Introduction to Pre-reformer Flowsheet Options

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Introduction Pre- Reformer Flowsheet Options By: Gerard B. Hawkins Managing Director, CEO

description

Pre-reformer in the flowsheet * positioned upstream of the steam reformer * uses a specialized high activity catalyst based on Ni * reaction involves conversion of hydrocarbons to a mix of CH4, CO, CO2 and H2 Pre-reformers - sometimes included at the original design stage - also can be added to existing units to uprate the plant

Transcript of Introduction to Pre-reformer Flowsheet Options

Page 1: Introduction to Pre-reformer Flowsheet Options

Introduction Pre-Reformer Flowsheet

Options By:

Gerard B. Hawkins

Managing Director, CEO

Page 2: Introduction to Pre-reformer Flowsheet Options

Steam Reforming Section - Pre-reformer

Single adiabatic reactor • upstream of the steam reformer • uses high activity Ni based catalyst

Converts hydrocarbons to methane, CO, CO2 and H2 • Eliminates C2 and higher hydrocarbons

from feed • Makes life easy for the steam reformer

!!

Page 3: Introduction to Pre-reformer Flowsheet Options

Steam Reforming Section - Pre-reformer: Why ?

High efficiency/low energy plants Low steam export – benefit if steam not

required Smaller and high heat flux reformers

• Lower reformer capex (offset by pre-reformer capex)

Simplified and robust steam reformer operation

Means to deliver feedstock flexibility (not only means) between lighter and heavier feeds

Page 4: Introduction to Pre-reformer Flowsheet Options

Steam Reforming Section - Pre-reformer: Why Not ?

Additional equipment • Capex (offset by smaller reformer ?) • Opex (catalyst; maintenance; ….)

Complicated and delicate pre-reformer operation • Easily damaged expensive catalyst

Low steam export – problem if steam export valued/required

Economics suggest that pre-reformer is not the only solution if feedstock flexibility is required

Page 5: Introduction to Pre-reformer Flowsheet Options

Process Steam

Hydrocarbon Feed

HDS

Reformed Gas

Fuel

ZnO

Steam Generation and Superheating

Combustion Air

Pre-heat

Pre-reformer

Steam Reforming Section - Pre-reformer: Scheme without Re-heat

Page 6: Introduction to Pre-reformer Flowsheet Options

Process Steam

Hydrocarbon Feed

HDS

Reformed Gas

Fuel

ZnO

Steam Generation and Superheating

Combustion Air

Pre-heat

Pre-reformer

Steam Reforming Section - Pre-reformer: Scheme with Re-heat

Page 7: Introduction to Pre-reformer Flowsheet Options

Steam Reforming Section - Pre-reformer: Why or Why Not Re-heat ?

Endothermic steam reforming at inlet (both beds) Methanation causes exotherm with naphtha

525 500 475 450 400 350

Tem

pera

ture

(oC

)

Natural Gas

Inlet Exit

947 932 887 842 752 662

Temperature ( oF)

Naphtha

Inlet Exit

Page 8: Introduction to Pre-reformer Flowsheet Options

Summary

High level review of syngas flowsheets

Key differences and options highlighted

Increased awareness but many further layers of detail exist

Page 9: Introduction to Pre-reformer Flowsheet Options