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1

Exploring the characterization, liberation and flotation response of a Nigerian low-grade copper ore

Nheta Willie, Ola-Omole Omoyemi O.

Journal of Sustainable Mining

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2023

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Vol. 22, iss. 1

20--32

EN

This study explores the characterization, liberation and flotation response of low-grade copper ore from Anka area, Zamfara state Nigeria. The ore was crushed, milled and sieved in accordance with BS 410 standard. It was characterized with XRD, XRF, SEM-EDS and AAS. Froth flotation was carried out with varying %solids, pH, retention time and collector dosages using SEX and sodium oleate. Particle size distribution of the ore shows its economic liberation between -150 and +106 µm while 80% passing corresponds to 175.7 µm using the Gaudin Schuhmann equation. However, according to metallurgical balance calculation, 63 µm proved to have the highest metal content. Identified peaks of the copper ore by XRD revealed the presence of pyrite and chalcopyrite as the major mineral content at 47 and 36%, respectively, while other elements were present in traces. XRF shows Fe and Cu as the major elements and others in traces. Morphology, according to SEM-EDS, revealed that Fe is the major impurity while the presence of Cu and S confirmed chalcopyrite is present in the ore minerals. AAS shows an average of 25.87% Cu and 32% Fe in the ore. Optimum recoveries of copper were recorded at 30% solids, pH of 8, 30 minutes retention time. The highest recovery of 95.94% was recorded with SEX at 0.25 mol/dm3, while recoveries were lower with PAX, the highest recovery being 33% at 0.20 mol/dm3. 0.25 mol/dm3 of SEX recorded the highest yield and enrichment ratio of 40.38 and 2.38, respectively.

2

Increase in the Free Finely-Dispersed Gold Recovery in the Flotation Cycle

Toktar Gulmira, Bakrayeva Akbota, Abdyldayev Nurgali, Banks Graig E., Kubaizhanov Alibek

Journal of Ecological Engineering

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2023

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Vol. 24, nr 1

115--119

EN

This article presents the results of a comparative study for the increase in the free finely dispersed gold recovery from the gold-bearing ore produced in a deposit in Kazakhstan. The following minerals were identified in the sample under X-ray phase analysis: chalcopyrite and pyrite, as well as in a finely disseminated state in silicate minerals. Gold in the ore is present mainly (40.09%) in the free form under the results of phase analysis. Flotation tests of ore beneficiation were performed in FML-1 and FML-3 flotation machines with chamber volumes of 1.0 and 3.0 liters. A flotation combined concentrate with a gold content of 15.3 g/t was obtained (concentrate yield 9.45%), with gold recovery into concentrate 82.79% in the optimal mode: the grind of 90% in the class -0.071 mm; consumption of reagents: C7 foaming agent – 30 and 60 g/t, sodium butyl xanthate – 60 and 120 g/t; the time of the main flotation – 10 minutes, the control flotation – 7 minutes, at pH = 9. Flotation tailings contained 0.33 g/t of gold. The recovery showed a fairly high 84.42% (yield of the total concentrate 20.93%) with the gold content of 7.1 g/t with the use of a sulfidizing agent (Na2S) and additional dispersion of the pulp at pH = 9.0. A gold-bearing concentrate was obtained containing 4.0 g/t Au at a fineness of -0.05 mm and 6.8 g/t Au at a fineness of +0.05 mm. The beneficiation of the pulp with a fineness of +0.05 mm gave the recovery into the final concentrate equal to 89.94%.

3

A Study on the Recovery of Zinc and Pig Iron from Byproducts after Steelmaking Dust Treatment

Wang Jei-Pl

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 1

205--208

EN

In this study, a research was conducted to recover metallic zinc and pig iron and to improve the purity and the recovery rate through a reduction process for zinc and iron in the byproducts that are generated after steelmaking dust treatment. As the result of the calcination, it was confirmed that Cl (6.06%) and K (3.37%) decreased to Cl (2.75%) and K (0.22%), respectively. For the zinc powder that was recovered with reaction temperature of 1100°C, reaction time of 4 hours, and argon gas of 1L/min as the optimal conditions. The measurement for the purity of zinc was 99.8% and the recovery rate was 92.14%. The melt reduction for recovering pig iron from the residue was reacted under reaction temperature of 1600°C, flux composition (CaO:SiO2) of 1:1, and reducing agent infusion ratio (residue: C) of 14:1, and the pig iron was measured to have a purity of 87.7% and a recovery rate of 91.81%.

4

Recycling of Polyethylene Terephthalate (PET) Bottles in the Logistics Supply Chain – Overview

Zając Paweł, Ejdys Stanisław, Dzik Renata

Rocznik Ochrona Środowiska

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2022

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Tom 24

439--456

EN

A great deal of packaging made of PET is observed in logistics supply chains, and the article is mainly concerned with food – bottles. Implementing the EU’s “zero-waste” guidelines implies action on the part of producers of packaging and food for B2C distribution to find new solutions to enable the above-mentioned stakeholders in the logistics supply chain to balance the business mentioned above parties – taking into account environmental protection. The article discusses the tasks and possibilities under the above conditions of a new type of “RECYCLER” companies, which, at the end of the life of PET packaging, i.e. after the foodstuffs in PET bottles have been consumed, produce a recyclate and return it to reproduction. In several journals, including, e.g. (Połednik et al. 2016, Topiarzová et al. 2011), respecting good recycling practices – there is an ongoing discussion on the sense of introducing reusable packaging, deposits, etc. This article discusses the barriers to recovery in a multi-level plastics recovery system, with specific reference to the operation of a PET bottle recycling line, and presents a pre-verified concept for a method to increase the efficiency of separating PET bottles from the plastics fraction in a multi-level waste separation system.

5

LCD panels bioleaching with pure and mixed culture of Acidithiobacillus

Willner Joanna, Fornalczyk Agnieszka, Saternus Mariola, Sedlakova-Kadukova Jana, Gajda Bernadeta

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 1

15--23

EN

The influence of pure and mixed culture of A. ferrooxidans and A. tiooxidans as well as different pulp density (1 and 2%) of LCD panels on the In and Sn bioleaching efficiency was investigated. Pulp density is one of the factors affecting the metals extraction efficiency during biological leaching. It has been shown that lower pulp density results in higher indium and tin dissolution. The A. ferrooxidans bioleaching system showed better metal extraction results than A. thiooxidans, especially for tin, indicating the special role of iron and A. ferrooxidans in tin recovery. The highest leaching rate of both indium (94.7%) and tin (98.2%) was obtained using iron and sulfur medium inoculated with mixed bacteria and a pulp density of 1% w/v.

6

Estimation of grade and recovery in the concentration of barite tailings by the flotation using the MLR and ANN analyses

Deniz Vedat, Umucu Yakup, Deniz Orcun T.

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 150646

EN

This study aimed to find optimal models in a comparative framework to estimate the recovery and grade of barite concentrate obtained from the rougher flotation of the barite tailings. Therefore, firstly, the effect of four operating parameters (flotation time, pH, collector dosage, and depressant dosage) on the rougher flotation of the barite tailings containing 37.23% BaSO4 was experimentally investigated. Secondly, two models called the multivariable linear regression (MLR) and the artificial neural network (ANN) were used for the estimation of the recovery and grade of the barite concentrate for the rougher flotation optimization. The R2 values found from the MLR and ANN models were 0.828 and 0.995 for the concentrate recovery, and 0.977 and 0.960 for the barite concentrate grade, respectively. In the comparison of the models determined, it was found that the ANN model expressed quite well than the MLR models, especially for the recovery of the rougher concentrate.

7

Beneficiation and concentration of feldspar from syenite ore in Medina, Saudi Arabia for industrial utilization

Gougazeh Mousa

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 155056

EN

The objective of this study was to reduce the contents of iron and titanium heavy minerals of feldspar from Medina syenite ore by a combination of magnetic separation and flotation to obtain the commercial scale of feldspar concentrate for glass and ceramics industries. For the first time, a process flowchart was provided in the light of this study to produce a high-quality K-feldspar product from syenite ore, which meets the requirements of feldspar for glass and ceramics productions. The results reflect that the best performance separation of iron and titanium contents was produced by a dry magnetic separator at 16.000 gauss. The produced feldspar concentrate by magnetic separation yielding 0.54% Fe2O3 with 87% Fe2O3 recovery and 0.57% TiO2 with 16% recovery. The flotation tests were performed on the non-magnetic fraction of the syenite ore. In this stage, the most effective for removal of Fe2O3 and TiO2 from syenite ore was obtained at a 300 g/ton dosage of a mixture of Aeromine 3030C and Aeromine 801 + Aeromine 825 as a collector in an acidic medium (pH 3). The final feldspar concentrate with 0.07% Fe2O3 and 0.06%TiO2 grades was obtained with 89% Fe2O3 recovery and 86% TiO2 recovery. The commercial scale of feldspar concentrate from syenite ore can meet the desired specification of grades 1 and 2 for glass, porcelain, and ceramics industries.

8

Assessing benthic macroinvertebrates in relations to environmental variables and revitalisation works

Czerniawska-Kusza Izabela

Ecological Chemistry and Engineering. S

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2022

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Vol. 29, nr 1

99--110

EN

Macroinvertebrates of two ex-manor ponds located in Chroscina, Opole Region (Poland) were studied from 2015 to 2018 to investigate their community composition and diversity and evaluate the heterogeneity of communities on spatial and temporal scale referring to environmental variables and revitalisation work. A total of 32 taxa were recorded (at the family level, except Oligochaeta), 13 of which were Ephemeroptera, Odonata and Trichoptera, recognised as sensitive groups in lentic ecosystems. Macroinvertebrate richness and diversity varied considerably, especially in spring and summer. It was found that habitat heterogeneity influenced benthic invertebrates more than basic water parameters. However, the environmental variables together accounted for only 38 % of the observed variations. Thus, other factors, such as fish predation, may have played a leading role in community shaping. The distinct differences between pond communities, four years after the revitalisation works, resulted more from different habitat features than from the previous sediment removal.

9

State of the Art in the End-of-Life Vehicle Recycling

Lenort Radim, Staš David, Wicher Pavel, Straka Martin

Rocznik Ochrona Środowiska

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2021

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Tom 23

902--913

EN

Growing ecological awareness in society and legal regulations aimed at reducing the negative impact of used products on the environment means that waste management begins to play a significant role in the modern world. Therefore, it is necessary to conduct research towards the organization and implementation of waste management. It has been noticed that an important link in the economy is the recycling of used products. Thus, numerous studies are undertaken in the direction of organization, improvement, automation and computerization of the product and material recycling process. The article presents the results of literature research in terms of the implementation of the end-of-life vehicle recycling process.

10

Investigation of the frother effect in two and three phases systems on bubble size, surface tension, recovery and grade in chalcopyrite flotation

Ceylan Adnan, Bulut Gülay

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 6

23--35

EN

In this study, the effect of frother was investigated in two and three phases in the systems of the flotation. While the two-phase system consisted of liquid and gas, the three-phase systems contained a chalcopyrite ore. The study of three-phase systems was performed with the ore on a laboratory and plant scale. Effect of the amount and type of the frothers, their mixtures, and pH were examined depending on the bubble size, grade of the concentrate, and the recovery of chalcopyrite flotation. The results showed that as the amount of frothers increased, there was a reduction in the bubble size in all experiments. Additionally, the frother mixtures gave a positive effect on the chalcopyrite flotation. One of the most important purposes of flotation frothers shrinks the air bubble. As can be understood from the tests this time reduction of the frothers bubble size has a positive effect on the flotation. Likewise, it increases the foam stable value. It is observed from this study that increasing the amount of frothers decreases the surface tension and bubble size at different pH.

11

Hydrometallurgical recovery of platinum group metals from spent automotive converters

Rzelewska-Piekut Martyna, Paukszta Dominik, Regel-Rosocka Magdalena

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 2

83--94

EN

This work presents studies on the recovery of platinum group metals (PGM), especially platinum and rhodium, from spent automotive converters using hydrometallurgical techniques such as leaching and liquid-liquid extraction. The XRD analysis confirmed the presence of indialite – the high temperature hexagonal form of cordierite (the main catalyst building material) in the solid samples. The influence of time and temperature on the leaching of PGM from spent automotive converters was investigated. The largest amounts of Pt(IV) and Rh(III) were leached with freshly prepared aqua regia and a mixture of HCl, HSO₄, and H₂O₂. Further, liquid-liquid extraction with quaternary phosphonium ionic liquid (Cyphos IL 101) was applied to recover PGM from the leach solutions (after leaching with a mixture of HCl, H₂SO₄, and H₂O₂) and to separate Pt(IV) from Rh(III).

12

Exploitation of spent nickel-metal hydride (Ni-MH) batteries as a source of value-added products

Farghal Fatma E., Abdel-Khalek Mohamed A.

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 6

95--101

EN

Spent Nickel–metal hydride batteries can be sources of valuable metals such as nickel, cobalt, manganese, rare earths and toxic chemicals. The recycling of these materials is necessary from both economic and environmental points of view. In this study the nickel is leached in acid solution followed by precipitation and thermal decomposition or by cementation. The affecting parameters such as acid type and concentration, time, temperature and solid/liquid ratio were investigated. The maximum of leached nickel could be obtained in 3M sulfuric acid at 65°C for 60 min with solid-to-liquid ratio of 30 g L-1. The liquid film is a more suitable model for demonstrating the kinetics of the nickel leaching. Thermal decomposition of the precipitated nickel dimethyl-glyoxime was employed in preparation of nickel oxide. Nickel was separated from aqueous solution by cementation on zinc. The cementation process follows pseudo first-order kinetics and diffusion controlling steps. The yield was 91% of the original nickel content.

13

Analytical Approach for Simulating the Compression and Recovery Behaviour of Nonwoven Fabrics for Automotive Floor-Covering Application under Static Loading

Azami A. A., Payvandy P., Jalili M. M.

Fibres & Textiles in Eastern Europe

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2021

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Nr 4 (148)

62--68

EN

In this study, viscoelastic model parameters are obtained to predict the compression and recovery behaviour of needle-punched nonwoven textiles which are customarily used in industrial applications such as automotive floor-coverings. To this end, two different models are used to explain the compression and recovery behaviour of non-woven textiles under brief, moderate static loading (BMSL) and prolonged, heavy static loading (PHSL) according to ISO 3415 and ISO 3416, respectively. The first model consists of a linear spring and damper set parallel to each other. This combination is placed in series with a linear damper. The second model, however, consists of a linear spring and damper set parallel to each other and placed in series with a nonlinear damper. The results obtained for the compression and recovery behaviour of the non-woven textiles under BMSL and PHSL are compared with experimental results. The results obtained indicated that the nonlinear model is more accurate in the prediction of the compression and recovery behaviour of needle-punched nonwoven textiles under static loading than the linear model. The best result for the prediction of the compression and the recovery behaviour of nonwoven textiles under BMSL and PHSL occurs with the nonlinear model, in which the errors are 4.68% and 4.66%, respectively, when compared to the experimental results.

PL

W pracy podjęto próbę przewidywania zachowania przy ściskaniu i regeneracji igłowanych włóknin używanych w zastosowaniach przemysłowych, takich jak wykładziny podłogowe w samochodach. W tym celu zastosowano dwa różne modele, tak aby wyjaśnić zachowanie włókniny przy ściskaniu i regeneracji przy krótkim, umiarkowanym obciążeniu statycznym (BMSL) i długotrwałym, dużym obciążeniu statycznym (PHSL), odpowiednio, zgodnie z ISO 3415 i ISO 3416. Pierwszy model składał się z liniowej sprężyny i amortyzatora ustawionych równolegle do siebie. Ta kombinacja była umieszczona szeregowo z amortyzatorem liniowym. Drugi model składał się ze sprężyny liniowej i amortyzatora ustawionych równolegle do siebie i połączonych szeregowo z amortyzatorem nieliniowym. Wyniki uzyskane dla zachowania się przy ściskaniu i regeneracji włókniny pod BMSL i PHSL porównano z wynikami eksperymentalnymi. Uzyskane wyniki wskazały, że model nieliniowy jest dokładniejszy w przewidywaniu zachowania przy ściskaniu i regeneracji włóknin igłowanych pod obciążeniem statycznym niż model liniowy. Najlepszy wynik w przewidywaniu ściskania i regeneracji włókniny pod BMSL i PHSL uzyskano dla modelu nieliniowego, w którym błędy wynoszą odpowiednio 4.68% i 4.66% w porównaniu z wynikami eksperymentalnymi.

14

Fotowoltaiczne kukułcze jajo w systemie gospodarowania ZSEE

Chemperek Witold

Energia i Recykling : gospodarka obiegu zamkniętego

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2021

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nr 10

44--47

PL

Ze względu na stosunkowo dużą masę paneli fotowoltaicznych wprowadzanych na rynek część reprezentujących producentów lub importerów organizacji odzysku sprzętu elektrycznego i elektronicznego zwraca uwagę na możliwe trudności w osiągnięciu wyznaczonego przepisami prawa poziomu zbierania zużytego sprzętu elektrycznego i elektronicznego (ZSEE) za rok 2021 i lata następne w grupie czwartej (sprzęt wielkogabarytowy).

15

Study on Recovery of Valuable Metals in Spent Lithium-Ion Batteries by Al2O3-SiO2-CaO-Fe2O3 Slag System

Moon Tae Boong, Han Chulwoong, Hyun Soong-Keun, Park Sung Cheol, Son Seong Ho, Lee Man Seung, Kim Yong Hwan

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 4

983--986

EN

This study investigated the recovery behavior of valuable metals (Co, Ni, Cu and Mn) in spent lithium ion-batteries based on Al2O3-SiO2-CaO-Fe2O3 slag system via DC submerged arc smelting process. The valuable metals were recovered by 93.9% at the 1250°C for 30 min on the 20 Al2O3-40SiO2-20Cao-20Fe2O3 (mass%) slag system. From the analysis of the slag by Fourier-transform infrared spectroscopy, it was considered that Fe2O2 and Al2O3 acted as basic oxides to depolymerize SiO4 and AlO4 under the addition of critical 20 mass% Fe2O3 in 20 Al2O3-40SiO2-Cao-Fe2O3 (Cao + Fe2O3 = 40 mass%). in addition, it was observed that the addition of Fe2O3 ranging between 20 and 30 mass% lowers the melting point of the slag system.

16

The use of alternative fuels in the cement industry as part of circular economy

Uliasz-Bocheńczyk Alicja, Deja Jan, Mokrzycki Eugeniusz

Archives of Environmental Protection

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2021

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Vol. 47, no. 4

109--117

EN

The alternative waste fuels have a significant share in the fuel mix of the cement industry in Poland. The conditions inside cement kilns are favorable enough for environmentally-friendly use of waste fuels. In the article, the authors discuss the current situation concerning the use of alternative fuels in Poland, from difficult beginning in the 1990s to the present time, different kinds of fuels, and the amounts of used fuels. The use of fuels in Poland is presented against the global and EU consumption (including Central European countries and companies). The increased use of waste-derived fuels, from the level of about 1% at the end of the 1990s to the present level of about 70%, allowed for the limitation of waste storage, including avoidance of greenhouse gas emissions and consumption of conventional energy sources; those effects also contributed to the implementation of the sustainable development and circular economy conceptions. The experiences of the cement plants worldwide prove that the use of waste fuels is ecological and economical. The examples showed in the article confirm that cement plants are greatly interested in using waste fuels from waste, as they invest in the infrastructure allowing to store bigger amounts of waste and dose them more efficiently. Thus, the cement industry has become an important element of the country’s energy economy and waste management system.

17

New approach for calculation of recycling rates of municipal waste in the circular economy (CE)

Dorosz Aneta, Generowicz Agnieszka, Kultys Henryk

Architecture Civil Engineering Environment

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2021

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Vol. 14, no. 4

125--136

EN

In December 2020, new waste recycling targets were adopted for the functioning of municipal waste management systems, which are the result of the transformation of the Polish waste management system from a linear model into circular economy. Municipal waste management systems are very diverse, undergoing a constant evolution since 2013, i.e. since municipalities took over the management of the system, related to the collection, processing and disposal of waste, they must be effective, i.e. achieve the objectives of environmental policy. The assumptions of the European Union (EU) environmental policy, in particular new waste recycling rates set until 2035, determine the direction of development of waste management and at the same time the implementation of circular economy. The aim of the paper is to analyse the methods of calculating new recycling rates permitted by European law and to try to implement the methodology into national regulations. In addition, based on the available statistical data on the Polish municipal waste management system, the analysis was supplemented by simulation of solution enabling the achievement of high recycling levels in 2035.

18

Management of post-production wood waste in the aspect of circular economy

Komorowicz Magdalena, Janiszewska Dominika, Wróblewska Hanna, Stuper-Szablewska Kinga

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2021

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No. 115

72--76

EN

Management of post-production wood waste in the aspect of circular economy. Sustainable resource management involves turning waste into resources. The estimation of various waste streams and their potential use as secondary raw materials underlies the circular economy. The management of wood waste in terms of the Circular Economy should assume material use of this waste before energy use. One of the possibilities of material management of this waste is the use of biological treatment through composting. Input materials for the composting process should have technological and physical-chemical characteristics, respectively. The aim of this study was to characterize the wood raw material (wood waste as a by-product) and qualify it for the composting process on the basis of its composition. Based on the literature research, it was found that there is possibility of using these wastes for management through biological disposal. The obtained composts from wood waste can be used as a raw material to supply the soil with humic substances and mineral compounds.

PL

Potrzeba zagospodarowania poprodukcyjnych odpadów drzewnych w świetle założeń gospodarki cyrkularnej. Zrównoważony sposób gospodarowania zasobami zakłada przekształcanie odpadów w zasoby. Oszacowanie strumieni różnorodnych odpadów i potencjalnych możliwości ich zastosowania jako surowców wtórnych leży u podstaw gospodarki o obiegu zamkniętym (GOZ). Zagospodarowanie odpadów drzewnych w ujęciu Gospodarki Cyrkularnej powinno zakładać wykorzystanie materiałowe tych odpadów przed wykorzystaniem energetycznym. Jedną z możliwości zagospodarowania materiałowego tych odpadów jest zastosowanie biologicznej utylizacji poprzez kompostowanie. Zastosowanie odpadów drzewnych jako materiałów wejściowych do procesu kompostowania powinna poprzedzić odpowiednia charakterystyka technologiczna i fizyko-chemiczna. Dojrzałe komposty z odpadów drzewnych powinny znaleźć przyrodnicze zastosowanie do zasilania gleby w substancje humusowe i związki mineralne.

19

Odzysk srebra z pyłów polerskich przy zastosowaniu wybranych topników

Bałaban Wiktoria, Zgrzędek Patrycja, Matuła Tomasz

Rudy i Metale Nieżelazne Recykling

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2020

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R. 65, nr 11-12

28--29

PL

Srebro pozyskiwane jest z rud oraz odzyskiwane w procesach recyklingu. Duża zawartość cennego metalu znajduje się w odpadach po obróbce wytworzonych produktów ze srebra. W pracy przedstawiono metodę odzysku srebra z pyłów polerskich poprzez ich przetopienie. Dodanie odpowiedniego topnika gwarantuje większy uzysk srebra podczas procesu. Do badań zastosowano w celu porównania azotan sodu, krzemionkę oraz boraks.

EN

Silver is obtained from ores and recovered in recycling processes. A high content of precious metal is found in the waste from the treatment of silver products. The paper presents a method of silver recovery from polishing dusts by melting them. Adding the appropriate flux guarantees greater silver yield during the process. Sodium nitrate, silica and borax were used for comparison.

20

Odzyskiwanie soli fosforanowych(V) z rzeczywistych ścieków z przemysłu mineralnych nawozów fosforowych : kinetyka procesu

Hutnik Nina, Stanclik Anna

Przemysł Chemiczny

|

2020

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T. 99, nr 5

761--766

PL

Wyznaczono parametry kinetyczne ciągłej krystalizacji strąceniowej struwitu z rzeczywistych ścieków z przemysłu mineralnych nawozów fosforowych (IWW). Wyniki badań i obliczeń porównano z danymi kinetycznymi struwitu otrzymanego z rzeczywistej gnojowicy bydlęcej (CLM) i z wodnego roztworu jonów fosforanowych(V) bez zanieczyszczeń (WI). Do obliczeń przyjęto model kinetyki dla idealnego krystalizatora MSMPR (mixed suspen-sion, mixed product removal) zakładający zależność szybkości wzrostu kryształów od ich rozmiarów RE SDG (Rojkowski exponential, size-dependent growth). Stwierdzono, że zanieczyszczenia w ściekach spowodowały wydzielenie produktów stałych o wyraźnie różnej jakości. Średni rozmiar kryształów struwitu zmieniał się od 36,8 µm (IWW) do 48,5 µm (WI). Jednorodność ich populacji, oceniona współczynnikiem zmienności CV, zmieniała się w granicach od zadowalającej (CV 64,6%, WI) do niekorzystnej (CV 98,8%, CLM). Szybkość zarodkowania struwitu zwiększyła się od 6,27·10¹¹ 1/(s·m³) (WI) do 2,01·10¹⁵ 1/(s·m³) (IWW). W ściekach tych zanotowano odpowiednio największą (6,92·10⁻⁹ m/s) i najmniejszą (4,58·10⁻⁹ m/s) wartość liniowej szybkości wzrostu kryształów struwitu.

EN

Kinetic parameters describing continuous reaction crystallization of struvite from real P mineral fertilizers industry wastewaters (IWW) were detd. Test results were compared with kinetic data of struvite manufactured from real cattle liq. manure (CLM) and from a soln. without any impurities (WI). Kinetic model for ideal mixed suspension, mixed product removal (MSMPR) crystallizer was used assuming dependence of crystal growth rate on its size (Rojkowski exponential size-dependent growth). The impurities present in the wastewaters were a reason for pptn. of solid product of distantly different quality. The mean size of struvite crystals varied from 36.8 µm (IWW) to 48.5 µm (WI). Homogeneity within their populations, quantified by the coeff. of variation CV, varied from satisfactory (CV 64.6%, WI) to unfavorable (CV 98.8%, CLM) values. A rise of impurities concn. in a feed resulted in an increase of nucleation rate from 6.27·10¹¹ 1/(s·m³) (WI) to 2.01·10¹⁵ 1/(s·m³) (IWW). Linear growth rate of struvite crystals varied from 6.92·10⁻⁹ m/s to 4.58·10⁻⁹ m/s, resp.