Pilot Plant Scale Research Articles

CONVERSION OF WASTE POLYPROPILENE (PP) USING THE ZEOLITE Ni/ZSM-5 TO LIQUID FUEL

The aim of this study was to determine the quality and application of liquid oil produced by pyrolysis catalytic cracking assisted Ni/ZSM-5 from polypropylene (PP) plastic waste using a pilot plant scale pyrolysis reactor. The product of pyrolysis in the form of crude oil is refinery by a distillation bubble cap plate column which consists of 4 trays that are integrated with pyrolysis to minimize energy. The pyrolysis process is performed in a fixed-bed reactor. Plastic waste (250 g PP) and Ni/ZSM-5 catalyst (25 g) are mixed in a reactor at various temperatures of 350, 370, 390, 410, and 430ºC, heated in the reactor with a heating rate 5,3 ºC/minute to produce vapor which will be distilled, and produce the product liquid, gas, and char. The optimal yield of fuel oil at 390ºC is 239 ml of fuel oil/250 g of PP with a conversion of 79.20 %,wt (72%, liquid and 7.20% gas) the rest is char. The characteristics of the fuel oil products obtained are included in the range of gasoline and kerosene-type fuels, with an average yield value of ºAPI in the range of 51-42 for kerosene-type fuel in trays 1 and 2, and for gasoline-type fuel. has an average ºAPI value in the range of 52-63 in trays 3 and 4.

Scalable and sustainable manufacturing of ultrathin metal–organic framework nanosheets (MONs) for solar cell applications

Metal-organic framework nanosheets (MONs) are an emerging class of 2D materials whose tunable chemistry make them ideal for a wide range of sensing, catalytic, electronics and separation applications. However, creating scalable routes to the synthesis of high quality, ultrathin nanosheets remains challenging and little consideration has been given to the economics of making these materials. Here, we demonstrate a scalable synthesis of zinc-porphyrin based nanosheets, Zn2(H2TCPP), for use in organic solar cells and conduct a techno-economic analysis of their pilot-plant scale manufacture. A thorough investigation of the process chemistry of the solvothermal synthesis enabled reduction of reaction time, increased solid content and scale-up of the reaction in batch. Significantly, the addition of triethylamine accelerated the reaction kinetics, which enabled the synthesis temperature to be dropped from > 80 °C to room temperature. Application of these new reaction conditions in a continuous stirred-tank reactor directly formed monolayer MONs at 99 % yield with a space–time yield of 16 kg m−3 day−1, an approximately 20-fold increase in yield compared to adapting the literature procedure. Techno-economic analysis showed a 94 % reduction in the production costs compared to the literature reaction conditions and indicated that the production cost was dominated by ligand price. The general applicability of the method was demonstrated through synthesis of related Cu2(H2TCPP) MONs and tunability through metalation of the porphyrin units with six different metal ions. Finally, the value of the nanosheets was demonstrated through a near doubling in the power conversion efficiency of organic photovoltaic devices when the MONs were incorporated into the active layer. Overall, this work demonstrates the first scalable and sustainable route to producing monolayer nanosheets for high value applications.

Study of start-up of a continuous digester on a laboratory scale treating the sludge issued from wastewater treatment plant in Adrar city (south west of Algeria)

A continuous digester type was designed at the laboratory scale with an aim to studying and improving anaerobic digestion of organic wastes. The results obtained can be extrapolated at large scale pilot plant. To study the digester start-up we have chosen as a substrate the sludge issued from the wastewater treatment plant located in Adrar city (south west of Algeria). Different parameters have been considered such as pH, VFA, COD, and volume of biogas generated during the digestion process.

Magnetic ion exchange resin for reducing disinfection byproducts in drinking water: Pilot-scale study and organic matter characterization

Disinfection is an essential step in drinking water treatment to prevent waterborne illnesses. However, reaction of disinfectants with organic matter in the water can produce carcinogenic disinfection byproducts (DBPs), including trihalomethanes (THMs) and haloacetic acids (HAAs). Magnetic ion exchange (MIEX) resin has been used as a pretreatment to remove organics and reduce DBPs. In this study, a pilot-scale water treatment plant in Birmingham, AL (USA) that employed MIEX as a pretreatment to the conventional pilot treatment train was compared against an adjacent full-scale train that did not use MIEX. THM and HAA formation was tested via simulated distribution system (SDS) testing, and changes in organic character were assessed using fluorescence spectroscopy. MIEX treatment provided 20 % and 25 % removal of THMs and HAAs, respectively, compared to the full-scale treatment under typical SDS conditions. With higher residence times and incubation temperatures (15 days at 35 °C), MIEX treatment reduced HAAs by 36 %. Parallel factor (PARAFAC) analysis revealed that MIEX treatment reduced loadings for a terrestrial humic-like component. Additionally, MIEX treatment resulted in secondary benefits, including a reduction in the coagulant feed rate and a more stable pH and chlorine residual in the MIEX-treated water compared to full-scale treatment.

Production of chickpea protein hydrolysate at laboratory and pilot plant scales: Optimization using principal component analysis based on antioxidant activities

Chickpeas are a nutrient-rich source with optimal and high essential amino acid score. To evaluate its potential as a functional food ingredient, 36 chickpea protein hydrolysates were produced at the lab-scale using food-grade enzymes. Parameters including yields, protein content, hydrolysis degree, and antioxidant activities were employed to identify the most favourable conditions for scaling up production to a pilot plant level using a principal component analysis. The selected hydrolysate demonstrated commendable traits: a substantial content of essential amino acids and proteins at 67.71%, notable protein (73.12%) and weight (72.00%) yields, coupled with exceptional solubility exceeding 80%, and a noteworthy digestibility of 89.50%. Upon transition to pilot plant proportions, the hydrolysate retained its attenuated protein profile while exhibiting heightened antioxidant activities. Derived chickpea protein hydrolysates offer promise for innovative foods applications, impacting health and chronic disease prevention.

Gate-to-gate life cycle analysis of a pilot-scale solar driven two-step thermochemical hydrogen sulfide decomposition for hydrogen production

Hydrogen is one of the most viable options towards decarbonization. It is crucial to upscale the hydrogen economy considering the current state of the environment due to the adverse effects of climate change. In this study, a gate-to-gate Life cycle assessment (LCA) was conducted on a hydrogen sulfide splitting model that replicates a pilot-scale plant by integrating the two-step solar thermochemical H2S decomposition using SimaPro version 9.4.0 software. This analysis starts from the treatment of H2S gas released by the refineries as waste and ends at the production and storage stage of hydrogen. There are two functional units used in this study which are ‘1 kg of H2’ to assess the operational phase of the simulation plant and ‘1 unit of H2S splitting plant’ to determine the environmental performance of the construction of the plant. The top three most impacted midpoint level categories in the operational phase are human carcinogenic toxicity (HTP), freshwater ecotoxicity and marine ecotoxicity with an amount of 3.66 × 10−4, 1.10 × 10−4, and 1.40 × 10−4 kg 1,4-DCB respectively. Electricity has a higher relative contribution to this technology due to the high amount of steel used during the construction of solar tower. Meanwhile, treating H2S leaves a positive impact towards every midpoint indicator, mainly on terrestrial acidification, fine particulate matter formation and ionizing radiation. The H2S splitting technology was set as the baseline to compare with various other H2 production technologies. Scenario analysis was assessed by setting the solar-powered electricity as the baseline and was compared with electricity from different sources such as wind, nuclear and the United Arab Emirates (UAE) grid for the H2S splitting plant. Moreover, uncertainty analysis using Monte Carlo simulation suggests that the probability of gaining results of HTP is the highest between 3.62 × 10−4 to 1.34 × 10−3 kg 1,4-DCB. It can be concluded that electricity powered by renewable sources significantly reduces the environmental burden from the scenario analysis conducted.

Activated Carbon and P-Rich Fertilizer Production from Industrial Sludge by Application of an Integrated Thermo-Chemical Treatment

The cost and environmental impact of sludge disposal methods highlight the necessity of new solutions for resource recovery. This study aims at concurrently producing activated carbon while recovering phosphorous by applying an integrated thermo-chemical treatment to a sludge of industrial origin. The sludge was first subjected to slow pyrolysis on a laboratory scale at different temperatures, and the produced chars were processed by leaching to obtain biocoal. Leaching tests enabled us to define the optimal slow pyrolysis temperatures to maximize leaching performances. Then, sludge was processed in a slow pyrolysis pilot-scale plant, and the produced char was subjected to acid leaching and finally to physical activation. Chemical precipitation was then applied to the liquid leachate to recover phosphorous as a salt. Laboratory-scale slow pyrolysis and leaching tests showed that a higher pyrolysis temperature leads to a lower degree of demineralization by leaching. Leaching enabled us to reduce the char ash content by almost 88%, extracting 100% P, Mg, Ca, and Fe and almost 90% Al. Physical activation of biocoal with CO2 at 700 and 800 °C produced materials with a surface area of 353 and 417 m2 g−1, respectively, that make them potentially applicable as adsorbents in wastewater treatment or in industrial emissions processes. Moreover, the activated carbons showed the atomic H/C and O/C ratios of anthracite, which opens a wide range of alternative market applications to fossil coal, such as metallurgy and the advanced material sector. In addition, the high P and K concentrations in the salt obtained by precipitation make it a promising fertilizing product in line with the current regulations.

Low-Temperature Vacuum Evaporation of Ammonia from Pig Slurry at Laboratory and Pilot-Plant Scale

Livestock manure has a high ammonium content that can limit its direct application on soil as a fertiliser in nitrate-vulnerable zones. Treatment technologies that are able to extract ammonium from livestock manure allow it to be concentrated in small volumes, making it cheaper and easier to transport and use as fertiliser in crop areas where there is a deficit of nitrogen. This study proposed using low-temperature vacuum evaporation to treat pig slurry in order to obtain marketable products that can be used as fertilisers and help close the nitrogen cycle. Two different configurations and scales were used. The first was a seven-litre laboratory-scale evaporator complemented with a condenser, a condensate trapper, an acid trap and a vacuum pump operated at −90 kPa vacuum pressure and at three different temperatures: 50.1 ± 0.2 °C, 46.0 ± 0.1 °C and 45.3 ± 1.3 °C. The second, Ammoneva, is an on-farm pilot-scale evaporator (6.4 m3), capable of working in four-hour batches of 1 t of liquid fraction of pig slurry with an operating temperature of 40–45 °C and −80 kPa vacuum pressure. The laboratory-scale evaporator, which features several novel improvements focused on increasing ammonia recovery, showed a higher nitrogen removal efficiency from the liquid fraction of pig slurry than the on-farm pilot plant, achieving 84% at 50.1 °C operation, and recovering most of it in ammonia solution (up to 77% of the initial nitrogen), with 7% of the ammonia not recovered. The Ammoneva pilot plant achieved a treated liquid fraction with 41% of initial nitrogen on average, recovering 15% in the ammonia solution in the acid trap; so, the NH3 gas absorption step needs to be further optimised. However, due to the simplicity of the Ammoneva pilot plant, which is easily placed inside a 20-foot container, and the complete automation of the process, it is suitable as an on-farm treatment for decentralised pig slurry management. The implementation of the novel design developed at laboratory-scale could help further increase recovery efficiencies at the pilot-plant scale.

Assessment of solar water disinfection enhancement with H2O2 and dissolved oxygen on inactivating different waterborne pathogens

Water scarcity has been growing for the last decades and one feasible solution for water-deprived areas is the storage and treatment of roof-harvested rainwater. Solar disinfection (SODIS) is a proven water treatment procedure, but several drawbacks still need assessing, such as increasing the output volume of treated water, reducing the treatment time and/or increasing the inactivation efficiency performance. In this study, the addition of low concentrations (1–5 mg/L) of H2O2 and/or the increment of dissolved oxygen (DO) has been tested at a pilot plant scale using a solar Compound Parabolic Collector photo-reactor with the aim of enhancing the disinfection efficiency of SODIS. Their performance has been assessed against a consortium of five pathogens normally found in rainwater: E. coli, E. faecalis, S. enteritidis, P. aeruginosa and MS2 bacteriophage. The addition of DO and/or H2O2 to solar photo-inactivation (SP-I) proved to enhance pathogens’ inactivation kinetics. Results have shown that O2 supply affects E. coli, P, aeruginosa and E. faecalis as their kinetic constants increase 1.48, 1.17 and 1.6 times, respectively. On the other hand, H2O2 addition enhances the inactivation of all pathogens. being the most noteworthy MS2 inactivation as > 5 Log Reduction Values (LRV) were reduced for all concentrations between 99% and 95% of the energy required for SP-I. Finally, the combination of both agents is also effective but can only be noted in E. faecalis inactivation, which is better than with only H2O2 addition. The findings obtained in this study show that from the perspective of implementing solar technologies in the field, the addition of DO sparging can be discarded due to a slightly enhanced disinfection performance, while the use of low H2O2 concentrations can be envisaged due to both, the enhancement of the disinfection performance and the competitive cost estimated (0.0025 €/L) in comparison with only SODIS (0.002 €/L).

Assessment of phenol-formaldehyde adhesive distribution on the strand surface by light microscopy

This study reports on a new approach for the detection of phenol-formaldehyde (PF) resin distribution on the strands surface after air-spray application in a glue drum using reflecting light microscopy (LM). The method allows visualization and quantification of PF adhesive distribution on wood strands by using either waterproof paper or 200 µm thick microtomed kiri (Paulownia tomentosa) veneer slices, which were clipped with staples on conventional strands typically used for the production of oriented strand boards (OSB). These strands were mixed with other conventional OSB strands and two types of molecular weight PF prepolymers were sprayed on the strand mixture. While the total area of adhesive coverage was similar for both adhesives, the low molecular weight (LMW) PF prepolymer formed a higher number of adhesive droplets than the high molecular weight (HMW) PF prepolymer. The study offers a new, easy applicable approach for a qualitative investigation of adhesive distribution on the strand surface during gluing on a laboratory and pilot plant scale.

Comparison of the impact of UV-light emitting diode and UV lamp at pilot-plant scale level on quality parameters and consumer perception of fresh chicken meat

The present study compared the impact of two UV light devices: conventional UV lamp and UV-LED on the colour, pH, lipid and protein oxidation of fresh chicken breast meat aerobically stored at 4 °C for 10 days. Lipid oxidation was the most impacted quality attribute in UV lamp treated meat, unlike UV-LED that showed no effect compared to non-treated meat. Slight changes were observed in colour, pH and protein oxidation of chicken samples subjected to UV lamp and UV-LED. To evaluate these changes from a consumer perspective, the different treatment samples were stored at 4 °C for 3 days and colour likeness, odour likeness and overall appearance were assessed by consumer sensory analysis. However, alterations in quality parameters of chicken meat caused by UV light did not decrease overall acceptance in the sensory analysis. UV-LED was the preferred chicken meat by the participants, even compared to non-treated meat.

Increasing Performance of Spiral-Wound Modules (SWMs) by Improving Stability against Axial Pressure Drop and Utilising Pulsed Flow.

Spacer-induced flow shadows and limited mechanical stability due to module construction and geometry are the main obstacles to improving the filtration performance and cleanability of microfiltration spiral-wound membranes (SWMs), applied to milk protein fractionation in this study. The goal of this study was first to improve filtration performance and cleanability by utilising pulsed flow in a modified pilot-scale filtration plant. The second goal was to enhance membrane stability against module deformation by flow-induced friction in the axial direction ("membrane telescoping"). This was accomplished by stabilising membrane layers, including spacers, at the membrane inlet by glue connections. Pulsed flow characteristics similar to those reported in previous lab-scale studies could be achieved by establishing an on/off bypass around the membrane module, thus enabling a high-frequency flow variation. Pulsed flow significantly increased filtration performance (target protein mass flow into the permeate increased by 26%) and cleaning success (protein removal increased by 28%). Furthermore, adding feed-side glue connections increased the mechanical membrane stability in terms of allowed volume throughput by ≥100% compared to unmodified modules, thus allowing operation with higher axial pressure drops, flow velocities and pulsation amplitudes.

Influence of carbon-coated zero-valent iron-based nanoparticle concentration on continuous photosynthetic biogas upgrading

This study assessed the influence of carbon-coated zero-valent nanoparticle concentration (70, 140 and 280 mg L−1) on the performance of photosynthetic biogas upgrading in an indoor pilot scale plant composed of an algal-bacterial photobioreactor interconnected to an external biogas absorption column. In addition, the influence of nanoparticle concentration on the abiotic CO2 gas-liquid mass transfer in the biogas absorption column was also evaluated. Microalgae productivity was enhanced by > 100 % when nanoparticles were added to the cultivation broth, which also boosted nitrogen and phosphorus assimilation from centrate. The biomethane produced complied with most international standards only when nanoparticles were supplemented, achieving CO2 concentrations < 1 % (CO2 removal efficiencies > 98 %) and CH4 concentrations > 94 % in the treated biogas. Finally, this research consistently demonstrated that the improvement of biogas upgrading performance by the addition of nanoparticles was based on a photosynthesis enhancement or stimulation (which significantly increased the pH in the algal cultivation broth) rather than on an improved nanoparticle-mediated CO2 capture in the biogas absorption column.

Validation of the silicon nanoparticle production on the pilot plant scale via long-term gas-phase synthesis using a microwave plasma reactor

The formation of crystalline silicon nanoparticles by homogeneous gas-phase reactions as a direct way to produce high-purity raw material is applied. For this purpose, a microwave-assisted plasma reactor is used. Goal of this paper is to show the scalability of our process technology from laboratory scale to pilot plant scale while maintaining the particle characteristics. This is demonstrated by producing and analyzing silicon nanoparticles during long-term synthesis in a pilot-scale microwave plasma reactor over a period of six hours. The focus is on a high production rate in conjunction with consistent particle characteristics. A continuous production of the mostly spherical crystalline silicon particles with a count median diameter (CMD) of 23.4 nm and a geometric standard deviation of 1.5 is shown using TEM analysis. The stability of the synthesis process is monitored by means of regular sampling and analyzing batch samples extracted from the process every 30 min. Here it is shown that the CMD varies statistically between 21 and 26 nm. Moreover, the decomposition rate of the precursor was determined to be 99%, while the energy supply remained constant. A constant production rate of about 200 g∙h−1 is shown.

A transient mechanistic two-fluid model for Direct Contact Condensation

Intensified heat treatment, using Direct Contact Condensation (DCC), is applied in the production of dairy products to ensure a high level of food safety. The key challenge with DCC is the protein reactions and fouling that limit operational efficiency and sustainability. The use of validated, transient models to predict temperature, phase fraction and velocity gradients is essential and can improve the operation of DCC. Pilot plant scale experiments were performed for a wide range of steam mass fluxes, inlet water temperatures, water Reynolds number and channel pressures to validate a transient 1D two-fluid model. The model was tested against steady-state experimental data and showed good agreement. In addition the model was tested against transient data in which either the water flow rate was step wise decreased or the pressure was adjusted throughout the experiment. In general the model followed the experimental trend well provided that the flow inside the channel is homogeneous.

Effect of concentration and flow rate of electrolyte on electrochemical regeneration of activated carbon at pilot-plant scale

Few research has investigated the problem of regeneration of activated carbon once it has been saturated by organic and inorganic contaminants. Among the regeneration methods, electrochemical technology is one of the most advanced, demonstrating its effectiveness in pilot-plant scale experiments using samples obtained from drinking water treatment plants. In the present study, the optimization of a parallel plate electrochemical reactor with a capacity of 15 kg of activated carbon, has been achieved regarding the electrolyte concentration and flow rate. A regeneration efficiency of approximately 90% was achieved with a 0.25 M H2SO4 concentration, while lower concentrations resulted in a voltage exceeding the acceptable limits for this type of installation. In addition, higher flow rates imply a higher recovery of the porous texture of the regenerated activated carbon. This is, to the best of our knowledge, the first report where these two experimental variables are optimized in a pilot-scale process with real saturated activated carbon samples with different types of pollutants adsorbed in the activated carbon.

A novel intensified approach for treating produced water from oil extraction using a multi-tube type falling-film distillation column equipped with a biphasic thermosiphon: a promising feasibility study.

This study has the novel aim of experimentally examining the efficiency of a pilot-scale treatment plant, composed of a multi-tube type falling-film distillation column equipped with a biphasic thermosiphon, for treating a real sample of high-salinity produced water (electrical conductivity of 20,700 μS cm-1). It investigates the influence of operational parameters, including feed temperature and steam chamber temperature of the biphasic thermosiphon, on distillate flow rate and reduction of conductivity. All experimental conditions tested achieved a reduction greater than 98% in terms of electrical conductivity. The production of treated water increased with increasing feed temperature; the flow rate increased from 20.8 L h-1 to 28.2 L h-1 as the feed temperature was increased from 80 °C to 90 °C, when the steam chamber temperature was fixed at 119 °C. Within the temperature range of the steam chamber, the specific energy consumption during the treatment process, with respect to the biphasic thermosiphon, remained practically unchanged between 0.58 kWh L-1 and 0.60 kWh L-1, when the feed temperature was 90 °C. The results proved the potential of the falling-film distillation technology assisted by heat pipes to be a promising proposal for removing salinity from produced water from oil extraction operations.

The efficiency of UV light-emitting diodes (UV-LED) in decontaminating Campylobacter and Salmonella and natural microbiota in chicken breast, compared to a UV pilot-plant scale device

This study investigated the combined effect of Ultraviolet (UV) light-emitting diode (LED) technology treatment with refrigerated storage of chicken breast meat over 7 days on Campylobacter jejuni, Salmonella enterica serovar Typhimurium, total viable counts (TVC) and total Enterobacteriaceae counts (TEC). An optimised UV-LED treatment at 280 nm for 6 min decreased inoculated S. Typhimurium and C. jejuni populations by 0.6–0.64 log CFU/g, and TVC and TEC population by 1–1.2 log CFU/g in chicken samples. During a 7-day storage at 4 °C, a 0.73 log reduction in C. jejuni was achieved compared with non-treated samples. Moreover, the UV-LED effectiveness to reduce TVC and TEC during refrigerated storage was compared with a conventional UV lamp and a similar efficiency was observed. The impact of UV-LED and UV lamp devices on the microbial community composition of chicken meat during storage was further examined using 16 S rRNA gene amplicon sequencing. Although similar bacterial reductions were observed for both technologies, the microbial communities were impacted differently. Treatment with the UV conventional lamp increased the proportion of Brochothrix spp. In meat samples, whilst Photobacterium spp. Levels were reduced.

Solar photo-Fenton optimization at neutral pH for microcontaminant removal at pilot plant scale

The increasing occurrence of micropollutants in natural water bodies has medium to long-term effects on both aquatic life and human health. The aim of this study is to optimize the degradation of two pharmaceutical pollutants of emerging concern: amoxicillin and acetaminophen in aqueous solution at laboratory and pilot scale, by solar photo-Fenton process carried out at neutral pH using ethylenediamine-N,N′-disuccinic acid (EDDS) as a complexing agent to maintain iron in solution. The initial concentration of each compound was set at 1 mg/L dissolved in a simulated effluent from a municipal wastewater treatment plant (MWTP). A factorial experimental design and its surface response analysis were used to optimize the operating parameters to achieve the highest initial degradation rate of each target. The evolution of the degradation process was measured by ultra-performance liquid chromatography (UPLC/UV), obtaining elimination rates above 90% for both contaminants. Statistical study showed the optimum concentrations of Fe(III) at 3 mg/L at an Fe-EDDS ratio of 1:2 and 2.75 mg/L H2O2 for the almost complete removal of the target compounds by solar photo-Fenton process. Validation of the experimental design was successfully carried out with actual MWTP effluent spiked with 100 μg/L of amoxicillin and acetaminophen, each at pilot plant scale.

CuO–TiO2 pilot-plant system performance for solar photocatalytic hydrogen production

The main goal of the present study was to explore photocatalytic performance of the TiO2–CuO mixture, for solar to hydrogen conversion at pilot plant scale under two different irradiation conditions (sunny and partly cloudy), focusing on high-temperature pretreatment of the catalyst mixture to try to improve TiO2 doping with copper. P25–TiO2 and commercial CuO were used with different amounts of Cu (2 wt% or 7 wt% Cu) calcined at 200–400 °C during several hours. Catalysts were tested at pilot plant scale using solar compound parabolic collectors, with glycerol as the sacrificial agent. The photocatalyst prepared after heating at 200 °C for 3 h and with 7 wt% Cu, resulted in higher hydrogen production than under the other heating conditions, and results were slightly better (5–10%) than the reference values with the untreated catalysts. Photocatalytic efficiency was slightly lower at the higher calcination temperature (400 °C). CO2 production and formation of formate and glycolate clearly demonstrated glycerol photoreforming. The Cu from the calcined catalyst remaining on the solid was significantly less (2.5%) than on the non-calcined catalyst (4.2%), with an important fraction of lixiviated copper and copper deposition on the reactor walls. This is a critical drawback that must be considered for large-scale applications.