Hydrometallurgy最新文献

{"title":"Enhancement of gold extraction by citric acid-assisted microwave roasting of Carlin-type gold ores and sulfide/thiosulfate leaching","authors":"Tiantian Wu ,&nbsp;Zhihui Shen ,&nbsp;Zhenwu Shi ,&nbsp;Jianlong Wang ,&nbsp;Yueqin Qiu ,&nbsp;Song Mao","doi":"10.1016/j.hydromet.2024.106410","DOIUrl":"10.1016/j.hydromet.2024.106410","url":null,"abstract":"<div><div>The occurrence of most gold in an encapsulated state often results in poor extraction efficiency, and efficient pretreatment is the key to effective gold recovery from Carlin-type gold ores. This study investigated the enhancement of citric acid (CA) assisted microwave (MW) roasting on gold extraction from Carlin-type gold ores by sulfide/thiosulfate leaching, primarily analyzing in-situ phase transformation, microstructure characterization, and the thermal decomposition behavior of solids. The results show that gold extraction increases significantly with increasing CA dosage, furnace temperature, and roasting time when heated by MW, reaching a maximum of 87.7% at a CA dosage of 2% and a temperature of 500°C for 60 min in the presence of air. Moreover, extraction is significantly higher with CA than without CA at roasting temperatures below 300°C. The phase transition of gold-bearing pyrite is controlled mainly by temperature when heated by MW without CA, resulting in surface oxidation at 300°C, with significant oxidation at 400°C, and complete transformation into Fe₂O₃ and SO₂ at temperatures over 500°C. Interestingly, CA and its decomposition products of CO₂ and H₂O induce the generation of unstable intermediates at 100°C, such as FeCO₃, FeC₂₁H₂₁O₇, and FeOOH. The decomposition of these intermediates at higher temperatures results in the rapid formation of a hematite layer with developed pores at 300°C, which provides more diffusion channels for SO₂ and O₂, producing coral-like porous hematite particles. Both number of pores and the pore size are larger at 500°C. The combined effect of MW and CA enhances exposed gold content over 70% which in turn increases gold extraction. This work provides significant insights into the enhancement process of gold extraction of CA-assisted MW roasting.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"231 ","pages":"Article 106410"},"PeriodicalIF":4.8,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient recovery of organic phase from crud in solvent extraction unit of Sarcheshmeh copper complex in Iran by powerful water-absorbent reagents","authors":"Mohammad Anary-Abbasinejad ,&nbsp;Zahra Manafi ,&nbsp;Fatemeh Zamani ,&nbsp;Parisa Salarizadeh ,&nbsp;Mehri Shahhoseini ,&nbsp;Fereshteh Vahedi ,&nbsp;Seyed Ali Seyedbagheri","doi":"10.1016/j.hydromet.2024.106408","DOIUrl":"10.1016/j.hydromet.2024.106408","url":null,"abstract":"<div><div>The formation of stable multi-phase emulsions (crud) is a serious problem in almost all commercial solvent extraction (SX) plants. Crud is a mixture of organic and aqueous phases, air, and organic or inorganic solid particles, often found to distribute itself randomly throughout the separating phases of SX plants. Crud formation is encountered in almost all SX units in metal extraction plants. It causes the loss of solvent and thus increases the process costs. Therefore, the removal of crud and recovery of the expensive organic phase including diluent and extracting reagents from it is of great importance. In this research, the applicability of a range of powerful water absorbent reagents was studied for the recovery of organic phase from the crud formed in copper extraction/electrowining unit of Sarchashmeh copper complex (IRAN). The reagents included gypsum, carbomer, sodium polyacrylate, sodium sulfate, magnesium sulfate and calcium chloride. The results showed that gypsum, carbomer and sodium polyacrylate are effective additives which let the organic phase to be recovered with up to 95 % yield. To ensure that gypsum does not cause a negative effect on the copper loading and stripping of the recovered solvent, the extraction/stripping properties of the organic phase separated with gypsum was compared with the organic phase separated by centrifugation without additives. Surface tension analysis of the gypsum-recovered organic phase also confirmed its suitability for recovery of organic phase from crud. Finally, the calcium content of gypsum-recovered organic phase was measured and compared with that of the organic phase separated by centrifugation without any additive.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"231 ","pages":"Article 106408"},"PeriodicalIF":4.8,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The combined leaching of copper, gold and uranium in chloride solutions. II. Concentrate leach tests","authors":"M. Nicol ,&nbsp;K. Ye ,&nbsp;N. Garrard","doi":"10.1016/j.hydromet.2024.106407","DOIUrl":"10.1016/j.hydromet.2024.106407","url":null,"abstract":"<div><div>This study of the simultaneous leaching of copper, gold and uranium from a flotation concentrate is aimed at establishing the conditions that could be applied in a possible heap leach process that would recover all three metals (plus silver, if present) in a single step. The results obtained in this study confirm the results obtained in Part I (Nicol et al., 2024) that enhanced rates for leaching of chalcopyrite from flotation concentrates from two different sources can be obtained in acidic chloride solutions in the presence of chlorate ions. The measurements of the solution potentials during leaching with chlorate are similar to those obtained previously and confirm that chlorine generated by the chlorate-chloride reaction is the active oxidant.</div><div>Uranium is dissolved even in the absence of chlorate by iron(III) as the oxidant. The latter is re-generated by reaction of iron(II) with chlorate. The dissolution of gold requires higher potentials, and it is only leached when the potential approaches 1.0 V in concentrated chloride solutions. At low chloride concentrations (1 M), gold is not dissolved because of apparent passivation.</div><div>An electrochemical study of the behaviour of gold in chloride solutions in the presence of sulfide ions has shown that the passivation is probably the result of the formation of a layer of Au₂S on the gold surface at low potentials before the addition of chlorate to the leach solutions i.e., before the generation of sufficient chlorine concentrations. At potentials above about 0.95 V Au₂S is unstable being oxidised to AuCl₂⁻ and elemental sulfur thereby eliminating passivation.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"231 ","pages":"Article 106407"},"PeriodicalIF":4.8,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The combined leaching of copper, gold and uranium in chloride solutions. I. Chalcopyrite","authors":"M. Nicol ,&nbsp;K. Ye ,&nbsp;N. Garrard","doi":"10.1016/j.hydromet.2024.106406","DOIUrl":"10.1016/j.hydromet.2024.106406","url":null,"abstract":"<div><div>In a study (Part II) aimed at the simultaneous heap leaching of copper (predominantly chalcopyrite), gold and uranium from an ore, it was found that this could be achieved using chlorate as the oxidant in chloride solutions. As a result, a more detailed study has been made using electrochemical and batch leach tests on pure chalcopyrite electrodes under typical heap leach conditions.</div><div>The use of chlorate at moderately low concentrations has shown that enhanced rates of dissolution of chalcopyrite can be maintained over periods up to 4 days at ambient temperatures in acidic chloride solutions. The rate of dissolution is enhanced at higher acid concentrations. The rate in the presence of chlorate does not appear to depend on the iron(III) (and presumably the copper(II)) concentration.</div><div>The observed rates are significantly greater than those predicted for oxidative dissolution from the electrochemistry and the mixed potential model. An alternative non-oxidative mechanism has been revisited to account for this difference.</div><div>A preliminary measurement has been made of the kinetics of the oxidation of hydrogen sufide and iron(III) by low concentrations of chlorine produced by reaction of chlorate with chloride ions. These reactions are rapid, and theory shows that they would support the proposed non-oxidative mechanism.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"231 ","pages":"Article 106406"},"PeriodicalIF":4.8,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scaling analysis of electrodeposited copper and the influence of a modified polysaccharide on surface roughness","authors":"Jeffrey L. Shepherd ,&nbsp;Karl Torman ,&nbsp;Michael S. Moats ,&nbsp;Joseph Bauer ,&nbsp;Eduard Guerra","doi":"10.1016/j.hydromet.2024.106405","DOIUrl":"10.1016/j.hydromet.2024.106405","url":null,"abstract":"<div><div>The influence of a commercially available modified polysaccharide (HydroStar®, Chemstar Chemical Products) on the roughness of short-term and small-scale copper electrodeposits was investigated using Atomic Force Microscopy (AFM), linear scan profilometry and scaling analysis. Copper was deposited on a 316L stainless steel cathode at 40 °C and 300 A m⁻² from an electrolyte containing 40 g L⁻¹ Cu²⁺, 170 g L⁻¹ H₂SO₄, 1.5 g L⁻¹ Fe³⁺, 15 mg L⁻¹ Cl⁻ and either 0, 10, 50 or 100 mg L⁻¹ of HydroStar. Copper deposits produced between 15 and 25 min were imaged using AFM and 2D linear scan profilometry was used to gather surface features of copper samples produced in the range of 120 and 240 min. Scaling analysis was applied to quantify the surface characteristics of limiting roughness (δ) and critical length (L_C) from which δ/L_C was computed and related to the aspect ratio of surface features. All copper deposits showed a general rise in δ and L_C with deposition time but the growth rates decreased when HydroStar was included in the electrolyte indicating that the additive lowers the vertical height of surface features as well as their widths. Furthermore, copper deposits were more consistently produced in the presence of HydroStar and, for a given value of limiting roughness, had surface features with wider base than those created in the absence of the additive. The results show that the modified polysaccharide acts to create smooth copper deposits by generating surface features with lower aspect ratios.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"231 ","pages":"Article 106405"},"PeriodicalIF":4.8,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142421714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation of V2O5 using Pb5(VO4)3OH recovered from Bayer vanadium sludge through H2SO4 pre-treatment, H2O2 leaching, V5O12∙6H2O and V10O24∙12H2O precipitation and oxidative roasting at 400 °C","authors":"Changda Zhang,&nbsp;Qiusheng Zhou,&nbsp;Yilin Wang,&nbsp;Leiting Shen,&nbsp;Guihua Liu,&nbsp;Tiangui Qi,&nbsp;Zhihong Peng,&nbsp;Xiaobin Li","doi":"10.1016/j.hydromet.2024.106404","DOIUrl":"10.1016/j.hydromet.2024.106404","url":null,"abstract":"<div><div>Bayer vanadium sludge (BVS), discharged during the Bayer alumina production, is a promising secondary resource for the supply of vanadium. Previous vanadium extraction process involving Pb₅(VO₄)₃OH precipitation by PbSO₄, H₂SO₄ and (NH₄)₂SO₃ leaching, (NH₄)₂S₂O₈ oxidation followed by ammonium vanadate precipitation, suffered from large amounts of reagent consumption and discharge of ammonia-containing waste. In this study, a cleaner and cost-efficient process based on H₂SO₄ pre-treatment, H₂O₂ leaching, hydrolytic precipitation, and preparation of V₂O₅ through oxidative roasting was proposed to reduce reagent consumption and waste. Results show that the maximum vanadium leaching efficiency reached 99.7 % under the most suitable conditions of H₂SO₄ pre-treatment with H₂SO₄/Pb₅(VO₄)₃OH molar ratio of 6.5, pulp density of 250 g/L at 90 °C for 4 h followed by H₂O₂ leaching with H₂O₂/V molar ratio of 3.0 at 15 °C for 10 min. Furthermore, 96.5 % of vanadium was precipitated in the forms of V₅O₁₂∙6H₂O and V₁₀O₂₄∙12H₂O by heating the leach liquors to 100 °C for 60 min, followed by the oxidative roasting at 400 °C for 2 h to prepare V₂O₅ product with a purity of 99.2 %, with only H₂O as a by-product. This research provides new insights into vanadium extraction in a cleaner, cost-efficient, and sustainable industrial process which saves 147.4 $/t Pb₅(VO₄)₃OH.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"231 ","pages":"Article 106404"},"PeriodicalIF":4.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solvent extraction of titanium(IV) from orthophosphoric acid media using Aliquat-336/kerosene and stripping with nitric acid","authors":"Ahmed A. Galhoum,&nbsp;Basma T. Mohamed,&nbsp;Shaimaa S. Abdulmoteleb,&nbsp;Said I. Mohamady,&nbsp;Nagwa I. Falila","doi":"10.1016/j.hydromet.2024.106403","DOIUrl":"10.1016/j.hydromet.2024.106403","url":null,"abstract":"<div><p>Titanium extraction from acidic solutions was investigated using Aliquat-336, considering factors like acid type and concentration for leaching, diluent type for solvent extraction, equilibration time, extractant concentration, phase ratio, and temperature. Kerosene exhibited superior performance as an aliphatic diluent for Aliquat-336 compared to other utilized diluents. The extraction efficiency was inversely proportional to the dielectric constant of the diluents. The quantitative Ti(IV) extraction efficiency from phosphoric acid (6 M H₃PO₄) leach liquor of ilmenite and rutile achived 98 % at room temperature (298 K) in 10 min after mixing with 0.1 M Aliquat-336 dissolved in kerosene at a phase volume ratio of 1:1 (Aq:Org). The exothermic extraction process occurred spontaneously. The proposed extraction mechanism using Aliquat-336/kerosene involves ion-pair association of the extractant with a Ti(IV) complex, confirmed by FTIR spectroscopy. The Ti(IV) ions were effectively stripped using HNO₃ (3 M) with an aqueous:organic phase volume ratio of 1:1 at 25 °C after a contact time of 10 min in each step. The Aliquat-336/kerosene efficiently tested for Ti(IV) recovery from acidic Abu-Ghalaga ilmenite and rutile leachate. The findings indicate that, the phosphate medium is highly efficient in extracting Ti(IV), even with low concentration of Aliquat-336 in kerosene, especially in comparison to the impurities such as Fe, Cr, and Al. The EDX, XRD, and wet chemical analyses of the final product after the hydrolysis of stripped Ti(IV) from samples originating from the Abu-Ghalaga area and rutile samples, confirmed the formation of high-purity TiO₂ (predominantly anatase phase). The SEM results showed particles with a regularly spherical structure and uniform size.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"231 ","pages":"Article 106403"},"PeriodicalIF":4.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142244150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Selective extraction of silver from jarosite residues produced in the zinc hydrometallurgical process using thiourea under acidic conditions: Kinetic analysis and leaching optimization","authors":"Mary C. Nolasco ,&nbsp;Israel Rodríguez ,&nbsp;Javier E. Vilasó ,&nbsp;Mizraim U. Flores ,&nbsp;Thangarasu Pandiyan ,&nbsp;Emmanuel J. Gutiérrez ,&nbsp;Javier Aguilar ,&nbsp;Martín Reyes ,&nbsp;Iván A. Reyes","doi":"10.1016/j.hydromet.2024.106396","DOIUrl":"10.1016/j.hydromet.2024.106396","url":null,"abstract":"<div><p>In this work, an industrial hazardous jarosite residue produced in the zinc hydrometallurgical process containing silver was used to evaluate the feasibility of using thiourea (Tu) for silver leaching under acidic conditions in the presence of oxalate (C₂O₄²⁻ ion denoted as Ox²⁻). The shrinking core kinetic model (SCKM) was applied to evaluate the effect of variables on the reaction rate. The chemical reaction of H₃O⁺ with the jarosite surface was the controlling stage. The results of batch experiments revealed that silver extraction is influenced by various factors in the descending order: pH &gt; T (temperature) &gt; [Tu] (thiourea concentration) &gt; [Ox²⁻] (oxalate concentration). The extraction efficiency of Ag was 98 % at high levels of both T and [H₂SO₄], although a higher [Tu] was required. High Tu consumption was associated with the stability of Tu due to the presence of Fe³⁺ and Cu²⁺ ions leached along with Ag⁺, which affect the redox potential catalyzing Tu oxidation. Temperature is the most effective variable with a reaction rate constant of k_exp = 1.1 min⁻¹ at 60 °C, but it causes a decrease in silver extraction to 92.5 %. The kinetic parameters were obtained using the SCKM; furthermore, the experimental results were statistically validated through a surface response experimental design.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"231 ","pages":"Article 106396"},"PeriodicalIF":4.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142162160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on ultrasonic assisted intensive leaching of germanium from germanium concentrate using HCl/NaOCl","authors":"Mingyuan Rao ,&nbsp;Hongying Xia ,&nbsp;Yingjie Xu ,&nbsp;Guiyu Jiang ,&nbsp;Qi Zhang ,&nbsp;Yongtao Yuan ,&nbsp;Libo Zhang","doi":"10.1016/j.hydromet.2024.106385","DOIUrl":"10.1016/j.hydromet.2024.106385","url":null,"abstract":"<div><p>Ultrasonic radiation is widely used in the enhancement of leaching process with outstanding advantages in leaching efficiency. In this study, a germanium concentrate was leached with NaClO and the influence of factors such as ultrasound power and oxidant addition on the leaching efficiency of germanium from the concentrate were investigated. The leaching efficiency of germanium reached 96.8% at the initial concentration of hydrochloric acid of 8 mol/L, the oxidant dosage of 1.5 g/L NaClO, the liquid-solid volume/mass ratio of 6 mL/g, the ultrasonic power density of 13.3 W/cm³, and the stirring speed of 300 rpm for 30 min at 60 °C. The leaching efficiency was 4.50% higher at a shorter leaching time and lower temperature, than that of the conventional process, which was mainly attributed to the ultrasonic multiple effects and NaClO. Meanwhile, NaClO can effectively oxidize As(III) into non-volatile As(V), remove arsenic in germanium, facilitate the subsequent distillation, improve the leaching efficiency, and be more environmentally friendly.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"230 ","pages":"Article 106385"},"PeriodicalIF":4.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142130174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of non-reactive solute transport models for the evaluation of fluid flow in packed beds with implications for heap leaching practice","authors":"Michael D. Odidi ,&nbsp;Marijke A. Fagan-Endres ,&nbsp;Susan T.L. Harrison","doi":"10.1016/j.hydromet.2024.106395","DOIUrl":"10.1016/j.hydromet.2024.106395","url":null,"abstract":"&lt;div&gt;&lt;p&gt;This study investigated the effects of mean particle size fraction, bottom particle size, particle porosity and wettability on solution scale preferential flow behaviour via step input tracer tests in drip irrigated, narrowly and mixed-sized beds under steady state fluid flux. Nine solute transport models were used to quantify this behaviour reflected in the residence time distribution (RTD) profiles. Four were empirical models: three compartmental model configurations (CM-1, CM-2, CM-3) and tanks-in-series (TIS) model. The remainder five models were semi-empirical: advection dispersion (AD), piston exchange (PE), piston exchange - diffusion variant (PE-D), piston dispersion and exchange (PDE) and piston dispersion and exchange - diffusion variant (PDE&lt;img&gt;D). The model fit results showed that the mono-porosity TIS, AD and CM-2 models were the worst performers, while the dual porosity PDE and novel PDE-D models achieved the lowest average error values across the various systems. Higher levels of particle wettability coupled with capillary effects produced peculiar RTD curves that were relatively more difficult for the mono-porosity models to simulate. The model parameters investigated included the longitudinal dispersion coefficient (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;D&lt;/mi&gt;&lt;mi&gt;ds&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;), dead to total volume fraction (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mi&gt;D&lt;/mi&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;msub&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;), dynamic to total saturation fraction (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;msub&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;), overall mass transfer coefficient (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/msub&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;) and maximum diffusional pore length (&lt;span&gt;&lt;math&gt;&lt;mi&gt;X&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;). The results showed that an increase in the average particle size within the beds led to higher &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mi&gt;D&lt;/mi&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;msub&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;D&lt;/mi&gt;&lt;mi&gt;ds&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mi&gt;X&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; values, but lower &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;msub&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/msub&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; values. These indicate an overall increase in solution scale preferential flow behaviour. Decreased capillary suction and connectivity between particle pores and inter-particle voids were deemed responsible for the results. Higher levels of particle porosity acted as a buffer against these effects. Overall, the results highlight the benefit of the addition of fines (0.1–1 mm particles) during the agglomeration process in heaps to help reduce solution scale preferential flow behaviour and increase liquid hold-up. This is more necessary when the ore has low to moderate levels of porosity (surface area: &lt;span&gt;&lt;math&gt;&lt;mo&gt;&lt;&lt;/mo&gt;&lt;/math&gt;&lt;/span&gt;2 m&lt;sup&gt;2&lt;/sup&gt;/g) and will also increase the modelling options availab","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"230 ","pages":"Article 106395"},"PeriodicalIF":4.8,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142090503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}