Wyniki wyszukiwania - BazTech

1

Exploration and characterization of barite mineral from Azara-Nassarawa ore deposits from suitabiity in industrial applications

Nzeh Nnaemeka Stanislaus, Popoola Patricia Abimbola

Physicochemical Problems of Mineral Processing

|

2023

|

Vol. 59, iss. 2

art. no. 166104

EN

Primary concentrations of Azara barite deposit in Nassarawa state, Nigeria were conducted; employing simplified gravity concentration techniques. Particle size distribution, specific gravity, physicochemical and morphological analyses of the sample was conducted. These analyses were done in order to establish process efficacy and effectiveness of gravity concentration processes for recovery of barium from the ore deposit, as well as its suitability in various industrial applications, such as the oil and gas sectors. Thus, microstructural, chemical composition and certain physicochemical characteristics/properties of the mineral sample of Azara-Nassarawa barite were determined. XRD, XRF, SEM and EDS analyses were utilized in determining morphology as well as quantitative and qualitative chemical analyses of the sample. Barite sample with average particle size of -355+150μm was subjected to concentration, adopting jigging and tabling gravity separation as the concentration methods. Hitherto, based on quantitative and qualitative chemical analyses conducted, the sample was composed of about 36.2% BaO and 40.5% Ba, respectively; and also possessed an average specific gravity (SG) of about 3.85. Further, the qualitative analysis of the mineral products of jiggling and tabling indicated that jigging had a concentrate recovery of 130.98% Ba with SG increase of 11.2% while tabling had 89.81% Ba recovery with 8.6% SG increase. Assay and SG results confirm gravity concentration efficiency and thus, establish the barite from Azara-Nassarawa ore deposits suitable for certain industrial applications. This will serve as a tool and a step further towards mitigating existing problems or challenges in mineral concentration and processing of such deposits for industrial purposes.

2

Study of the Variations in the Vertical and Horizontal Distribution of Heavy Sand Minerals in the Hilla River Sediments

Hameed Iman A., Rahman Haleema Abdul Jabbar Abdul, Anmar Alsaadi

Journal of Ecological Engineering

|

2023

|

Vol. 24, nr 7

318--330

EN

This study was conducted to investigate the effect of the Hilla River sediments on the heterogeneity of the distribution of heavy sand minerals for the fine and very fine sand classes as well as for the surface and subsurface layers. The results showed that the heavy sand minerals that were determined according to the specific gravity of each mineral and the specific gravity of the particles of minerals identified in the soils under study ranged between (2.5–4.5) and were divided into four groups in terms of the specific gravity. The first group included each of the minerals (Mica and Chlorite) of low specific gravity, while the second group contains (Pyroxene, Amphibole, Epidote Group). The third group includes minerals (Tourmaline and Garnet, Staurolite and Kyanite) and the two groups are classified as minerals of medium-specific gravity; in turn, the fourth group contains minerals of high specific gravity, namely (Zircon, Rutile and Opaques). As a result, the most important factors affecting the sedimentation, sorting and sedimentation processes are the conveyor’s speed, load capacity, the size of the separation particles and their specific gravity. The complete mismatch of the horizontal distribution of the minerals of one group is due to the varying ranges of the specific gravity of the minerals within the general range of specific gravity.

3

Badanie wytrzymałości betonu z przetworzonym kruszywem z recyklingu

Kasagani Hanuma, Sali Tanuja, Rao C. B. K.

Cement Wapno Beton

|

2019

|

R. 22/84, nr 3

238--247

PL

W pracy zbadano wpływ kruszywa z recyklingu, poddanego sortowaniu, czyszczeniu, ścieraniu w bębnie Devala, myciu i suszeniu na właściwości betonu. Zbadano właściwości fizyczne tego kruszywa, wpływające na właściwości mieszanki betonowej oraz betonu stwardniałego. Ustalono zależność pomiędzy ciężarem właściwym, nasiąkliwością i ilością przylegającej do kruszywa starej zaprawy dla różnych poziomów zastąpienia kruszywa naturalnego kruszywem z recyklingu, aby umożliwić skrócenie czasu potrzebnego do przeprowadzenia badań wstępnych kruszywa. Badano mieszanki betonowe o dwóch klasach wytrzymałości, w których odpowiednio 0%, 25%, 50%, 75% i 100% kruszywa naturalnego zastąpiono kruszywem z recyklingu. Kruszywo to było poddane ścieraniu w bębnie Devala przez dwie i cztery godziny. Zastosowanie kruszywa poddanego ścieraniu przez dwie godziny spowodowało poprawę wytrzymałości do maksymalnie 7% dla klasy wytrzymałości M25 i 20% dla klasy wytrzymałości M35 w porównaniu z betonem zawierającym kruszywo niepoddane ścieraniu. Zastosowanie kruszywa poddanego ścieraniu przez cztery godziny spowodowało zmniejszenie wytrzymałości betonu. Mieszaniny zawierające kruszywo poddane ścieraniu wykazywały lepszą urabialność w porównaniu do mieszanek betonowych z kruszywem z recyklingu, które nie było poddane ścieraniu.

EN

In this study the influence of processed recycled aggregate which has undergone grading, cleaning, attritioning, washing and drying on the properties of concrete was examined. The physical properties of recycled aggregate which may affect the fresh and hardened properties of concrete were also investigated. A relation has been established between the specific gravity, water absorption and the amount of adhered mortar for the natural aggregate substitutions with recycled aggregate to lessen the time required for carrying out these preliminary tests on coarse aggregate. Concrete mixes with 0%, 25%, 50%, 75% and 100% replacement and attrition period of two and four hours for two grades of concrete have been considered in the study. The two hour attrition period showed improvement in strength to a maximum of 7 % for M25 grade and 20% for M35 grade, whereas, loss of strength was observed for recycled aggregate concrete mixes containing aggregate attritioned for four hour. Mixes incorporating recycled aggregate subjected to attritioning exhibited improved workability comparing to concrete mixes with recycled aggregate not subjected to attrition.

4

The prototype project of the position to designate the screw thruster lobe specific gravity

Kończewicz W., Stępkowski M., Skowroński M., Iwanicki L.

Journal of KONES

|

2014

|

Vol. 21, No. 3

165--170

EN

During the exploitation screw thruster, lobes are being defected in many ways. Sample types of damages are as follow: the material damages caused by cavitation, corrosion, deflection. In order to facilitate and to improve the quality of repairing activities, the idea of make the position to designate screw thruster lobes specific gravity has been initiated by Rolls-Royce Poland Company and Nautica Academic Circle. Incorrect lobes balance influences on irregular work of the screw, which results in the occurrence of adverse effects such as generation of vibration or increasing probability of mechanical elements damages during the exploitation. Screw thruster lobe specific gravity designation helps in identification of areas for treatment (welding, grinding) to achieve the desired parameters. The creation of designate screw thruster lobes specific gravity position gave the possibility of using the innovative scanning in 3D, which shows very clearly the picture of the scanning item. With Scanect and Autodesk Inventor 2014 software, we can manipulate the resulting image. This makes possibility of the lobes gabarits measurement. What is more, it designates the specific gravity exact to 10%.It increases the quality of the lobe renovation and these results in an improvement the screw thruster lobe’s work efficiency.The cooperation of The Maritime University in Gdynia and Rolls-Royce Poland Company resulted in creating the prototype, which will be tested by service technics in working circumstances.

5

Wpływ wybranych czynników na cechy fizyczne bulw ziemniaka

Sobol Z.

Inżynieria Rolnicza

|

2002

|

R. 6, nr 6

101--108

PL

Przedstawiono wyniki badań dotyczące wpływu wybranych czynników agrotechnicznych integrowanej uprawy ziemniaka, cech osobniczych i okresu przechowywania na wybrane parametry bulw, tj. ciężar objętościowy, straty masy i objętości. Wartość ciężaru objętościowego zależała przede wszystkim od okresu przechowywania, a w przypadku odmiany Maryna również od formy nawożenia. Na ubytki masy w przypadku odmiany Maryna istotny wpływ miały wszystkie przyjęte czynniki, a dla frakcji 30-40 mm tylko okres przechowywania i rodzaj nawożenia. Ubytki objętości zależały istotnie od okresu przechowywania i frakcji w obrębie odmiany Maryna oraz od okresu przechowywania i odmiany dla frakcji 30-40 mm.

EN

Paper presented the study results concerning the effect of some agrotechnical factors at integrated potato cultivation, individual traits and storage duration on chosen parameters of the tubers, such the specific gravity, losses of mass and volume. The specific gravity depended mostly on storage duration and - in the case of Maryna cultivar - on applied fertilization also. The losses of mass for Maryna cultivar were significantly affected by all the considered factors, while for the tubers fraction 30-40 mm - by the storage duration and kind of applied fertilization only. The volume losses significantly depended on storage duration and tuber fraction - for Maryna cultivar, as well as the time of storage and on the cultivar for fraction 30-40 mm.