Optimization of Coagulation Process of Coke Microparticles for Filtration and Gravity Separation Systems

Document Type : Research Article

Author

Chemical Engineering Department, Chemical and Petroleum Engineering Research Institute, Chemistry and Chemical Engineering Research Center of Iran, Tehran, I.R. IRAN

Abstract

Remarkable amounts of coke microparticles are discarded along with the effluent of decoking and olefin units and their separation methods have not been studied as the environmental pollutants. In this work for the first time the appropriate flocculant was determined for the separation of coke microparticles and then, the optimized conditions of simultaneous-experimental coagulation/flocculation process were determined based on the maximum amounts of sedimentary particles. After that, using the hypothesis of extreme agglomeration, the optimal conditions were calculated based on the maximum efficiency of filtration of gravity separation of coagulated particles. A set of purposeful experiments were performed based on the response surface method and using FeSO4, Al2(SO4)3 and FeCl3 coagulants at concentrations of 10, 15 and 20 ppm and with cationic (Zetafloc 7563), natural (Besfloc K300N) and anionic (Megafloc 3045PWG) poly acrylamide flocculants at concentrations of 3, 5 and 7 ppm in solutions with pH levels of 5, 7 and 9. According to the diameter criteria of sedimentary particles (d>21μm) the uniformity/curvature coefficients were obtained for the optimal conditions of particle coagulation. The results revealed that according to the negative surface charge of coke particles the maximum number of precipitable particles is formed with a yield of 96% using iron chloride(III) coagulant (8ppm), anionic polyacrylamide flocculant (2ppm) at pH=6. Moreover, based on the uniformity/curvature coefficients the results showed the priority of iron sulfate(II) as coagulant for enhancement of filtration efficiency since the diameter distribution of coagulated coke particles maximizes the porosity of filter-cake, the operation time of filter and the volume of accumulated cake. While the type of coagulant has no effect on the gravity-based separation efficiency of coagulated coke particles. Based on the results, the optimum ratio of coagulant to flocculant concentrations were determined to be 3 and less than 3 (1.5–3) for filtration and gravity separation systems.

Keywords

Main Subjects


[1] Pourabdollah K., Self-Assembled Monolayers, the Agglomeration Binders of Pyrolytic Coke Fines, Powder Technol., 339: 130–138 (2018).
[2] Aladejebi O.A., Monaghan B.J., Reid M.H., Panhuis M., Longbottom R.J., Metallic Iron Effects on Coke Analog Carbon Bonding and Reactivity, Steel Res. Int., 88: 1700039 (2017).
[3] Case P.A., Wheeler M.C., DeSisto W.J., Effect of Residence Time and Hot Gas Filtration on the Physical and Chemical Properties of Pyrolysis Oil, Energy Fuel, 28: 3964–3969 (2014).
[4] Weber S., Briens C., Berruti F., Chan E., Gray M., Stability of Agglomerates Made from Fluid Coke at Ambient Temperature, Powder Technol., 209: 53–64 (2011).
[5] Pietsch W., An Interdisciplinary Approach to Size Enlargement by Agglomeration, Powder Technol., 130: 8–13 (2003).
[6] Merzouk B., Gourich B., Madani K., Vial C., Sekki A., Removal of a Disperse Red Dye from Synthetic Wastewater by Chemical Coagulation and Continuous Electrocoagulation. A Comparative Study, Desalination, 272: 246–253 (2011).
[8] Simate G.S., Iyuke S.E., Ndlovu S., Heydenrych M., The Heterogeneous Coagulation and Flocculation of Brewery Wastewater using Carbon Nanotubes, Water Res., 46: 1185–1197 (2012).
[9] Duran A., Monteagudo J.M., Sanmartin I., Garcia-Pena F., Coca P., Treatment of IGCC Power Station Effluents by Physico-Chemical and Advanced Oxidation Processes, J. Env. Manag., 90: 1370–1376 (2009).
[10] حسنوند ا.، هاشم‎آبادی س.ح.، شبیه‌سازی CFD انتقال نیوماتیک ذره‌های پرپلیمر و محاسبه سرعت ته‎نشینی آن‌ها، نشریه شیمی و مهندسی شیمی ایران، (1)30: 43 تا 52 (1390).
[11] Teh C.Y., Budiman P.M., Shak K.P.Y., Wu T.Y., Recent Advancement of Coagulation–Flocculation and its Application in Wastewater Treatment, Ind. Eng. Chem. Res.55: 4363–4389 (2016).
[12] Verma A.K., Dash R.R., Bhunia P., A Review on Chemical Coagulation/Flocculation Technologies for Removal of Colour from Textile Wastewaters, J. Env. Manag., 93: 154–168 (2012).
[14] Wang L., Gao Q., Li Z., Wang Y., Improved Removal of Quinoline from Wastewater using Coke Powder with Inorganic Ions, Processes, 8: 156 (2020).
[15] Yang Z., Zhuoyue M., Zhihua L., Sitong W., Synthesis and Application of Itaconic Acid Water-Coke Slurry Dispersant, Mater. Sci. Forum., 896: 167–174 (2017).
[16] He Q., Wang R., Wang W., Xu R., Hu B., Effect of Particle Size Distribution of Petroleum Coke on the Properties of Petroleum Coke–Oil Slurry, Fuel, 90: 2896–2901 (2011).
[18] Kusnin N., Syed M.A., Ahmad S.A., Toxicity, Pollution and Biodegradation of Acrylamide – A Mini Review, JOBIMB, 3: 6–12 (2015).
[19] Van Dijk-Looijaard A., Van Genderen J., Levels of Exposure from Drinking Water, Food Chem. Toxicol., 38: 37–42 (2000).
[20] Ghafaria S., Abdul Azizb H., Hasnain Isac M., Zinatizadeh A.A., Application of Response Surface Methodology (RSM) to Optimize Coagulation–Flocculation Treatment of Leachate using Poly-Aluminum Chloride (PAC) and Alum, J. Hazard.  Mater., 163: 650–65 (2009).
[21] Godymchuk A., Papina I., Karepina E., Kuznetsov D., Lapin I., Svetlichnyi V., Agglomeration of Iron Oxide Nanoparticles: pH Effect is Stronger than Amino Acid Acidity, J. Nanopart. Res., 21: 208 (2019).
[22] Al-Gebory L., PinarMengüç M., The effect of pH on particle agglomeration and optical properties of nanoparticle suspensions, J Quant Spectrosc Radiat Transfer, 219: 46–60 (2018).
[23] Saritha V., Srinivas N., Srikanth Vuppala N.V., Analysis and Optimization of Coagulation and Flocculation Process, Appl. Water Sci., 7: 451–460 (2017).
[24] Yukselen M.A., Gregory J., The Effect of Rapid Mixing on the Break-Up and Re-Formation of Flocs, J. Chem. Technol. Biot., 79: 782–788 (2004).
[27] Priyatharishini M., Mokhtar N.M., Study on the Zeta Potential Effect of Artocarpus Heterophyllus Natural-based Coagulant in Wastewater Treatment, IOP Conf Ser: Mater Sci Eng, 991: 012094 (2020).
[29] Bensadok K., Benammar S., Lapicque F., Nezzal G., Electrocoagulation of Cutting Oil Emulsions using Aluminium Plate Electrodes, J. Hazard. Mater., 152: 423–430 (2008).
[30] Ersoy B., Tosun I., Günay A., Dikmen S., Turbidity Removal from Wastewaters of Natural Stone Processing by Coagulation/Flocculation Methods, Clean, 37: 225–232 (2009).
[31] Gregory J., O'Melia C.R., Fundamentals of flocculation, Crit. Rev. Environ. Contr., 19: 185–230 (1989).