Team5-Project2-Metha..

Report
Catalytic Conversion (via Soft
Oxidation) of Methane to Ethylene
Group 5
Agenda
 Background
Introduction
 Project Objectives and Production Targets
 Constraints and Tentative Flow Diagram
 Safety and Environmental Concerns
 Market Analysis
Introduction
Why we are interested in ethylene and its derivatives?
Ethylene is the world’s largest commodity chemical
and the chemical industry’s fundamental building block.
Ethylene and its derivatives applications
Introduction

Natural gas: is abundant hydrocarbon
feedstock.

Methane: is the principal component of
natural gas, has high hydrogen: carbon ratio.
Introduction
Current approaches for the direct, large-scale
chemical transformation of methane to useful
chemicals: aromatization, oxyclorination, and
oxidative coupling.
Disadvantages: modest selectivity and yield,
requirement for corrosive reagents, heat
management and temperature control.
 New approach???
Sulfur: a soft oxidant for conversion of
methane to ethylene
=> Using gaseous sulfur (S2) as a soft oxidant can hinder
the over-oxidation of methane when compared with using
O2 as oxidant.
Project Objectives

With feedstock as natural gas that has the
same composition in project 1, we study and
maximize ethylene production from methane
through oxidation conversion.

CHEMCAD would be used as design
simulator to assert the process and economic
feasibility of the project.
Production Targets
100 molar basis of feed gas:
 The highest possible recovery ethylene C2H4.
 Minimal H2S release to meet environmental
regulation.
 Minimize the formation of undesirable
byproducts during the conversion of CH4 to
C2H4.
 High ROI.
Constraints
 Modest
selectivities and yields

Heat management and temperature control

Requirement for corrosive reagents

Dependence on highly toxic halogenated
intermediates

Highly capital-intensive
GENERAL STEPS
I.
Reaction Site
 Soft oxidation of methane with sulfur
II.
Purification Site
 H2S absorption with DEA
 Regeneration of DEA
III.
Separation Site
 CS2 removal
 CH4 removal (Recycle back to feed)
 C2H6 removal
UNIT OPERATIONS
Kinetic Reactor
 Pumps
 Heat Exchangers
 Mixers
 Absorber
 Distillation Column

TENTATIVE FLOW DIAGRAM
Environmental concerns
Three main issues considered when dealing with the production of
ethylene :
 Global
warming
 Greenhouse gas effects contributed by CS2 and
CH4
 Extensive use of land
 Drilling pads
 Landscape damage
 Ethylene environmental hazard:
 C2H4 can cause damage to plants and materials as
a VOC
Health Concerns
CS2
Hydroca
rbons
H2S
CH3SH
C2H4
Potential
acute
health
effects
-Irritating
to eyes,
skin and
respiratory
system
- Harmful if
swallowed.
-May cause
burns or
frostbites
-Act as a
simple
asphyxiant
Moderately
irritating to
eyes and
skin
- May cause
burns or
frostbites
-very toxic
to
inhalation
-Irritating
to eyes
-May causes
severe
burns or
frostbites
-very toxic
by
inhalation
May causes severe
burns or frostbites
-acts as a simple
asphyxiant.
Potential
chronic
health
effects
Behavioral
and neurophysiologic
al changes.
-reduced
nerve
conduction
velocity.
Possible
damage to
heart and
central
nervous
system
Possible
damage to
lungs, upper
respiratory
tract, eyes,
central
nervous
system
Possible
damage to
blood, eyes,
kidneys,
lungs, livers,
and upper
respiratory
tract.
Possible damage
to lungs,heart,
Muscle tissue.
Exposure Limits Regulations
CS2
Hydrocarbons
H2S
Permissible
Exposure
Limits (PEL)
by OSHA
STEL(1989): -Not available
-12 ppm,
15 mins
TWA
(1989): -12
mg/m³, 8
hrs.
STEL (1989)
-21mg/m3 ,
15 min
- 15 ppm,
15 min
TWA (2012): -Not
-1 mg/m³,
available
8 hrs
-0.5 ppm,
8 hrs
Threshold
Limit values
(TLV) by
ACGIH
TWA
(2009):
-1 ppm,
8 hrs
STEL (2010):
-5ppm,
15 min
TWA (2010)
- 1 ppm
8hrs
TWA (2012): TWA(2010):
-0.98 mg/m³, -200 ppm
- 8 hrs.
8 hrs
-0.5 ppm
8 hrs
TWA(2010)
-1000
ppm,8hrs
CH3SH
OSHA: Occupational safety and Health Administration
ACGIH: American Conference of Industrial Hygienists
PEL: Permissible Exposure Limit ; STEL: Short-term exposure limit
TWA: Time-weighted average
C2H4
Safety Precautions
HIGH CONTROL SYSTEMS

Vibration alarms, toxic gas detectors, combustible gas or fire
detectors to potential emergency situations detections

Enclose operations and provide local exhaust ventilation at the site
of chemical release.

Provision of fire protection and emergency facilities by additional
facilities for emergency shutdown and isolation.

Secondary enclosures (building a vessel around the equipment) for
catching leaks for storage or handling of highly toxic materials
discharges, or others.

Use of respiratory and protective equipment
Ethylene, Methanol and Propylene
Expanding At A Rapid Pace
Ethylene is the largest
of the basic chemical
building blocks
 Ethylene, propylene
and methanol are
expanding at a rapid
pace…driven by shale
in North America
 Benzene and chlorine
showing more modest
growth

Ethylene, Methanol and Propylene
Expanding At A Rapid Pace
2020 Global Capacity:

Ethylene:200 Million Tons

Methanol:160 Million Tons

Propylene:140 Million Tons
Price trend of Ethylene
Demand for Basic Chemicals Driven By
Durable/Non-durable Goods
• Strong economic growth
supports basic chemical
demand growth
• Modest growth in 2012/13
suggesting lower
consumer spending
• Emerging markets are
driving tomorrows demand
growth
• China dynamics are
changing, but remains
critical to most markets
Ethylene Investments
North America Ethylene Capacity
Forecast To Reach 45 Million Metric Tons
Thank you!
QUESTIONS????

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