Technology Research Of Biogas Dry Desulfurization And Pressure Swing Adsorption

Biogas is a flammable gas that microorganisms in anaerobic fermentation organic matter to come into being, is a mixture of some kinds of gases.The main constituent is methane (CH4) accounted for about50%-75%,carbon dioxide (CO2) accounted for about20%-45%,hydrogen sulfide (H2S) and so on.Larger CO2in biogas can decrease biogas’thermal value.I-^S is an acidic toxic gases with a pungent smell,has causticity,is harmful to the human body.But also for the environment, equipment, pipeline and instrumentation.Contamination and corrosion effects.o when the use of biogas the CO2and H2S removal is of great significance for industrialization of biogas utilization.The purpose of this test is the removal of H2S and CO2from biogas. Purified biogas. The method of getting rid of hydrogen sulfide is dry flue gas desulfurization method.Because the craft of dry flue gas desulfurization method has a few good features of no secondary pollutant in the aspect of overing,cost,operation,regulation,maintaining,by-product and so on.this test use dry flue gas desulfurization method.Getting rid of CO2uses pressure swing adsorption method.Comparing whit traditional method of membrane adsorption,absorption, Variable temperature adsorption,has a few good features of high purity,simple equipment,low operation costs.So this test chooses dry flue gas desulfurization method at lost.This test is divided into four parts,the first part is the choice of dry desulfurization reagent and decarbonization adsorbent,the second part is the design of carbon removal system and its control system,the third part is study of pressure swing adsorption flow,last is the study of gas desulfurization and decarbonization process.Desulphurizer selection. Biogas purification in the purification process, in order to prevent removal of carbon adsorbent for poisoning, so before decarbonization need for desulfurization of biogas. This test uses a dry flue gas desulfurization method, select the iron oxide desulfurizer, two towers of experimental device for manual desulfurization devices,Test content for the use of manual tower desulphurization plant experiments, iron oxide hydroxides desulfurization effect better drawn from the test results, and the device when using the iron oxide desulfurizer, best reloading time is70h.Choice of adsorbent. Introduces several main three adsorbents for the removal of carbon dioxide, ZGA-high-intensity activated alumina, and13X-APG air separation-specific molecular sieve5A molecular sieve, and determination of three kinds of adsorbent for separation of methane and carbon dioxide effects, specific tests, under different conditions of adsorption pressure (0.1 ～0.8MPa),Using gas chromatography determination of three kinds of sorbent adsorption Tower outlet port of the content of the gases through pilot drew the following conclusions:got5A molecular sieve under the0.7MPa, obtain the highest concentrations of methane,90.26%,So this test selecting5A molecular sieve as pressure swing adsorption agent.And its optimum working pressure is0.7Mba.Pressure swing adsorption device and control system design. This appliance designed for laboratory experiments are designed to remove carbon dioxide two towers of PSA decarbonization unit, the device consists of two towers of pressure swing adsorption system and electric control system, through the electric controlling system of pressure swing adsorption process of looping control.Decarbonization technology of pressure swing adsorption device is the PSA decarbonization process parameters to be determined, namely, adsorption, desorption time, pressure-filled time and time determination at first.To5A molecular sieve for adsorption agent, respectively on typical of technology parameter for determination obtained this two Tower transformer adsorption device of best technology parameter is in0.7Mba, buck points for0.1MPa, intake flow for251·min-1, adsorption tower of filling pressure time for230s, adsorption time for220S, pressure time for8s, pumping vacuum time for520s, at this time obtained CH4concentration Supreme.This article is design and study of desulfurization and decarbonization.Through process design in the last part.First of dry desulfurization through dry flue gas desulfurization system and air pump pressure continued into PSA unit for decarbonization processing,through which is designed to achieve the purpose of gas desulfurization and decarbonization.