
3757.67
2.42036778E-16
MIXER 2
12612.1631
12612.2
2.15501016e-12
HEAT
EXCHANGER
21466.6547
21466.6547
CSTR
12612.1631
12612.2
-1.87492519e-14
DISTILLATION
COLUMN
12612.1631
12612.1629
1.23652039e-08
PUMP
10777.021
10777.021
3.37568127e-16
SEPARATOR
10777.021
10777.021
-1.68784063e-16
MIXER 1
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DISTILLATION
COLUMN
9856.07386
9856.07386
-1.84555172e-16
ENERGY BALANCE
Here we are doing the energy balance for the following systems:
Heat exchanger=1
Distillation column=2
Continuous stirred tank reactor=1
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MIXER
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1
HEAT EXCHANGER
Heat duty = 629669.37 J/sec
20
Production of Biodiesel
CSTR
DISTILLATION COLUMN 1
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SEPARATOR
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• Heat duty = -23568.13
J/sec
• Here Glycerol is
separated out
DISTILLATION COLUMN 2
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DESIGN OF SHELL AND TUBE HEAT EXCHANGER
Shell side:
• Mass flow rate of process fluid= 3.62 kg/sec
• Average cp= 2767.8 J/kg-K
• Density = 750 kg/m3
• Viscosity = 0.00252 kg/m-sec
• Thermal conductivity = 0.01375 W/m-K
• Inlet temperature = 473.15 K
• Outlet temperature = 416.85 K
Tube side:
• Mass flow rate = 2.45 kg/sec
• Cp = 1920 J/kg-K
• Density = 880 kg/m3
• Viscosity = 0.00934 kg/m-sec
• Thermal conductivity = 0.0607 W/m-K
• Inlet temperature = 300.15K
• Outlet temperature = 423.15 K
3. Assume Uo = 500
S
Ft = 0.94 (from graph 12.19,Kern)
∆Tm = ∆Tlm * Ft = 77.49 *0.74 = 57.7
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A
= 21.96 m2
5. Out Side Diameter = 19.05 mm
Internal diameter = 15.05 mm
Tube length = 3.66m
7. no of tubes = 99.32 tubes
8.Tube velocity =
= 3.17 m/s
Re = 4456.4
Pr = 294.16
1.
hi = 2190.05 w/m2k
9.ΔPt = Npass {8jf*(L/di)+2.5} ρu2/2
= 4{8*1.2*10ˉ³(3.66/15.05*10ˉ³)+2.5}*(880(3.17)2/2)
= 0.233bar
10. Db = do ( Nt / Kt )1/n
= 19.05*10ˉ³ (
=
0.287
ds
=
db
+
C
(clearance = 55mm)
=0.287+0.055 = 0.342m
lb = Ds/5 = 0.0684m
Pt = 1.25 do
= 1.25*19.05*10 = 0.0238m
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De
]
De = 0.0139 m
Nu = 0.023* Re0.8 * Pr0.33 q=
2.45* 1920 * (150-30) = ṁ* 2767.8*(200-143.7)
ṁ = 3.62 kg/sec
Q = 3.62*10¯³ m3/s
Ct = Pt – do
= 0.0238 – (19.05*10ˉ³) = 0.00475 m
Ashell = C * lb ds/Pt
= 0.0046 m2
Ũs
= 1.01 m/s
Re
Pr
baffle cut = 25% ho = 0.023* Re0.8 *
Pr ˙³³
= 0.023*(4202.40)0.8* (51.09)0.33
ho
= 1572 w/m2 k
∆Ps = 8* jf *
f=
4.1*10ˉ3
)
= 3.0 bar
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Rdo + Rdi
kw = 19 w/m k
Therefore, Uo = 470.6W/m2 K
Now
= 500 – 470.6/50
=
0.0588
= 5.8 % < 30%
Hence design is accepted.
Design of distillation column
Process design of distillation column for the separation of Bio
diesel and
methanol is given as below. Feed entering the column consist of bio diesel and
glycerol mixture. Boiling points of the compounds entering the column at
operating pressure i.e. one atmospheres.
 Bio diesel 135˚C
 Methanol 64.7 ˚C
PROCEDURE TO DESIGN THE DISTILLATION COLUMN :
1. Calculate the maximum and minimum vapour and liquid flow-rates, for the
turn down ratio required.
2. Collect, or estimate, the system physical properties.
3. Select a trial plate spacing.
4. Estimate the column diameter, based on flooding considerations.
(a) Using Actual velocity, calculate the value of volumetric flow rate
vapour, at the bottom, then find net area , column C/S area and downcomer
area and length of weir.
5. Calculate the value of perforated plate area.
6. Then find the area of distribution and calming zone (Acz).
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7. Now find out total hole area, weir height and check for weeping.
8. The check for weeping is found by estimating the values of
(a) head loss through dry hole (hd)
(b) head loss through bubble formation (hσ)
(c) height of liquid crest over weir (how)
(d) From value of (how+hw) & (Ah/Aa ) we get
(hd+hσ)min
minimum value of
(e) Now find out whether the design value is greater than theoretical value
or not.
9. Now check for down flow flooding.
10. Calculate the maximum and minimum vapour and liquid flow-rates, for the
turn down ratio required.
11. Collect, or estimate, the system physical properties.
12. Select trial plate spacing
13. Estimate the column diameter, based on flooding considerations.
14. Decide the liquid flow arrangement
15. Make a trial plate layout: downcomer area, active area, hole area, hole size,
weir height
16. Check the weeping rate if unsatisfactory return to step 6.
17. Check the plate pressure drop,if too high return to step6 18. Check downcomer
back-up, if too high return to step 6 or 3.
19. Decide plate layout details: calming zones, unperforated areas. Check hole
pitch, if unsatisfactory return to step 6.
20. Recalculate the percentage flooding based on chosen column diameter.
21. Check entrainment, if too high return to step 4
22. Optimise design: repeat steps 3 to 12 to find smallest diameter and plate
spacing acceptable (lowest cost).
23. Finalise design: draw up the plate specification and sketch the layout.
Flow parameters:
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•
Feed = 152.798 k mole/hr , Xf = 0.938
•
Distillate = 144.7 k mole/hr , Xd = 0.99
•
Residue = 8.0931 k mole/hr , Xw = 0.177
•
Column pressure = 2.08 atm
•
Feed is at its boiling point. Hence q line is vertical.
From the graph: intercept of enriching section operating line for minimum reflux
is obtained from the graph, is given by:
xD / (Rm+1) =
0.946
Rm+1= xD/ 0.946
= 0.99/ 0.946
Rm = 1.046
Let R = 1.5×Rm ; Therefore, R= 1.5×1.046 = 1.569
•
Number of Ideal trays = 12(excluding the reboiler).
•
Number of Ideal trays in Enriching Section = 4
•
Number of Ideal trays in Stripping Section = 8 Design of enriching
section:
Tray spacing (ts) :
• let ts = 18 ” = 457 mm (range 0.15 – 1.0 m)
hole diameter (dh) :
• let dh = 5 mm (range 2.5 to 12 mm)
Hole pitch (lp) :
• let lp = 3 * dh (range 2.5 to 4.0 times dh)
i.e., lp = 3 * 5 = 15 mm
Tray thickness (tT ) :
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• (tT ) = 0.6 * (dh ) = 3 mm (range 0.4 to 0.7 times dh )
Ratio of hole to perforated area (Ah / Ap ) :
• (Ah/Ap) = ½ (π/4×dh2)/ [(√3/4) ×lp2]
= 0.1
Plate diameter (Dc):
• The plate diameter is calculated based on entrainment flooding
considerations
• L/G {ρg/ρl}0.5 = 0.004
---------- (maximum value)
(From fig. 18.10 p-18-7 Perry hand book 6th edition)
• L/G {ρg/ρl}0.5 = 0.004 and for a tray spacing of 500 mm.
• From the flooding curve………….Flooding parameter,
Csb, flood = 0.29 ft/s
• Unf = Csb, flood × (σ / 20) 0.2 [(ρl - ρg) / ρg]0.5
(From eqn. 18.2, page 18.6, 6th edition Perry hand book) where,
Unf
flood
σ
= gas velocity through the net area at flood, m/s (ft/s) Csb,
= capacity parameter, m/s
= liquid surface tension, mN/m
(dyne/cm.) ρl
ρg
= liquid density, kg/m3 (lb/ft3)
= gas density, kg/m3 (lb/ft3)
Unf = 1.325 m/
Actual velocity, Un= 0.8×Unf
Un = 1.06 m/s
Volumetric flow rate of Vapour at the bottom of the Enriching Section
qo = 0.554 m3/s
Net area available for gas flow (An):
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Net area = (Column cross sectional area) - (Down comer area.)
An = Ac - Ad
Net Active area,
An = qo/ Un = 0.554/ 1.06 = 0.522m2
Let Lw / Dc = 0.77 (range of 0.6 to 0.85 times Dc)
Where, Lw = weir length, m
Dc = Column diameter, m
Now,
θc = 2×sin-1(Lw / Dc) = 2×sin-1 (0.77) = 100.70
Ac = (π/4) * Dc 2 = 0.785 * Dc 2 m2
Ad = [(π/4) × Dc2 × (θc/3600)] - [(Lw/2) × (Dc/2) ×cos (θc/2)] Therefore
DC = 0.87 m.
Perforated plate area (Ap) :
Ap = Ac - 2Ad
= 0.4496 m2
Acz = 2 * Lw * (thickness of distribution)
Area of calming zone, m2 (5 to 20% of AC)
Awz = 2*{(π/4)*Dc2 * (θc / 360˚) – (π/4) * (Dc – 30 * 10-3)2 * (θc /360˚) }
Area of waste periphery,m2(range 2 tp 5 % of Ac)
AP= Ac -2Ad - Acz - Awz
Ap = 0.387 m2
Total hole area (Ah) :
Ah / Ap = 0.1
Ah = 0.1 * Ap
Ah = 0.0387 m2
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Now we know that , Ah = nh × (π/4) * dh2
nt = number of holes = 1971 Weir height (hw) :
let hw = 50 mm
Weeping check:
• Head loss through dry hole
• Head loss due to bubble formation
• Height of liquid crest over weir
• Down comer flooding
• Head loss over down comer apron
Head loss through dry hole : hd = head loss across the
dry hole = k1 + k2 (ρg/ρl) Uh2
Where,
Uh is gas velocity through hole area
K1 and K2 are constants
From sieve plates,
K1 = 0 and
K2 = 50.8/cv2
Where cv is discharge coefficient
(Ah/Aa) = 0.086 and ratio of tray thickness to hole diameter tT/dh = 0.60
For above values of (Ah/Aa) and tT/dh ,( from fig. edition 18.14, page 18.9 6th Perry)
We get
Cv (discharge coefficient) = 0.74
And hence, k2 = 50.8 / 0.742 =
92.77
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Volumetric flow rate of Vapour at the top of the Enriching Section
qt = 0.5514 m3/s -------- (minimum at top) Volumetric flow rate of Vapour at the
bottom of the Enriching Section qo = 0.554 m3/s. ---- (maximum at bottom)
Velocity through the hole area (Uh):
Velocity through the hole area at the top =
Uh, top = qt /Ah = 0.5514/0.0387= 14.25 m/s
Velocity through the hole area at the bottom= Uh, bottom = qo /Ah
= 14.31 m/s
hd, top = k2 [ρg/ρl] (Uh,top)2
= 92.77×(3.4376/784.69) * 14.252
= 82.526 mm clear liquid. -------- (minimum at top)
hd, bottom = k2 [ρg/ρl] (Uh, bottom)2
= 92.77×(3.425/784.50) ×14.312
= 82.94 mm clear liquid ----- (maximum at bottom)
Head loss due to bubble formation :
hσ = 409 [ σ / ( ρL
* dh) ]
where σ =surface tension (mN/m)
dh =Hole diameter, mm hσ = 409
[ 19.325 / ( 784.69 x 5)] hσ =
2.014 mm clear liquid Height of
liquid crest over weir :
how = 664Fw [(q/Lw)2/3]
q = liquid flow rate at top = 0.009 m3/min
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Fw= correction factor = 1.03 Lw= weir length
= 0.67m how= 2.520 mm clear
liquid hd + hσ = 82.526 + 2.014 = 84.54 mm ----------design value hd + how =
50 + 2.52 = 52.52 mm since the design value is greater the minimum value, there
is no problem of weeping.
Down comer flooding :
hds = hw + how + hhg /2 -------(eqn 18.10, page 18.10, 6th edition perry)
Where hw = weir height
hds = static slot seal
clear liquid, mm
how = height of crest over weir, equivalent
hhg = hydraulic gradient across the plate, height of
equivalent clear liquid
hds = 52.77 mm
 Head loss over down comer apron :
hda = 165.2 {q/ Ada}2
Take clearance, C = 0.5” hap
= hds - C = 52.77 – 25.4 = 27.37 mm
Ada
= Lw x hap = 0.0183 m2
hda =
165.2[1.6061 * 10-4/ 0.0183] 2
= 0.0127 mm
ht = hd + hl` = 82.94+31.662 = 114.602 mm
Hdc (height of down comer) = ht+ hw + how + hda + hhg
=114.602 + 50 + 2.52 + 0.0132 + 0.0127
= 167.148 mm
h`dc = hdc / φ , where φ is the froth density.
= 167.148/ 0.5 = 334.29 mm which is less then the tray spacing , t s = 457 mm
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Summary of the distillation column
Enriching section
Stripping section
Tray spacing
457 mm
457 mm
Column diameter
0.87 m
0.94 m
Weir length
0.67 m
0.724 m
Weir height
50 mm
50 mm
Hole diameter
5 mm
5 mm
Hole pitch
15 mm
15 mm
Tray thickness
3 mm
3 mm
Number of holes
1971
2308
Flooding %
80
80
COST ESTIMATION
An acceptance plant design must present a process that is capable of
operating of operating conditions which will yield a profit. Since net profit equal
to income all expenses,it is essential that a design engineer be aware of many
different types of cost involved in manufacturing process. Capital must be
allocated for different plant expenses, such as those for raw materials, labour and
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equipment . beside direct expenses many other indirect expenses are incurred and
these must be included. If a complete analysis of the total cost is to be obtained.
Some examples of these indirect expenses are administrative salaries, product
distribution costs and cost for inter plant communication .
A capital investment is required for any industrial process and
determination of the necessary. Investment is an important part of the plant design
. The total investment for any process consists of the fixed capital investment for
physical equipment and fecilities in the plant plus working capital which must be
available to pay salaries keep raw materials and products on hand and handle other
special items requiring direct cash out lay. Thus in an analysis of costs and general
expenses including income tax must be taken into consideration. Cost estimation
in industrial process is made for a number of reasons such as
• To enable feasible studies to be carried out
• To enable selection from alternative sources of environments
• To assist in selection from alternative design
• To provide information for planning the appropriate of capital.
• To enable the contracts to tenders for the new project.
The first in the preparation of a cost estimate both the capital
investment and for manufacturing or operating cost is to prepare a process
flow sheet showing all major items of the equipment including the flow
lines and instrumentation. Heat and material balances have to be compared
so that the temperature and pressure and composition of stream will be
known.
The next step is to calculate the size and geometry of the
equipment and to specify the material of the construction. Then a
preliminary cost estimation is made for the capital investment based on the
a.)The purchased cost of all equipment as shown in the flow sheet
b.)The manufacturing cost of the product from the material and energy
balances
c.)The cost of raw materials , utilities, labor and depreciation.
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1.) PURCHASED EQUIPMENT COST (PEC)
Equipment
Cost per
Number of units
unit(crores)
Total cost
Reactor
2.15
1
2.15
Mixer
0.221
2
0.442
Heat exchanger
1.29
1
1.29
Pump
0.516
1
0.516
Distillation column
4.3
2
8.6
Decanter
0.645
1
0.645
8
13.643
Total
2.) INSTALLATION COST INCLUDING INSULATION AND PAINTLNG::
10-15%OF PEC
Consider installation cost =15%PEC
=0.15*(13.643)=1.98 Crores.
3.) INSTRUMENTATION AND CONTROLLS INSTALLED:
50-70%PEC
Consider instrumentation cost=60% PEC=0.6*PEC=7.92 Crores.
4.) PIPING INSTALLED:
25-50% OF PEC
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Assume 45%.
Piping cost= (0.45)*PEC=5.94 Crores.
5.) INSTALLATION COST:
10-40% OF PEC
Assume 15%
Electrical cost=15% of PEC=1.98 Crores.
6.) BUILDINGS PROCESS AND AUXILLARY::
10-70% of PEC
Assume 45%.
Considerable process and auxiliary cost=0.45*PEC=5.94 Crores.
7.) SERVICE FECILITIES:
30-80% OF PEC
Assume 55%
Service facilitate cost=(0.55)*PEC=7.26 Crores.
8.) LAND:
20% OF PEC
Land cost = (0.2*PEC) =2.64Crores.
9.) YARD IMPROVEMENT:
10-20% OF PEC.
Assume 12%.
Yard cost=1.58 Crores.
10.) TECHNOLOGY AND ENGINEERING FIELD:
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20% OF PEC
Cost =2.64 Crores.
Total direct cost=51.08 Crores.
INDIRECT COST
A.)ENGINEERING AND SUPERVISION:
15-35 OF DC (direct cost)
Assume 25%
Cost = (0.5*DC) =12.77 Crores.
B.)CONSTRUCTION EXPENSES AND CONTRACTORS FEE (CEC):
34% OF DC
CEC=O.34*DC=17.36 Crores. C.)CONTINGENCY:
8-20% OF DC
Assume 15%.
Contingency cost= (0.15*DC) =7.66 Crores.
Total indirect cost=37.80 Crores.
FIXED CAPITAL INVESTMENT (FCI)
FCI=DC+IDC
=51.08+37.80
=88.89 Crores.
WORKING CAPITAL INVESTMENT (WCI)
10-20% of FCI
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Assume 15%
WCI=13.33 Crores.
TOTAL CAPITAL INVESTMENT (TCI)
TCI=WCI+FCI=13.33+88.89 = 102.22 Crores.
ESTIMATION OF TOTAL PRODUCT COST
Total product cost=Manufacturing cost + General expenses
Manufacturing cost=Fixed charges + direct production cost +Plant overhead cost.
1.) FIXED CHARGES
A.)DEPRICIATION
10% OF FCI
Depreciation =8.88 Crores.
B.)LOCAL TAXES
3-4% 0F FCI
Local taxes=0.03*FCI=2.67 Crores.
C.)INSURANCE
1% OF FCI
INSURANCE=0.888 Crores.
Total fixed charges=12.44 Crores.
But Fixed charges=15% of TPC.
TPC=82.96 Crores.
2) DIRECT PRODUCT COST:
A.)RAW MATERIALS
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10-40% of TPC
Raw material cost=24.88 Crores.
B.)OPERATING LABOUR
10-20 % OF TPC.
Assume 15%
OLC=12.44 Crores.
C.)DIRECT SUPERVISORY AND CLINICAL LABOUR (DS&CL)::
DS&CL=20% OF OPERATING LABOUR=2.488 Crores.
D.)UTILITIES
10-20% OF TPC.
Assume 15%.
Utilities cost=12.44 Crores.
E.)MAINTENANCE AND REPAIRS
2-10% OF FCI Assume
6%.
Cost =5.33 Crores.
F.)OPERATING SUPPLIES
15% of Maintenance cost.
Cost=0.80 Crores.
G.)LABOURATORY CHARGES
10-20% of operating labor cost.
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Assume 15%.
Cost=1.86 Crores.
H.)PATENT &ROYALTIES
2-6% OF TPC.
Assume 4%.
COST=3.32 Crores.
Total direct production cost= 63.54Crores.
PLANT OVER HEAD COST
50-70% of Operating labor, supervisory, maintenance.
Assume 60%.
COST=12.16 Crores.
TOTAL MANUFACTURING COST=FC+DPC+POC=88.19 Crores.
GENERAL EXPENSES
A.)Administration cost
COST= 25%of OL =3.11Crores.
B.)Distribution and marketing cost
DMC=2-20% OF TDPC= 11.76 Crores.
C.)Research and development cost
3% OF TDPC.
RDC=1.90Crores.
General expenses=ACC+DMC+RDC= 16.54 Crores.
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TOTAL PRODUCTION COST=MC+GE=104.97 Crores. GROSS
EARNINGS/INCOME & RATE OF RETURN
Number of operating days in a year =330 days.
Cost of Biodiesel = Rs 42.47 per Kg.
Total annual sales=182.35 Crores.
Gross profit= 182.35-104.97=77.37 Crores.
Assume tax to be 35%
Net profit=Gross profit*(1-tax) = 27.08 Crores.
Rate of return=Net profit / (Total sales)*100=14.85%.
Pay out period=TCI / (NET PROFIT+DEPRICIATION) = 2.84 Years.
Break even analysis:
Total variable cost = TDC+PDC+GE
= 78.09
At the breakeven point FC+TVC = Net sales
Total capacity for an year = 1000 tons per year
PLANT LOCATION AND LAYOUT
The success of an industrial venture greatly depends on geographical location of
the plant. Enough care must be exercised in selecting the plant site and different
factors must be considered before finalizing the plant location. The plant should
be located where the minimum cost of production and distribution can be
obtained, also keeping in view other factors, such as room for expansion, safe
living conditions for plant operating people and the surrounding community,
which is also important. Consciences regarding plant location should be obtained
before a design project reaches detailed estimate stage and firm location should
be established upon completion of detailed design.
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The choice of final site should be based on complete survey advantages and
disadvantages of various geographical areas and, ultimately, on the advantages
and disadvantages of available real estate.
The source of raw material is one of the most important factors influencing the
location of the plant site because location near the raw materials source permits
considerable reduction in transportation and storage charges. Proximity to major
markets is one important consideration in selection of plant site. It should be noted
that markets are needed for by-products as well as for major final products. Power
and fuel can be combined as another major factor in the choice of a plant site as
their requirements are high in most of the industrial plants. A location near a
source of fuel supply or large hydroelectric installations may be essential for
economic operations.
The plant site should have access to all types of transportation; certainly two types
should be available. The proximity to rail road centers and possibility of canal,
river, lake or oceans transport must be considered. The kind and amount of
products and raw materials determine the most suitable type of transportation
facilities. Attention should be paid to local freight rates and existing road lines.
Climate is a factor that should be examined when selecting a plant site. Improper
selection can have serious effect on the economic operation of a plant. The
process industries use large quantities of water for cooling, washing, steam
generation and as a raw material. The plant therefore must be located where a
dependable supply of water is available. The temperature, mineral content silt or
sand content, bacteriological content and cost for supply and purification
treatment must also be considered while choosing the water supply. The site
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selected for a plant should have adequate capacity and facilities for waste water
disposal.
The permissible tolerance levels for various methods of waste disposal should
be consider carefully and potential requirements for additional waste treatment
facilities should be consider, even though a given area has minimal restrictions
on pollution.
Type and supply of skilled and unskilled work force available in the vicinity of
proposed plant should be examined. Similarity state and local tax rates on
property income, unemployed insurance, local regulations on zoning, building
codes, nuisance aspects and transportation facilities have a major influence on the
final choice of plant site.
Considering all the above factors and keeping in view the latest development
trends, storage facilities for raw materials and intermediate and finished products
may be located, in isolated areas or in adjoining areas. The plant can be located
near any refinery such as MRPL, IOCL, OR IPCL. As water needed in large
quantity, the site near river will be quite feasible as water can be obtained from
it.
Plant layout involves the layout of process units in a plant and the equipment
within these process units. The layout can play an important parting determining
construction and manufacturing costs and thus be planned carefully with the
attention being gives to future problems that may arise. Plant layout means the
disposition of the various equipment’s, material and man power etc., and services
of the plant within the area of the site selected previously. The plant layout begins
with the design of the factory building and goes up to the location and movement
of the work table. All the facilities like equipment’s, raw materials, machinery,
tools, fixtures workers etc., are given a proper place. Rational design must include
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arrangement of processing areas, storage areas and handling areas in efficient coordination and with regards to such factors as
1. New site development or addition to a previously developed site.
2. Future expansion.
3. Economic distribution of services- water, process steams, power and gas.
4. Weather condition.
5. Safety consideration- possible hazards of fire, explosion and fumes.
6. Building code requirements.
7. Waste disposal problems.
8. Sensible use of floor and elevation space.
Principles of plant layout:
a. Integration:
It means the integration of production Centre facilities like workers, machinery,
raw materials etc., in a logical and balanced manner.
b. Minimum movements and material handling:
A few sound principals of plant layout have been brief as under, they are the
principles number of movements of workers and materials should be minimized.
It is better to transport materials in optimum bulk rather than in small amounts.
c. Smooth and continuous flow:
Bottle necks, congestion points and back tracking should be removed by proper
line balancing techniques.
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d. Cubic space utilization:
Besides using the floor space of the room, the ceiling height is also to be utilized,
so that more materials can be accommodated in the same room.
Overhead material handling equipments save a lot of valuable floor space.
e. Safe and improved environment:
Working places-safe, well ventilated and free from dust, noise, fumes, odours
and other hazardous conditions decidedly increases the operating efficiency of
the workers and improve their moral. All this leads to satisfaction amongst the
workers and thus better employer employee relations.
f. Flexibility:
In automotive and other industries where models of products change after some
time, it is better to permit all possible flexibility in the layout. The machinery is
arranged in such a way that charges of the production process can be achieved at
the least cost of disturbance.
g. Storage facilities and raw materials:
Intermediates and finished products may be located in isolated areas or in
adjoining areas. Hazardous materials stored in the large quantities should be
isolated. Arranging storage of materials so as to facilitate or simplify handling is
also a point to be considered in design.
h. Economy of floor space:
Consistent with good housekeeping in the plant with proper considerations
given to line of flow of materials, access to materials, space to permit working on
parts of equipment that needed frequent servicing and safety and comfort of the
operations. It is fundamental in chemical engineering industries that the buildings
should be around the process instead of process being made to fit in buildings of
Production of Biodiesel
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conventional design of a new building to meet the requirements of the process is
more scientific.
i. Labour supply:
Skilled and unskilled labour is obtained in Indian states. The villagers near the
sites can accommodate for enough of unskilled labour and all the engineering
graduates of colleges can form the skilled labour.
j. Market:
This is one of the major declining factors of plant location and in this respect
the plant should be near a big city, which should be a major trade centre so that a
lot of money can be saved on transportation charges and final product will have
a heavy demand.
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ENGINEERING PROBLEMS AND SAFETY CONSIDERATIONS
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ENGINEERING PROBLEMS:
Engineering problems in hydrolysis of organic compounds is that organic
compounds, being stable compounds, require relatively high reaction
temperatures. However, once reaction has started, the intermediate products are
much less stable and the reaction tends to drive temperatures out of control.
Direct oxidation of organic compounds is carried out commercially by vapour
phase and liquid phase processes, the liquid phase processes are practiced at
somewhat lower temperatures and therefore sophisticated systems.
SAFETY CONSIDERATIONS:
There is every incentive and a real necessity foe including a survey of safety and
fire hazards in a study of chemical engineering processes. Some of the important
safety considerations in the chemical industries where toxic substances are
manufactured, handled or used are summarized here. Suitable services should be
installed where ever possible to give warning in case of liberation quantities of
these substances. Every operation or process involving use of irritating and the
packing of the product should be effected by mechanical means is apparatus
provided with adequate enclosures and dust collecting systems in order to curtail
atmospheric contamination. Any spillage of irritating or toxic dry compounds
should be removed as quickly as possible, preferably by vacuum apparatus.
All personnel exposed to toxic substances should be provided overalls or
working clothing and also a time allowance of not less than 10 minutes at the
expense of the employer for the use of baths at the end of days’ work.
One or more aid tips or cabinets, containing sufficient and suitable first aid
dressing and other equipment should be provided and maintained in easily
available locations for immediate temporary treatment in case of accident or
sudden illness.
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In addition to chemical hazards, mechanical hazards, electrical hazards are also
to be dealt with by recognizing and incorporating with minimum safe practices
prescribed by nationally recognized protection associations, engineering
authorities and government bodies. Fire prevention and control, good ventilation
systems are also indubitably important aspects to be considered for the safe and
successful operation of chemical process industries.
Measures to prevent and control circumstances which produce fatigue, such as
excessive noise, inadequate ventilation, poor lighting, excessive heat and
humidity, to the workers are to be taken. Sanitation in the plant should also be
taken into consideration. Safety must be considered when dealing with disposal
of wastes as effecting persons outside the jurisdiction of the plants. All the
personnel should be thoroughly informed of the hazards connected with their
duties and the measures to be taken to protect themselves there from.
The management should take special responsibility of those who have placed
their health, welfare and livelihood in their hands, to invite a sense of security, as
safety hazards and potential deterrents to attainment of optimum technical
efficiencies and product quality. No matter highly satisfactory a plant design may
be from the technical and economic view point, disregard of safety, air pollutions
and disposal problems will nullify an otherwise sound engineering plant design.
POLLUTION CONTROL AND SAFETY
The effluent from Nicotinamide plant consists of mainly blow downs of
condensers, cooler and condensates from distillation column. These may contain
negligible amount of Nicotinamide.
STORAGE & HANDLING
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Keep in a tightly closed container. Store in a cool, dry ventilated area from
sources of ignition. Protect against physical damage. Store separately from source
of heat or ignition. Protect against physical damage. Store separately from
reactive or combustible materials and out of direct sun light. Avoid dust formation
and control ignition sources. Employ grounding venting and explosion relief
provision in accord with accepted engineering practices in any process capable of
generating dust and or static electricity. Empty only in to inert or non-flammable
atmosphere. Emptying contents into a non inert atmosphere where flammable
vapours may be present could cause flash fire or explosion due to electrostatic
discharge. All workers should be properly trained on its hazards and the proper
protective measure required. This training should also include emergency actions.
All product operations should be enclosure to eliminate any potential exposure
routes. Containers of this material may be hazardous when empty since they
retrain product residue observe all warnings and precaution listed for the product.
EXPOSURE CONTROL/PERSONAL PRODUCTION
Airborne exposure limits
OSHA Permissible Exposure limit (PEL)
ACGIH Threshold limit value (TLV)
VENTILATION SYSTEM:
5ppm (TWA) (skin)
5ppm
(TWA)
(skin)
A system of local is generally preferred because it can control the emission of
the contaminant at its source, preventing dispersion of it into the general work
area. Please refer to the ACGIH document, Industrial ventilation manual of
recommended practices most recent edition for details.
PERSONAL RESPIRATORS (NIOSH APPROVED):
If the exposure limit is exceeded a full face piece respirator with organic vapour
cartridge and dust/mist filter may be worn up to 50 times the exposure limit or
the maximum use concentration specified by the appropriate regulatory agency
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or respirator supplier whichever is lowest. For emergencies or instance where the
exposure levels are not known use a full face piece positive pressure air supplied
respirator.
SKIN PROTECTION:
Wear impervious protective clothing including boots, gloves, lab coat, apron or
coveralls to prevent skin contact. Butyl rubber and neoprene are suitable materials
for personal protective equipment.
EYE PROTECTION:
Use chemical safety goggles and or full face shield where dusting or splashing of
solution is possible. Maintain eye wash fountain and quick-drench facilities in
work area.
BIBLIOGRAPHY:
1) Biodiesel production,Transesterification of Vegetable Oil and Methanol ,David
Houghton, Desirée LeBlanc, Michael Thiessen.
2) Dhar, B., & Kirtania, K. (2009). Excess Methanol Recovery in Biodiesel Production
Process Using a Distillation Column: A Simulation Study. Chemical Engineering
Research Bulletin, V.13 No.2.
3) Hillion, G., Delfort, B., le Pennec, D., Bournay, L., & Chodorge, J.-A. (2003).
Biodiesel Production By A Continuous Process Using a Heterogenous Catalyst.
France: Institut Français du Pétrole.
4) Leazer, J. (2013). Transforming Paper Mill Pollution into Commercial Resource.
United States Environmental Protection Agency: Science Matters Newsletter.
5) MacLeod, R. (2009). Waste Vegetable Oil Survey Report. Sault Ste. Marie: Science
Enterprise Algoma.
Production of Biodiesel
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