Evaluation of soda ash production parameters from Beypazarı trona ore


Tezin Türü: Doktora

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Maden Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2003

Öğrenci: SİBEL ÖRGÜL

Danışman: MUSTAFA ÜMİT ATALAY

Özet:

This study was carried out with Beypazari trona ore having a grade about 85 % trona (Na2CO3.NaHCO3.2H2O). The main target of the study is the determination of calcinations and leaching parameters, which are the two main unit operations in the production of soda ash (Na2CO3) from trona ore. Calcination parameters; calcination duration, calcination temperature and particle size were determined by using three different heat treatment systems, namely laboratory type muffle furnace, up draught furnace and microwave oven. As an alternative, wet type microwave-induced calcination which completes the decomposition of trona in solution was also investigated. Thirty minutes of calcination time was sufficient for complete calcination of ا6.35 mm trona sample at 175 °C with the muffle furnace. Calcination of trona with microwave treatment was completed in a shorter time. The nature of thermal reactions and structural changes of trona during calcination were elucidated by TG (Thermogravimetry), DTG (Derivative Thermogravimetry), SEM (Scanning Electron Microscope) and XRD (X-ray diffraction) analysis. The effect of heat treatment on grindability, specific surface area and decrepitation of trona were also investigated. In the last stage of the study, leaching parameters; leaching time, leaching temperature and pulp density were determined for both uncalcined and calcined samples. 80 % leach recovery was obtained in 4 minutes for ا6.35 mm particle size of uncalcined sample in 25 % pulp density while 100 % leach recovery was reached for the calcined samples under the same conditions.