H2A Case Study: Current Central Natural Gas Reforming without Sequestration

Project Summary

Full Title:	H2A Case Study: Current (2005) Central Hydrogen from Natural Gas without CO2 Capture and Sequestration
Project ID:	233
Principal Investigator:	Darlene Steward
Keywords:	Hydrogen production; steam methane reforming; natural gas

Purpose

Steam reforming of hydrocarbons continues to be the most efficient, economical, and widely used process for production of hydrogen and hydrogen/carbon monoxide mixtures. The purpose of this analysis is to assess the economic production of hydrogen from the steam reforming of natural gas.

Performer

Principal Investigator:	Darlene Steward
Organization:	National Renewable Energy Laboratory (NREL)
Address:	1617 Cole Blvd. Golden, CO 80401-3393
Telephone:	303-275-3837
Email:	Darlene_Steward@nrel.gov

Sponsor(s)

Name:	Fred Joseck
Organization:	DOE/EERE/HFCIT
Telephone:	202-586-7932
Email:	Fred.Joseck@ee.doe.gov

Period of Performance

Start:	October 2004
End:	May 2008

Project Description

Type of Project:	Analysis
Category:	Hydrogen Fuel Pathways

Methodology/Approach:	Material and energy balances in ASPEN Plus; Installed equipment costing based on grass roots estimate of commercial offering

Models Used:	H2A Production Model

Timeframe Studied:	2005

Products/Deliverables

	Description: Spreadsheet Analysis Publication Title: Current (2005) Hydrogen from Natural Gas without CO2 Capture and Sequestration Publisher: National Renewable Energy Laboratory Author Name(s): Steward, Darlene http://www.hydrogen.energy.gov/h2a_prod_studies.html Publication Date: May 2008

Notes/Comments:	Natural gas is fed to the plant from the pipeline at a pressure of 450 psia. The gas is generally sulfur-free, but odorizers with mercaptans must be cleaned from the gas to prevent contamination of the reformer catalyst. The desulfurized natural gas feedstock is mixed with process steam to be reacted over a nickel based catalyst contained inside of a system of high alloy steel tubes. The reforming reaction is strongly endothermic, and the metallurgy of the tubes usually limits the reaction temperature to 1400-1700°F. The flue gas path of the fired reformer is integrated with additional boiler surfaces to produce about 700,000 lb/hour steam. Of this, about 450,000 lb/hour is superheated to 450 psia and 750°F, to be added to the incoming natural gas. Additional steam from the boiler is sent off-site. After the reformer, the process gas mixture of CO and H2 passes through a heat recovery step and is fed into a water gas shift reactor to produce additional H2. The Pressure Swing Adsorption (PSA) process is used for hydrogen purification, based on the ability to produce high purity hydrogen, low amounts of CO and CO2 and ease of operation. Shifted gas is fed directly to the PSA unit where hydrogen is purified up to approximately 99.6%.

Notes/Comments:

Natural gas is fed to the plant from the pipeline at a pressure of 450 psia. The gas is generally sulfur-free, but odorizers with mercaptans must be cleaned from the gas to prevent contamination of the reformer catalyst. The desulfurized natural gas feedstock is mixed with process steam to be reacted over a nickel based catalyst contained inside of a system of high alloy steel tubes. The reforming reaction is strongly endothermic, and the metallurgy of the tubes usually limits the reaction temperature to 1400-1700°F. The flue gas path of the fired reformer is integrated with additional boiler surfaces to produce about 700,000 lb/hour steam. Of this, about 450,000 lb/hour is superheated to 450 psia and 750°F, to be added to the incoming natural gas. Additional steam from the boiler is sent off-site. After the reformer, the process gas mixture of CO and H2 passes through a heat recovery step and is fed into a water gas shift reactor to produce additional H2. The Pressure Swing Adsorption (PSA) process is used for hydrogen purification, based on the ability to produce high purity hydrogen, low amounts of CO and CO2 and ease of operation. Shifted gas is fed directly to the PSA unit where hydrogen is purified up to approximately 99.6%.

Date Last Updated: 10/01/2008