ABSTRACT
Aim of this study is to explore the alternate of costly desiccants such as silica gel, zeolite, etc., in the dehumidification process of evaporative cooling and food storage. Therefore, the new cow dung-based novel desiccant (CDND) material has been developed which is very cost effective and readily available organic material. This CDND has been tested experimentally to explore the suitability to replace commercially available desiccants. The experiments were carried out in two stages. First, 100 g of CDND was tested, and the adsorption and desorption characteristics were evaluated. In second stage, 2500 g of CDND in Special Design Pipe (CDNDSDP) is tested to study adsorption and regeneration and how long it takes to attain adsorption equilibrium without regeneration under different inlet air conditions. In the present study, it is found that this novel desiccant is regenerated in only 28 mins and ready for dehumidification processes for next 120 mins, which demonstrates continuous regeneration of CDND is not required. In addition, the regeneration of CDND is found to be 54ºC that is quite significant and can be attained easily using low-grade energy. Further, CDND is organic material and reutilization will help in terms of solid waste management.
Abbreviation
AC | = | Adiabatically Cooled |
ANN | = | Artificial Neural Network |
CDND | = | Cow dung based novel desiccant |
CLED | = | Cost effective liquid desiccant |
CD | = | Chemical desiccant |
CaCl2 | = | Calcium chloride |
CDNDSDP | = | Cow dung-based novel desiccant special design pipe |
CSE | = | Conventional source of energy |
CFCs | = | Chlorofluorocarbons |
DBCDS | = | Desiccant-based cooling and dehumidification system |
DPT | = | Dew point temperature |
DAC | = | Desiccant air conditioning |
ECS | = | Evaporative cooling system |
IAQ | = | Indoor air quality |
LD | = | Liquid desiccant |
LiCl | = | Lithium chloride |
LiBr | = | Lithium bromide |
LDS | = | Liquid desiccant system |
LDAC | = | Liquid desiccant air conditioning |
NCSE | = | Non-conventional source of energy |
RAC | = | Refrigeration and air conditioning |
SD | = | Solid desiccant |
SDC | = | Solid Desiccant Cooling |
SDD | = | Solid desiccant dehumidification |
VCRS | = | Vapor compression refrigeration System |
Nomenclature
P | = | Applied Pressure(kPa) |
Ck | = | Chemical potential |
= | Dry bulb temperature | |
= | Decrease in moisture (kg/kg dry air) | |
= | Decreage in latent heat load (kJ) | |
S | = | Entropy (kJ/kg*K) |
= | Enthlapy of air in (kJ/kg) | |
= | Enthlapy moist in (kJ/kg) | |
= | Sensible heat load of moist air (kJ/kg) | |
L | = | Latent heat of vaporization (kJ/kg) |
= | Mass flow rate of moist air (kg/s) | |
= | Mass flow rate of DRY air (kg/s) | |
nk | = | Number of moles |
= | Surface Tension of water (N/m) | |
= | Specific heat of moist air (kJ/kg K) | |
Ps | = | Spreading Pressure (kPa) |
Ef | = | Surface free energy (kJ) |
A | = | Surface Area (m2) |
RH | = | Relative humidity |
= | Specific humidity (kg/kg dry air) | |
= | Total pressure (kPa) | |
∆T | = | Temperature increases of air (oC) |
T | = | Temperature (oC) |
V | = | Volume (m3) |
= | Vapor pressure (kPa) | |
= | Vapor at wet bulb temp (oC) | |
= | Vapor pressure at saturation (kPa) | |
= | Wet bulb temperature (oC) |
Disclosure statement
No potential conflict of interest was reported by the author(s).