Thermogravimetric (TG) studies of the reaction of lead oxide with lead sulphide

In the paper, results of thermogravimetric study on reaction between lead oxide and lead sulphide, both loose and agglomerated samples. The research results showed that the reaction of lead sulphide with lead oxide is possible at temperatures exceeding 850 oC. Comparing the influence of the reaction temperature on the course of the TG curve and the percentage weight loss of the samples, it was found that the percentage weight loss of the samples increased with the increase of the temperature. This effect was observed both for samples introduced in loose form, as well as for the agglomerated one

Wettability in the liquid Cu-Ag alloy – fireproof material – gas phase system

In the present paper, results of wettability studies on the liquid metal – fireproof material – gas phase system using copper and Cu-Ag alloys as well as typical fireproof materials, i.e. aluminium oxide, magnesium oxide and graphite, are presented. Contact angle measurements were conducted at 1 373–1 573 K by means of a high-temperature microscope coupled with a camera and a computer equipped with a program for recording and analysing images. For the measurements, the sessile drop method was used

Reduction of copper slag with the use of carbon granulates

The investigation results on the reduction of slag from flash smelting furnace and the use of carbon granulates obtained from fine-grained waste materials of both the coal enrichment and coking processes have been presented in the paper. The investigation results on the reduction of slag from flash furnace and the use of carbon granulates obtained from fine-grained waste materials of both the coal enrichment and coking processes have been presented in the paper

Crystallization of struvite from synthetic wastewater in experimental installation under flow conditions

Crystallization of struvite from synthetic wastewater in experimental installation under flow conditions. In this review paper are presented the issue of struvite insewage treatment plants and the results of struvite crystallization conditions, depending on the flow velocity and pH. Our results show a high complexity of the issues concerning the formation of struvite in pipes and confi rm the fact that the crystallizing of struvite decreases in diameter pipelines. It was also found that with increasing speed and pH increases the amount of produced struvite.W pracy przedstawiono problem związany ze spontaniczną krystalizacją uwodnionego fosforanu amonowo-magnezowego (struwitu), o wzorze chemicznym MgNH4 PO4·6H2O często tworzącego się w linii osadowej oczyszczalni ścieków. Anonsowane badania realizowane były przy wykorzystaniu instalacji doświadczalnej do krystalizacji struwitu w skali laboratoryjnej w warunkach przepływowych. Struwitu wytrącany w rurociągu uzyskiwany został z roztworu sporządzonego na bazie następujących związków: NH4Cl (źródło NH 4+), MgSO4(źródło Mg2+) i KH2 PO4(źródło PO43-). Parametrami zmiennymi była prędkość przepływu ścieków oraz odczyn. Celem nadrzędnym charakteryzowanych badań jest określenie warunków minimalizacji ilości struwitu

Crystallization of struvite in change conditions pH index and concentrations analysed components

W pracy przedstawiono problem związany z krystalizacją uwodnionego fosforanu amonowo-magnezowego (struwitu), o wzorze chemicznym MgNH4PO4 ∙6H2O często tworzącego się w linii osadowej oczyszczalni ścieków. Badania krystalizacji struwitu wykonane zostały w skali laboratoryjnej przy założeniu trzech zmiennych niezależnych jakimi były odczyn pH, stężenie jonów fosforanowych PO43- i stężenie jonów amonowych NH4+. Wielkością poszukiwaną było wymagane stężenie jonów magnezu Mg2+, przy których następuje wytrącanie się struwitu. Stwierdzono, że krystalizacja struwitu występuje w szerokim zakresie stężenia jonów fosforanowych i amonowych, lecz najsilniej zależy od odczynu. W analizowanych warunkach struwit nie wytrącał się przy pH równym 7,0 natomiast od 7,5 wytrącał się w coraz większym zakresie stężeń poszczególnych składników.The paper presents the problem of crystallization of hydrated magnesium ammonium phosphate (struvite), a chemical formula MgNH4PO4 · 6H2O often formed in the line of wastewater treatment plant sludge. Struvite crystallization tests were performed on a laboratory scale, assuming three independent variables which were pH, concentration of phosphate ions PO4 3- and the concentration of ammonium ion NH4 +. The size of a search was required concentration ofmagnesium ions Mg2+, which occurs when struvite precipitation. It was found that the crystallization of struvite occurs in a wide range of concentrations of phosphate and ammonium ions, but most depend on the reaction. In the analyzed conditions, struvite is not precipitated at pH 7.0 from 7.5 and precipitated an increasing range of concentrations of individual components

Reduction of Lead Oxide by Fine-Grained Carbonaceous Materials

As part of the presented work, tests were carried out to check the possibility of replacing of conventional reducers used in the lead pyrometallurgical processes by cheaper, but equally effective substitutes. For research of lead oxide reduction, the following fine-grained carbonaceous materials were used, ie anthracite dust and coal flotation concentrate, as well as traditional used coke breeze for comparison. The obtained test results indicate a similar ability to reduce the lead oxide of all studied carbonaceous materials