Research On The Desorption Characteristics Of Ammonia-water Decarburization Rich Liquid Under The Combined Action Of Nanoparticles And Magnetic Field

The burning of fossil fuels emits large amounts of CO₂,causing global climate change and exacerbating the greenhouse effect.Greenhouse gas emission reduction has become a hot issue in the world.Ammonia method decarburization technology with ammonia water as absorbent has the advantages of low cost,high absorption capacity,not easy degradation,no corrosion to equipment,etc.It is one of the most promising CO₂ emission reduction technologies.In this paper,the effects of nanoparticles and external magnetic field on CO₂desorption performance of ammonia water decarbonization rich solution were studied.The main work is as follows:On the semi-continuous bubbling tower set up by ourselves,the experimental study of CO₂ desorption by ammonia water decarburization rich solution was firstly carried out.The effects of reaction temperature,concentration of initial solution and load degree of CO₂ on desorption rate and desorption ratio of CO₂ were studied.At the same time,according to the curve of CO₂volume flow rate changing with time,the reaction process can be divided into three stages:the rapidly rising stage,the rapidly falling stage and the slowly falling stage.By comparing the proportion of desorption in each stage,it can be seen that the rapidly falling stage and the slowly falling stage account for more of the three stages.The results show that the desorption rate and desorption ratio of CO₂ increase with the increase of temperature,concentration of initial solution and load degree of CO₂.70?is the best desorption temperature,70?,the initial solution concentration 1.0 mol/L,CO₂bear load level 1.0,CO₂ desorption rate is 0.0004 mol/?L?s?,the desorption rate of 57.1%.Secondly,the effect of nanoparticles and magnetic field on the performance of desorption of CO₂ in ammonia water decarbonization rich solution was studied.The effects of particle type,particle amount and magnetic field on the desorption rate and desorption ratio of CO₂ were studied.The results showed that the addition of Al₂O₃ nanoparticles promoted the desorption process of the rich solution,and the average desorption rate and the total desorption ratio in the rapidly decreasing phase of CO₂ increased by 2.9%and 5.6%respectively after the addition of particles compared with that without addition.Adding Fe₃O₄ nanoparticles inhibited the desorption process of the rich solution,and the total desorption ratio of CO₂ decreased by 5.4%.The obvious agglomeration of Fe₃O₄ particles in the solution led to the inhibition of desorption of the rich solution.The addition of magnetic field can further enhance the desorption process of rich liquid.The average desorption rate and total desorption ratio in the CO₂ rapid decline stage are 10.8%and 8.5%higher than that without the addition of particles and magnetic field under the combined action of 40m T magnetic field and 0.1g/LAl₂O₃ particles,and 2.8%and 2.9%higher than that with only added particles.The effects of reaction temperature,initial solution concentration and CO₂ loading degree on CO₂ desorption rate and CO₂ desorption ratio under the combined action of nanoparticles and magnetic field were studied.The desorption rate and desorption ratio of CO₂ increased with the increase of reaction temperature,the increase of initial solution concentration and the increase of CO₂ load.The promoting effect of particles and magnetic field is more obvious when the reaction temperature is higher,the initial concentration of solution is lower,and the load degree of solution CO₂ is higher.The effects of particle and magnetic field on CO₂ mass transfer were studied.Adding0.1g/L Al₂O₃ nanoparticles alone can increase the total mass transfer coefficient by 13.2%.Adding 0.1g/L Al₂O₃ nanoparticles and 40m T magnetic field can increase the total mass transfer coefficient by 21.0%.The particle and magnetic field promoted the interphase mass transfer process of CO₂,thus increasing the desorption rate and desorption ratio of CO₂.