Catalytic Conversion (via Soft Oxidation) of Methane to Ethylene

Group 5

AgendaBackground IntroductionProject Objectives and Production

TargetsConstraints and Tentative Flow

DiagramSafety and Environmental

ConcernsMarket Analysis

IntroductionWhy 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.

IntroductionCurrent 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 ObjectivesWith 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 STEPSI. Reaction Site

Soft oxidation of methane with sulfurII. 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 MixersAbsorber Distillation Column

TENTATIVE FLOW DIAGRAM

Environmental concernsThree 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 damageEthylene environmental hazard: C2H4 can cause damage to plants and materials as

a VOC

Health Concerns CS2

Hydrocarbons

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 neuro-physiological 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

OSHA: Occupational safety and Health AdministrationACGIH: American Conference of Industrial HygienistsPEL: Permissible Exposure Limit ; STEL: Short-term exposure limit TWA: Time-weighted average

CS2 Hydrocarbons H2S CH3SH

C2H4

Permissible Exposure Limits (PEL) by OSHA

STEL(1989): -12 ppm, 15 minsTWA (1989): -12 mg/m³, 8 hrs.

-Not available

STEL (1989)-21mg/m3 ,15 min- 15 ppm, 15 min

TWA (2012):-1 mg/m³, 8 hrs-0.5 ppm, 8 hrs

-Not available

Threshold Limit values (TLV) by ACGIH

TWA (2009): -1 ppm, 8 hrs

TWA(2010)-1000 ppm,8hrs

STEL (2010):-5ppm, 15 min TWA (2010)- 1 ppm 8hrs

TWA (2012):-0.98 mg/m³,- 8 hrs. -0.5 ppm8 hrs

TWA(2010):-200 ppm 8 hrs

Safety PrecautionsHIGH 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 PropyleneExpanding At A Rapid Pace

Ethylene is the largest of the basic chemical building blocksEthylene, propylene and methanol are expanding at a rapid pace…driven by shale in North AmericaBenzene and chlorine showing more modest growth

Ethylene, Methanol and PropyleneExpanding 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 ByDurable/Non-durable Goods

• Strong economic growthsupports basic chemicaldemand growth• Modest growth in 2012/13suggesting lowerconsumer spending• Emerging markets aredriving tomorrows demandgrowth• China dynamics arechanging, but remainscritical to most markets

Ethylene Investments

North America Ethylene CapacityForecast To Reach 45 Million Metric Tons

Thank you!

QUESTIONS????