جستجوی مقالات مرتبط با کلیدواژه "کاهش رطوبت" در نشریات گروه "مهندسی شیمی، نفت و پلیمر"

One of the ore dressing steps in Gol Gohar Mining and Industrial Company is dewatering from slurry containing 60 weight percent of the iron concentrate. At present, this dewatering step is carrying out by a continuous strip filter, which is a kind of vacuum filter. At the present research the role of ionic and non-ionic surface activators in reducing the moisture, content of the iron ore particles, after filtration, has been investigated. Surface activators used were sodium dodecyl sulfate (SDS), polyethylene glycol 4000 (PEG4000), sodium dodecyl ether sulfate (SLES) and acetyl tri methyl ammonium bromide (CTAB). In this work amount of 30, 45, 60, 75 and 90 g/ton of the mentioned surfactants were added to the slurry. To evaluate effect of each surfactant, in addition to amount of filter cake humidity, other experiments including filtration kinetics, Zeta potential, contact angle measurement, and FTIR analysis on the samples were carried out. The results showed that SDS and SLES anionic surface activators have a significant effect on the reducing cake moisture. The best results obtained at 75 g /ton of the surfactants and the average moisture reduction in filter cake obtained about 2%. On the other hand, polyethylene glycol 4000 had a negligible effect, 0.5%, on the final cake humidity. The results from addition of acetyl tri methyl ammonium bromide (CTAB) showed that using this chemical reagent does not help to the slurry dehumidification.

Osmotic dehydration of fig fruits (cv. Sabz) in ternary solution of water, sucrose and sodium chloride at different solution concentrations, temperature and process durations were analyzed. A comparative approach was made between artificial neural network (ANN) and response surface methodology (RSM) to predict the mass transfer parameters. Results showed that all independent variables positively decreased the weight meaning that increasing each factor resulted in increasing weight loss and this relationship was linear. Osmo-dehydrated figs had better quality compared to samples without osmosis. All four independent variables explained 94% of the weight loss, 90% moisture content reduction and 89% of the solid gain. The determined optimum processing conditions were temperature of 60°C, sucrose concentration of 70%, sodium chloride concentration of 5% and immersion time of 5h. The results showed that properly trained ANN model is found to be more accurate in prediction as compared to RSM model.