Preparation Of Blue-coke-based Activated Coke And And Its Desulfurization Performance Research

The activated coke flue gas desulfurization technology is a resource-based dry desulfurization technology that not only removes SO₂ from flue gas,but also removes nitrogen oxides,dioxins,heavy metals and HCl,and has products that are dry.Activated coke is a desulfurizer for activated coke flue gas desulfurization technology and is a key material for determining desulfurization performance and efficiency.It does not produce the advantages of secondary pollution such as waste water residue.In this paper,waste blue coke and direct coal liquefaction residue produced by low-temperature metamorphic coal in low-temperature dry distillation are used as the main raw materials,and activated coke is prepared by carbon dioxide activation.The raw material ratio,carbonization conditions and activation conditions are taken into account to study the properties of molding activated coke.The influence law of the method,the best preparation parameters of flue gas desulfurization activated coke was obtained;the flue gas desulfurization experiment was carried out by using self-made activated coke,and the desulfurization performance of activated coke was systematically studied.This research method is an effective way to improve the added value and comprehensive utilization of waste blue carbon,and also provide some theoretical and technical support for the later activated coke flue gas desulfurization process.The following main conclusions were obtained through research:?1?In the preparation process of activated coke,the main factors of different raw materials,carbonization conditions?carbonization temperature and carbonization time?and activation conditions?activation temperature,activation time and carbon dioxide flow rate?on the activated coke strength and iodine adsorption value are mainly studied.The characterization of the shaped activated coke was carried out by means of SEM,BET,FT-IR and XRD.The results show that the coal liquefaction residue pyrolysis process will produce a large number of cohesive colloids,further increasing the strength of the activated coke.The mass ratio of direct liquefaction residue of coal to blue coke is 2:3,carbonization temperature is 600?,carbonization time is 60 min,activation temperature is 850?,activation time is 90 min,and carbon dioxide flow rate is 60mL/min.The activated coke prepared under the conditions had an iodine adsorption value of 401 mg/g and a compressive strength of 573.2 N.BET analysis showed that the specific surface area of activated coke was 239.00m²/g,the total volume of micropores was 0.089cm³/g,and the average pore diameter was 2.390nm.SEM analysis shows that the active coke surface is more dense and the pore distribution is more uniform;infrared analysis showed The content of direct liquefaction residue of coal increases,and the content of activated coke surface functional groups also increases.?2?Using a fixed-bed reactor,using self-made activated coke as adsorbent for flue gas desulfurization experiments,investigating factors such as SO₂ concentration at the inlet of the bed,different bed heights,water vapor concentration,O₂ concentration and adsorption temperature.The effect of adsorption performance.The results show that at lower temperature,SO₂ and O₂ have competitive adsorption on the surface of activated coke;if the concentration of water vapor is too high,a water film will be formed on the surface of activated coke,which will hinder the adsorption of SO₂ by activated coke.The initial concentration of SO₂ is 700ppm,the height of activated coke bed is 12cm,the adsorption temperature is 80?,the oxygen concentration is 9%,and the concentration of water vapor is 8%.The removal of SO₂ by activated coke is better,and the desulfurization rate reaches 95%.Based on the experimental data obtained,the adsorption model of activated coke desulfurization was established.The experimental values agree well with the simulated values.