Wartsila Biogas Solutions – Gas Upgrading System
Puregas Solutions is Now Part of Wartsila
Wärtsilä is a global leader in smart technologies and complete lifecycle solutions for the marine and energy markets. By emphasising sustainable innovation, total efficiency and data analytics, Wärtsilä maximises the environmental and economic performance of the vessels and power plants of its customers.
Wärtsilä Biogas Solutions approaches biogas upgrading and liquefaction utilizing the unique Puregas biogas upgrading process to recover over 99.9% of the available methane contained in raw biogas, maximizing biomethane yields and customer revenues with very low operational costs. The biomethane is suitable for natural gas grid injection, or for liquefaction using the mini scale MR liquefaction process.
The Puregas process recovers more than 99.9% of the biomethane present in the raw biogas. The plant separates the CO2 from the biogas by a process of chemical adsorption. The selective organic solvents used in this process are so efficient that the end product can contain more than 99% methane and is suitable for vehicle fuel or to be injected into the natural gas grid. As the final product is so pure there is often no requirement to enrich with propane. Unlike other technologies the Puregas process is highly tolerant of changes to the raw gas composition resulting from changes in feedstocks.
Technology Strengths, Weaknesses and Critical Indicators
Anaerobic Digester Associated Technology:
NOTE: There are several technology types that are used as part of an integrated manure management system that includes an anaerobic digester and are not applicable to manure management in other cases. The impact of these technologies on the critical indicators are represented as those of an entire anaerobic digester system.
- Long usable life and can be run reliably
- Creates energy and generates environmental credits
- Requires proper preparation of the feedstock
- Requires other technologies for energy utilization
- Requires other technologies for digestate handling
- Proper feeding & system monitoring is required to avoid system downtime
- Proven technology for odor control, GHG reduction and pathogen reduction
Wartsila's has not done very many U.S. digester projects thus far, but they are part of a significant project at Threemile Canyon Farms where the original electric energy system was converted to an Renewable Natural Gas (RNG) system in late 2020.
The Threemile Canyon Farms digester sequesters around 136,000 metric tons per year of CO2. This is equivalent to the annual greenhouse gas emissions from 28,875 passenger vehicles, or CO2 emissions from 16,285 homes’ energy consumption, or carbon sequestration by 160,061 acres of forest land.
1. OPERATIONAL HISTORY