Biogas H2S Scrubbers

Hydrogen sulfide (H₂S) is a toxic, corrosive gas naturally present in biogas, landfill gas, and digester gas. Even at low concentrations, it causes rapid corrosion of engines, turbines, heat exchangers, and piping systems — dramatically shortening equipment life and increasing maintenance costs.

Why removal is essential:

• Equipment protection: H₂S corrodes metals and forms sulfuric acid when combusted, destroying downstream equipment
• Emissions compliance: SO₂ produced from burning H₂S is a regulated pollutant in most jurisdictions
• Safety: H₂S is immediately dangerous to life at concentrations above 100 ppm
• Energy value: Clean gas performs more efficiently in power generation and upgrading applications

CRA offers a full range of H₂S removal technologies, each suited to different gas compositions, flow rates, and H₂S concentrations:

• Chemical H₂S Scrubbers: Liquid-phase absorption using caustic or iron-based chemistry — ideal for high H₂S concentrations
• Biological H₂S Scrubbers: Microorganism-based oxidation — low operating cost, no chemical consumption
• Carbon Activated Dry Scrubbers: Adsorption on impregnated activated carbon — compact footprint, no liquid waste
• Bio-Regenerative Chemical Scrubbers: Combines biological and chemical processes for continuous, high-efficiency removal

Our engineers evaluate your specific gas stream to recommend the most cost-effective technology for your application.

The right scrubber depends on several interrelated factors that CRA evaluates during the proposal stage:

Key selection criteria:

• Inlet H₂S concentration: Ranges from hundreds to tens of thousands of ppm — determines technology type
• Gas flow rate: Total volumetric flow (SCFM or Nm³/h) drives equipment sizing
• Required outlet purity: Target ppm determines scrubbing stages and chemistry
• Available utilities: Water supply, power, and chemical delivery access
• Site footprint: Space constraints may favour compact dry or biological systems
• Operating budget: Balance between capital cost and ongoing chemical/maintenance costs

CRA's scrubber systems routinely achieve 99%+ H₂S removal efficiency. Our chemical scrubbers can reduce H₂S from levels as high as 30,000 ppm down to less than 1 ppm in a single pass.

Typical performance by technology:

• Chemical scrubbers: <1 ppm outlet, >99.9% removal
• Biological scrubbers: <50 ppm outlet, up to 99% removal
• Activated carbon: <1 ppm outlet for moderate inlet concentrations

Performance guarantees are provided based on your specific gas composition and operating conditions.

Standard lead times range from 12 to 20 weeks depending on system complexity, customization requirements, and current production schedule.

CRA manufactures all systems at our own facilities, giving us direct control over quality and delivery timelines. We do not rely on third-party fabricators, which reduces delays and ensures consistent build standards.

Expedited delivery options are available for urgent projects — contact our team to discuss your timeline requirements.

Yes. CRA has successfully delivered and commissioned H₂S scrubber systems across multiple countries including India, Southeast Asia, the Middle East, and Africa.

International project support includes:

• Engineering: Full process and mechanical design with local regulatory compliance
• Manufacturing: Fabrication at CRA's own facilities with international shipping coordination
• Installation supervision: CRA engineers on-site to oversee installation and commissioning
• After-sales support: Remote diagnostics and field service availability