Research On The Strengthening Of Wet Desulfurization Of Phosphate Rock Slurry

With the increasing efforts of the government to control the SO₂ pollution,many phosphorus chemical companies have considered to transform the desulfurization system under the premise of not changing its own flue gas desulfurization system.The wet desulfurization with phosphate ore slurry has lower cost and convenient raw materials,while the desulfurization efficiency of wet desulfurization of phosphate ore slurry is unstable,the stability of desulfurization with phosphate ore slurry is enhanced by different strengthening methods,and some methods with industrial application prospects are explored.In the additive screening experiment,the best nitrate additive,metal oxide additive,and organic additive is ferric nitrate,the best is manganese dioxide,and adipic acid.The optimum addition ratio of ferric nitrate,manganese dioxide and adipic acid,4%,6%,2%respectively.The desulfurization efficiency of these three additives under different SO₂ concentrations was studied.When the reaction was carried out for 120 min,the enhanced desulfurization effect of manganese dioxide on the phosphate slurry was the best.The ferric nitrate to phosphate ore slurry,followed by ferric nitrate,and the adipic acid has the worst effect on the enhanced desulfurization of the phosphate ore slurry.In addition,the effects of single reaction factors such as different reaction temperatures,different agitator speeds,different gas flow rates and different pH on the desulfurization of phosphate ore slurry were analyzed.Experiments showed that the optimum temperature of enhanced desulfurization is 25°C for ferric nitrate,25°C for manganese dioxide,and 45°C for adipic acid respectively.It is recommended to control the stirring speed within 1500r/min and the gas flow rate between 0.2 L/min and 0.3 L/min.The optimum pH for desulfurization of phosphate ore slurry by the three desulfurization additives is 8,6,and 6 respectively.In addition,a composite experimental study was conducted on the selected additives,the results show that the best effect on the desulfurization of phosphate ore slurry is 5%adipic acid+5%sodium citrate,and the desulfurization efficiency is 74.07%when the reaction is 120 min.Moreover,when the reaction was carried out for 120 min with 2%adipic acid+2%ferric nitrate,2%ferric nitrate+6%compared with no additive,the three composite additives of manganese dioxide enhance the desulfurization efficiency of the phosphate ore slurry desulfurization system above 38%.Ultrasonic treatment and hydrogen peroxide enhancement were selected for research.Among them,ultrasonic treatment conditions such as different ultrasonic power,different ultrasonic treatment time and different ultrasonic treatment temperatures was considered to strengthen the desulfurization of phosphate ore slurry.The hydrogen peroxide enhancement is mainly studied from the aspects of addition ratio and reaction temperature.Under the ultrasonic power of different ultrasonic,the desulfurization strengthening effect of phosphate ore slurry is best when the ultrasonic power is 50 W.Under the different ultrasonic treatment time,the best time is 1 min,.Under different ultrasonic reaction temperatures,the effect of enhanced desulfurization of phosphate ore slurry was best when the ultrasonic treatment temperature was 40°C.Under different hydrogen peroxide addition ratios,this research suggests that the optimal addition ratio of H₂O₂ is 0.03%in the subsequent experiments.At different reaction temperatures,the decomposition rate of hydrogen peroxide is obviously accelerated,and the overall desulfurization efficiency fluctuates.It is recommended to select a reaction temperature of 25°C.It is recommended to select a gas flow rate as between 0.2 L/min and 0.3 L/min.