Quadrogen - Biogas Clean-up System

1. Condensation
   Feed is cooled to condense water and other contaminants such as siloxanes and volatile organic compounds. Condensed liquids are then separated from the gas stream to remove a large proportion of the contaminants without using any adsorbent media.
2. Conversion
   Dry feed gas is treated with a hydrogen-assisted catalytic process that converts the broad spectrum of problematic organic contaminants into a known and easily captured set of species.
3. Capture
   Specially-formulated sorbent media beds, specifically tailored to the known species produced by the conversion stage, capture the remaining contaminants.
4. Polishing
   Biogas is further polished of trace-level contaminants to the parts-per-billion level in a final chemisorption step. This unique polishing step provides reliable protection of downstream equipment, even in the event of spikes in the input gas contaminant levels.

Quadrogen’s Integrated Biogas Upgrading Systems remove contaminants and inert gas from biogas so it can be upgraded as biomethane for gas pipeline injection or vehicle fuel.

Quadrogen benefits:

• Creates pipeline-quality biomethane, with oxygen reduced to parts-per-billion levels
• Removes contaminants such as halides, VOCs, sulfur species and siloxanes
• Creates cleaner biomethane, allowing biogas upgrading plants to achieve maximum performance and longevity.

Using Quadrogen’s technology, raw biogas from waste water treatment plants, landfills and agricultural digesters can be cleaned and used to power reciprocating engines, gas turbines, and fuel cells. Electricity and heat generated by these systems can be sold or used on-site, creating a source of renewable energy. Our modular clean-up systems are easily scalable, and contaminant removal characteristics can be tailored to meet customer requirements at minimum cost.

Quadrogen Benefits:

Saves money by protecting power plant downstream components:

• no siloxane-induced deposits in combustion chambers and heat exchangers
• reduces exhaust system corrosion due to H₂S
• reduces oil degradation and subsequent wear
• increases life of catalytic converters by removing catalyst poisons.

Reduces emissions:

• H₂S and SO_X emissions nearly undetectable
• NO_x emissions reduced with improved performance of NO_x catalytic converter.

Quadrogen clean-up solutions can be used on gases other than biogas.

Here are two possible applications we have in development:

Associated Gas Conversion to Natural Gas

Substantial amounts of ethane and other non-methane hydrocarbons (NMHCs) are often present in shale gas or associated gas. In many cases, sending the gas to an ethane separation facility is not economically feasible. NMHCs can become a serious problem when they increase the overall gas BTU content beyond what is permitted by natural gas specifications.

Quadrogen can provide gas clean-up systems for efficiently converting NMHCs into methane, so natural gas output is increased while simultaneously removing the high-BTU problem.

Syngas Clean-up

Syngas often contains a number of contaminants, but tars are by far the biggest challenge. If not removed, tars adhere to ducts, heat exchangers, catalysts, and other components, reducing system performance and greatly increasing maintenance costs.

Quadrogen can provide gas clean-up systems to remove these tars in a reliable and cost effective manner. Once the tars have been removed, Quadrogen can also provide modules for removing other contaminants, such as chlorides and sulfur species.