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With the growing demand for renewable energy, biogas, as a combustible gas with a high calorific value, is receiving increasing attention. The purified biogas can meet various application requirements, including use as household gas, heat and electricity generation in thermal power plants, fuel for vehicles, and integration into natural gas networks. Lvyuan Environmental Protection utilizes PSA (Pressure Swing Adsorption) purification technology, which relies on pressure changes to enable adsorption and regeneration. This technology allows for the effective extraction of methane from biogas, bringing it to quality standards suitable for use as natural gas, while also removing carbon dioxide, thereby facilitating the extraction and utilization of gaseous energy sources. The core advantages of PSA (Pressure Swing Adsorption) technology are operation at normal temperatures, a simple process flow, a high degree of automation, and the ability to achieve continuous separation and purification of gases. Today, I will introduce to you the working principle, technical advantages, and multi-scenario applications of this technology. I. Working principle of PSA purification technology: PSA purification technology is a gas separation method based on pressure changes. The gas coming from the desulfurization system is compressed by a compressor to 0.6 MPa; this biogas then enters a cold dryer to have its moisture removed. After that, it goes into a gas-liquid separator, and from there it enters a methane decarburization purification unit whose operation timing is preset. The components in the feed gas that are easily adsorbed, such as CO2, are absorbed by the adsorbent, while those that are not easily adsorbed, such as CH4, emerge as the product gas. This gas is sent through a pressure regulator and a precision filter to remove any solid particles, before being fed into the pipeline network. The high-boiling-point impurity components remain adsorbed in the adsorbent. The PSA purification technique uses pressure reduction or evacuation for desorption, that is, a portion is separated by reducing the pressure through pressure equalization. To ensure thorough regeneration of the adsorbent, after the pressure equalization process is complete, vacuum pumping is used to further reduce the partial pressure of impurities; once the evacuation process is finished, the regeneration of the adsorbent is complete. After the adsorbent regeneration is completed, the pressure in the adsorption tower is -0.07 to -0.09. To ensure the adsorption efficiency and stabilize system pressure, it is necessary to pressurize the adsorption towers to reach the specified adsorption pressure; meanwhile, the effective components (CH4) present in the dead spaces of other adsorption towers are recovered, and pressure balance is achieved between the towers in a pair-wise manner. Then, the product gas is used to raise the pressure in the adsorption tower to the adsorption pressure; at this point, the preparation for adsorption in the tower is complete, and the next cycle can begin. Through the above process, continuous, stable, and safe operation of the methane purification unit is achieved. II. Advantages of PSA purification technology: (1) High separation efficiency and high product purity – It can effectively remove impurities such as carbon dioxide or small amounts of hydrogen sulfide from biogas, increasing the purity of methane to over 95%, thereby meeting the standards required for biogas to be integrated into utility networks or for use in applications that demand high purity. (2) Operation at normal temperature and low pressure results in lower energy consumption, keeping operating costs under control. Compared to traditional methods such as chemical absorption, no large amounts of chemical reagents are required; the main energy consumption comes from the pressurization and depressurization processes of the adsorption tower, hence the low energy use. (3) The equipment has a relatively simple structure, making it easy to operate and maintain. It can be shipped in a skid-mounted format, which is environmentally friendly and convenient. This technology offers flexible operation and simple control, allowing it to meet the needs of various applications. (4) It enables fully automatic continuous operation, features a high degree of automation, requires minimal manual intervention, reduces labor costs, and facilitates equipment maintenance. (5) Environmentally friendly, with no secondary pollution such as wastewater generation. The entire process relies primarily on physical adsorption; there is no need to use corrosive or toxic chemical reagents, and no wastewater or waste residues containing pollutants are produced. Thus, it has a minimal impact on the environment and meets the environmental requirements of clean energy. III. Multiple applications of PSA purification technology: (1) Production of vehicle-grade natural gas: The purified biomethane can be compressed into CNG or liquefied into LNG, to be used directly as a fuel for vehicles. It can replace traditional natural gas and reduce carbon emissions in the transportation sector. (2) Integration into the natural gas network: When the purity of biogas meets **natural gas standards, it can be fed into the urban natural gas network to be used by residents and industrial users for heating, cooking, or manufacturing, thereby enabling the recycling of energy. (3) Energy supply in the industrial sector: Purified biomethane can be used as fuel for industrial boilers and furnaces, or to power heating and power generation equipment in industrial processes. (4) Distributed energy systems: Near sources of biogas such as landfills and large-scale farms, biomethane can be produced using PSA purification technology. By pairing this with small gas turbines or generators, distributed power or heating systems can be established to meet the energy needs of surrounding industrial parks and communities, thereby reducing energy transmission losses. (5) Integration with environmental protection and solid waste treatment: This technology is often used in conjunction with biogas systems at landfills, livestock farms, and sewage treatment plants, converting the biogas that would otherwise be released directly into clean energy, thereby offering both environmental benefits and economic advantages. IV. Future Outlook: GreenSource Environmental Protection is well aware that only through continuous innovation can it remain at the forefront in the highly competitive environmental protection industry. In the future, the development of PSA biogas purification technology will focus more on improving efficiency and reducing costs. GreenSource Environmental Protection looks forward to working with you to contribute more to the preservation of clean environments and green landscapes.