Gas Technology Products (GTP)
Processes to Remove H2S from Landfill Gas (LFG)

Gas Technology Products offers a line-up of cost-effective, environmentally-friendly, and powerful H2S elimination systems that are adaptable to your LFG treatment needs. To help determine the right process for your needs, use the following formulas:

[(SCFM gas flow) x (ppmv H2S)]/8225 = lb/day sulfur
[(Nm3/hour gas flow) X (ppmv H2S)] / 29671 = kg/day sulfur

LO-CAT® and MINI-CAT™—Water-based H2S removal processes for LFG with higher H2S concentrations.  Typically, LO-CAT is used for removing 1,000–10,000 kg of sulfur per day as H2S; MINI-CAT™ for removing 200–1,000 kg (440–2,200 lb) sulfur per day as H2S.  The patented LO-CAT (liquid oxidation catalyst) process uses an iron chelate solution to oxidize the H2S to elemental sulfur and water. The iron chelate solution is then continuously regenerated using air, resulting in much lower operating costs than non-regenerable scavengers. The elemental sulfur product can be used for agricultural applications—so it is not a waste product requiring disposal.

Different configurations are employed to yield better than 99.9% H2S removal. In the Mobile Bed Absorber configuration, moderately low pressure gas streams are contacted counter-currently with LO-CAT solution using spherical balls to aid in mixing. Venturi contactors are used for low pressure, high volume gas streams where the required sulfur removal efficiency is lower. In all configurations, the elemental sulfur is separated, the LO-CAT solution is regenerated with air in a separate Oxidizer vessel, and the solution is circulated back to the Absorber.

The MINI-CAT™ process treats smaller H2S loads using the same chemistry as LO-CAT. However, MINI-CAT is especially attractive and cost-effective for many LFG applications as a modular option with lower capitol cost than LO-CAT. MINI-CAT units are pre-fabricated, skid-mounted, have a small footprint, and offer expanded flexibility for variable LFG flows and H2S concentrations.  

Sulfur-Rite® System—Solid media H2S and mercaptan removal system designed to treat LFG with minimal capital investment. This system removes up to 200 kg of sulfur per day. Using single vessel or two vessel configurations, the LFG flows downward through a granular media where sulfur compounds react irreversibly to form iron pyrite (FeS2). Treated gas typically contains less than 1 ppmv total sulfur. The solid media must be replaced when spent and requires disposal.

Eliminator® Liquid Scavenger System—Water-based H2S and mercaptan removal system designed to treat LFG with minimal capital investment. This system removes up to 200 kg of sulfur per day using amine resin-based Eliminator® chemicals that are safe and do not contain formaldehyde. Typically resulting in less than 4 ppmv total sulfur in the product gas, the liquid scavenger can either be injected directly into a gas stream, or a packed bed or bubble tower can be used. The spent liquid requires disposal.

MINI-CAT® Brochure