Title: HYBRID SULFUR RECOVERY PROCESS FOR NATURAL GAS UPGRADING

Abstract

This first quarter report of 2002 describes progress on a project funded by the U.S. Department of Energy (DOE) to test a hybrid sulfur recovery process for natural gas upgrading. The process concept represents a low cost option for direct treatment of natural gas streams to remove H{sub 2}S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day. This process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both on-shore and offshore applications. CrystaSulf{sup SM} (service mark of CrystaTech, Inc.) is a new nonaqueous sulfur recovery process that removes hydrogen sulfide (H{sub 2}S) from gas streams and converts it into elemental sulfur. CrystaSulf features high sulfur recovery similar to aqueous-iron liquid redox sulfur recovery processes, but differs from the aqueous processes in that CrystaSulf controls the location where elemental sulfur particles are formed. In the hybrid process, approximately 1/3 of the total H{sub 2}S in the natural gas is first oxidized to SO{sub 2} at low temperatures over a heterogeneous catalyst. Low temperature oxidation is done so that the H{sub 2}S can bemore » oxidized in the presence of methane and other hydrocarbons without oxidation of the hydrocarbons. The project involves the development of a catalyst using laboratory/bench-scale catalyst testing, and then demonstration of the catalyst at CrystaTech's pilot plant in west Texas. In a previous reporting period tests were done to determine the effect of hydrocarbons such as n-hexane on catalyst performance with and without H{sub 2}S present. The experiments showed that hexane oxidation is suppressed when H{sub 2}S is present. Hexane represents the most reactive of the C1 to C6 series of alkanes. Since hexane exhibits low reactivity under H{sub 2}S oxidation conditions, and more importantly, does not change the SO{sub 2} selectivity, we can conclude that the C1-C6 hydrocarbons should not significantly interfere with the oxidation of H{sub 2}S into SO{sub 2}. During this quarter the effect of aromatic compounds were also found to have no effect on catalyst performance. This report gives the results of testing using contaminants from the pilot plant site.« less

Authors:

Srinivas, Girish; Gebhard, Steven C; DeBerry, David W

Publication Date:

Mon Apr 01 00:00:00 EST 2002

Research Org.:

National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV, and Albany, OR (United States)

Sponsoring Org.:

US Department of Energy (US)

OSTI Identifier:

799757

Report Number(s):

FC26-99FT40725-06
TRN: US200220%%669

DOE Contract Number:  

FC26-99FT40725

Resource Type:

Technical Report

Resource Relation:

Other Information: PBD: 1 Apr 2002

Country of Publication:

United States

Language:

English

Subject:

03 NATURAL GAS; ALKANES; AROMATICS; CATALYSTS; HEXANE; HYDROCARBONS; HYDROGEN SULFIDES; IRON; METHANE; METRICS; NATURAL GAS; OPERATING COST; OXIDATION; SULFUR