Specific Heat Capacity Values Research Articles

Specific Heat Capacity Estimations for Biologically and Medicinally Important Compounds: Lidocaine Hydrochloride, Clove Oil and β-Piperine Using the DSC Technique

Aim: To study the specific heat capacity for biologically and medicinally important compounds, namely, lidocaine hydrochloride, clove oil and beta-Piperine using the DSC technique. Background: One of the main problems in the science of medicine is the application of drug molecules with limited solubility in water and in biofluids. Solubility is related to the chemical potential of the solutes involved, which imparts free energy avenues, a necessary requirement for equilibrium processes. The convincing solutions for solving this issue are the utilization of ionic liquids as a drug. Lidocaine is the most widely utilized intraoral injected dental anesthetic prior to performing painful medical procedures. Besides that, lidocaine hydrochloride is a salt, having a melting point of 76°C (349 K) and behaves as an ionic liquid after melting. Clove oil and β-piperine are very well-known naturally occurring medicinal compounds having a broad spectrum of applications. Objective: To study the thermal gravimetry analysis behaviour for lidocaine hydrochloride, clove oil and β-piperine. To compute specific heat capacity at constant pressure, as a function of temperature for the studied systems. Methods: In the present communication, the studies of Thermal Gravimetry Analysis (TGA) and Differential Scanning Calorimetry (DSC) for these compounds are described. Results: The data of heat flow have been utilized to obtain specific heat capacity (Cp) values for lidocaine hydrochloride, clove oil and β-piperine over a temperature range between 75°C (348 K) and 155°C (428 K) based upon the methodology we have developed. Conclusion: LC•HCl behaves as an ionic liquid between 76 and 230°C (349 and 503 K). Clove oil shows lower specific heat capacity values and is similar to other organic aromatic compounds while piperine exhibits comparative high specific heat capacity values indicating possibilities of intramolecular hydrogen bonding, which is generally not affected by temperature.

Fe addition influence on the mechanical and thermophysical behaviours of PM Alumix 431 alloy

We investigated Alumix 431 alloy powder mixed with Fe element with a ratio of 2.5, 5 and 10 (wt%) using powder metallurgy method (PM) and sintered at 610°C temperature for an hour under N2 gas atmosphere. The structural and morphological properties of Alumix 431-2.5, 5 and 10 Fe (wt%) mixtures determined using x-ray diffraction (XRD), optical microscope (OM), and scanning electron microscopy (SEM). XRD data showed that dominant α-Al phases mixed with increasing Fe content and resulted in a peak shift in the alloy. SEM images revealed Al/Al-rich areas and intermetallic phases such as Fe-Al, Al13Fe4, Fe2Al5, and Al7Cu2Fe mixtures as well as cracks and grain boundaries. The mechanical and thermophysical properties of the alloys studied and maximum hardness value obtained with a mixture of 10% Fe mixture as 28.46 HB. Maximum bulk density, minimum porosity, and water adsorption values of mixtures were obtained on the Alumix 431-10% Fe mixtures which are 2.50 g/cm3, 7.60%, and 3.03%, respectively. The maximum specific heat capacity and enthalpy values were found to be 1.94 J/g°C at 400°C temperature for the Alumix 431-2.5% Fe and 886.48 J/g at 595°C for Alumix 431-10% Fe mixtures. These results showed that the mixture of the Alumix 431-Fe alloy improved the mechanical and thermophysical properties due to PM method, Al-based and Al-Fe phase formations such as Al7Cu2Fe and Al2CuMg phases.

Thermal properties of normal and sickled hemoglobin protein

Thermodynamic properties of sickled and normal hemoglobin protein are considered within the framework of classical molecular dynamics. Here we have studied the specific heat capacity and RMSD (Root Mean Square Deviation) of both types of hemoglobin protein. Our investigation reveals that the specific heat capacity and RMSD for oxygenated hemoglobin protein is higher than those of de-oxygenated sickle hemoglobin protein. It is also observed that the specific heat capacity and RMSD values of sickle hemoglobin protein decrease with a rise in temperature.
 BIBECHANA 18 (2021) 140-148

CHARACTERISTIC ANALYSIS OF HOT DRY ROCK DAMAGE AND FAILURE UNDER THERMAL SHOCK

Wave propagation and thermal conduction properties can indicate structural damage to hot dry rock (HDR) caused by thermal shocks. Granite from the central paleo-uplift belt in the Daqing area in the northern Songliao Basin is the focus of this research. Wave propagation tests and thermal conduction tests were conducted on high-temperature specimens after natural cooling and water cooling. The influence of the cooling process with water on the apparent temperature and thermal shock velocity of rock masses is discussed. Changes in the P- and S-wave velocities, specific heat capacity, thermal diffusion coefficient, and thermal conductivity coefficient of specimens under different heat treatment conditions are analyzed and compared. The relationships between the wave propagation characteristics and the thermal conductivity values are established. The results indicate the following: (1) The apparent temperature and thermal shock velocity values of high-temperature rock masses show nonconstant rates of change from fast to slow. Rock masses with higher initial temperatures exhibit a continuous and strong thermal shock effect, and water temperature differences have only a limited effect on the thermal shock velocity over 20 s of cooling with water. (2) As the initial temperature increases or water temperature decreases, the P-wave velocity, S-wave velocity, thermal diffusion coefficient, and thermal conductivity coefficient values of high-temperature rock masses decrease overall, while the specific heat capacity values increase. The amplitude of change after water cooling is higher than that after natural cooling. When the initial temperature is below 100° C, the free water content is the main factor influencing the wave propagation characteristics and changes in the thermal conduction characteristics. When the initial temperature is greater than 300° C, the changes in both properties depend on the amount of thermal damage done to the rock mass. (3) The fitting results suggest that the wave propagation and thermal characteristics are closely related, and the damage factors are strongly consistent. The deviation of fitting coefficients is mainly due to the limited development of fractures in the small-sized specimens. The research results provide a reference for studies on thermal damage in HDR in the geothermal development process, and a method to determine the in situ thermal conductivity of reservoirs is proposed.

Tribological and thermal properties of plasma nitrided Ti45Nb alloy

In this study, the effects of plasma nitriding surface treatment on the structural, tribological and thermal properties of Ti45Nb Beta alloy were investigated experimentally. Plasma nitriding process of Ti45Nb alloy was performed in 25% Ar-75% N2 gas mixture, for treatment times of 1–4 hours at the temperatures of 700–750 °C. The tribological tests of the plasma nitrided alloy were performed in dry sliding conditions. Thermal property measurements were applied to the plasma nitrided samples to determine their thermal conductivity and specific heat capacity. The TiNbN2 phase was observed in the compound layer formed after the nitriding process, and the compound layer and diffusion layer thicknesses increased depending on the nitriding temperature and duration. The highest microhardness was obtained for the sample nitrided at 750 °C for 4 hours and the hardness approximately twice increased compared to the untreated alloy. Due to its high surface hardness and nitride layer with sufficient thickness, the lowest wear rate was obtained for the nitrided sample under these conditions. As a result, the most effective parameter on the wear properties of Ti45Nb alloy after nitriding was determined as the process temperature. After the plasma nitriding process, thermal conductivity, thermal diffusion and specific heat capacity values decreased due to the formation of a nitride layer on the surface with a relatively lower thermal conductivity compared to the untreated alloy.

Mechanical, Thermal, and Moisture Buffering Properties of Novel Insulating Hemp-Lime Composite Building Materials.

Hempcrete is a sustainable biocomposite that can reduce buildings’ embodied energy while improving energy performance and indoor environmental quality. This research aims to develop novel insulating hemp-lime composites using innovative binder mixes made of recycled and low-embodied energy pozzolans. The characterization of composites’ mechanical and hygrothermal properties includes measuring compressive strength, splitting tensile strength, thermal conductivity, specific heat capacity, and moisture buffer capacities. This study also investigates the impact of sample densities and water content on compressive strength at different ages. The findings suggest that mixes with a 1:1 binder to hemp ratio and 300−400 kg/m3 density have hygrothermal and mechanical properties suitable for insulating infill wall applications. Hence, compressive strengths, thermal conductivity, and specific heat capacity values range from 0.09 to 0.57 MPa, 0.087 to 0.10 W/m K, and 1250 to 1557 J/kg K, respectively. The average moisture buffer value for all hempcrete samples of 2.78 (gm/m2 RH%) indicates excellent moisture buffering capacity. Recycled crushed brick pozzolan can enhance the hygrothermal performance of the hemp-lime composites. Thus, samples with 10% crushed brick have the lowest thermal conductivity considering their density and the highest moisture buffer capacity. The new formulas of hydrated lime and crushed brick have mechanical properties comparable to metakaolin and hydraulic lime formulas.

Analytical prediction of heat capacity of molten AgCl and CuCl with application to thermochemical Cu-Cl cycle for hydrogen production

To sustain our power-dependent world, there is a need for technological innovation in all aspects of science and engineering. Many times, thermophysical and material properties are not well defined for the specific application, which leads to implementing assumptions and approximations from the published data. In the thermochemical copper-chlorine (Cu-Cl) cycle for hydrogen (H2) production, heat is recovered from cuprous chloride (CuCl) molten salt and it is then reacted with hydrochloric acid (HCl) in stoichiometric proportions to produce the anolyte for the H2 production step of the cycle. However, the lack of precise thermophysical properties on CuCl heavily hinders the detailed investigations of heat recovery from the molten salt as it cools from 450 °C to 90 °C. In this paper a new method is developed to determine the thermophysical property of CuCl and silver chloride (AgCl) as the molten salts are changing phases to solid. This is achieved by correlating electrochemistry data with thermal data. A model that predicts the specific heat capacity during phase change process is developed based on the existing electromotive force (EMF) and thermal data from literature. Developed model shows the EMF derived specific heat capacity values of AgCl and CuCl are similar with a slight offset since they have similar EMF's at higher temperatures.

Water-paraffin dispersion systems: manufacturing and application

The paper presents the study results of the stability and heat storage capacity of paraffin-in-water phase change suspensions (PCSs) obtained by the homogenization of paraffin and water in the developed rotary hydrodynamic homogenizer. The optimal concentration of components for obtaining stable paraffin-in-water suspensions is found. It is shown that the stable PCSs in the form of pastes, gels, and liquids can be obtained depending on the concentration of water, paraffin, and the surface active agent (SAA) as well as its type. In addition, the scheme of the solar heating system with the heat storage tank where the PCS functions both as the heat transfer fluid and the heat storage media is presented. It is shown that the use of PCS in the domestic solar heating system allowed the heat storage capacity of the storage tank to be increased by 25% as a result of the high fusion heat of paraffin and the high value of the water specific heat capacity. The estimation of the saving rate from applying fluid PCS as a heat storage medium is also presented and discussed.

Determination of the through-plane thermal conductivity and specific heat capacity of a Li-ion cylindrical cell

Despite the high popularity of lithium-ion batteries there is still a lack of simple and easily applicable methods for determining the Li-ion cell thermal parameters. Information about the specific heat capacity and thermal conductivity of Li-ion cells is required to ensure appropriate operation of the thermal control system of the Li-ion battery, which prevents battery operation in an unacceptable temperature range. The method presented in this paper allows to simultaneously determine the specific heat capacity and through-plane thermal conductivity of any Li-ion cylindrical cell in a simple and inexpensive way with the help of temperature and heat flux measurements on the cell surface. Moreover, the method allows to estimate the temperature dependence of the thermal parameters under consideration. The applicability of the method is evaluated on the reference sample, whose thermal parameters are close to the thermal parameters of Li-ion cylindrical cells and well known. The slight deviation of the measured values of specific heat capacity and thermal conductivity from the reference values, being less than 0.5% and 3.2%, respectively, for all cases under study, confirms the applicability of the method for determination of the thermal parameters of cylindrical Li-ion cells. Therefore, the method is applied to measure the thermal parameters of 18650-type and 26650-type cylindrical Li-ion cells at different values of temperature and SoC. The uncertainty analysis of the proposed method allows to give recommendations to achieve a high accuracy of thermal parameter determination.

A comprehensive DFT study on the adsorption of tetryl on the surface of graphene

In this research study, computational simulation was used to study the adsorption of tetryl on the surface of graphene. For this purpose, the structures of graphene, tetryl and their complexes were optimized geometrically. Then, IR and Frontier molecular orbital calculations were implemented at 298-398 K at the intervals of 10°. The obtained thermodynamic parameters including, Gibbs free energy (ΔGad), adsorption enthalpy alterations (ΔHad), and thermodynamic equilibrium constants (Kth) revealed the adsorption of tetryl is exothermic, spontaneous, non-equilibrium, and experimentally feasible at the both evaluated configurations. The influence of temperature on the thermodynamic factors of the desired process was also evaluated and the results indicated that the 298.15 K was the best temperature for the graphene interaction with tetryl. The calculated specific heat capacity (CV) values revealed that the sensitivity of the produced graphene-tetryl complexes to the heat and shock have declined significantly. The increased nitrogen-oxygen bond lengths after the adsorption of tetryl to the surface of graphene exhibited that the explosive and destructive power of tetryl-graphene derivatives was higher than that of the pure tetryl. Some HOMO-LUMO related parameters such as energy gap, electrophilicity, chemical hardness, maximum transferred charge index (ΔNmax), and chemical potential were also calculated and discussed in details.

Reservoir simulation of Ulumbu geothermal field using TOUGH2 and ITOUGH2 simulator

Ulumbu geothermal field is classified as a natural two-phase geothermal system, located in the south of Mandosawu - Ranakah Old volcanics and Pocoleok, Flores Island. This field produces 4 x 2.5 MW electric power in 2014 until now with temperature between 230–240 °C. This study aims to perform reservoir simulation in the Ulumbu field. The reservoir simulation method aims to determine the reservoir characteristics of the geothermal field. This research used TOUGH2 and ITOUGH2 simulator to simulate the reservoir. The work concept from TOUGH2 is forward modeling while ITOUGH2 is inverse modeling. Both of methods will produce an output. The output of this research is natural state model that was validated by three wells of the actual measurement (pressure and temperature) and heat flow from the conceptual model. A pressure and temperature profiles are very representative with the data in the three wells. The reservoir location is between Poco Leok and Poco Rii (upflow zone) and continues to the southwest (outflow zone) with an average area of 10.5 km2. The top reservoir is at an elevation of 500 m, while the depth is up to -2000 m. Reservoir rock has a permeability value of around 10−14–10−15 m2, porosity value of 8–10 %, density value of 2500 kg/m3, and specific heat capacity value of 900 J/kgK. Temperature distribution results of the natural state model show the hydrogeological profile of the Ulumbu geothermal system. The natural state model is then used to help undertake a geothermal field development scenario, that is, to calculate resource reserves and to make recommendations for subsequent drilling zones.

On the use of boundary conditions and thermophysical properties of nanoparticles for application of nanofluids as coolant in nuclear power plants; a numerical study

In the first part of the present study, a thermal-hydraulic subchannel code hereafter called ‘SUBTHAC’ is developed to evaluate the enhancement effects of nanoparticles in core heat transfer. The first version of SUBTHAC (V1.0) can analyze the steady state flow of coolant with Al2O3, TiO2 or CuO as nanoparticles (other types of nanoparticles can be added by the user). Different output profiles can be selected such as fluid temperature, pressure and velocity for each subchannel, clad outside temperature for each fuel rod, axial and lateral mass flow, etc. SUBTHAC uses a dedicated algorithm to solve the subchannel equations and, unlike many other codes, allows for thermophysical parameters of nanoparticles to be a function of the temperature, leading to improvement the accuracy of results. Results computed by SUBTHAC for base fluid (pure water) are validated against those obtained by COBRA-EN code. In the next step, with the aim of validating the capability of nanofluid analysis of SUBTHAC code, its nanofluids results have been validated against reference CFD simulations. After the validation, comprehensive numerical comparisons are conducted to assess the enhancement of thermal-hydraulic parameters by using nanofluids. It is shown that, among Al2O3, TiO2 and CuO nanofluids with volumetric concentration in the range of 1–5%, TiO2-3% and CuO-3% are the best choices to increase fluid outlet temperature and decrease clad temperature, respectively. Using nanofluids with a concentration higher than 3% volumetric is not justifiable as the core pressure drop increases up to more than 20%.In the second part of the manuscript, some relevant remarks are put forward on the assignment of boundary conditions (BC, i.e. inlet velocity/inlet mass flux/inlet Reynolds number) and the adoption of reliable values for specific heat capacity of nanoparticles in operational temperature of NPPs. The effects of using the above boundary conditions and incorrect values of the specific heat (as adopted in the literature so far) are depicted by presenting some profiles of coolant and clad temperature. Selecting different BCs and incorrect values of specific heat for nanoparticles can jeopardize the results of calculations.

Evaluation of Properties of Composite Panels Fabricated from Waste Newspaper and Wood Dust for Structural Application

In this work, dry forms of waste newspaper pulp, untreated wood dust and treated wood dust were used at varying weight proportions to fabricate composite panels which thenafter served as test samples. With increase in the content of either the untreated wood dust or the treated wood dust in the developed panels, the results showed increase in the mean values of bulk density, thermal conductivity, thermal diffusivity, flexural strength but decrease in the mean values of specific heat capacity and percentage water absorption. Also, at p < 0.05, significant differences were revealed in the mean values of bulk density and specific heat capacity between the results obtained for samples with untreated wood dust content and those associated with samples containing the treated wood dust. Again, samples containing the untreated wood dust were found to be better thermal insulators but with lower flexural strength than those of same proportions of the treated wood dust component. From application viewpoint, the findings in this work indicated that the fabricated samples could compete favorably with conventional materials commonly used for thermal insulation in buildings. It is, therefore, obvious that recycling waste newspaper and wood dust into such panels can help to reduce the adverse effect of the waste materials on environment also improve economy by providing building sector with low-cost and environmentally-friendly insulation materials suitable for internal building design.

Adsorption of lomustin anticancer drug on the surface of carbon nanotube: A theoretical study

The present study aimed to assess the adsorption of Lomustin on the single-walled carbon nanotube which has been examined using Density Functional Theory (DFT), agent in a solvent phase (water) at the B3LYP/6-31G (d) theoretical level. Initially, the structures of Lomustin, carbon nanotube, and Lomustin complexes with carbon nanotubes were designed in Gauss View in three different conformers and were optimized geometrically, on which IR and frontier molecular orbital computations were carried out. Adsorption energy values, Gibbs free energy changes (ΔGad), adsorption enthalpy changes (ΔHad), and equilibrium thermodynamic constants were estimated. The results showed that adsorption process was spontaneous, exothermic and non-equilibrium. The values of specific heat capacity and adsorption enthalpy indicate that this nanostructure can be used to build new thermal sensors to measure Lomustin. The results of molecule orbitals estimations showed that energy gap, after drug absorption on the nanotube surface, decreased significantly and the values of chemical hardness and dipole moment were studied after the interaction of drug with adsorbent and the results showed that drug solubility and reactivity, after adsorption on carbon nanotubes, increased significantly. According to the obtained results for adsorption of Lomustin, this nanostructure can be used as a sensing material in building new electrochemical sensors to measure this drug.

Boron nitride nanocone as an adsorbent and senor for Ampicillin: A Computational Study

In this research, the performance of boron nitride nanocone for the detection and removal of ampicillin was investigated by infra-red (IR), natural bond orbital (NBO), frontier molecular orbital (FMO) computations. The calculated values of adsorption energy showed the interaction of ampicillin with BN nanocone is experimentally possible. The calculated values of Gibbs free energy and thermodynamic equilibrium constant showed the adsorption process is spontaneous and irreversible. The calculated values of enthalpy changes and specific heat capacity showed ampicillin adsorption is exothermic and BN nanocone can be used for the construction of a new thermal sensor for the detection of ampicillin. The effect of temperature on the thermodynamic parameters was also evaluated and the results indicated ampicillin adsorption is more favorable in room temperature. The NBO results demonstrated in both of the studied configurations a monovalent chemical bond is formed between the nanostructure and the adsorbate and the interaction process is chemisorption. The DOS spectrums showed the bandgap of BN nanocone increased from 1.888 (eV) to 7.030 (eV) which proved this nanomaterial is an appropriate electrochemical sensing material for detection of ampicillin. Some important structural parameters such as dipole moment, electrophilicity, maximum charge capacity, chemical hardness and chemical potential were also calculated and discussed in detail.

Adsorption of 3-picrylamino-1,2,4-triazole on C60 surface as a green fuel: DFT studies

In this study, the adsorption of 3-picrylamino-1,2,4-triazole (PATO) On the surface of fullerene (C60) was evaluated by density functional theory using, Becke, three-parameter and Lee-Yang-Parr (B3LYP). PATO as a green fuel, is such a green material and environmental friendly, because after combustion it produces excessive amounts of N2 gas. Due to the importance of these materials in protecting environmental pollution as well as protecting fossil fuel reserves, it is necessary to research in this field. For this purpose, the structures of PATO, C60, and the PATO-C60 complexes were optimized geometrically. Then, IR and Frontier molecular orbital calculations were performed on them. The calculated energies: Gibbs free energy changes (ΔGad) and adsorption enthalpy changes (ΔHad) revealed that the adsorption process of PATO-C60 complexes are experimentally feasible, spontaneous and exothermic. The specific heat capacity values (CV) showed the heat sensitivity has reduced significantly in the PATO-C60 complexes. The N‒O and C‒N bond lengths and the density values demonstrated that PATO-C60 complexes have higher explosive velocity and blasting pressure in comparison to the pure blasting materials without C60. The Frontier molecular orbital parameters such as band gap, chemical hardness, electrophilicity, chemical potential and charge capacity were also studied.

Long-chain Diesters of Fattyy Alcohols as Novel Phase Change Materials for Thermal Energy Storage

In this study, long chain diesters of fatty alcohols were synthesized for use in thermal energy storage applications. Long-chain diesters of adipic acid were proposed for the first time in this study to be used as phase change material (PCM). For this purpose, ditetradecyl adipate (DTA) and dioctadecyl adipate (DOA) were synthesized as novel solid-liquid PCMs by means of the direct esterification reaction of adipic acid with 1-tetradecanol and 1-octadecanol. The reaction was yielded at around 90% as an average at the end of 6 hours. The DTA and DOA were characterized chemically using FT-IR and 1HNMR techniques as the energy storage properties, total enthalpy, and specific heat (Cp) capacity values were determined by DSC analysis. Melting temperatures and enthalpies of DTA and DOA were measured as 44 and 60 C respectively; and 142.4 and 186.2 Jg-1 respectively. Total enthalpy calculation showed the latent heat storage capacity along with sensible heat capacity of fatty alcohols and long-chain diesters between 0 and 80 C. Cp values of fatty alcohols and long-chain diesters also calculated for solid and liquid phase separately. TGA analysis was performed to determine thermal stability of the esters. DTA and DOA compounds were found stable up to 248.3 and 342.5 C respectively. Thermal cycling test was applied to the materials and it was found that DTA and DOA are both found stable after 1000 times accelerated thermal cyclings. According to the results obtained, DTA and DOA with high energy storage capacity are promising to be used as new solid-liquid PCMs in thermal energy storage applications for medium temperature applications.

Measurement and analysis of specific heat capacity of lead-bismuth eutectic

The lead-cooled fast reactor is a fourth-generation nuclear system with great development potential. Lead-bismuth eutectic (LBE) is used as the coolant of lead-cooled fast reactor, and specific heat capacity of LBE is a necessary parameter for studying the heat transfer in the primary loop. However, the experimental data on specific heat capacity of LBE are limited. There are only three independent data could be found in open literature, and the measurement error of the existing data is about 5%~7%. In this paper, specific heat capacity of LBE at 30–600 °C is studied by differential scanning calorimetry and the reliability and uncertainty of the data are analyzed. The recommended value of LBE's specific heat capacity at 150–600 °C is 0.1342–0.1495 J kg−1 °C−1. The results show that the measurement error of this method is about 0.62%, the maximum composite uncertainty of LBE's specific heat capacity is 1.83%, and the expanded uncertainty is 3.66% (k = 2). The experimental data have high reliability and can provide data support for thermal-hydraulic design in lead-cooled fast reactor.

ASSESSING THE SUITABILITY OF TIGER NUT FIBRE FOR STRUCTURAL APPLICATIONS

In this work, the properties of the composite produced from waste carton with various tiger nut fibre contents having cassava starch slurry as binder were investigated. The results obtained showed the ranges of the mean thermal conductivity, bulk density, specific heat capacity, thermal diffusivity, thermal absorptivity, nailability, flexural strength and compressive strength values to be (0.0447 – 0.0603) Wm-1K-1, (683.62 – 746.32) kgm-3, (1439.811 – 1840.554) J/kg/K, (5.612 - 3.553) 10-8 m2s-1, (25.456 – 31.993) m-1, (23.9 – 100)%, (1.58 – 1.86) MPa and (2.16 – 2.78) MPa respectively between 8.3% and 43.1% of the fibre content. It was generally observed that with a choice variation in the fibre content, the performance of the developed board can be optimized for structural applications. Hence, instead of discarding the fibre as waste, recycling it can help to provide raw material for the production of cost effective and environmentally friendly materials. This will in turn reduce health risk caused by environmental pollution due to improper waste disposal practice of such material.

Optimization of Continuous Solid-State Distillation Process for Cost-Effective Bioethanol Production

To improve the efficiency of bioethanol production, an advanced process was required to extract ethanol from solid-state fermented feedstock. With regard to the characteristics of no fluidity of solid biomass, a continuous solid-state distillation (CSSD) column was designed with a proprietary rotary baffle structure and discharging system. To optimize the operation condition, fermented sweet sorghum bagasse was prepared as feedstock for a batch distillation experiment. The whole distillation time was divided into heating and extracting period which was influenced by loading height and steam flow rate simultaneously. A total of 16 experiments at four loading height and four steam flow rate levels were conducted, respectively. Referring to packing, rectifying column, mass, and heat transfer models of the solid-state distillation heating process were established on the basis of analyzing the size distribution of sweet sorghum bagasse. The specific heat capacity and thermal conductivity value of fermented sweet sorghum bagasse were tested and served to calculate the ethanol yielding point and concentration distribution in the packing. The extracting process is described as the ethanol desorption from porous media absorbent and the pseudo-first-order desorption dynamic model was verified by an experiment. Benefit (profit/time) was applied as objective function and solved by successive quadratic programming. The optimal solution of 398 mm loading height and 8.47 m3/h steam flow rate were obtained to guide a 4 m in diameter column design. One heating and two extracting trays with 400 mm effective height were stacked up in an industrial CSSD column. The steam mass flow rate of 0.5 t/h was determined in each tray and further optimized to half the amount on the third tray based on desorption equation.