Studies on Solar Drying of Oily Sludge

2012 ◽  
Vol 443-444 ◽  
pp. 54-59
Author(s):  
Lei Lei Mi ◽  
Nai Rui Liu ◽  
Ming Meng
Keyword(s):  
Water Content ◽  
Large Scale ◽  
Experimental Result ◽  
Oily Sludge ◽  
Solar Drying ◽  
Industrial Sludge ◽  
Solar Dryer ◽  
Drying Treatment ◽  
Sludge Drying ◽  
Dried Sludge

The overall objective of this study was to provide some references for large-scale drying treatment of particular industrial sludge such as oily sludge. Considering the features of oily sludge as well as the characteristics of solar drying, solar dryer was designed and established in order to conduct the sludge drying treatment under sealed and low-temperature condition. The major parts of solar dryer were air collector and drying chamber. Drying treatment of oily sludge after conditioning and dewatering was performed with the designed solar dryer. The main measurements were temperatures of major components of solar dryer and water content of sludge. The experimental result indicates that the water content of oily sludge can be decreased by a maximum of 18% in use of the designed solar dryer. It is also proposed that the emitted volatile hydrocarbon and alcohols be recycled and the dried sludge be incinerated.

scholarly journals Laboratory Simulation of Solar Dryer for Tropical Woods: The Case of Ebony (Diospyros Crassiflora)

2014 ◽  
Vol 09 (1) ◽  
Keyword(s):  
Water Content ◽  
Laboratory Simulation ◽  
Initial Water Content ◽  
Solar Drying ◽  
Initial Water ◽  
Modest Contribution ◽  
Solar Dryer ◽  
Tropical Woods ◽  
The Town ◽  
Local Materials

In the present paper, a numerical modeling of solar dryer is doing. This solar dryer operates in the natural convection condition and his construction is not difficult because, local materials are used and it is not necessary to follow a particular formation. We have obtained a numerical solution which explains experimental solution. Application is doing on ebony wood that is a wood most difficult to dry and most utilized for the sculpture. With 30mm of thickness, the sample passed 25 days to reduce his water content to 15%, initial water content was equal to 27%, and the drying period is the month of March from the town of Yaoundé, political capital of Cameroon. This modeling proposed is a modest contribution to explain the solar drying of tropical woods at the laboratory scale

scholarly journals Spatial variation and mechanisms of leaf water content in grassland plants at the biome scale: evidence from three comparative transects

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ruomeng Wang ◽  
Nianpeng He ◽  
Shenggong Li ◽  
Li Xu ◽  
Mingxu Li
Keyword(s):  
Spatial Variation ◽  
Water Content ◽  
Large Scale ◽  
Life Forms ◽  
Important Variable ◽  
Leaf Water ◽  
Leaf Water Content ◽  
Desert Grassland ◽  
Large Spatial Scale ◽  
Grassland Plants

AbstractLeaf water content (LWC) has important physiological and ecological significance for plant growth. However, it is still unclear how LWC varies over large spatial scale and with plant adaptation strategies. Here, we measured the LWC of 1365 grassland plants, along three comparative precipitation transects from meadow to desert on the Mongolia Plateau (MP), Loess Plateau, and Tibetan Plateau, respectively, to explore its spatial variation and the underlying mechanisms that determine this variation. The LWC data were normally distributed with an average value of 0.66 g g−1. LWC was not significantly different among the three plateaus, but it differed significantly among different plant life forms. Spatially, LWC in the three plateaus all decreased and then increased from meadow to desert grassland along a precipitation gradient. Unexpectedly, climate and genetic evolution only explained a small proportion of the spatial variation of LWC in all plateaus, and LWC was only weakly correlated with precipitation in the water-limited MP. Overall, the lasso variation in LWC with precipitation in all plateaus represented an underlying trade-off between structural investment and water income in plants, for better survival in various environments. In brief, plants should invest less to thrive in a humid environment (meadow), increase more investment to keep a relatively stable LWC in a drying environment, and have high investment to hold higher LWC in a dry environment (desert). Combined, these results indicate that LWC should be an important variable in future studies of large-scale trait variations.

scholarly journals Effects of Blanching and Natural Convection Solar Drying on Quality Characteristics of Red Pepper (Capsicum annuum L.)

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
James Owusu-Kwarteng ◽  
Francis K. K. Kori ◽  
Fortune Akabanda
Keyword(s):  
Natural Convection ◽  
Quality Characteristics ◽  
Red Pepper ◽  
Plain Water ◽  
Drying Methods ◽  
Solar Drying ◽  
Drying Time ◽  
Sun Drying ◽  
Overall Acceptability ◽  
Solar Dryer

The objective of this work was to determine the effects of blanching and two drying methods, open-sun drying and natural convection solar drying, on the quality characteristics of red pepper. A 2 × 3 factorial design with experimental factors as 2 drying methods (open-sun drying and use of solar dryer) and 3 levels of pepper blanching (unblanched, blanched in plain water, and blanched in 2% NaCl) was conducted. Dried pepper samples were analysed for chemical composition, microbial load, and consumer sensory acceptability. Blanching of pepper in 2% NaCl solution followed by drying in a natural convection solar dryer reduced drying time by 15 hours. Similarly, a combination of blanching and drying in the solar dryer improved microbial quality of dried pepper. However, blanching and drying processes resulted in reduction in nutrients such as vitamin C and minerals content of pepper. Blanching followed by drying in natural convection solar dryer had the highest consumer acceptability scores for colour and overall acceptability, while texture and aroma were not significantly (p>0.05) affected by the different treatments. Therefore, natural convection solar dryer can be used to dry pepper with acceptable microbial and sensory qualities, as an alternative to open-sun drying.

Analytical solution for soil water redistribution during evaporation process

2013 ◽  
Vol 68 (12) ◽  
pp. 2545-2551 ◽  
Author(s):  
Jidong Teng ◽  
Noriyuki Yasufuku ◽  
Qiang Liu ◽  
Shiyu Liu
Keyword(s):  
Analytical Solution ◽  
Water Content ◽  
Soil Water ◽  
Exponential Function ◽  
Experimental Result ◽  
Water Evaporation ◽  
Evaporation Process ◽  
Climate Control ◽  
Water Redistribution ◽  
Control Apparatus

Simulating the dynamics of soil water content and modeling soil water evaporation are critical for many environmental and agricultural strategies. The present study aims to develop an analytical solution to simulate soil water redistribution during the evaporation process. This analytical solution was derived utilizing an exponential function to describe the relation of hydraulic conductivity and water content on pressure head. The solution was obtained based on the initial condition of saturation and an exponential function to model the change of surface water content. Also, the evaporation experiments were conducted under a climate control apparatus to validate the theoretical development. Comparisons between the proposed analytical solution and experimental result are presented from the aspects of soil water redistribution, evaporative rate and cumulative evaporation. Their good agreement indicates that this analytical solution provides a reliable way to investigate the interaction of evaporation and soil water profile.

scholarly journals Drying kinetics of ‘babassu’ mesocarp

2017 ◽  
Vol 21 (10) ◽  
pp. 709-714 ◽  
Author(s):  
Jhonatas C. Rosa ◽  
Andreza P. Mendonça ◽  
Angélica dos S. Oliveira ◽  
Sylviane B. Ribeiro ◽  
Andréia do R. Batista ◽  
...  
Keyword(s):  
Experimental Data ◽  
Water Content ◽  
Animal Feed ◽  
Coefficient Of Determination ◽  
Residual Distribution ◽  
Solar Dryer ◽  
Error Standard Deviation ◽  
Forced Air ◽  
Final Water Content ◽  
Best Fit

ABSTRACT ‘Babassu’ mesocarp flour has been used by the pharmaceutical, human food and animal feed industries. However, there is lack of standardization in the production, as well as absence of information on the management of the product’s quality. Thus, the objective of this study was to dry the ‘babassu’ mesocarp in forced-air oven and solar dryer, adjust different mathematical models to the experimental data, as well as to quantify the levels of proteins and crude fiber of the produced flour. The criteria for the adjustment were the coefficient of determination, magnitude of the mean relative error, standard deviation of estimate and the residual distribution trend. Drying in the shortest time occurred in oven at 60 °C (370 min), leading to water content of 4.62%, while in the solar dryer the final water content was 8.07% in 6 days. The mathematical model Two Terms showed the best fit to the experimental data for oven drying and the Midilli model showed the best fit in solar dryer. There was an increase in protein content with the drying in solar dryer and oven at 40, 50 and 60 °C (1.36, 1.33, 1.15 and 1.37%, respectively) in relation to fresh mesocarp (0.88%). Drying in both oven and solar dryer promoted increase of protein in the flour.

scholarly journals Solar Drying Technology in Indonesia: an Overview

2018 ◽  
Vol 9 (4) ◽  
pp. 1804 ◽  
Author(s):  
Ahmad Fudholi ◽  
Abrar Ridwan ◽  
Rado Yendra ◽  
Ari Pani Desvina ◽  
Hartono Hartono ◽  
...  
Keyword(s):  
Solar Energy ◽  
Large Scale ◽  
Clean Energy ◽  
Solar Drying ◽  
Energy Technology ◽  
Important Benefit ◽  
Pollutant Source ◽  
Drying Technology

<span lang="EN-US">The most important benefit of solar energy is renewable and low pollutant source of energy (clean energy). Solar energy technology and research are developing fast and much of the technology needed for these applications in industry and agricultures is already available. Solar drying technology (SDT) is one of the most attractive and promising applications of solar energy technology. In this paper, the various performances of SDTs in Indonesia are summarized with details. Generally, the cabinet-type and tunnel-type SDTs are remarkably well suited to drying small quantities of vegetables and fruit on the household scale. Greenhouse and hybrid SDTs are suitable for use on a large scale by industries.</span>

scholarly journals Comparative study of different drying methods regard to the phenols and flavonoids content of dried Citrus aurantium L. leaves

2021 ◽  
Author(s):  
Geovanni Hernandez Galvez ◽  
Margarita Castillo Téllez ◽  
Jorge de Jesús Chan González ◽  
Francisca Méndez Morales ◽  
Damianys Almenares López ◽  
...  
Keyword(s):  
Natural Convection ◽  
Forced Convection ◽  
Design Methodology ◽  
Total Phenol ◽  
Drying Methods ◽  
Total Flavonoids ◽  
Citrus Aurantium ◽  
Solar Drying ◽  
Solar Dryer ◽  
Total Flavonoids Content

Objective: To determine the effects of different thermal drying technologies on the total phenol and flavonoid contents (TPC) and total flavonoids (TFC) in sour orange (Citrus aurantium L.) leaves. Design/methodology/approach: Solar drying was carried out in outdoor sunny conditions using two direct solar dryers; one with natural convection, the other with forced convection. The total phenol and flavonoid contents in gallic acid equivalents (GAE) and quercetin (Q), respectively, of ethanolic extracts of C. aurantium were assessed with spectrophotometric techniques. Results: The results demonstrated maximum phenol values for the direct natural convection solar dryer (161.4 mg EAG/g MS) and minimum values for shade drying (61.43 mg EAG/g MS). As for flavonoids, the highest values were obtained in the direct forced convection solar dryer (32.22 ± 1.6 mg EQ/g MS), while the lowest was registered in the open air sun (11.72 mg EQ/g MS). Conclusions: Direct solar dryers are technologies effective for maintaining the phenols and total flavonoids content in dried leaves of C. aurantium.  

scholarly journals Relative water content consistently predicts drought mortality risk in seedling populations with different morphology, physiology, and times to death

2020 ◽  
Author(s):  
Gerard Sapes ◽  
Anna Sala
Keyword(s):  
Water Content ◽  
Real Time ◽  
Pinus Ponderosa ◽  
Mortality Risk ◽  
Relative Water Content ◽  
Large Scale ◽  
Water Status ◽  
Physiological Indicators ◽  
Relative Water ◽  
Global Impacts

AbstractPredicted increases in forest drought mortality highlight the need for predictors of incipient drought-induced mortality (DIM) risk that enable proactive large-scale management. Such predictors should be consistent across plants with varying morphology and physiology. Because of their integrative nature, indicators of water status are promising candidates for real time monitoring of DIM, particularly if they standardize morphological differences among plants. We assessed the extent to which differences in morphology and physiology between Pinus ponderosa populations influence time to mortality and the predictive power of key indicators of DIM risk. Time to incipient mortality differed between populations but occurred at the same relative water content (RWC) and water potential (WP). RWC and WP were more accurate predictors of drought mortality risk than other physiological indicators, including non-structural carbohydrate (NSC) content and percent loss of conductivity (PLC). These results highlight that variables related to water status capture critical thresholds during DIM and the associated dehydration processes. Both WP and RWC are promising candidates for large-scale assessments of DIM risk. RWC is of special interest because it allows comparisons across different morphologies and can be remotely sensed. Our results offer promise for real time landscape-level monitoring of DIM and its global impacts.

Numerical Analysis on Thermal Energy Storage Device With Finned Copper Tube for an Indirect Type Solar Drying System

2018 ◽  
Vol 140 (3) ◽  
Author(s):  
Satyapal Yadav ◽  
V. P. Chandramohan
Keyword(s):  
Energy Storage ◽  
Numerical Analysis ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Air Flow ◽  
Storage Device ◽  
Energy Storage Device ◽  
Solar Drying ◽  
Solar Dryer ◽  
Air Flow Velocity

Solar dryer with thermal energy storage device is an essential topic for food drying applications in industries. In this work, a two-dimensional (2D) numerical model is developed for the application of solar drying of agricultural products in an indirect type solar dryer. The phase-change material (PCM) used in this work is paraffin wax. The study has been performed on a single set of concentric tube which consists of a finned inner copper tube for air flow and an outer plastic tube for PCM material. The practical domain is modeled using ANSYS, and computer simulations were performed using ANSYS fluent 2015. The air velocity and temperature chosen for this study are based on the observation of indirect type solar dryer experimental setup. From this numerical analysis, the temperature distribution, melting, and solidification fraction of PCM are estimated at different air flow velocities, time, and inlet temperature of air. It is concluded that the drying operation can be performed up to 10.00 p.m. as the PCM transfers heat to inlet air up to 10.00 p.m. and before it got charged up to 3.00 p.m. because of solar radiation. The maximum outlet temperature is 341.62 K (68.62 °C) which is suitable for food drying applications. Higher air flow velocity enhances quick melting of PCM during charging time and quick cooling during recharging of inlet air; therefore, higher air flow velocity is not preferred for food drying during cooling of PCM.

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