Non-isothermal drying kinetics of human feces

Abstract

The non-isothermal drying behavior and kinetics of human feces (HF) were investigated by means of thermogravimetric analysis to provide data for designing a drying unit operation. The effect of heating rate and blending with woody biomass were also evaluated on drying pattern and kinetics. At low heating rate (1 K/min), there is effective transport of moisture, but a higher heating rate would be necessary at low moisture levels to reduce drying time. Blending with wood biomass improves drying characteristics of HF. The results presented in this study are relevant for designing non-sewered sanitary systems with in-situ thermal treatment.

Effect of Low-Frequency High-Power Ultrasound Processing on the Volatile Compounds and Aroma Profile of Cashew Apple Juice

“…Sonication took place in a jacketed beaker filled with 100 mL of cashew apple juice, and the temperature was maintained by a continuous flow of water through the jacket. These operating conditions were selected based on previous experience with ultrasound technology applied to fruit juices. − The control group was untreated cashew apple juice; all experiments were conducted thrice. The effective ultrasound power density was measured using the calorimetric method …”

Convective drying kinetics of faecal sludge from VIP latrines

“…Information about drying kinetics is lacking for faecal sludge from on-site sanitation. A few studies about human faeces and faecal sludge drying kinetics have been reported in literature [ 16 , 17 , 18 ] but none of these works have modelled their kinetic data. A few models have been developed for sewage sludge drying [ 19 , 20 , 21 ], which could serve as reference for the development of drying models specific to faecal sludge but cannot be directly transposed as the characteristics from sewage and faecal sludge differ in many aspects.…”

Solar Thermal Dewatering in Faecal Sludge Management

“…Here, the migration of water to the surface is typically achieved by capillary action and by progressive evaporation-condensation processes that are accompanied by a temperature gradient within the material. The multiple falling rates with no intermittent constant rate characterises the drying of faecal sludge as a partially wet, partially dry process (78).…”

“…Due to the level of variety between the samples it suggests that the process which removes the moisture within the samples from the interior to the surface could occur via a different phenomenon. This is due to the level of compactness within the sample impacting the moisture transport and diffusion process within the material, leading to an impedance in the migration of water from the inside to the surface of the sample (78). The graphs show that when drying ABR sludge at 155 o C it produces the largest heat flow peak, while there is then a large drop before the 105 and 205 o C peaks can be seen.…”