Methane Purification
Methane Purification
The Challenge
The customer is an important manufacturer of industrial and rare gases and needs to purify methane from a natural source for an electronic application. They want to obtain a highly pure methane product and find the best and most cost-effective separation technology for this application.
The typical feed composition is:
- N2: 0.6 %
- CO2: 1000 ppm vol.
- Ethane: 6.0 %
- Propane: 2 %
- Iso-Butane: 0.9 %
- Methane: 90 %
- Oxygen: 800 ppm
Our Solution
The proposed system consists of two main sections:
- A pre-treatment section that removes water and carbon dioxide by adsorbing them on molecular sieves in a parallel double bed system. One bed remains in service, while the other undergoes regeneration using waste hot gas after separating pure CH4.
- A cryogenic distillation section for the separation of other impurities, which is composed of two distillation columns:
Plant Design Data:
- Methane Feed: 15 Nm3/h
- Outlet methane composition:
- CH4: 99.9995 %
- O2: < 0.5 ppm
- H2O: < 1 ppm
- N2: < 4 ppm
- CO2: < 0.5 ppm
- Other impurities: < 0.5 ppm
Main Utilities Consumption:
- Liquid Nitrogen: 45 kg/h
- Electric power: 5 kW
The Results
Innovative Solution – The Polaris plant offered an integrated system combining multiple technologies to solve the problem of removing several different types of contaminating compounds for premium methane purification.
Safe and Reliable – A guaranteed safe and reliable solution was provided for regeneration of the molecular sieves – even in the presence of highly flammable streams such as methane.
Improved Product Quality & Value – Overall, when a client is interested in reaching very pure products, the Polaris plant can upgrade product quality, thus improving resale value.
