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1

Enhancing filtration rate of new valley oxidized phosphate concentrate with additives

Abdel-Aal E.-S., Abdel Rahman E., Kandil A.-H.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 1

124--135

EN

Phosphoric acid is utilized for production of fertilizers. It is mainly produced by wet processes, in which phosphate concentrate, produce by several operations including crushing, scrubbing, classification, attritioning, and desliming, is leached with sulfuric acid with coproduction of calcium sulfate dihydrate (phosphogypsum). The New Valley oxidized phosphate concentrate was processed for phosphoric acid production by addition of certain additives to improve gypsum filtration through modifying its morphology and particle size distribution. The additives used were cetylpyridinium chloride (CPC) as a cationic surfactant, sodium dodecyl sulfate (SDS) as an anionic surfactant and sulfonic acid (SA). The applied dosages ranged from 0.25 to 2.5 kg additive/Mg P2O5 in the phosphate concentrate. The filtration rate of the New Valley oxidized phosphate concentrate is 3.6 Mg P2O5 /m2day without additives. The filtration rate was increased by 33% and 31% with 1 and 0.8 kg/Mg P2O5 doses of CPC surfactant and sulfonic acid (SA), respectively. On the other hand, the filtration rate was decreased by 33% with addition of 1 kg/Mg P2O5 dose of SDS. The aspect ratios of gypsum crystals were 6:1, 3:1, 3:1 and 12:1 without additive, with CPC, SA and SDS surfactant, respectively. Reaction efficiencies without and with 0.8 kg/Mg P2O5 of CPC, SA and SDS dose of additives were 95.0%, 97.9%, 97.9% and 94.7%, respectively. The P2O5 recoveries without and with 0.8 kg/Mg P2O5 of CPC, SA and SDS dose of additives were 92.6%, 95.5%, 95.8% and 90.8%, respectively.

2

Reaction crystallization of struvite in a continuous DTM type crystallizer with a compressed air driven jet pump

Matynia A., Mazieńczuk A., Piotrowski K., Wierzbowska B., Hutnik N., Kozik A.

Polish Journal of Chemical Technology

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2011

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Vol. 13, nr 2

46-53

EN

Experimental tests covering the production of struvite MgNH4PO4ź6H2O from water solutions containing 1.0 mass % of phosphate(V) ions using magnesium and ammonium ions in stoichiometric proportions were carried out in a crystallizer of 1.2 dm3 working volume. The process temperature was 298 K. Struvite crystals of mean size Lm from ca. 14 to ca. 38 µm were produced depending on the process environment's pH (9-11) and the mean residence time of suspension in a crystallizer, τ (900-3600 s). In such defined process conditions the linear growth rate of struvite crystals changed from 1.45ź10-8 m/s (pH 9, τ 900 s) to 2.06ź10-9 m/s (pH 11, τ 3600 s) while the nucleation rate from 5.1ź10^7 to 3.2ź10^9 1/(sm3). Crystal product of the most advantageous granular characteristics was produced at pH 9 and the mean residence time 3600 s. Within this product population the largest sizes reached above 200 µm while the number of crystals smaller than 3 mm was kept below 6%.

3

Odzyskiwanie jonów fosforanowych(V) z roztworów odpadowych zawierających zanieczyszczenia organiczne

Kozik A., Hutnik N., Matynia A., Gluzińska J., Piotrowski K.

Chemik

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2011

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Vol. 65, nr 7

675-686

PL

Wydzielano w sposób ciągły struwit z wodnego roztworu zawierającego jony fosforanowe (0,20% mas.), magnezu i amonu w proporcjach stechiometrycznych i kwas mlekowy (0,03 lub 0,06% mas.). Proces prowadzono w temperaturze 298K w krystalizatorze typu DT MSMPR z wewnętrzną cyrkulacją zawiesiny. Przebadano wpływ pH (od 8,5 do 10) i średniego czasu przebywania zawiesiny w krystalizatorze (od 900 do 3600 s) na rozkład rozmiarów kryształów produktu, ich jednorodność i kształt, oraz na kinetykę zarodkowania i wzrostu kryształów struwitu. W badanym zakresie parametrów procesowych otrzymano kryształy produktu o średnim rozmiarze od 28,6 do 80,0 mm o zróżnicowanym pokroju i jednorodności. Ich liniowa szybkość wzrostu wynosiła od 7,68?10-9 do 2,29?10-8 m/s. Najlepiej wykształcone kryształy, o typowym dla struwitu kształcie i pożądanej jednorodności otrzymano w zakresie pH 8,5 x9 i wydłużonym średnim czasie przebywania 3600 s. W tak zdefiniowanych warunkach kwas mlekowy, symulujący obecność substancji organicznych w rozcieńczonym wodnym roztworze fosforanów(V), ogólnie korzystnie oddziaływał na przebieg i rezultaty badanego procesu.

EN

Struvite was continuously produced from water solutions containing phosphate(V) ions (0.20 mass %), magnesium and ammonium ions in stoichiometric proportions, as well as lactic acid (0.03 or 0.06 mass %). Reaction crystallization of struvite was carried out in temperature 298 K in DT MSMPR type crystallizer with internal circulation of suspension. Influence of pH (from 8.5 to 10) and mean residence time of suspension in the crystallizer (from 900 to 3600 s) on product crystal size distributions, crystal phase homogeneity and shape, as well as on struvite nucleation and crystal phase growth kinetics was identified. Within the process parameter ranges tested product crystals of mean size from 28.6 to 80.0 mm, of diversified habit and size homogeneity were reported. Their linear growth rate varied from 7.68x10-9 to 2.29x10-8 m/s. The best crystals, of typical for struvite shape and required homogeneity were produced at pH 8.5 - 9 and for elongated mean residence time 3600 s. In such defined process conditions lactic acid, simulating presence of organic substance load in diluted water solution of phosphates(V), influenced course and final results of the investigated process advantageously.

4

Próby oszacowania szybkości wzrostu kryształów witaminy C

Wierzbowska B., Koralewska J., Matynia A., Piotrowski K.

Inżynieria i Aparatura Chemiczna

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2006

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Nr 4s

152-153

EN

The research results concerning a linear growth rate of vitamin C crystals in the L(+)-ascorbic acid - methanol-ethanol - water system are presented. This kinetic parameter of batch crystallization process was calculated on the basis of crystal product population density distribution. The distributions were determined using two different methods, viz. the particle size laser analyzer and conventional mesh analysis.

5

Modelowanie składu ziarnowego struwitu otrzymywanego w procesie ciągłej krystalizacji strąceniowej za pomocą sztucznych sieci neuronowych

Piotrowski K., Koralewska J., Matynia A., Wierzbowska B.

Inżynieria i Aparatura Chemiczna

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2006

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Nr 5s

114-115

EN

The potential application of artificial neural networks for the kinetic analysis of complex struvite reaction-crystallization processes in a DTM continuous crystallizer with inner circulation of suspension forced by a liquid-liquid jet-pump was presented, verified and discussed.

6

Krystalizacja masowa KHCO3 w procesie karbonizacji katolitu z elektrolizy wodnego roztworu chlorku potasu

Lemanowska E., Buczkowski R., Igliński B

Inżynieria i Aparatura Chemiczna

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2004

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Nr 4-5

31-33

PL

W pracy przedstawiono opis krystalizacji masowej wodorowęglanu potasu w procesie karbonizacji katolitu z elektrolizy wodnego roztworu chlorku potasu w oparciu o analizę rozkładu rozmiarów kryształów. Sporządzono histogramy unormowanego rozkładu liczbowego kryształów KHCO33 zawiesiny). Zaproponowano metodę produkcji potażu z roztworów po elektrolizie chlorku potasu.

EN

This work describes mass crystallization of potassium bicarbonate in the carbonization process of catholyte from the electrolysis of potassium chloride solution on the basis of crystal size distribution analysis. Histograms of the normalized numbers distribution of KHCO3 crystals have been prepared and the relationship Mi o = f (t) (where: Mi o - number of crystals in 1m3 suspension) has been presented. The method of potash production from solution after electrolysis of potassium chloride has been proposed.

7

The investigation of the process obtaining potassium carbonate

Buczkowski R., Lemanowska E., Kasikowski T.

Polish Journal of Applied Chemistry

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2003

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Vol. 47, nr 4

295-306

EN

Potassium carbonate is one of the most important inorganic compounds used in industry. Now, it is mainly obtained by the chemisorption of carbon dioxide into an aqueous solution of potassium hydroxide which was produced in the process of electrolysis of potassium chloride brine. In this paper, the results of the studies of absorption of carbon dioxide in potassium lye coming from the membrane electrolysis of potassium chloride are presented. The aim of our research was to determine basic parameters of the following processes: a) isothermal chemisorption of carbon dioxide into an initially concentrated potassium hydroxide solution at temperatures: 313 K, 333 K, and 353 K, b) polythermal crystallization of the carbonate-potassium salts within the range of 373-293 K, and c) filtration of the reaction suspension, and calcination of the product.

PL

Węglan potasu jest jednym z najważniejszych nieorganicznych składników wykorzystywanych w przemyśle. Obecnie, wytwarzany jest głównie w wyniku absorpcji dwutlenku węgla w wodnym roztworze wodorotlenku potasu otrzymanym w procesie elektrolizy roztworu chlorku potasu. W pracy przedstawiono wyniki badań absorpcji dwutlenku węgla w ługu potasowym z elektrolizy membranowej KCl. Celem badań było wyznaczenie podstawowych parametrów procesowych: a) izotermicznej chemisorpcji dwutlenku węgla we wstępnie zatężonym roztworze KOH w temperaturze: 313, 333, i 353 K oraz b) politermicznej krystalizacji soli węglanowo- potasowych w zakresie 373-239 K filtracji zawiesiny poreakcyjnej oraz operacji kalcynacji produktu.

8

The quality of barium sulphate crystals obtained during continuous precipitation crystallization in the process of post quenching salts utilization

Matynia A.

Polish Journal of Chemical Technology

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2002

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Vol. 4, nr 4

19-25

EN

The research results of barium ions precipitation process by means of crystalline ammonium sulphate (VI) addition are presented. The influence of feeding solution composition: barium, sodium, potassium and calcium chlorides concentration, the temperature and also the residence time on the product quality are discussed. The experiments were conducted continuously in the crystallizer with internal circulation of the suspension; the computer controlled the course of experiments. Crystal size distribution of the product was obtained by means of COULTER counter test. The possibility of the process description with the principles of MSMPR crystallizer model was analyzed. The research results may be utilized in the technology of post quenching salts processing.