Absorption and purification method: It is realized by utilizing the physical and chemical absorption characteristics of organic amine solutions (primary, secondary, tertiary, sterically hindered, etc.) and carbon dioxide, that is, under pressure and normal temperature in the absorption tower, an absorption reaction occurs with carbon dioxide in the biogas to decarbonize and purify methane, and the absorption rich liquid undergoes a reverse desorption reaction under reduced pressure and heating conditions in the regeneration tower, releasing highly purified carbon dioxide gas, At the same time, the regeneration of the rich liquid has the ability to reabsorb carbon dioxide, thereby realizing the continuous decarbonization and purification of methane in the absorption tower, and allowing the decarbonization liquid to undergo continuous absorption and regeneration cycles.

变压吸附提纯法：利用吸附剂(如分子筛等)对二氧化碳的选择性吸附特点, 即在吸附剂上二氧化碳相对其他气态组分有较高的分离系数, 来达到对沼气中二氧化碳进行脱除的目的。在吸附过程中，原料气在加压条件下其中的二氧化碳被吸附在吸附塔内，甲烷等其他弱吸附性气体作为净化气排出，当吸附饱和后将吸附柱减压甚至抽成真空使被吸附的二氧化碳释放出来。为了保证对气体的连续处理要求，变压吸附法至少需要两个吸附塔, 也可是三塔、四塔或更多。

Pressure swing adsorption purification method: Utilize the selective adsorption characteristics of adsorbents (such as molecular sieves) for carbon dioxide, which means that carbon dioxide has a high separation coefficient compared to other gaseous components on the adsorbent, to achieve the purpose of removing carbon dioxide from biogas. During the adsorption process, carbon dioxide in the feed gas is adsorbed in the adsorption tower under pressure, and other weakly adsorbing gases such as methane are discharged as purified gas. When the adsorption is saturated, the adsorption column is depressurized or even evacuated to release the adsorbed carbon dioxide. In order to ensure the continuous treatment requirements for gases, the pressure swing adsorption method requires at least two adsorption towers, which can also be three, four, or more.

低温冷凝提纯法：利用二氧化碳液化温度高的特点，通过低温作用使沼气中的二氧化碳被液化，甲烷组分作为不凝气以提纯产品气排出。为了降低运行能耗，通常采用回热技术将剩余冷量进行回收。

Low temperature condensation purification method: Utilizing the characteristics of high liquefaction temperature of carbon dioxide, the carbon dioxide in biogas is liquefied by low-temperature action, and the methane component is discharged as non-condensable gas to purify the product gas. In order to reduce operating energy consumption, regenerative technology is usually used to recover the remaining cooling capacity.

膜分离提纯法：利用不同气体组分在压力驱动下通过膜的渗透性作用的不同来实现的，通常情况下二氧化碳的渗透速度快，作为快气以透过气排出，甲烷的渗透速度慢，作为慢气以透余气形式获得提纯产品气。在工程中，为了提高甲烷气的浓度，常采用多级膜分离工艺。

Membrane separation and purification method: It is realized by using different gas components under pressure driving through different membrane permeability effects. Generally, carbon dioxide has a fast permeation rate, and as a fast gas, it is discharged through gas, while methane has a slow permeation rate, and as a slow gas, it is obtained as purified product gas in the form of permeable residual gas. In engineering, multi-stage membrane separation processes are often used to improve the concentration of methane gas.

沼气提纯项目我们采用膜分离技术，以沼气为原料，经过压缩、过滤、膜分离和增压单元，通过合理的流程设计，将沼气提纯制备为符合标准的CNG产品。

In the biogas purification project, we use membrane separation technology, using biogas as raw material, through compression, filtration, membrane separation, and pressurization units, and through reasonable process design, to purify biogas into CNG products that meet the national standard "Compressed Natural Gas for Vehicles" (GB18047).

膜分离技术是利用薄膜材料对各种气体的渗透率不同来实现气体分离的一种技术。膜分离的主要驱动力是截留侧(中空纤维内部)和渗透侧(中空纤维外部)中间的压力差。这个差值越高，通过渗透膜的气体比重越大。气体的渗透速率取决于膜材料的溶解度和扩散速率。不同的气体在膜材料中的渗透速率不同。

Membrane separation technology is a technology that utilizes the different permeability of membrane materials to various gases to achieve gas separation. The main driving force for membrane separation is the pressure difference between the interception side (inside the hollow fiber) and the permeation side (outside the hollow fiber). The higher the difference, the greater the specific gravity of the gas passing through the osmotic membrane. The gas permeation rate depends on the solubility and diffusion rate of the membrane material. Different gases have different permeation rates in membrane materials.

更多的关于沼气提纯问题或者详细的内容，请进入我们公司的网站：网站中会有很多的内容仅供参考。

For more information on biogas purification issues or detailed content, please visit our company's website: There will be a lot of content on the website for reference only.