Higher Equilibrium Moisture Content Research Articles

Using industrial waste in porous building materials for indoor humidity control

This study uses waste bricks and waste catalyst as raw materials in the synthesis of humidity control building materials with high structural strength. This paper explores the feasibility of producing porous humidity control materials (PHCM) through the billet sintering of waste brick with various quantities of waste catalyst (0 %–40 %) for indoor construction. N2 adsorption and desorption isotherms revealed that PHCM exhibits Type-IV adsorption with H3 hysteresis loops, indicating a network of interconnected mesopores with diameters ranging from 3 to 17 nm. Humidity control analysis revealed that increasing the waste catalyst content significantly enhanced the equilibrium moisture content and moisture adsorption and desorption capacity. This study determined that the adsorption of moisture within the PHCM relies on capillary condensation within the mesopores. Under 95 % relative humidity (RH), the highest equilibrium moisture content (2.97 kg/kg) and 12-h moisture adsorption capacity (72.41 g/m2) were obtained in specimens prepared at a sintering temperature of 1000 °C with a 40 % spent catalyst. This excellent adsorption capacity can be attributed to the high surface area of the waste catalyst, which increased the surface area of PHCM from 0.013 to 8.529 m2/g. This study demonstrates the benefits of synthesizing PHCM using waste bricks and catalysts in terms of porous properties, mechanical properties, and humidity control performance.

Effect of hygrothermal aging on compression behavior of CFRP material with different layups

This study investigates the mechanical degradation mechanism and statistical analysis of residual compressive strength of three lay-up laminates under more than one-year seawater environment. Fick and Langmuir model were used to describe the moisture absorption process with a maximum moisture equilibrium content of 3.78% and various characterization methods were used to reveal the microstructural evolution of CFRP during aging. Experimental results demonstrate that the multiple fiber directions in the MD specimens provide additional moisture absorption channels, leading to a stronger wicking effect and a higher equilibrium moisture content. The layups can significantly affect the compression failure mode after long-term aging. The compressive strength of the cross-ply and multidirectional laminates decreased by 50% while that of unidirectional laminates decreased by 28%, and surface cracking is easily observed in the aged specimens. An empirical prediction model based on the Langmuir model and experimental data was proposed and verified by the data from the literature, with at least a 10% improvement in prediction accuracy. Meanwhile the three-parameter Weibull distribution was used to describe the residual compressive strength after hygrothermal aging and tested by Kolmogorov-Smirnov test. It is expected to provide insight for the application of CFRP in seawater environment.

Functionalization of mesoporous Al-MCM-41 for indoor humidity control as building humidity conditioning material

This study sought to overcome the high energy consumption of mechanical dehumidifiers by synthesizing humidity control materials using alumino-silicate raw materials extracted from stone sludge and cathode ray tube (CRT) waste panel glass. The structure of the synthesized materials matches that of Mobil Composition of Matter No. 41 (MCM-41) mesoporous molecular sieves, which was subjected to amine functionalization using (3-Aminopropyl) triethoxysilane at various concentrations (2.5, 5, 7.5 vol.%). The resulting materials were characterized using X-ray fluorescence analysis, small angle X-ray diffractometry, Fourier transform infrared spectroscopy, transmission electron microscopy, the Brunauer–Emmett–Teller method, and 27Al solid-state nuclear magnetic resonance spectrometry. Al-MCM-41 molecular sieves with 5.0% grafted amine functional groups presented high specific surface area and high pore uniformity resulting in the highest equilibrium moisture content (39.4 kg/kg). The high thermal and humidity buffer capacity of the proposed material could greatly enhance the comfort of interior spaces without the energy consumption of mechanical dehumidifiers.

Environmentally friendly protection of European beech against fire and fungal decay using a combination of thermal modification and mineralisation

ABSTRACT The demand for construction timber is continuously increasing, due to its favourable characteristics. However, the adequate protection of wood is key to its successful use, as it is flammable and susceptible to biodegradation. Given that thermal modification enhances the durability of wood, and mineralisation with CaCO3 considerably improves its fire properties, it is worth considering the combined effects of the two methods. European beech (Fagus sylvatica) was selected to determine the effects of a) thermal modification, b) mineralisation through the in-situ formation of CaCO3, and c) a combination of the two procedures, on resistance to decay fungi, reaction to fire and the mechanical properties of the wood. Microscopic analysis and comparisons of the samples before and after exposure to fungi were also conducted. Mineralised wood generally had a slightly alkaline pH value and higher equilibrium moisture content, while thermal modification lowered the equilibrium moisture content. The present study demonstrated the combined effect of thermal modification and mineralisation: the best response to fire as well as resistance to fungi was achieved when the two treatments were combined. Results from the Brinell hardness and three-point bending tests indicate that both modification procedures can slightly impair the mechanical properties of the wood.

Effect of Wood Extractives on the Equilibrium Moisture Content of Six Sudanese Hardwood Species

The objective of this investigation was to study the effect ofextractive content on the wood sorption isotherms of six Sudanese hardwoodspecies i.e. Acacia nilotica, A.senegal, Anogeissus leiocarpus, Boswelliapapyrifera, Ailanthus excelsa and Calotropis procera growing in North andSouth Kordofan States. For each species, wood samples were collected fromsix trees, from which specimens were prepared. The effect of extractives onequilibrium moisture content was studied by comparing the equilibriummoisture content of hot water extracted and unextracted wood. Experimentalequilibrium moisture content values for extracted and unextracted specimenswere obtained at different levels of relative humidity. These specimens wereplaced in a closed desiccator, which contained saturated salt solution ordifferent concentrations of sulphuric acid to maintain relative humidity andthen kept in an oven at the specified temperature (60 ○C) until equilibriummoisture content was obtained. Desorption and adsorption isotherms of thesix wood species exhibited sigmoid curves. The results showed directrelationship between equilibrium moisture content and relative humidity thatcould be well explained by third-order polynomial functions. The effect ofextraction was significant at few relative humidity values in some species;unextracted wood had higher equilibrium moisture content than extractedwood.

Size Effect on Hygroscopicity of Waterlogged Archaeological Wood by Simultaneous Dynamic Vapour Sorption

Hygroscopicity is one of the most important properties of wood and plays a decisive role in its dimensional stability. In this context, conservation plans for waterlogged archaeological wood (WAW) and relevant waterlogged artefacts must be created. The size of the sample required for a moisture sorption assessment may affect the results for (and thus the perception of) the hygroscopicity of a testing artefact. Herein, to investigate the effects of the sample size on the hygroscopicity of WAW as measured via dynamic vapour sorption (DVS), typical WAW and recent (i.e., sound) wood are processed into four differently sized samples, ranging in thickness from 200 mesh to millimetre. The equilibrium moisture contents (EMCs) of the wood samples are simultaneously measured using simultaneous DVS. The sorption isotherms show that the EMC values of the recent wood at each relative humidity increase as the sample size decreases, with the superfine powder sample achieving the highest EMC of all of the recent samples. Although the WAW has a higher EMC than that of recent wood, the effect of the size of the WAW sample on its hygroscopic properties is surprisingly not as pronounced as that for the recent wood. In addition, the hysteresis between the samples of different sizes of the archaeological wood is significantly smaller than that for the reference samples. Furthermore, regarding the standard deviations of the parameters obtained from the Guggenheim Anderson de Boer and Hailwood–Horrobin models, the values for WAW are all much smaller than those for the reference wood. This further verifies the disappearance of the size effect of the hygroscopicity for WAW.

Surface and Physical Features of Thermo-Mechanically Modified Iroko and Tauari Wood for Flooring Application

The aim of the study was to determine the selected surface and physical properties of iroko (Milicia excelsa (Welw.) C.C. Berg) and tauari (Couratari spp.) wood after thermo-mechanical treatment (TMT) in relation to extractive content. During TMT, no chemicals are introduced into the wood, which distinguishes this method from a number of wood modification methods. The iroko and tauari wood were subjected to volumetric densification in a hydraulic press. The wood was densified in a radial direction at a temperature of 100 and 150 °C. The wood color parameters were measured using the mathematical CIE L*a*b* and L*C*h color space models. The roughness parameters of Ra and Rz parallel and perpendicular to the grain were investigated. The contact angle (CA) of the wood with distilled water was determined based on the sessile drop method. The equilibrium moisture content (EMC) and dimensional changes of the wood were determined for a climate with a temperature of 20 °C and a relative humidity (RH) of 9%, 34%, 55%, 75% and 98%. The tauari wood was less prone to color changes under the influence of TMT than the iroko wood. After densification, the iroko and tauari wood displayed a different character of roughness changes. The iroko wood featured the lowest level of roughness after TMT at 100 °C, and the tauari wood after TMT at 150 °C. The densified iroko and tauari wood were characterized by weaker dynamics in the changes in their respective contact angles than the non-densified wood. The higher the temperature of the TMT, the lower the EMC of the wood. Higher EMC values were observed for the tauari wood than for the iroko wood. This was due to the lower content of chloroform-ethanol extractives. Similar dependencies were obtained in the case of hot water extractives. The thermo-mechanically treated wood displayed a greater tendency towards dimensional changes in a climate with high relative air humidity, i.e., above 70%, compared to the non-modified wood.

INFLUENCE OF ELECTROMAGNETIC FIELD OF EXTREMELY LOW FREQUENCIES ON HYGROSCOPIC PROPERTIES OF WHEAT GRAIN MASS

The research results of the influence of electromagnetic field (EMF) of extremely low frequencies (ELF) on hygroscopic properties of Shestopalivka wheat variety of 2019 harvest have been given. Grain processing was performed on the experimental stand that consisted of the polymeric cylindrical container for grain, solenoid coil, generator of electromagnetic waves GZ-112/1 and a power amplifier of low frequency. The output signal of generator was set in the form of sine wave and controlled by oscillograph C1-78. The studies were performed at EMF frequencies of 10, 16, 24 and 30 Hz. Magnetic induction of grain treatment was constant and equaled 10 mTl. The duration of grain processing was 6 minutes.The equilibrium moisture content of wheat grain was determined by the tensometric method at temperatures t 9 °C and 23 °C and relative humidity φ 33…36 % and 82…82.5 %. The necessary conditions of air were created in desiccators with solutions of sulfuric acid placed in thermostats and refrigerators.It has been determined that the equilibrium moisture of wheat grain processed by EMFof ELF – is in the range of 12.17…20.56 %, and unprocessed grain – in the range of 12.62…21.03 %. Regardless of the frequency of EMF, equilibrium moisture content of the grain wheat processed by EMF varies according to the known laws – decreases with temperature increase and increases with increasing of air relative humidity. It has been shown that the impact of processing by EMF of ELF on the equilibrium moisture contentof wheat grain is manifested at different frequencies in different ways, which is likely due to the resonance phenomena. It has been established that the processing of grain by EMF with frequencies of 10...30 Hz practically has no effect on the equilibrium moisture content of grain at 23 °C and a relative humidity of 33...82.5 % which remains practically at the level of the unprocessed grain. It has been shown that the processing of grain by EMF with frequencies of 24 and 30 Hz under conditions of t = 9 °C and φ = 33 % leads to higher equilibrium moisture content compared to unprocessed wheat grain from 14.45 % to 16.85...16.95 %. Processing of grain with frequencies of 10 and 16 Hz under the same conditions, on the contrary – leads to a decrease in the level of equilibrium moisture content to 13.74…13.86 %. Empirical coefficients have been determined and the equation has been proposed that describes the dependence of equilibrium moisture content of not processed and processed wheat grain by EMF with frequency 10...30 Hz on temperature and relative humidity of the ambient air.

Sorption behavior and isosteric heat of maize-millet based protein enriched extruded product

Moisture sorption behaviour and isosteric heat of sorption are essential to be familiar with the stability of products, various storage condition and selection of packaging materials. Sorption behavior of extruded product was done at 30, 40, 50 and 60 °C temperatures under 11–92% relative humidity. The product was developed from an optimized blend of maize, defatted soy, finger millet and yam at an optimum condition of 14% (wb) feed moisture, 110 °C barrel temperature and 301 rpm screw speed. The net isosteric heat of sorption of the extruded product was determined by using Clausius-Clapeyron equation. The equilibrium moisture content (EMC) was found to be raised with the rise in water activity (aw) in particular temperature. The highest EMC 30.05% (db) was recorded at 0.92 aw and 30 °C temperature, whereas the lowest EMC 2.46% (db) at 0.11 aw and 60 °C temperature. The isotherms exhibits curves of Type-II for four temperature conditions. The EMC data were fitted to six sorption models and GAB model was found to be best fitted among them. The net isosteric heat of sorption varied between 16.711 and 3.242 kJ/mol within 5–30% (db) of sample moisture content.

Molecular sieve material from liquid–crystal-display waste glass and silicon carbide sludge via hydrothermal process with alkali fusion pretreatment

The goal of this paper was to synthesize eco-humidity-conditioned Al-MCM-41 mesoporous molecular sieves (CHCMs) from liquid–crystal-display waste glass (LCDWG) and silicon carbide sludge (SiCS) via an alkali fusion process. LCDWG and SiCS are primarily composed of SiO2 and Al2O3. The characterization of CHCM materials under different synthesis conditions and their humidity regulation effects were compared. The results showed that the CHCM materials exhibit type-IV isotherms and clearly defined capillary phenomena and were composed of hexagonal Al-MCM-41, which is a mesoporous material. When the optimal reaction temperature was 120 °C, and the liquid/solid ratio (L/S) was 15, the highest equilibrium moisture content of the synthesized CHCM sample was 66.84 m3/m3. In addition, the large surface area (1120 m2/g), pore size (5.2 nm), pore volume (0.93 cm3/g) and wall thickness (1.44 nm) of the samples improved the moisture absorption capacity of the equilibrium moisture content. The equilibrium moisture content of the CHCM samples was higher than those of rape straw concrete and hemp concrete (9.8–17.8 m3/m3) and that of a diatomite/ground calcium carbonate composite material (11.7 m3/m3). This study focused on the unique properties of synthesized CHCM samples and the utilization of LCDWG and SiCS to produce samples and thereby solve the disposal problem associated with LCDWG and SiCS. Therefore, CHCMs can be used in several applications, particularly as CHCM materials in construction.

Drying of oak wood lamellas: Part 1. Analysis of the process in a dehumidification kiln

The subject of this paper is to analyse the drying process of oak lamellas, which are the solid wood top layer of engineered wood flooring. The focus of the first part of the paper is on dehumidification kilns. Drying in a dehumidification kiln is an interesting alternative to conventional drying of thin solid oak wood with the aim of reaching high drying quality in a reasonable time. Drying tests were done in an industrial dehumidification kiln, and drying parameters were compared with the drying in the conventional kiln. Simultaneously, a drying test at a higher temperature was done in the programmable climate chamber. It was demonstrated that thin oak lamellas (approx. 5 mm thick) could be successfully dried in a dehumidification kiln in a relatively short time and with high drying quality. With the applied drying schedule (initial temperature of 36?C, final temperature of 46?C), the drying cycle will last 2 to 5 days, depending on the amount of wood and the initial MC. Due to the high rate of water evaporation and the inability of the kilns to remove it fast enough, the drying of lamellas in both dehumidification and conventional kilns takes place at a higher equilibrium moisture content than the set values.

Effect of air velocity, temperature, and relative humidity on drying kinetics of rubberwood

Kiln drying of rubberwood lumbers is a complex transport phenomenon for realistic modeling and simulation. To decouple this complexity, researchers usually divide their research into two parts. The first one is single-lumber drying kinetics to describe how wood lumber responds to its surface conditions. Then they combine this drying kinetics with a lumped transport model or dispersion model or computational fluid dynamics. The mathematical models are then solved numerically to predict the industrial kiln drying behaviors. This work focuses on the drying kinetics of stacked rubberwood lumbers using hot air at different air velocity (0.5, 1.5, 2.5, 3.5, 4.0 m/s), relative humidity (6–67% relative humidity (RH)) and temperature (60–100 °C). The drying kinetics followed the conventional drying theory. However, the two drying periods, namely constant and falling rate (CRP and FRP), were not distinct. As the air velocity increased, the transition from CRP to FRP is faster. The middle of the transition period (at critical moisture content, CMC) moves closer to the fiber saturation point (FSP). The overall mass transfer coefficients in the falling rate period for stacked rubberwood drying were lower than those predicted by the Ananias correlation. Hence, a modified formula was proposed, representing the overall moisture transfer coefficients as a function of air velocity, temperature, relative humidity, and lumbers thickness for the range of variables under investigation satisfactorily. In general, the drying rate and the overall moisture transfer coefficient increased with increasing air velocity, drying temperature, and decreasing RH. Relative humidity directly affects the driving force of moisture transfer rate because higher RH is associated with higher equilibrium moisture content. A lumped parameter model for kiln drying was also developed. After being integrated with the estimated mass transfer coefficient, the model can predict the moisture profiles in lab-scale kiln drying satisfactory, although the model needs more validation data. These kinetic parameters and correlation for stacked rubberwood drying can be used in more complex models and process optimization in future research.

Determination of Equilibrium Moisture Content in Trade Distribution

Maize is one of essential crop in Indonesia. Maize trade distribution showed economic condition in society. If the distribution trade was poor, the quality and quantity of product will be low, consequences to uncontrolled condition in society. Every actor in distribution trade play important role. Farmer for instance, if the farmer produces low quality of maize grain, will resulted unacceptable product in factory. The acceptance of maize in feed factory is determined by several factor, such as moisture content, microorganism contamination, and presence of pest. To know the best recommendation treatment to prevent rejected product in feed factory, it is important to de-termine the moisture content in trade distribution, because the higher mois-ture content would increases the possibility of microorganism contamina-tion. Besides, the best condition storage is also critical for keeping the quali-ty of maize grain. Therefore, determination of equilibrium moisture content (EMC) will help the policies maker to consider environment condition for their storage. In this study, the maize EMC was determined using Hender-son’s equation. The results showed that the highest EMC was found in the maize after threshing (23.49±0.58%). The postharvest treatment, such as drying and sortation is very important apply in such point

Drying characteristics of non-centrifugal sugar

Non-centrifugal sugar (NCS), generally known in most parts of Asia as jaggery, is a commonly used sweetener in food preparations. Sun drying of NCS has been reported to improve its shelf life. However, there is no systematic study, supported by relevant data and analysis, for this claim. In this article, the influence of temperature and relative humidity (RH) of the medium on the drying rate of jaggery is studied. The optimum drying temperature and humidity for jaggery of different compositions are determined. Jaggery containing low levels of reducing sugars (RSs) (2–5%) has lower equilibrium moisture content (EMC). For this reason, moisture could be reduced to as low as 0.5% within 250 minutes. Case-hardening is realized for the product with low RS content (typically ≤ 6%), and it does not allow one to employ high temperatures for drying. For jaggery containing high RS (10–15%), case-hardening was not evident, while the higher EMC does not permit moisture reduction below 4–5% under otherwise similar conditions.

Production of briquettes using coconut and eucalyptus wastes

ABSTRACT This research analyzed the production and characteristics of briquettes composed of residues of Cocos nucifera and Eucalyptus pellita wood. A completely randomized design was used, having seven treatments and five repetitions per treatment. The treatments corresponded to waste percentages of coconut and eucalyptus residues as following: T1: 100% eucalyptus waste; T2: 20% coconut waste + 80% of eucalyptus waste; T3: 40% coconut waste + 60% of eucalyptus waste; T4: 50% coconut waste + 50% of eucalyptus waste; T5: 60% coconut waste + 40% of eucalyptus waste; T6: 80% coconut waste + 20% of eucalyptus waste; and, T7: 100% coconut waste. For the production of briquettes, 0.5% carboxymethylcellulose (CMC) was used as the binder. The mixtures were compacted under a load of 568 kgf cm-² for three minutes. After pressing, the briquettes were air-dried to the equilibrium moisture of the environment and, then, analyzed for physical, chemical and energy characteristics. The data were analyzed through analysis of variance, correlations and hierarchical cluster analysis (HCA). The briquettes produced with 100% of C. nucifera residues had the highest equilibrium moisture content, high volatile matter concentrations, and low fixed carbon concentrations. The basic density, the apparent specific mass and the burning rate were not affected by the composition and by the equilibrium moisture of the briquettes.

Effect of High-pressure Densification on Moisture Sorption Properties of Paulownia Wood

The effect of high-pressure (HP) densification (30, 90, and 150 MPa for 3, 30, and 300 s) on the moisture sorption properties of Paulownia wood was investigated. After the densification, samples were conditioned at three temperatures (20, 30, and 40 °C) and five equilibrium moisture contents (from 11.20 to 95.62%) during the study, after which the equilibrium moisture contents of the control and treated samples were measured. The HP-treated groups had higher equilibrium moisture contents than the controls at higher relative humidity levels. The hysteresis phenomenon and the scanning electron microscopy observations were explained by the transformation of the structural elements by the HP treatment. Finally, two moisture sorption isotherm (MSI) models (a linear polynomial model for adsorption and a quadratic polynomial model for desorption) were established with good performance to describe the relationship between HP treatment parameters, environmental conditions, and equilibrium moisture contents.

Changes in Physical Properties of Sugi, Hinoki, and Korean Pine Wood after Fire-retardant Treatment

The effect of a fire-retardant treatment on some physical properties, including dimensional stability, hygroscopicity, and surface color variation of Sugi (Cryptomeria japonica), Korean Pine (Pinus koraiensis), and Hinoki (Chamaecyparis obtusa) were investigated in this study. These softwoods were subjected to vacuum-pressure and impregnated with a developed fire-retardant chemical. The results showed that the radial and tangential swelling of 1% moisture content (MC) increment were lower for all three wood species compared with the control specimen after the fire-retardant treatment, despite higher equilibrium moisture content (EMC) at 75% relative humidity (RH) and 90% RH at 40 °C. Meanwhile, the bulk coefficient after water immersion decreased for all specimens after the treatment, which indicated higher dimensional stability. However, the fire-retardant treatment proved a shift in surface color to darkness.

Performance comparison of different plant fiber/soybean protein adhesive composites

To compare the properties of different plant fiber/soybean protein adhesive composites, six types of plant fibers (rice straw, wheat straw, peanut straw, rice husk, wheat husk, and peanut shell) were selected as reinforced materials, and soybean protein adhesive was used as the adhesive. Six types of different bio-composites were prepared by the compression molding process. The Fourier transform infrared (FTIR) spectra, mechanical properties, moisture absorption, and thermal stability of the composites were measured. The tensile cross-section microstructure of the composites was examined. Results showed that the peanut straw/soybean protein adhesive composite contained more hydrophilic groups. The wheat fiber-based composites possessed more hydrogen bonds, leading to the best binding interface compatibility and mechanical properties. The wheat straw/soybean protein adhesive composite had the highest tensile strength, flexural strength, and impact strength, which were 337.7%, 638.6%, and 483.4%, compared to those of the rice husk/soybean protein adhesive composite, respectively. The peanut shell/soybean protein adhesive composite’s equilibrium moisture content was the lowest (8.70%). The rice husk/soybean protein adhesive composite had the highest equilibrium moisture content (14.23%), and the best thermal stability as the initial temperature of pyrolysis was 283.4 °C and the residual mass was 34.45%.

Sazonalidade da umidade de equilíbrio da madeira para o Estado de Mato Grosso

Por ser um material orgânico, heterogêneo e higroscópico, a madeira pode apresentar variações dimensionais e deformações decorrentes da interação com o ambiente. Em uso ou nos processos de secagem, quando são atingidos os equilíbrios entre a madeira e o ar atmosférico, têm-se a obtenção da umidade de equilíbrio da madeira (UEM). Em função da elevada importância dessa matéria-prima para o Estado de Mato Grosso, torna-se fundamental conhecer a sazonalidade de UEM. O presente trabalho objetivou estimar a UEM da madeira, pelo modelo de Simpson, para 30 municípios do Estado de Mato Grosso, distribuídos nas diferentes regiões de planejamento do Zoneamento Sócio-Econômico Ecológico do Estado. Os dados meteorológicos foram obtidos da Rede de Estações Meteorológicas Automáticas do Instituto Nacional de Meteorologia, entre 2006 e 2012. A UEM foi estimada diariamente, com posterior obtenção das médias mensais. Na estação seca ocorreram variações da UEM entre 5,08 e 9,57% e no período chuvoso entre 8,58 e 13,49%. Nos meses de janeiro, fevereiro e março ocorrem os maiores valores de UEM no estado. As condições ambientais durante o período seco (julho a setembro) favorecem a secagem natural da madeira serrada, por condicionarem uma secagem mais rápida.

Water Sorption Isotherm of Pea Starch Edible Films and Prediction Models.

The moisture sorption isotherm of pea starch films prepared with various glycerol contents as plasticizer was investigated at different storage relative humidities (11%–96% RH) and at 5 ± 1, 15 ± 1, 25 ± 1 and 40 ± 1 °C by using gravimetric method. The results showed that the equilibrium moisture content of all films increased substantially above aw = 0.6. Films plasticized with glycerol, under all temperatures and RH conditions (11%–96%), adsorbed more moisture resulting in higher equilibrium moisture contents. Reduction of the temperature enhanced the equilibrium moisture content and monolayer water of the films. The obtained experimental data were fitted to different models including two-parameter equations (Oswin, Henderson, Brunauer–Emmitt–Teller (BET), Flory–Huggins, and Iglesias–Chirife), three-parameter equations Guggenhiem–Anderson–deBoer (GAB), Ferro–Fontan, and Lewicki) and a four-parameter equation (Peleg). The three-parameter Lewicki model was found to be the best-fitted model for representing the experimental data within the studied temperatures and whole range of relative humidities (11%–98%). Addition of glycerol increased the net isosteric heat of moisture sorption of pea starch film. The results provide important information with estimating of stability and functional characteristics of the films in various environments.