formaldehyde production from methanol
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McMaster University 6 December, 2010 1280 Main Street West Hamilton, ON L8S 4L9
To: Mr. Matthew Hazaras From: Group 4 (G. Leota, J. Ma, H. Park, S. Park, G. Voloshenko) Subject: SDL Project
Dear Mr. Matthew Hazaras, As requested in the Engineering Economics and Problem Solving class, please find attached the final version of the formaldehyde plant report. The report studies the production of formaldehyde from methanol using a silver catalyst, and includes an overview of typical plant setup and operation, as well as sections on safety and troubleshooting. The economic aspects of running such a plant are also considered. The production of formaldehyde is a straightforward process. Methanol and air are combusted within a reactor in the presence of a silver catalyst. The product is a mixture of formaldehyde and methanol in water, which is then run through an absorber to remove inert gases and a distillation column to recycle residual methanol. The final product contains approximately thirty-seven weight percent formaldehyde in water with four weight percent methanol added as a stabilizer. The formalin solution may then be stored or used immediately in another application. Due to the health risks posed by working with formaldehyde and methanol, our proposed improvements to the process are the addition of a rupture disk to the methanol vaporizer and implementation of hermetically sealed canned pumps along points in the process handling formaldehyde. This will reduce the likelihood of leaks along the process, and therefore reduce exposure to these hazardous chemicals and lower their emissions from the plant. Sincerely, G. Leota J. Ma H. Park S. Park G.Voloshenko
CHEM ENG 4N04 Group 4
Final Report
G. Leota
J. Ma
H.Park
S. Park
G. Voloshenko
Dr. P. Mhaskar
December 6, 2010
Formaldehyde Production from Methanol
CONTENTS
1. Introduction .................................................................................................................................. 1
2. Process Overview ........................................................................................................................ 1
2.1. Formaldehyde ....................................................................................................................... 1
2.1.1. Physical and Chemical Properties ................................................................................. 2
2.1.2. Applications and Benefits of Formaldehyde ................................................................... 2
2.1.3. Formaldehyde Production in Canada ............................................................................. 2
2.2. P&ID Description ................................................................................................................... 3
3. Process Principles ....................................................................................................................... 4
3.1. The Feed Stream .................................................................................................................. 4
3.2. The Reactor Configuration .................................................................................................... 4
3.3. Separation Process ............................................................................................................... 5
3.3.1. The Absorber .................................................................................................................. 5
3.3.2. The Distillation Column .................................................................................................. 5
3.4. Storage .................................................................................................................................. 6
4. Operability .................................................................................................................................... 6
4.1. Operating Window ................................................................................................................ 6
4.2. Flexibility ............................................................................................................................... 8
4.3. Reliability ............................................................................................................................... 9
4.4. Efficiency ............................................................................................................................. 10
4.4.1. Equipment Capacity ..................................................................................................... 10
4.4.2. Equipment Technology................................................................................................. 11
4.4.3. Equipment Utilization.................................................................................................... 11
4.4.4. Process Structure ......................................................................................................... 11
4.4.5. Operating Conditions.................................................................................................... 12
4.4.6. Calculation of Efficiency ............................................................................................... 12
4.5. Transition ............................................................................................................................ 12
4.5.1. Start Up ........................................................................................................................ 12
4.5.2. Shut Down .................................................................................................................... 13
5. Troubleshooting ......................................................................................................................... 13
6. Health and Safety Aspect .......................................................................................................... 13
6.1. Material Safety .................................................................................................................... 14
6.2. Process Safety .................................................................................................................... 14
7. Economics ................................................................................................................................. 15
7.1. Relevant Issues .................................................................................................................. 15
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7.1.1. Methanol Price ............................................................................................................. 15
7.1.2. Ontario’s new Smart Meter policy ................................................................................ 16
7.1.3. Housing Market Crisis in 2007 ..................................................................................... 16
7.2. Capital Cost Estimation ....................................................................................................... 17
7.3. Operating Cost Estimation .................................................................................................. 18
7.3.1. Using Ontario’s Smart Rate ......................................................................................... 19
8. Process Recommendations ....................................................................................................... 19
9. Conclusions ............................................................................................................................... 20
References .................................................................................................................................... 22
Appendix ........................................................................................................................................ 24
Appendix A- Sample Efficiency Calculations ............................................................................. 24
Appendix B- Troubleshooting Fishbone Diagram and Table ..................................................... 25
Appendix C - HAZOP ................................................................................................................. 26
Appendix D - MSDS of Formaldehyde and Methanol ................................................................ 29
Appendix E –Capital & Operating Cost Calculation ................................................................... 34
Tables
Table 1 List of alarm sign under possible system failure .............................................................. 14
Table 2 Hydro cost calculated via original rate, summer and winter Smart rate ........................... 19
Table B 1 High temperature of reactor causes and solutions ....................................................... 25
Table D 1 MSDS of Formaldehyde ................................................................................................ 29
Table D 2 MSDS of Methanol ........................................................................................................ 31
Table E 1 Capital Cost Table ......................................................................................................... 34
Table E 2 Operating Cost Table .................................................................................................... 35
Table E 3 Net present value calculations ...................................................................................... 36
Figures Figure 1. Formaldehyde production from methanol P&ID ............................................................... 3
Figure 2. Process flow diagram of the reactor ................................................................................. 4
Figure 3 Operating window of reactor with air flow rate vs. methanol flow rate (kmol/h) ................ 7
Figure 4 Historic methanol price from 2006 to 2010 [13] .............................................................. 16
Figure 5 Ontario's Smart Electricity Cost ....................................................................................... 16
Figure 6 Standard & Poor's Case-Shiffer home price index [15] .................................................. 17
Figure 7 Operating cost distribution............................................................................................... 19
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1. INTRODUCTION
Chemical manufacturers around the globe do careful analyses from many
perspectives prior to launching a new project. Starting from the basic background
research, to the market analysis, and finally to plant safety, multi-faceted and in-
depth research must be performed. Engineers perform crucial roles in this
process. They make sure the company maximizes profit from the operation while
keeping safety paramount.
Formaldehyde is a key chemical component in many manufacturing
processes. It is relatively simple to produce, although careful handling,
transportation and storage are required. In this report, analyses on the chemical
itself, reactions, safety, plant design, troubleshooting and economics were
performed. Finally, some conclusions and suggestions were presented.
2. PROCESS OVERVIEW
2.1. FORMALDEHYDE
Formaldehyde (CH2O) is known as the first series of aliphatic aldehydes.
The occurrence of formaldehyde is abundant in air and is also a byproduct of
several biological processes. The average person produces 1.5 ounces of
formaldehyde per day as part of normal human metabolism [1]. Plants and
animals produce formaldehyde as their byproducts. For example, Brussels
sprouts and cabbage emit formaldehyde when they are cooked [2].
Formaldehyde can be produced by oxidation of methanol with air in the
presence of catalyst. Formaldehyde may be produced at a relatively low cost,
high purity, and from a variety of chemical reactions, making formaldehyde one
of the most produced industrial chemicals in the world. Formaldehyde industries
have been grown since 1972, from a yearly global production volume of 7 million
metric tons up to 24 million metric tons in recent years [3]. In addition,
commercial uses of formaldehyde have widespread industrial applications, which
showcase how important the chemical is in our everyday lives.
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2.1.1. PHYSICAL AND CHEMICAL PROPERTIES
Formaldehyde has a colorless and distinctive pungent smell even can be
detected in low concentrations. It is a highly flammable gas, with a flashpoint of
50°C. The heat of combustion is 134.l kcal/mol or 4.47kcal/g [4]. Formaldehyde is
soluble in a variety of solvents and miscible in water [4]. Formaldehyde usually
sold as 37 weight percent solution in water known as formalin.
2.1.2. APPLICATIONS AND BENEFITS OF FORMALDEHYDE
Because of its unique properties, formaldehyde has been used in all
kinds of products such as vaccines, medicines, fertilizers, carpets, plastics,
clothing, glues, x-rays, and plywood [2]. Most formaldehyde products find uses
as adhesives and wood coatings to provide weather-resistance [1].
Formaldehyde is an important ingredient in production of formaldehyde-
based material. The formaldehyde-based resins are used in production of glues
for household furnishing. The largest use of formaldehyde is in the manufacturing
of amino and phenolic resins. The phenolic molding resins are used in
appliances, electrical control, telephone and wiring devices [2]. In the automotive
and building industries, formaldehyde-based acetal resins are used in the
electrical system, transmission, engine block, door panels, and brake shoes [3].
2.1.3. FORMALDEHYDE PRODUCTION IN CANADA
Today, there are six companies in Canada that make formaldehyde at 11
different locations in five provinces. For the maximum cost effectiveness,
formaldehyde is made near the point of consumption. By capacity, Borden
Chemical is the largest producer in Canada, followed by Dynea Canada Ltd,
Celanese Canada, and ARC Resin Corp. Borden Chemical is also the largest
U.S. formaldehyde producer [1].
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2.2. P&ID DESCRIPTION
As it shown in the Figure 1, the process of formaldehyde production
began with methanol and air mixture is to the reactor. Mixture is converted into
formaldehyde in the presence of a silver catalyst.
Figure 1. Formaldehyde production from methanol P&ID
Following the reactor contains a heat exchanger which contains water to
remove heat evolved from the reaction. The steam formed within the heat
exchanger is used as a heat source for the methanol vaporizer and the distillation
column. The formalin concentration is adjusted by regulating the water flow rate
into the absorber. The bottoms product from the absorber contains formaldehyde
and residual methanol, which is then sent to the distillation column. In the
distillation column, the formaldehyde is purified to a desired formaldehyde
concentration, after which it is sent to storage.
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3. PROCESS PRINCIPLES
3.1. THE FEED STREAM
The feed to the reactor contains a compressed and vaporized mixture of
methanol in air. Both the air and methanol must be free of trace impurities such
as sulphur compounds and transition-based metals, which will poison the catalyst
and decrease its lifetime [5]. As the methanol enters the process as a liquid,
compression is achieved using a pump, while the air is compressed as well.
Both streams are independently heated using pressurized steam prior to being
mixed. To reach the upper explosive limit of methanol, a composition above 37
mole percent methanol in air is used to ensure optimal combustion [6].
3.2. THE REACTOR CONFIGURATION
Figure 2. Process flow diagram of the reactor
As it shown in Figure 2, the feed enters and is immediately combusted,
resulting in reactor temperatures between 630 and 700oC. Aided by the silver
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catalyst, the oxidation-dehydration reaction proceeds along the following two
pathways:
CH3OH + ½O2 → HCHO + H2O ΔHRXN = -156 kJ/mole (1)
CH3OH → HCHO + H2 ΔHRXN = 85.0 kJ/mole (2)
The reaction converts 71 percent of the methanol into formaldehyde. The
reactor is configured to take advantage of the heat released from the reaction:
the catalyst, in the form of wire gauze, is suspended directly above a heat
exchanger tube bank [6]. The heat exchanger runs water, which is converted
into medium pressure steam and then run through the methanol vaporizer. The
heat exchanger cools the formaldehyde product to 100oC, preventing the
formaldehyde from decomposing into carbon monoxide and hydrogen. The
product stream contains inert gases, and a water, methanol and formaldehyde
vapour [6].
3.3. SEPARATION PROCESS
3.3.1. THE ABSORBER
The absorber functions to absorb any formaldehyde vapour from the reactor
product stream and removing any inert or unreacted gases. The column
contains 10 trays, each of which is 30 percent efficient [6]. Due to the high
water solubility of formaldehyde and methanol, 33 mole percent formaldehyde
and a 4 mole percent methanol solution is produced. Nitrogen and trace
amounts of formaldehyde and methanol are purged in the off-gas stream. The
product is sent to the distillation column for further removal of methanol to meet
product specifications [6].
3.3.2. THE DISTILLATION COLUMN
The distillation column removes the remaining 29% of the methanol that
was not combusted in the reactor, as well as reducing the concentration of
methanol in the formalin to meet application specifications. The column
contains 30 trays as well as a reboiler and partial condenser. The tops product
contains 99 percent methanol, which is recycled and mixed with the methanol
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feed prior to pumping. The bottoms products contain formalin, which exits
containing 1 weight percent methanol, and is subsequently sent to storage [6].
3.4. STORAGE
Formalin storage is made difficult as the formation of formaldehyde
dimers and trimers, known as paraformaldehyde, occurs at temperatures below
25oC, while the formation of formic acid is favoured at temperatures above 25oC
[7]. Both materials are impurities and reduce the quality of the final formalin
product. In dilute quantities, methanol may be used to inhibit the degree of
polymerization of formalin, with 1 weight percent methanol typically used.
Storage at temperatures between 35 and 45oC further inhibits the formation of
formaldehyde polymers [4].
Formic acid is readily formed when formaldehyde vapours are oxidized by
atmospheric oxygen. The extent of acid formation may be reduced by storing
the formalin under an inert gas blanket.
4. OPERABILITY
4.1. OPERATING WINDOW
The operating window for the feed mixture to formaldehyde reactor is
shown below in Figure 3, which contains variables of methanol flow rate and air
flow rate in kmol/h. The flammability limit for methanol in air is between 6 and 36
mole percent. The feed ratio to the reactor is based on the product composition
requirement, though this is typically above the upper flammability limit to ensure
maximum methanol combustion.
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Figure 3 Operating window of reactor with air flow rate vs. methanol flow rate (kmol/h)
The red solid boundary and orange boundary represent hard constraints that
cannot exist in the process. The red solid boundary corresponds to the lowest
ratio requirement, 36 mol percent methanol in air; where the red dash line (37
mol percent methanol in air) is the upper combustion limit. The orange line
represents the maximum flow rate of methanol; it is a hard constraint obtained
when the valve is fully open. Green and blue lines represent soft constraints: if
the process violates these two constraints, the operation profit will decrease. The
green boundary is the minimum opening for the methanol feed valve. The blue
boundary is the maximum acceptable methanol to air mole ratio which is 41%. If
the ratio goes over 41%, then more un-reacted methanol from reactor will go into
the downstream equipment, which increases absorber and distillation column
duties. The black dot at feasible region indicates sufficient flow rates at the
optimal ratio, which is 39:61for methanol to air flow rates respectively.
Regarding to the importance of the methanol and air mole ratio for the
whole operation, a ratio controller is recommended to regulate both flow rates.
Controlled flows of methanol are mixed in proper proportions with air through the
ratio controller arrangement before the reactants stream enters the reactor tubes.
Ratio control is a special type of feed forward control where two disturbances
0
50
100
150
200
250
40 50 60 70 80 90 100 110 120
Air F
low
rate
(km
ol/
h)
Methanol Flowrate (kmol/h)
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(loads) are measured and held in a constant ratio to each other. It is mostly used
to control the ratio of flow rates of two streams. Both flow rates are measured but
only one can be controlled. In this process, methanol stream is the one to be
controlled. When the ratio has been measured, it is compared to the desired ratio
(set point) and the deviation (error) between the measured and desired ratios
constitutes the actuating signal for the ratio controller. Therefore, based on the
operating window’s constraints to set ratio controller, it can easily adjust the ratio
to get the maximum yield.
4.2. FLEXIBILITY
The operation of the formaldehyde plant relies on the digital controllers at
control room; thus, operators must carefully observe and maintain all dials in the
operating room at the corresponding set points within the operating window. For
example, when the production rate must be increased, the operator can adjust
the air flow rate and formaldehyde outlet flow rate settings to be higher, and then
the computer will make adjustments to the methanol flow rate increase based on
the set point on the ratio controller as mentioned at the operating window.
Meanwhile, the BFW flow rate would automatically increase to cool down the
reactor, since more heat will be released from the reaction. The formaldehyde
plant was mostly automated apart from two actions, which are the two manually
controlled actions involved with emergency shut off and the valves used for by-
passing purposes. Both of these manual actions are with regard to safety issues.
Existing “steering wheels” were adequate in terms of safety and
efficiency. Alarms for low flow rate, low methanol to air ratio, high reactor
temperature to ensure the reactor unit works properly and safely, and actual
product outcome did not deviate far from the set point within the operating
window. Moreover, employment of the recycle streams is considered as
increased the flexibility. Methanol separated from the distillation column should
be recycled to the feed stream in order to mix with the new methanol to the
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reactor. This not only decreases the material cost for the plant, as methanol is
expensive, but also decreases environmental pollution.
Additional parallel equipment may also improve flexibility and reliability for
the formaldehyde plant, such as parallel valves, pumps, and so on. For example,
if the set point for production rate was set at maximum, both flow rates for
methanol and air would to increase respectively. However, one feed pump could
not afford the entire load; if there is a parallel pump present to share the load, it
would be enough methanol feed to mix with air to achieve set point methanol to
air ratio and set point production rate.
4.3. RELIABILITY
The formaldehyde plant achieved higher reliability based on strict regular
maintenance as opposed to equipment redundancy. Methanol and
formaldehyde are hazards to the environment and risky to health. Thus, failure of
plant was not acceptable primarily because of the effect on safety, not the affect
on production.
As mentioned at the flexibility section (4.2), additional parallel pumps and
valves could enhance the operating reliability. Other than sharing the heavy work
load for feed pump, employing a parallel pump can also increase the plant’s
availability. If one of the pumps does not work properly, the other pump can still
pump the feed to ensure the plant continues to operate. At the same time, a
technician can be sent to repair the malfunctioning pump. Another setup to
increase the reliability was employment of storage tanks before the recycle feed
pump to distillation column. This setup ensures that when there is not enough
recycled formaldehyde produced from the condenser, it would not affect the feed
to the pump, since the inventory of the storage tank could provide enough feed to
prevent cavitations. In general, the plant can operate 51 weeks in a year, and 24
hours per day [8]. The off-line week can be used for catalyst replacement and
simultaneous plant maintenance. All of these gives the plant had high plant
operability.
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The ability to repair, diagnose and replace parts or the process system is
not limited to the formaldehyde plant operators and technicians. For the most
part, trouble shooting was done by operations from the control room or at the
problem site. Operators are equipped to perform small replacements and
repairs. However, when the complexity or size of the maintenance is too large,
outside contractors were hired to perform the task. In order to limit the need for
large scale repairs, the operators follow a strict Preventative Maintenance (PM)
Schedule. The following are some of the Preventative Maintenance
procedures followed rigorously by operators [8]:
Daily Basis
Methanol, Air, and BFW cutoff check
Weekly Basis
Reactor alarms testing
Semi-Annually Basis
Regular equipment check
Safety check
Three Years Basis
Safety valves removed and sent out for certification
Though PMs may not always require a shut down, they are generally time
consuming and costly. However, most of may be scheduled at the same time
when catalyst replacement takes place. Nevertheless, the costs of PMs outweigh
that of large scale equipment damage and possible equipment failure.
4.4. EFFICIENCY
4.4.1. EQUIPMENT CAPACITY
Ideally, the reactor will function at around 71% efficiency. The reactor
operation is maintained by the air to methanol ratio. Therefore, the both flow
rates are controlled with a ratio control. The air input stream acts as the wild
stream, which is not under control. The methanol stream will be controlled to
meet the maximum feasibility. The optimal ratio of reactants is 39 weight percent
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methanols in air. This ratio must be adjusted before the feed enters the reactors
for the optimum productivity.
4.4.2. EQUIPMENT TECHNOLOGY
The equipment that is used in this plant is assumed to be all new. Most of
the equipment has a lifespan 8-10 years. Digital displays and digital controllers
are installed to allow the readings on the feed ratio. The digital control is there to
ensure safety and efficiency of the reactor. For the relieve valves, the
equipments will be check regularly and will be changed if it is ruptured. The
catalyst also will be replaced every 6 months to ensure maximum performance
[9].
4.4.3. EQUIPMENT UTILIZATION
In the production of formaldehyde, the usage of equipment depends on
the demands. However, since formaldehyde is a commodity with very high
demand every year, the production of the formaldehyde will continue normally. If
the price of methanol increased, the production rate will be adjusted. This is to
save the amount of electricity utilized and by producing more formaldehyde, the
extra cost will cover the lost from the increased in price of methanol.
In general, the production of formaldehyde will be mostly operated at
night. The electricity charge is much cheaper at night compare to in daylight.
Therefore, to increase energy efficiency, the plant will be operated mostly at night
to produce the same amount of formaldehyde.
4.4.4. PROCESS STRUCTURE
Due to the reaction is highly exothermic. The boiler feed water and the
reactor jacket is designed to produce steam from the reaction. The steam will
then be recycled to be use to heat up other solution. In this way, less power is
needed.
The heat exchanger inside the reactor is designed to cool down the
process. Instead of just dumping the catalyst into the reactor, the catalyst is
placed outside the heat exchanger. The silver wired gauze covering the outside
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of heat exchanger will increase the surface area and hence give a better chance
for the catalyst to react with the methanol.
4.4.5. OPERATING CONDITIONS
The air and methanol mixture enters the reactor at temperature of 172oC
and pressure of 255 kPa [6]. The temperature of the mixture is to be brought as
close as possible to the reaction temperature to save more energy. The higher
temperature will give a better condition for the catalyst to convert the methanol
into formaldehyde. In order to operate efficiently, the temperature of the reactor is
best maintained at 630-700oC [10].
4.4.6. CALCULATION OF EFFICIENCY
The efficiency of the reactor is measured using equation (3).
𝐸𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑐𝑦 = 𝐴𝑚𝑜𝑢𝑛𝑡 𝑜𝑓 𝐹𝑜𝑟𝑚𝑎𝑙𝑑𝑒 ℎ𝑦𝑑𝑒 𝐷𝑒𝑡𝑒𝑐𝑡𝑒𝑑
𝐴𝑚𝑜𝑢𝑛𝑡 𝑜𝑓 𝑀𝑒𝑡ℎ𝑎𝑛𝑜𝑙 𝐸𝑛𝑡𝑒𝑟𝑒𝑑 (3)
The amount of formaldehyde detected and the amount of methanol entered the
reactor are measured from the outlet and inlet stream of the reactor in kmol/h.
The amount of methanol entered the reactor is 94.12 kmol/h and the amount of
formaldehyde coming out of the reactor is 66.82 kmol/h total. This gives the total
efficiency of around 71%, which means that most of formaldehyde is converted in
the reactor. The calculation of the reactor efficiency is shown in Appendix A.
4.5. TRANSITION
4.5.1. START UP
Startup of the process takes between one and two hours, and is
completed when the reactor reaches a steady state temperature between 630
and 700oC [10]. Both the air and methanol feeds begin supplying the reactor
and combustion of the methanol is allowed to occur. However, mostly carbon
dioxide and water vapour are formed from the combustion, and the products are
vented from the reactor instead of proceeding through to the absorber. The
waste gas will contain traces of methanol and formaldehyde if no scrubbing is
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implemented to remove them. Once the reactor reaches its operating
temperature, the vent is closed and any products from the reaction are fed into
the absorber [11].
4.5.2. SHUT DOWN
Shutdown occurs by shutting off the methanol and air feeds to the
reactor. Any products formed at the time of shutoff are vented from the reactor
[8]. The vented gas will contain traces of methanol and formaldehyde unless it
is ignited at the vent outlet. Once flows have stopped and the reactor cooled
down, with traces of formaldehyde and methanol vented, it is possible to perform
maintenance on the process [8].
5. TROUBLESHOOTING
Due to the reaction is highly exothermic, the main trouble spot is on the
reactor. In the chemical reactor, if flow did not distributed, it would lead to “hot
spots” which can damage catalyst or vessel. In order to prevent those damages,
many temperature sensors are located at different locations in the bed provides
monitoring for poor distribution. Despite its high reliability, and low likelihood of
failure it can never been assumed the process is 100% trouble free. The fishbone
diagram and root cause table in Appendix B demonstrate some possible root
causes for high temperature in the reactor.
6. HEALTH AND SAFETY ASPECT
In 2008, Kolon chemical company in Korea exploded. From the explosion,
two workers died on site, and 14 people got severe injured. The causes of the
explosion were the out of control on temperature control in the reactor and
corrosion of the outlet pipe. In order to prevent this tragic accident, all employees
need to strictly train with MSDS and finish HAZOP analysis before runs the
process. HAZOP identification for the formalin plants is placed in Appendix C.
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6.1. MATERIAL SAFETY
According to MSDS in Appendix D both methanol and formaldehyde are
highly toxic and inflammable. Direct exposure of the formaldehyde and methanol
to the skin or eyes can cause severe irritation and burns [4], [12]. Any incidents
of exposure to skin must be immediately washed with copious amount of water.
Not only from the direct contact, but it also can cause severe organ damages by
inhalation or ingestion [4], [12]. Therefore, the safety regulation strictly followed in
order to prevent the exposure to chemicals and danger of fire. Furthermore
details on handling, storage, first aid, fire measure, toxicology and so on are
explained in MSDS.
6.2. PROCESS SAFETY
As mentioned before, the process safety is regulated automatically by
placing multiple sensors and controllers in cascade and feed forward system.
Automatic alarm system catches any errors when process variables have
exceeded set point and it also indicates sensor failures. Table 1 shown below
lists the alarm messages that annunciate to operator. Lights illuminate and
buzzer goes off when errors are detected.
When the alarm goes off and lights are on, it will annunciate the operator
about the exact problem. Then the operator can press a button to immediately
stop the buzzer and either begins to fix the problem or restart.
Table 1 List of alarm sign under possible system failure
Parameters Alarm
Air flow Out of 6~ 36% of air and meOH ratio range
High/low air feed flow
Methanol flow Out of 6~ 36% of air and meOH ratio range
High/ low methanol feed flow
Exceed 720C High temperature reactor
Rupture disc burst of condenser Reactor failed
Level of distillation tray low Level of distillation tray condition
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When part of the plant shut down to fix the problem, the equipment can be
damaged from the unexpected shut down. In order to prevent the damage,
multiple sensors and pumps installed in parallel, so it can function alternately to
continue the process. Therefore, it will not affect the main process.
Pressure relief valves builds on the reactor since the pressure of the steam
in the reactor would become too high to respond to controller also it can cause
high temperature. The spring release valves will allow the excess steam to
escape through pipes which lead to the roof of the building. And rupture disc will
build up next to valve as a back-up for larger relief.
Since the process dealing with highly toxic and flammable chemicals, when
it leaks or spilled, it should strictly follow containment system. For the spillage,
the area should evacuate and ventilate, and all possible source of ignition should
be eliminated. The spilled material should not empty into drain since it may
create fire or explosion.
A large red button for reactor is set up to enable a quick and immediate shut
down of the system and it should perform when the previous five safety
measures are not able to handle. Then, reactor will have to be restarted as
following the start up procedures. In this kind of a dangerous emergency,
evacuation of the building is necessary and the emergency unit will be respond.
7. ECONOMICS
7.1. RELEVANT ISSUES
7.1.1. METHANOL PRICE
Methanol is the primary feed in this plant. Methanol is directly converted
into formaldehyde and therefore it serves as essential part of the production. By
examining the methanol price in the past few years, it was observed that it
fluctuated in very high magnitude month by month. For example in January 2008,
the price went up to $832/ton whereas a year later in 2009, the price was marked
at $233/ton. Figure 4 summarizes the methanol price in past five years.
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Figure 4 Historic methanol price from 2006 to 2010 [13]
7.1.2. ONTARIO’S NEW SMART METER POLICY
Ontario’s Ministry of Energy launched new Smart Meter policy. During the
off-peak period, the price is 5.1 ¢/kWh and during the on-peak, it increases to 9.9
¢/kWh [14]. This rate would affect the utility cost significantly for the plants in
Ontario. It is important to well-understand the new rate policy in order to take
advantage of it.
Figure 5 Ontario's Smart Electricity Cost
7.1.3. HOUSING MARKET CRISIS IN 2007
The Subprime Mortgage Crisis in 2007 hit the entire global economy. As
it was directly related to the incident, the housing market in North America
suffered and resulted many bankruptcies [15]. As it was mentioned earlier,
$442
0
200
400
600
800
1000P
rice
(U
SD
/ton)
Off-peak Mid-peak On-peak
0.051
$/kWh
0.081
$/kWh
0.099
$/kWh
McMaster University Chemical Engineering 4N04 Final Report
formaldehyde manufacturing business heavily relies on the production of the
additive in wood products. Therefore the housing and construction market affect
the formaldehyde market. Because the housing market severely declined since
2007, the formaldehyde manufacturing business suffered as well. Figure 6 shows
the Standard & Poor’s Case-Shiller Index which is one of the housing price
indices. As it is shown in the figure, the housing market started decline during
2007.
Figure 6 Standard & Poor's Case-Shiffer home price index [15]
7.2. CAPITAL COST ESTIMATION
The capital cost of the plant was calculated using the cost estimation
calculations in Cost Estimation for the Process Industries by Dr. D. Woods [16].
There were seven heat exchangers (including one from the reactor), one reactor,
one compressor, two pumps and two separation equipments were considered. It
was concluded that the $5M ± 40% of capital cost required. The conclusion is
based on the bare module method of cost estimation. The Marshall & Swift
inflation factor between 1970 and 2009 was used to determine the present
purchase and installation costs for all components.
There were some unit-specific assumptions made during the calculations.
For example, the distillation column (T-02) was assumed to be a single pass type
100
150
200
Cas
e-S
hil
ler
Index
McMaster University Chemical Engineering 4N04 Final Report
since it would give a sufficient separation of methanol and formalin. The
efficiency of the equipments were also considered in the calculations.
The major expenditures came from purchasing and installing the reactor
($410,000) and the two separation equipments ($1.5M and $1.7M). The
spreadsheet Table E1 found in Appendix E shows more specific calculations and
the costs for each equipment.
7.3. OPERATING COST ESTIMATION
Many aspects of plant operations were considered in this section to
estimate the annual operating cost of the plant. Current price of methanol, water,
hydro and man-power costs were considered. Table E2 in appendix E shows
more details of the calculations for the operating cost.
As it is drawn in Figure 7, the major expenditure comes from purchasing
the feed methanol. Then the utility cost follows. By manufacturing about 35,000
ton of 37% formalin every year will yield $6.3M annual operation profit.
However, this plant has an expected age of 10 years. The Net Present
Value (NPV) calculation was necessary to find out the value of this project until it
reaches the shut-down or major maintenance. 35% of tax was used as it is
widely used as corporate rate. Considering the last 10 years of inflations, 3% of
inflation rate was assumed. The equipments purchased and installed in the
beginning of the project were depreciable. After 10 years of the project, the NPV
was found to be about $27.5M, which is quite profitable. The NPV calculation
table is found in Table E3 from appendix E.
It is important to notice that this calculation is based on very bold
assumption; the price of formaldehyde and the price of methanol do not change
during the operation. This, definitely, is not true. As it was mentioned above, the
prices fluctuate in a very rigorous manner. In order to perform a better estimation,
an in depth market analysis is necessary.
McMaster University Chemical Engineering 4N04 Final Report
Figure 7 Operating cost distribution
7.3.1. USING ONTARIO’S SMART RATE
The new policy on the electricity price would help to cut down the utility
cost. The plant is quite flexible in terms of production rate. It can increase and
decrease the formaldehyde production up to 20%. By increasing the production
rate during off-peak time and by decreasing during the on-peak time, it is still
possible to meet the annual production rate of 35,000 ton per year. An
investigation was done on how much the operating cost would be cut if this new
production rate was implemented. It was found that about $1M of utility cost
could be saved. The Table 2 shows the comparisons of the original and the new
method.
Table 2 Hydro cost calculated via original rate, summer and winter Smart rate
Energy uses (kW)
Original Rate
Smart Rate (Summer)
Smart Rate
(Winter)
15224.30556 $9,869,004 $8,922,113 $8,922,113
8. PROCESS RECOMMENDATIONS
The health risks of formaldehyde and methanol exposures are well
known. Chronic exposure to formaldehyde results in drying and cracking of the
skin, formation of lesions along the respiratory tract, and an increased risk of
contracting lung and nasal cancers. Exposure to methanol results in depression
Methanol
50%Energy
40%
Man-Power
4%
Others
6%
McMaster University Chemical Engineering 4N04 Final Report
of the central nervous system, abdominal pain, and liver damage, as methanol is
converted into formaldehyde in the liver. It is possible to implement measures to
avoid leaks, exposures and reduce overall emission levels at the plant level.
For instance, the methanol vaporizer unit experiences a doubling in
pressure between the inlet and outlet. An uncontrolled increase of pressure in the
vaporizer may result in a leakage of methanol should the equipment begin to fail.
The implementation of a rupture disk within the methanol vaporizer unit will
effectively prevent methanol leakage while relieving any built-up pressure in the
vaporizer.
To reduce the likelihood of formaldehyde leaks, hermetically-sealed
canned motor pumps should be used. A canned pump contains the motor and
pump within an enclosure that does not contain any seals that can fail.
Implementing such a pump will greatly reduce the likelihood of formaldehyde
leaks in the plant.
9. CONCLUSIONS
In conclusion, the formaldehyde production is a reliable process since the
chemical plant has high availability and flexibility with dependable safety
structures and troubleshooting systems. With a reliable process, the efficiency of
the conversion reactor from methanol to formaldehyde is 71%, which is relatively
efficient operation compared to other reactors using different catalysts or with
different setup.
With highly automated controls, the whole process would be operated at
the desired set points in the operating window. However, if the process violates
the constraints limited by the operating window, alarms would go off to notify the
system and the operators. Then, corresponding troubleshooting or safety
process would be taken.
Finally, installation of hermetically-sealed canned motor pumps is
recommended to prevent formaldehyde leaks in the plant. Besides preventing
formaldehyde leaking, a rupture disk should be installed in the methanol
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vaporizer unit to prevent any methanol leak as well. With all the additional
setups, the formaldehyde plant would achieve a safer and more efficient
manufacturing environment.
McMaster University Chemical Engineering 4N04 Final Report
REFERENCES
[1] Formaldehyde: Brief history and its contribution to society and the U.S. and
Canadian economies. Arlington: The Formaldehyde Council, Inc. Feb 2005
[2] Betsy Natz, FORMALDEHYDE: FACTS AND BACKGROUND INFORMATION.
Arlington: The Formaldehyde Council, Inc. 2007
[3] Bizzari, Sebastian N. "Formaldehyde." Chemical Industries Newletter [Menlo Park,
CA] Mar. 2007
[4] Formaldehyde, Material Safety Data Sheet version 1.10, Sigma Aldrich Inc.,
Missouri, USA, February 2007
[5] Smith, R. Chemical Process Design and Integration. Chichester, West Sussex,
England: Wiley, 2005
[6] Large-scale design project; Formalin plants, West Virginia University, 2006
[7] Dynea Ireland Limited. Dynea Ireland Limited Standard Operating Procedure.
Dublin: Dynea Ireland Limited. Apr. 2006
[8] Safety Report. Rep. Dynea, 2006. Emergency Response.
[9] Solomon, S.J, and T. Custer. Atmospheric Methanol Measurement Using Selective
Catalytic. Tech. Bremen: Atmospheric Chemistry and Physics, 2005.
[10] Cybulski, Andrzej, and Jacob A. Moulijn. Structured Catalysts and Reactors. Boca
Raton: Taylor & Francis, 2006
[11] Safriet, Dallas. Locating and Estimating Air Emissions from Sources of
Formaldehyde. EPA, 1991.
[12] Methanol, Material Safety Data Sheet version 1.10, Sigma Aldrich Inc., Missouri,
USA, February 2007
[13] Methanex Monthly Average Regional Posted Contract Price History.
[14] "How Will TOU Pricing Work?" Ontario. 2010. Web. 25 Nov. 2010.
<http://www.ontario.ca/YOURMINISTRY/en/index.php>
[15] The First Quarter of 2010 Indicates Some Weakening in Home Prices According to
the S&P/Case-Shiller Home Price Indices, S&P INDICES, May 2010
McMaster University Chemical Engineering 4N04 Final Report
[16] Woods, Donald R., Cost Estimation in the Process Industries, McMaster University,
1993
McMaster University Chemical Engineering 4N04 Final Report
APPENDIX
APPENDIX A- SAMPLE EFFICIENCY CALCULATIONS
Methanol Entered: 94.12 kmol/h
Formaldehyde Detected: 66.82 kmol/h
danolEntereAmountMeth
DetectedrmaldehydeAmountofFoEfficiency
12.94
82.66Efficiency
Therefore, efficiency = 71%
McMaster University Chemical Engineering 4N04 Final Report
APPENDIX B- TROUBLESHOOTING FISHBONE DIAGRAM AND TABLE
Table B 1 High temperature of reactor causes and solutions
Root Cause Symptoms Solutions
Sensor Failure Unfeasible data output
Zero output read
Regular maintenance check
Preventative maintenance
Scaling/Fouling Low Flow rate
Regular maintenance check
By-pass piping
Low contaminant of water and air
Insufficient
BFW
Poor cooling
BFW level low Check source of leaks
Relief valve
open failure
Pressure valve damaged
Low pressure reading Regular maintenance check
McMaster University Chemical Engineering 4N04 Final Report
APPENDIX C - HAZOP
Unit: R-801 Formaldehyde Reactor
Node: BFW inlet (after the feed valve, before entering the reactor)
Parameter: Flow
Guide Word Deviation Cause Consequence Action
1. feed valve closed 1. temperature increase in
reactor
1. install back-up
control valves, or
manual bypass valve
2. level controller
fails and closes
valve
2. damage to the reactor,
possible heat exchanger
tubes failure
2. install back-up
controller
3. Air pressure to
drive valve fails.
Cosing valve
3. install control valve
that fails open
4. pipe blockage 4. a) test flow before
startup b) place filter
in pipe
5. boiler feedwater
service failure
5. install back-up BFW
source
6. install high
temperature alarm to
alert operator
7. Install high
temperature
emergency shutdown
8. install BFW flow
meter and low flow
alarm
more more BFW flow 1. feed valve fails
and open
1. reactor cools, however,
water builds-up
1. instruct operators
on procedure
2. controller fails and
opens valve
less less BFW flow 1. partially plugged
feed line
1. covered under "NO" 1. cover under "NO"
2. partial water
source failure
3. control valve fails
to repond
reverse reverse BFW
flow
1. failure of water
source resulting in
back ward flow
1. improper cooling,
possible runaway
1. install check valve
in BFW line
2. back flow due to
reactor pressure
2. install high pressure
alarm to alert operator
other than another material
besides BFW
1. water source
contaminated
1. possible loss of cooling
with possible runaway
1. isolation of BFW
source
2. possible damage the
reactor
2. install high
temperature alarm
no no BFW flow
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Node: methanol inlet flow (Stream-6, after the preheater, before mix with air)
Parameter: Flow
Guide Word Deviation Cause Consequence Action
no no methanol inlet
flow
1. pump failure 1. deficient quality product 1. install a low level
alarm on the adiabatic
reactor section
2. feed valves closed 2. backward flow, damage
the pump
2. install kick-back on
pumps
3. pipe blockage 3. high pollution 3. install a controllor
for valve's opened
4. methonal service
failure
4. regular inspection
and patrolling of
methanol transfer
lines and seals
5. install back-up
methanol resource
more more methanol
inlet flow
1. feed valve fails
and open
1. a) lower reaction rate b)
increase unused methanol
1. install flowmeter
after the pump
2. heat exchanger
tube leaks
2.deficient quality product 2. install controller for
valve's open
adjustment which
depends on the
flowrate of air
3. acidic product corroding
the adiabatic reactor shells
3. install ratio sensor
after the air stream
and methanol stream
mix
4. install ratio sensor
at the reactor product
stream
less less methanol
inlet flow
1. valve fails to open 1. cover under "NO" 1. cover under "NO"
2. partially plugged
feed line
other than another material
besides
methanol
1. methanol cource
contaminated
1. corrosion at the
adiabatic reactor
1. isolation of
methanol source
2. deficient quality product
McMaster University Chemical Engineering 4N04 Final Report
Node: reactor tank
Parameter: Pressure
Guide Word Deviation Cause Consequence Action
high high pressure 1. relief valve fails 1. pressure builds-up,
reactor tank explosion,
possible pipe falure
1. a) install pressure
sensor b) install back-
up relief valve
2. steam outlet line
blocked
2. vapour containts
statureated inside the
tank, temperuature
increase
2. test the steam flow
before startup
3. cooling water
temperature is high
3. vapour builds-up,
inefficient to remove heat
3. install temperature
meter
4. reaction rate over
the range
4. install high pressure
alarm to alert operator
5. reactants and
products outlet
blocked
5. install a pump at the
outlet
6. install flowmeter at
the reatant inlet
low low pressure 1. reactor tank
opens to
atmosphere
1. steam runaway, waste
energy, possible pollution
1. a) install ratio
sensor b) instruce
operators on
procedure
2. no cooling BFW
flow
2. reactor over heat,
temperature increase,
possible tank and pipe
failure
2. install high
temperaure alarm to
alert operator
3. reactant pipe line
blocked
3. no reaction take plance,
waste cooling feed and
energy
3. a) install flowmeter
at reactant pipe line
b) test the flow before
startup
4. relief valve fails to
close
McMaster University Chemical Engineering 4N04 Final Report
APPENDIX D - MSDS OF FORMALDEHYDE AND METHANOL
Table D 1 MSDS of Formaldehyde
Name CAS # % TLV
1. Formaldehyde 50-00-0 30-40 Exposure limits: 0.3 ppm (0.37 mg/m3)
2. Methanol 67-56-1 15-May Exposure limits: 200 ppm (262 mg/m3)
3. Water 7732-18-5 Balance N/A
Physical state
pH
Odour threshold
Percent volatile
Freezing point
Boiling point
Specific gravity
Vapour pressure
Vapour density
Evaporation rate
Solubility
Flash point
Flammability
Fire extinguishing
procedures
Stability
Incompatibility
Routes of entry
Effects of acute
exposure
Effects of chronic
exposure
1.08 to 1.0975 (water = 1)
~40 mm of Hg (@39 ˚C)
0.62 to 1.04 (Air = 1)
Section 1: Hazardous Ingredients
Section 2: Physical Data
Section 3: Fire and Explosion Data
Section 5: Toxicology Properties
May react violently with: acids, alkalis, anhydrides, isocyanates, urea, phenol,
oxidizing agents, oxides, organic oxides, reducing agents, ammonia, aniline,
magnesium carbonate, performic acid, alkali metals, amines, hydrogen
peroxide, nitromethane, nitrogen dioxide, perchloric acid, perchloric acid-aniline
mixtures, bases, monomers, water reactive materials, magnesium carbonate
hydroxide.
Inhalation, ingestion, absorption through skin and eyes.
Death if inhaled or absorbed; severe eye irritation and burns; allergic dermatitis,
skin burns; bronchitis, pulmonary oedema; headache, dizziness, nausea,
vomiting; abdominal pain; blindness.
Nasal cancer, respiratory tract irritation; reproductive disorders, asthma,
dermatitis; multiple organ damage.
2.1 (n-Butyl acetate = 1) (Methanol).
Section 4: Reactivity Data
Miscible in water
50 - 78 degrees Celsius
Lower: 7%; Upper: 73%
Use DRY chemical, carbon dioxide, alcohol-resistant foam or water spray. Cool
containing vessels with flooding quantities of water until well after fire is out.
Stable. Conditions to avoid: heat, sparks and flame, temperatures below 20°C.
Clear, colourless liquid with strong formaldehyde odour.
2.8 - 4.0 (25 degree Celsius) (37% solution)
0.8 - 1 ppm
100% (V/V)
Insoluble polymer gradually forms.
90 - 100
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Protective clothing
and PPE
Handling procedures
Spill Containment
Eye contact
Sking contact
Inhalation
Ingestion
Immediate first aid is needed to prevent eye damage. IMMEDIATELY flush eyes
with copious quantities of water for at least 20 minutes holding lids apart to
ensure flushing of the entire surface. Seek immediate medical attention.
DO NOT use an eye ointment.
Immediate first aid is needed to prevent skin damage. Immediately flush skin
with plenty of water for at least 20 minutes while removing contaminated
clothing and shoes. Seek immediate medical attention. Wash contaminated
clothing before reusing.
Remove patient to fresh air. Administer approved oxygen supply if breathing is
difficult. Administer artificial respiration or CPR if breathing has ceased. Seek
immediate medical attention.
If conscious, wash out mouth with water. DO NOT induce vomiting. Seek
immediate medical attention.
Section 6: Preventative Measures
Wear self-contained breathing apparatus, rubber boots and heavy rubber
gloves, and an acid suit.
Store in a cool place away from heated areas, sparks, and flame. Store in a well
ventilated area. Store away from incompatible materials. Do not add any other
material to the container. Do not wash down the drain. Do not breathe
gas/fumes/vapor/spray. In case of insufficient ventilation, wear suitable
respiratory equipment. Keep container tightly closed. Manipulate under an
adequate fume hood. Take precautionary measures against electrostatic
discharges. Ground the container while dispensing. Ground all equipment
containing material. Use only explosion proof equipment. Use non-sparking
tools. Watch for accumulation in low confined areas. Do not use pressure to
dispense. Storage temperature depends on methanol content and should be
controlled to avoid precipitation or vaporization. Handle and open container with
care. Take off immediately all contaminated clothing. This product must be
manipulated by qualified personnel. Do not get in eyes, on
skin, or on clothing. Wash well after use. In accordance with good storage and
handling practices. Do not allow smoking and food consumption while handling.
Section 7: First Aid Measures
Evacuate and ventilate the area. Stay upwind: Keep out of low areas. Eliminate
all sources of ignition. Dyke the area with sand or a natural barrier. Absorb on
sand or vermiculite and place in a closed container for disposal. Use nonsparking
tools. Transport outdoors. Wash spill site after material pick up is
complete. DO NOT empty into drains. DO NOT touch damaged container or
spilled material. Runoff to sewer may create fire or explosion hazard.
McMaster University Chemical Engineering 4N04 Final Report
Table D 2 MSDS of Methanol
Name % (w/w) Exposure Limits LD60 LC60
Methanol
(CAS 67-56-1)
99-100 ACGIH TLV-TWA: 200 ppm, skin
STEL: 250 ppm, skin notation
OSHA PEL: 200 ppm
TLV Basis, critical effects:
neuropathy, vision, central
nervous system
5628 mg/kg
(oral/rat)
20mL/kg
(dermal/
rabbit)
64000 ppm
(inhalation/
rat)
Physical state
pH
Odour threshold
Freezing point
Boiling point
Vapour pressure
Vapour density
Solubility
Flash point
Autoignition temperature:
Lower Explosive Limit:
Upper Explosion Limit:
Sensitivity to impact:
Sensitivity to Static Discharge:
Hazardous Combustion Products:
Extinguishing Media:
Toxic gases and vapours; oxides of carbon and formaldehyde
Small fires: Dry chemical, CO2, water spray
Large fires: Water spray, AFFF(R) (Aqueous Film Forming Foam
(alcohol resistant) type with either a 3% or 6% foam proportioning
system.
Fire Fighting Instructions: Methanol burns with a clean clear flame that is almost invisible in daylight.
Stay upwind! Isolate and restrict area access. Concentrations of greater that 25% methanol in water can
be ignited. Use fine water spray or fog to control fire spread and cool adjacent structures or containers.
Contain fire control water for later disposal. Fire fighters must wear full face, positive pressure, self-
contained breathing apparatus or airline and appropriate protective clothing. Protective fire fighting
structural clothing is not effective protection from methanol. Do not walk through spilled product.
: - 97.8˚C
64.7 ˚C @ 101.3 kPa
12.8 kPa @ 20 ˚C
1.105 @ 15 ˚C
11 ˚C (TCC)
Section 3: Fire and Explosion Data
Miscible in water
6% (NFPA, 1978)
36% (NFPA, 1978), 36.5% (Ullmann, 1975)
Low
Low
385 ˚C (NFPA 1978), 470 ˚C (Kirk-Othmer 1981; Ullmann 1975)
detection: 4.2 - 5960 ppm
(geometric mean) 160 ppm
recognition: 53 - 8940 ppm
(geometric mean) 690 ppm
Not applicable
Liquid, clear, colourless
Section 2: Physical Data
Section 1: Hazardous Ingredients
McMaster University Chemical Engineering 4N04 Final Report
Routes of entry
Effects of acute
exposure
Effects of chronic
exposure
Protective clothing
and PPE
Handling procedures
Spill Containment
Inhalation, ingestion, absorption through skin and eyes.
Section 5: Preventative Measures
Engineering Controls: In confined areas, local and general ventilation
should be provided to maintain airborne concentrations beloew
permissable exposure limits. Ventilation systems must be designed
according to approved engineering standards.
Respiratory Protection: NIOSH approved supplied air respirator when
airborne concentrations exceed exposure limits.
Skin protection: Butyl and nitrile rubbers are recommended for
gloves. Check with manufacturer. Wear chemical resistant pants and
jackets, preferably of butyl or nitrile rubber. Check with manufacturer.
Eye and Face Protection: Face shield and chemical splash goggles
when transferring is taking place.
Footwear: Chemical resistant, and as specified by the workplace.
Other: Eyewash and showers should be located near work areas.
NOTE: PPE must not be considered a long-term solution to exposure
control. PPE usage must be accompanied by employer programs to
properly select, maintain, clean, fit and use. Consult a competent
industrial hygiene resource to determine hazard potential and/or the
PPE manufacturers to ensure adequate protection.
Handling Procedures: No smoking or open flame in storage, use or
handling areas. Use explosion proof electrical equipment. Ensure
proper electrical grouding procedures are in place.
Storage: Store in totally enclosed equipment, designed to avoid
ignition and human contact. Tanks must be grounded, vented, and
should have vapour emission controls. Anhydrous methanol is non-
corrosive to most metals at ambient temperatures except for lead,
nickel, monel, cast iron and high silicon iron.
Soak up spill with non-combustible absorbent material. Recover
methanol and dilute with water to reduce fire hazard. Prevent spilled
methanol from entering sewers, confined spaces, drains, or
waterways. Restict access to unprotected personnel. Full. Put material
in suitable, covered, labeled containers. Flush area with water.
irriate mucous membranes, headaches, sleepiness, nausea, confusion,
digestive and visual disturbances, irritation of eyes or skin
brain disorder, blindness, emphysema, bronchitis
dermatitis; multiple organ damage.
Section 4: Toxicology Properties
McMaster University Chemical Engineering 4N04 Final Report
Eye contact
Sking contact
Inhalation
Ingestion
Remove contact lenses if worn. In case of contact, immediately flush
eyes with plenty of clean running water for at least 15 minutes, lifting
the upper and lower eyelids occasionally. Obtain medical attention.
In case of contact, remove contaminated clothing. In a shower, wash
affected areas with soap and water for at least 15 minutes. Seek
medical attention if irritation occurs or persists. Wash clothing before
reuse.
Remove to fresh air, restore or assist breathing if necessary. Obtain
medical attention.
Ingestion: Swallowing methanol is potentially life threatening. Onset
of symptoms may be delayed for 18 to 24 hours after digestion. If
conscious and medical aid is not immediately
Section 6: First Aid Measures
McMaster University Chemical Engineering 4N04 Final Report
APPENDIX E –CAPITAL & OPERATING COST CALCULATION
Table E 1 Capital Cost Table
Heat Exchangers
Area in m2 FOB Type Material Co 2009
Cost for
installationFp Fm
Additional
Factor
Additional
FOB Costs
Additional
Pipe CostsTotal BM
E-01 400 $21,407Floating
Headcarbon steel $104,445 $223,513 0.9 1 1 -$2,783 -$896 $324,280
E-02 5 $954Floating
Headcarbon steel $4,653 $9,957 0.9 1 1 -$124 -$40 $14,445
E-03 30 $3,403Floating
Headcarbon steel $16,603 $35,530 0.9 1 1 -$442 -$142 $51,548
E-04 40 $4,174Kettle
Reboilercarbon steel $20,365 $43,582 0.9 1 1.35 $728 $235 $64,910
E-05 300 $17,452Floating
Headcarbon steel $85,150 $182,220 0.9 1 1 -$2,269 -$731 $264,371
E-06 50 $4,891Floating
Headcarbon steel $23,861 $51,063 0.9 1 1 -$636 -$205 $74,084
Compressors
Capacity
(kW)FOB Type Material Co 2009
Cost for
installationFp Fm
Additional
Factor
Additional
FOB Costs
Additional
Pipe CostsTotal BM
C-01 200 $39,937 Centrifugal carbon steel $194,856 $420,888 $615,744
Pumps
Capacity
(kW)FOB Type Material Co 2009
Cost for
installationFp Fm
Addition
FOB Costs
Additional
Pipe CostsTotal BM
P-01 0.5 $344 Centrifugal Cast Iron $1,679 $3,862 1 1 $0 $0 $5,542
P-02 0.5 $344 Centrifugal Cast Iron $1,679 $3,862 1 1 $0 $0 $5,542
P-03 0.5 $344 Centrifugal Cast Iron $1,679 $3,862 1 1 $0 $0 $5,542
Separation Towers
Size FOB Type Material Co 2009Cost for
installationFp Fm
Additional
Factor
Addition
FOB Costs
Additional
Pipe CostsTotal BM
T-01 25.22 $72,510 Absorber Carbon Steel $353,781 $1,117,948 1 1 $0 $0 $1,471,729
T-02 2.5 $82,733 Single Pass Carbon Steel $403,659 $1,275,564 1 1 1.2 $16,547 $5,328 $1,701,098
Reactor
Size FOB Type Material Co 2009Cost for
installationFp Fm
Additional
Factor
Addition
FOB Costs
Additional
Pipe CostsTotal BM
R-01 30 $12,200 Carbon Steel $59,524 $188,097 1.3 1 1.3 $8,418 $2,711 $258,750
Heat Exchanger (within reactor)
Area in m2 FOB Type Material Co 2009
Cost for
installationFp Fm
Additional
Factor
Additional
FOB Costs
Additional
Pipe CostsTotal BM
150 $10,669Floating
Headcarbon steel $52,054 $111,395 0.9 1 1 -$1,387 -$447 $161,615
Capital Cost
Total
$5,019,199
± 40%
McMaster University Chemical Engineering 4N04 Final Report
Table E 2 Operating Cost Table
Operating Cost Feed
Per year Price/unit Total
Water 21900 1.4726 $/m3 $32,250
Methanol 27375 442 $/metric tonne $12,099,750
Energy
Equipment
Energy uses
(MJ/h)
Energy uses
(kW) Hourly Cost Annual Cost
E-01 4000 1111.11 $82 $720,267
E-02 100 27.78 $2 $18,007
E-04 40000 11111.11 $822 $7,202,667
R-01 10000 2777.78 $206 $1,800,667
C-01 700 194.44 $14 $126,047
P-01 2.5 0.69 $0 $450
P-02 2.5 0.69 $0 $450
P-03 2.5 0.69 $0 $450
Total 54807.5 15224.31 $1,127 $9,869,004
Man Power
Classification
Number of
Persons $/year Subtotal
Plant Manager 1 $100,000
$100,000
Engineer 3 $60,000
$180,000
Production
Operator 9 $40,000
$360,000
General Workers 12 $35,000
$420,000
Total 25
$1,060,000
Total Operating
Cost $23,028,754
Revenue Product
Per year Price/unit Total
Formalin 35040 837.76 $/metric tonne $29,355,110
McMaster University Chemical Engineering 4N04 Final Report
Table E 3 Net present value calculations
0 1 2 3 4 5
Capital Cost -$5,019,199
Water -$32,250 -$32,250 -$32,250 -$32,250 -$32,250
Methanol -$12,099,750 -$12,099,750 -$12,099,750 -$12,099,750 -$12,099,750
Energy -$9,869,004 -$9,869,004 -$9,869,004 -$9,869,004 -$9,869,004
Man-Power Cost -$1,060,000 -$1,060,000 -$1,060,000 -$1,060,000 -$1,060,000
Revenue $29,355,110 $29,355,110 $29,355,110 $29,355,110 $29,355,110
NCFBT -$5,019,199 $6,294,106 $6,294,106 $6,294,106 $6,294,106 $6,294,106
Account Balance -$5,019,199 $1,274,907 $7,569,013 $13,863,119 $20,157,225 $26,451,331
Depreciation $1,505,760 $1,054,032 $737,822 $516,476 $361,533
Book Value $5,019,199 $3,513,439 $2,459,408 $1,721,585 $1,205,110 $843,577
Gain Loss
Taxable Income $0 $7,799,866 $7,348,138 $7,031,928 $6,810,582 $6,655,639
Tax Payment $0 $2,729,953 $2,571,848 $2,461,175 $2,383,704 $2,329,474
NCFAT -$5,019,199 $3,564,153 $3,722,258 $3,832,931 $3,910,402 $3,964,632
Present Value -$5,019,199 $3,460,343 $3,508,585 $3,507,675 $3,474,342 $3,419,927
6 7 8 9 10
Capital Cost
Water -$32,250 -$32,250 -$32,250 -$32,250 -$32,250
Methanol -$12,099,750 -$12,099,750 -$12,099,750 -$12,099,750 -$12,099,750
Energy -$9,869,004 -$9,869,004 -$9,869,004 -$9,869,004 -$9,869,004
Man-Power Cost -$1,060,000 -$1,060,000 -$1,060,000 -$1,060,000 -$1,060,000
Revenue $29,355,110 $29,355,110 $29,355,110 $29,355,110 $29,355,110
NCFBT $6,294,106 $6,294,106 $6,294,106 $6,294,106 $6,294,106
Account Balance $32,745,437 $39,039,543 $45,333,649 $51,627,755 $57,921,861
Depreciation $253,073 $177,151 $124,006 $86,804 $60,763
Book Value $590,504 $413,353 $289,347 $202,543 $141,780
Gain Loss -$4,517,279
Taxable Income $6,547,179 $6,471,257 $6,418,112 $6,380,910 $6,354,869
Tax Payment $2,291,513 $2,264,940 $2,246,339 $2,233,319 $2,224,204
NCFAT $4,002,593 $3,615,813 $3,758,420 $3,858,245 $3,928,122
Present Value $3,352,109 $2,939,987 $2,966,931 $2,957,023 $2,922,892
NPV $27,490,615
Year
*35% Tax Rate and 3% Inflation Rate Used
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