Process Thermal Efficiency Research Articles

Experimental investigation of the influence of pre-chamber structural parameters on combustion and emission characteristics of a high compression ratio SI engine

The passive pre-chamber exhibits great potential for practical applications in the internal combustion engine due to its simple structure. However, it faces difficulties in scavenging process, making optimization of pre-chamber structure particularly important. In this study, the effects of pre-chamber ignition systems with different structures and original spark ignition were conducted on a high compression ratio direct-injection SI engine to investigate the combustion, performance, and emission characteristics. The results show that the increase in pre-chamber volume weakens the in-cylinder combustion process and engine performance, while increasing the pre-chamber orifice diameter can enhance the combustion stability at medium to high loads, but will weaken the engine performance at low load. Compared to spark ignition, pre-chamber ignition results in an earlier 50% combustion position, a shorter combustion duration and lower COVIMEP, with these effects becoming stronger as load increases. At high load, the pre-chamber ignition (PC1) advances the 50% combustion position by 5.6°CA and shortens the combustion duration by 16.7%. In addition, the indicated thermal efficiency of the pre-chamber ignition achieves an increase of 0.84% at the optimal point and 2.5% at high load. Overall, using the smaller orifice diameter and volume in the pre-chamber can improve in-cylinder combustion process and increase thermal efficiency across the load range. For emission analysis, the pre-chamber ignition leads to an increase in NOx and HC emissions due to the influence of in-cylinder combustion temperature and quenching effect, while the CO emissions are similar to spark ignition.

Development of photovoltaic-thermal using attachable solar collector based on on-site construction

Photovoltaic–thermal (PVT) module that can generate thermal and electrical energy have been proposed for the realization of zero energy buildings. However, the high initial investment cost is deterred consumers adoption and is delayed its application in buildings. To address these limitations, this study proposed the PVT module with an attachable solar collector (PVT–ASC) that can construct on-site and has a simple manufacturing process to reduce the initial investment cost. The ASC was design as appropriate product in the commercialization based on computational fluid dynamic results and manufacturing costs. To evaluate the feasibility of the PVT–ASC, thermal efficiency, structural stability, economics, and environmental benefits are compared with commercial products. The thermal efficiency of the PVT–ASC was evaluated through field test and calculated to be 41 %. The PVT–ASC demonstrated the potential to become a marketable product due to its streamlined manufacturing process and comparable thermal efficiency to conventional commercial products. Furthermore, the economics and environmental benefits of the PVT–ASC were evaluated through comparison with commercial products considering disassembly, manufacturing, transportation and installation works. As the results, the PVT–ASC reduced total cost and CO2 emissions as 39 % (3820 USD) and 28 % (229kgCO2eq), respectively, compared to commercial products. These benefits of PVT–ASC in comparison to commercial products were expected to grow as transportation distances lengthened and building scale increased. The results of this study offered as low-cost and low-emissions technologies to facilitate the use of PVT modules in building applications.

Comprehensive evaluation of an ionic liquid based deep purification process for NH3-containing industrial gas

Ammonia (NH3) emission has caused serious environment issues and aroused worldwide concern. The emerging ionic liquid (IL) provides a greener way to efficiently capture NH3. This paper provides rigorous process simulation, optimization and assessment for a novel NH3 deep purification process using IL. The process was designed and investigated by simulation and optimization using ionic liquid [C4im][NTF2] as absorbent. Three objective functions, total purification cost (TPC), total process CO2 emission (TPCOE) and thermal efficiency (ηeff) were employed to optimize the absorption process. Process simulation and optimization results indicate that at same purification standard and recovery rate, the novel process can achieve lower cost and CO2 emission compared to benchmark process. After process optimization, the optimal functions can achieve 0.02726 $/Nm3 (TPC), 311.27 kg CO2/hr (TPCOE), and 52.21% (ηeff) for enhanced process. Moreover, compared with conventional process, novel process could decrease over $ 3 million of purification cost and 10000 tons of CO2 emission during the life cycle. The results provide a novel strategy and guidance for deep purification of NH3 capture.

Multi-objective optimization of CO2 emission and thermal efficiency for on-site steam methane reforming hydrogen production process using machine learning

Currently, hydrogen is produced primarily through steam methane reforming , a gray hydrogen production process that generates CO 2 as a by-product. Thus, it is crucial to optimize the process thermal efficiency with minimizing CO 2 generation in a hydrogen production process. This study focuses on the multi-objective optimization of low-carbon hydrogen production process, considering both process thermal efficiency maximization and CO 2 emission minimization. To this end, a hybrid deep neural network model is developed to increase the robustness of the multi-objective optimization. The developed hybrid deep neural network model is incorporated into a proposed multi-objective particle swarm optimization algorithm that performs Pareto dominance-based multi-objective optimization. In experiments conducted, Pareto-optimal solutions with thermal efficiency distribution between 77.5 and 87.0% and CO 2 emissions between 577.9 and 597.6 t/y were obtained. Furthermore, the Pareto-optimal front was analyzed to provide various representative solutions to assist decision-makers. The findings of this study can enable efficient and flexible process operations according to various requirements. • Low-carbon hydrogen production from an on-site steam methane reforming process. • Multi-objective optimization of thermal efficiency and CO 2 emission simultaneously. • Multi-objective particle swarm optimization for Pareto dominance-based optimization.

Advanced Steam Reforming of Bio-Oil with Carbon Capture: A Techno-Economic and CO2 Emissions Analysis

A techno-economic analysis has been used to evaluate three processes for hydrogen production from advanced steam reforming (SR) of bio-oil, as an alternative route to hydrogen with BECCS: conventional steam reforming (C-SR), C-SR with CO2 capture (C-SR-CCS), and sorption-enhanced chemical looping (SE-CLSR). The impacts of feed molar steam to carbon ratio (S/C), temperature, pressure, the use of hydrodesulphurisation pretreatment, and plant production capacity were examined in an economic evaluation and direct CO2 emissions analysis. Bio-oil C-SR-CC or SE-CLSR may be feasible routes to hydrogen production, with potential to provide negative emissions. SE-CLSR can improve process thermal efficiency compared to C-SR-CCS. At the feed molar steam to carbon ratio (S/C) of 2, the levelised cost of hydrogen (USD 3.8 to 4.6 per kg) and cost of carbon avoided are less than those of a C-SR process with amine-based CCS. However, at higher S/C ratios, SE-CLSR does not have a strong economic advantage, and there is a need to better understand the viability of operating SE-CLSR of bio-oil at high temperatures (>850 °C) with a low S/C ratio (e.g., 2), and whether the SE-CLSR cycle can sustain low carbon deposition levels over a long operating period.

Simultaneous analysis of hydrogen productivity and thermal efficiency of hydrogen production process using steam reforming via integrated process design and 3D CFD modeling

Steam methane reforming (SMR) is a widely adopted method for H2 production due to its advantages in the maturity of technology and economic feasibility. Since the optimization of an SMR reactor in the overall H2 production process is important to reduce energy loss and increase productivity, the analysis of the reactor is essential. However, in order to increase the efficiency of the entire H2 production process, it is necessary to analyze the entire process in an integrated manner rather than focusing on an SMR reactor. To this end, we develop a computational fluid dynamics (CFD) model of the SMR reactor and integrate it with the H2 production process based on experimental data, to simultaneously evaluate the H2 productivity and process thermal efficiency. The reactor yield and process efficiency according to operating conditions were evaluated by combining the exact rate of heat transfer of the SMR reactor into process simulation. The integration model achieved higher accuracy of modeling the process than the individual modeling of the SMR reactor and the H2 production process. From the parametric study via the integration model, the most advantageous set of operating conditions of the H2 production process is proposed.

Exothermicity of hydrothermal carbonization: Determination of heat profile and enthalpy of reaction via high-pressure differential scanning calorimetry

Hydrothermal carbonization (HTC) is known for being exothermic, an aspect that can lower the external energy demand necessary to face thermal losses and therefore be conducive to the overall HTC process thermal efficiency. Also, heat profiles can help explore kinetics and generally provide an insight into the HTC process. Despite the potential of the HTC exothermicity, only a few studies examined it and with different methodologies. This work aims to deepen this aspect by exploring heat profiles, enthalpy of reaction, and comparing two experimental methods by performing an experimental campaign using a power-compensated high-pressure differential scanning calorimeter (DSC). Three substrates (glucose, cellulose, and grape seeds) were hydrothermally carbonized at 180, 200, 220, and 250 °C at a biomass to water mass ratio of 0.25. To determine net heat profiles and enthalpies, water thermal effects were removed using two approaches, consisting of running a thermal program on the water alone or the exhaust, i.e. the products after the reaction. An instrument baseline considering both a zero-line and a time-drift was considered. Results show that both methods allow inferring similar enthalpy values at low operating temperature, while at high temperature a difference in the heat capacity of the liquid phase (due to the production of compounds dissolved in the liquid phase and absorbed on the solid) can affect the results related to the exhaust approach. In both cases, higher temperatures favor the exothermic peak intensity, the curve sharpening, and the increase (in absolute value) of reaction enthalpies. These are in the ranges −0.20 ÷ −0.86 MJ/kg, −0.61 ÷ −1.33 MJ/kg, and −0.42 ÷ −1.53 MJ/kg for glucose, cellulose, and grape seeds, respectively.

Assessment of pilot direct contact membrane distillation regeneration of lithium chloride solution in liquid desiccant air-conditioning systems using computer simulation.

Membrane distillation (MD) has been increasingly explored for treatment of various hyper saline waters, including lithium chloride (LiCl) solutions used in liquid desiccant air-conditioning (LDAC) systems. In this study, the regeneration of liquid desiccant LiCl solution by a pilot direct contact membrane distillation (DCMD) process is assessed using computer simulation. Unlike previous experimental investigations, the simulation allows to incorporate both temperature and concentration polarisation effects in the analysis of heat and mass transfer through the membrane, thus enabling the systematic assessment of the pilot DCMD regeneration of the LiCl solution. The simulation results demonstrate distinctive profiles of water flux, thermal efficiency, and LiCl concentration along the membrane under cocurrent and counter-current flow modes, and the pilot DCMD process under counter-current flow is superior to that under cocurrent flow regarding the process thermal efficiency and LiCl concentration enrichment. Moreover, for the pilot DCMD regeneration of LiCl solution under the counter-current flow, the feed inlet temperature, LiCl concentration, and especially the membrane leaf length exert profound impacts on the process performance: the process water flux halves from 12 to 6 L/(m2·h) whilst thermal efficiency decreases by 20% from 0.46 to 0.37 when the membrane leaf length increases from 0.5 to 1.5 m.

Optimisation of a sorption-enhanced chemical looping steam methane reforming process

An intensified hydrogen production steam reforming process named ‘Sorption-Enhanced Chemical Looping Steam Methane Reforming’ (SE-CL-SMR) was studied. Aspen Plus was used to carry out a thermodynamic investigation into the influence of various operating conditions on hydrogen production and process thermal efficiency. The steam to carbon molar ratio (S/C), the CaO to carbon molar ratio (CaO/C), the metal oxide to carbon molar ratio (MeO/C), the metal oxide composition (NiO:CuO), and the oxidising agent species were all shown to influence the process performance.The main findings were that; (1) the introduction of CaO reduces the potential for coke formation with predicted zero coke formation for CaO/C ratios > 0.4; (2) increasing amounts of metal oxide (MeO/C) and steam (S/C) enhance the hydrogen production yield and purity; (3) due to its involvement in an exothermic reaction, the presence of CuO allows for the reforming reactor to operate as an adiabatic reactor with an operating temperature within the range of 600 °C–700 °C; (4) an increase in the NiO:CuO ratio leads to an increase in methane conversion.With the operating conditions of S/C = 3, CaO/C = 1, MeO/C = 1, NiO:CuO = 0.9 and air as the oxidising agent, a hydrogen purity as high as 98% was predicted for the SE-CL-SMR process, along with the lowest observed CO2 production rate. Under the same conditions and using pinch analysis, the thermodynamic model prediction of the thermal process efficiency is reported as ca. 86%. This is significantly higher than the reported efficiency of 79% for the ‘Sorption-Enhanced Steam Methane Reforming’ (SE-SMR) process, predicted using similar thermodynamic models.

Machine learning-based energy optimization for on-site SMR hydrogen production

The production and application of hydrogen, an environmentally friendly energy source, have been attracting increasing interest of late. Although steam methane reforming (SMR) method is used to produce hydrogen, it is difficult to build a high-fidelity model because the existing equation-oriented theoretical model cannot be used to clearly understand the heat-transfer phenomenon of a complicated reforming reactor. Herein, we developed an artificial neural network (ANN)-based data-driven model using 485,710 actual operation datasets for optimizing the SMR process. Data preprocessing, including outlier removal and noise filtering, was performed to improve the data quality. A model with high accuracy (average R2 = 0.9987) was developed, which can predict six variables, through hyperparameter tuning of a neural network model, as follows: syngas flow rate; CO, CO2, CH4, and H2 compositions; and steam temperature. During optimization, the search spaces for nine operating variables, namely the natural gas flow rate for the feed and fuel, hydrogen flow rate for desulfurization, water flow rate and temperature, air flow rate, SMR inlet temperature and pressure, and low-temperature shift (LTS) inlet temperature, were defined and applied to the developed model for predicting the thermal efficiencies for 387,420,489 cases. Subsequently, five constraints were established to consider the feasibility of the process, and the decision variables with the highest process thermal efficiency were determined. The process operating conditions showed a thermal efficiency of 85.6%.

Ionic liquid screening for CO2 capture and H2S removal from gases: The syngas purification case

A systematic ionic liquid (IL) screening approach for acid gas removal processes was developed by taking into account a wide range of process performance-determining factors. Selective and non-selective absorption of CO2 and H2S from syngas in conceptual low- and high-temperature processes was investigated to explore the optimal solvents, among 5980 ILs, for each process. Making use of the COSMO-RS and other suitable IL-systems predictive models, the process thermal efficiency (absorption enthalpy and sensible heat) and absorption–desorption working capacity were addressed in the selection of IL candidates along with the primary factors such as solubilities and selectivities. Meanwhile, the COSMO-RS predicted results were validated, and σ-profile and σ-potential of CO2, H2S, H2, CO and the featured ILs were analyzed to provide theoretical insights into intermolecular interactions between gas and IL. The same IL screening method can be extended to CO2 capture and H2S removal from natural gas, biogas, and other sources.

Production of instant coffee from cold brewed coffee; process characteristics and optimization

This study aimed to develop a process for producing instant coffee from cold brewed Arabica and Robusta roasted coffee beans. The process starts by selecting an appropriate mixture of Arabica and Robusta coffee beans, degree of roasting (light, medium, dark) and degree of grinding (coarse, fine). Sensory evaluation by a trained panel showed that a mixture of 92.5% Arabica and 7.5% Robusta medium roasted, coarsely ground coffee beans produces instant cold brewed coffee equally or better accepted from other instant coffees available to consumers. The selected coffee beans were subjected to vacuum assisted cold extraction and the extract was spray dried. Spray drying conditions (inlet temperature, air volumetric flow and air aspiration rate) were optimized by a 33 full factorial design. Response variables were solids yield, process thermal efficiency and anti-oxidant capacity of the produced powder measured as %DPPH scavenging ability, FRAP and total phenolic content. The produced powder was analysed for its physicochemical characteristics (caffeine content, phenolics, moisture content, hygroscopicity, bulk density, solubility, particle size distribution, acrylamide content and shelf life determination).

3-D numerical investigation on commercial PTFE membranes for membrane distillation: Effect of inlet conditions on heat and mass transfer

Computational fluid dynamics (CFD) techniques were implemented to develop a 3-D numerical model to investigate the effect of several inlet conditions on the heat and mass transfer through a commercial PTFE membrane in a specific direct contact membrane distillation (DCMD) cell design. The model was validated against other researchers’ results and was found to have a good arrangement. The model was then used to predict the effects of changing the direction of the flow, inlet Reynolds number and feed inlet temperature on the permeate flux through the membrane and the process thermal efficiency. It has been found that changing the flow arrangement from parallel to counter flow slightly increased the permeate flux. Changing the inlet Reynolds number from 25 to 50 significantly increased the permeate flux and the process thermal efficiency, while raising it from 50 to 150 had little to no effect. It has also been found that increasing the feed inlet temperature from 303 K to 323 K almost tripled the permeate flux.

Impact of operating conditions on a single droplet and spray drying of hydroxypropylated pea starch: Process performance and final powder properties

AbstractFor an efficient production of spray‐dried fine powders having controllable properties (size, size distribution, and morphology), finding suitable operating conditions and an appropriate initial composition of the fluid material is important. For this purpose, a suspension device is employed to investigate the drying kinetics of a single droplet of hydroxypropylated pea starch (HPS). In the current work, the effect of the drying air temperature (80–160°C) and of the initial solid content of the agent (15–30%w/w) on the drying kinetics, shrinkage, and locking point of a single droplet was systematically investigated to acquire the optimal conditions required for producing HPS powder using a pilot‐scale spray dryer. In addition to the previously mentioned parameters, the atomization pressure effect (2–3 bars) on the spray‐drying process yield, thermal efficiency, and final powder properties were also considered. A laboratory‐scale X‐ray microtomograph and a camsizer‐XT were employed for the acquisition of three‐dimensional images and surface morphology of single dried particles and spray‐dried powder, respectively. Hollow particles were obtained in all single droplet experiments. The drying kinetic study results were supported by those obtained by the spray drying of HPS. An increased temperature of the drying air and the initial solid content of the solution results in higher powder recovery, lower residual moisture content, and larger particle size. Otherwise, the final particles are larger at a decreased atomization pressure. The optimized parameters for the high spray‐drying process yield (24.54%; 3 bars, 140°C, 25 wt%) and better powder homogeneity (span = 2.31; 3 bars, 140°C, 20 wt%) were defined. A mixture of particle morphologies was observed among the different final powders. A broken shell corresponding to rigid particles was obtained at a drying temperature of 140°C and an initial solid content of 25 wt%. A nonbroken particle refers to a pliable particle that corresponds to inflated and collapsed particles dried at high and low drying temperatures.

Thermodynamic analysis of chemical looping gasification coupled with lignite pyrolysis

A poly-generation system integrating coal pyrolysis and chemical looping gasification (CLG) is proposed to realize the multi-generation of value-added chemicals, synthetic gas fuels and heat/electricity. In this system, the models including coal pyrolysis, coal drying, air reactor (AR) and fuel reactor (FR) are employed to simulate the coupled system using Aspen Plus software. Especially, the FR model is used to produce syngas, which is the main target product, on the basis of Gibbs free energy minimization approach. According to the thermodynamic data obtained from the simulation, chemical exergy and physical exergy are determined for process streams and thermal efficiency is discussed as well. The overall energy efficiency of the new system can achieve values of 43.12%, with the drying unit causing the highest energy destruction. The results indicate that the coupled system shows a better performance compared with its original individual processes in consideration of the thermodynamic efficiency and effects on the environment, though the additional mechanical energy consumption occurs in the new system. Moreover, being used as the gasification agent in the FR, phenol wastewater has been greatly reduced, which reduces levels of environmental pollution. Hence, this new system will be of great potential in industrial application due to its high energy utilization efficiency and low pollution.

Conceptual design of the iodine–sulfur process flowsheet with more than 50% thermal efficiency for hydrogen production

A conceptual design of a practical large-scale plant of the thermochemical water splitting the iodine–sulfur (IS) process flowsheet was carried out as a heat application of Japan Atomic Energy Agency’s commercial Gas Turbine High Temperature Reactor 300 MW for Cogeneration (GTHTR300C) plant design. Innovative techniques proposed by JAEA were applied for improvement of hydrogen production thermal efficiency; depressurized flash concentration of H2SO4 using waste heat from Bunsen reaction, prevention of H2SO4 vaporization from a H2SO4 distillation column by introduction of H2SO4 solution from the 2nd flash bottom, and I2 condensation heat recovery by direct contact heat exchange in an HI distillation column. A simulation of material and heat balance was made using PRO/II, a commercial chemical process simulator. The result demonstrated that hydrogen of about 31,900 Nm3/h would be produced by 170 MW heat from the GTHTR300C. A process thermal efficiency of 50.2% would be achievable with incorporation of the innovative techniques and the following high performance components expected in future R&D; an electro-electrodialysis cell stack, a reverse osmosis membrane, a HI decomposition reactor incorporated with a H2 permselective membrane, and heat exchangers.

Assessing the performance of solar thermal driven membrane distillation for seawater desalination by computer simulation

A computer model was developed to simulate the performance of an integrated solar thermal driven direct contact membrane distillation (DCMD) system for seawater desalination using recorded weather data. The results highlight the importance of simulating the DCMD process together with the energy source. Indeed, when considered in isolation from the thermal energy source, increasing water cross flow velocities in the feed and distillate channels results in an increase in water flux and thermal efficiency of the DCMD module. By contrast, when coupling the DCMD module with the solar thermal collector, increasing water cross flow velocities reduces both the process water flux and thermal efficiency. This is because of the limited supply of solar thermal at any given time, and hence the feed temperature decreases when cross flow velocities increase. Thus, any benefits in the reduction of temperature polarisation due to increasing cross flow velocities are overwhelmed by the effects of feed temperature decrease on water flux and thermal efficiency. Results from our simulation also demonstrate the viability of the solar thermal driven DCMD process for small-scale seawater desalination applications. Distillate production is dependent on the availability of solar radiation during the day; nevertheless, a small system with a 7.2m2 spiral-wound DCMD module and a 22.6m2 flat plate solar thermal collector can produce over 140kg of distillate each day under real weather conditions. This is equivalent to a daily distillate production rate of 19.7kg per m2 of membrane or 6.3kg per m2 of solar thermal collector.

Методика определения режимов послойной электронно-лучевой наплавки проволоки для аддитивных технологий

Electron beam wire feed deposition is a process that uses an electron beam as a power source and wire as raw material to fabricate metallic items in a vacuum chamber. This technology can be widely used for industrial applications due to its ability of using metal in a very efficient manner, making parts within a short period of time, and ensuring good quality of the produced items. The article presents elaboration of the calculation method for determining the operation modes of the electron beam technology for depositing the metal of wire made of Grade AISI 316L corrosion-resistant austenitic steel on a substrate made of the same material. The calculation method correlates the main process parameters, including the electronic beam current, the additive wire feed rate, and the electron beam gun translation speed, and the effects these parameters have on the geometry, microstructure, and mechanical properties of the obtained beads. The method assumes that the electron beam power is spent for heating and melting the wire and the substrate material. The production process thermal efficiency factor was introduced for taking into account the thermal losses. The item’s macrostructure was analyzed, as a result of which the thermal efficiency was estimated together with the effect the main process parameters have on its value. It was noted in an analysis of the weld beads’ microstructure that columnar crystals (dendrites) appear in the course of metal solidification. It has been found that the electron beam gun displacement speed (the deposition rate), a parameter affecting the molten metal cooling rate, is the key factor influencing the size of columnar grains. The hardness of the obtained beads was investigated, and the following conclusions have been drawn from those investigations. The deposited metal hardness decreases with increasing the bead height. The hardness of beads increases with the deposition rate, which is attributed to a higher melt crystallization rate and the formation of a more fine-grained structure. The growth of hardness toward the bead root is attributed to the fact that the temperature gradient in the root zone is higher than that at the bead top. It has also been found that the hardness value depends on the heat source parameters, the heat source traveling speed (the deposition rate), and the thermophysical properties of the material.

Energy Efficiency Improvement Adding Various Amounts of CNG in the Naturally Aspirated Compression Ignition Engine

The work is devoted to improve energy efficiency and environmental indicators of compression-ignition indirect injection (IDI) engines of transport means and small scale energy sectors, by decreasing dependence on conventional diesel oil by adding compressed natural gas (CNG) in dual fuel mode. It was found that the addition of CNG affects positively on combustion process thermal efficiency and negatively influence on incomplete combustion products such as hydrocarbons (HC) which in average increases from 0ppm to 320ppm. Carbon monoxide (CO) in average increase by about 70% on high and about 90% on medium and low loads comparing with diesel fuel mode. Carbon dioxide (CO2) emissions decrease in average 7%. The nitrogen oxides (NOx) emissions results are controversial, because in higher load modes with dual fuel mode it increased comparing with diesel fuel mode but during low and medium load it decreases sufficiently. Energy efficiency in dual fuel mode during all loads determined higher in high load with all dual fuel mixtures comparing with pure diesel combustion mode, but in medium and low loads because of 25% decrease in excess air ratio the brake specific fuel consumption (BSFC) increases from 7–15% comparing with diesel fuel. The aim of the research is to improve fuel economy and reduce conventional diesel consumption of old low power diesel engine by adding a compressed natural gas in to the combustion process.

Fluidised bed drying of powdered materials: Effects of operating conditions

The fluidized bed drying of powdered materials was studied with a focus on the modifications of the agglomerate population as a result of abrasion and fragmentation. A number of test were carried out in a Lexan® lab-scale fluidised bed with different granular materials, namely a pharmaceutical powder supplied by Novartis-Farma S.p.A., wheat bran, and a molecular sieve 13X, selected to effectively surrogate powders of interest in various industrial applications such as pharmaceuticals pills and adsorption pellets manufacture. The process was monitored to correlate the temperature and the flow rate of the fluidising gas, the temperature and the moisture level in the bed, the qualitative fluidisation patterns. Experimental results were further worked out to highlight the effects of inlet air temperature and gas velocity on process thermal efficiency. Bed material was characterized to assess the modifications of the population of agglomerates as a function of the operating conditions.