An innovative and energy efficient sludge dewatering technology has been developed. The technology, impulse drying, involves briefly contacting the sludge under pressure with a heated surface. A unique feature of impulse drying is that the majority of moisture removal occurs as lipid water. A pilotand laboratory-scale demonstration was performed on low ash primary paper mill sludge. The pilot-s...

The study is aimed at quantifying the relative contribution of key heat transfer modes in lyophilization. Measurements of vial heat transfer rates in a laboratory-scale freeze-dryer were performed using pure water, which was partially sublimed under various conditions. The separation distance between the shelf and the vial was systematically varied, and sublimation rates were determined gravime...

An experimental investigation was conducted to study the performance of a novel indirect type free convection solar dryer. The and conventional passive dryer were built. Solar irradiation temperature different locations recorded. air at drying chamber entrance, lower space, upper space temperatures besides thermal efficiency 68, 39, 49 85%, respectively, higher than one.

rotary atomizers are commonly used in spray dryers to atomize feed. one destructive effect of wheel rotation is the creation of a vacuum inside the wheel that conducts hot air from the chamber into the wheel and can lead to atomizer blockage and an explosion. the present work determined the air-pumping characteristics of a rotary atomizer with a 50 mm wheel diameter. the vacuum pressure and pow...

monitoring the effective parameters of drying crops is necessary to evaluate and determine system performance under real conditions. hence, a monitoring system was constructed to determine the performance of a vegetation forced-convection solar dryer. digital temperature sensors were set up in the air inlet and outlet of the collector and the air outlet of the drying chamber. a program was writ...

This study was carried out to evaluate the effect of pre-treatment technique (blanching) and temperature on drying characteristics red date variety. Thin layer experiments were conducted at varying temperatures 50, 60 70 °C using electrical laboratory oven cabinet dryer with a constant air velocity 1.4 m/s. Other sets samples blanched 50 for 2-, 5- 10-minutes before being dried respectively und...

Removal of sludges from Wastewater Treatment Plants (WWTP) represents a serious worldwide environmental problem for which alternatives other than their simple incineration are investigated. In this work the treatment of raw sludge from urban WWTP by means of a minimization process through spray-drying is analyzed as well as some proposals for revaluating the resulting dry product. Analysis is s...

In this research, an industrial spray dryer was used and the effects of atomizer speed on the physicochemical properties of milk powder, the textural and sensory characteristics of white cheese made from this milk powder were evaluated. For this purpose, whole milk was converted into powder by using three different speeds (10,000, 11,000, and 12,000 rpm). The results showed that by increasing a...

This paper proposes an indirect-mode forced convection solar dryer equipped with a PV/T air collector. The collector generates both heated and electrical energy, which are used to force in the dryer. Experiments were carried out on selected tomato slices for temperature humidity readings as well masses of dried samples instantaneously recorded two days. A thermal analysis was performed drying s...