Dry Type Research Articles

Simulation of Ozone Distribution in an Innovative Drying and Sanitising Cabinet Chamber

Common designs of workwear drying units require not only energy efficiency but also effective disinfection. One possibility of sanitising clothes during drying is to use the ozone generated inside the drying chamber. This process requires precise management of airflow and a uniform distribution of ozone in the chamber. Therefore, optimising the shape of the drying chamber must include not only the correct flow of drying air but also the correct distribution of ozone. This paper addresses the difficult problem of modelling the flow of sanitising ozone in an innovative drying chamber. The innovative shape of the chamber is shown in this article. Due to the low percentage of ozone in the air (up to 10 ppm), CFD simulation models of the usual mixture type are too inaccurate; therefore, special models have to be used. Therefore, this paper presents an experimentally verified methodology to simulate ozone flow in an innovative drying and sanitising cabinet using two methods: Discrete Phase Model (DPM) and Species Transport (ST). The DPM method uses a Euler–Lagrange approach to qualitatively assess the spread of ozone particles, treated with a description of the movement of the particles and not as a continuous gaseous substance. On the other hand, this already allows the verification of ozone concentrations, with an appropriate conversion of the measured quantities. The ANSYS/FLUENT 2023R1 program was used for the simulations after careful selection of the mesh, closing models, boundary conditions, etc. Simulations made it possible to analyse the distribution of ozone in the workspace and assess the effectiveness of the sanitisation process. The results of the simulations were verified on the basis of empirical tests, which showed the correctness of the model and the correct distribution of the sanitising ozone in the entire volume of the drying chamber in the innovative drying–sanitising chamber. The complete simulation of the air and ozone distribution using the presented models allowed for the optimisation of the opening and shapes, which contributed to improving the energy efficiency of the unit and increasing the efficiency of the sanitisation processes, making the described methodology very effective for optimising the chambers of various types of dryers.

Identification of novel sub-phenotypes of severe ARDS requiring ECMO using latent class analysis

BackgroundSub-phenotyping of acute respiratory distress syndrome (ARDS) could be useful for evaluating the severity of ARDS or predicting its responsiveness to given therapeutic strategies, but no studies have yet investigated the heterogeneity of patients with severe ARDS requiring veno-venous extracorporeal membrane oxygenation (V-V ECMO).MethodsWe conducted this retrospective multicenter observational study in adult patients with severe ARDS treated by V-V ECMO. We performed latent class analysis (LCA) for identifying sub-phenotypes of severe ARDS based on the radiological and clinical findings at the start of ECMO support. Multivariate Cox regression analysis was conducted to investigate the differences in mortality and association between the PEEP setting of ≥ 10 cmH2O and mortality by the sub-phenotypes.ResultsWe identified three sub-phenotypes from analysis of the data of a total of 544 patients with severe ARDS treated by V-V ECMO, as follows: Dry type (n = 185; 34%); Wet type (n = 169; 31%); and Fibrotic type (n = 190; 35%). The 90-days in-hospital mortality risk was higher in the patients with the Fibrotic type than in those with the Dry type (adjusted hazard ratio [95% confidence interval] 1.75 [1.10–2.79], p = 0.019) or the Wet type (1.50 [1.02–2.23], p = 0.042). The PEEP setting of ≥ 10 cmH2O during the first 3 days of ECMO decreased the 90-days in-hospital mortality risk only in patients with the Wet type, and not in those with the Dry or Fibrotic type. A significant interaction effect was observed between the Wet type and the PEEP setting of ≥ 10 cmH2O in relation to the 90-day in-hospital mortality (pinteraction = 0.036).ConclusionsThe three sub-phenotypes showed different mortality rates and different relationships between higher PEEP settings in the early phase of V-V ECMO and patient outcomes. Our data suggest that we may need to change our management approach to patients with severe ARDS during V-V ECMO according to their clinical sub-phenotype.

Design and assessment of an adapted absorber solar air collector tailored for sustainable drying applications

The design of a relevant solar air collector (SAC) is imperative to make the drying industries self-reliant and sustainable in terms of energy. However, the literature doesn’t describe the coherent design assessment of SAC, and its viability for a drying system provided the scale-up opportunity for commercial applications. Hence, the present work was devoted to estimating the heat load for a particular drying condition, a methodological understanding of SAC design, and an investigation of the performance of the newly developed solar collector. The essential design criteria were the moisture content of fresh and intended dried items, physical attributes of items, dryer capacity, preferred drying temperature, projected drying duration, required air speed (based on dryer type), and local climate (solar radiation, ambient temperature and relative humidity). The regular semi-hexagonal shape aluminium (Al) sheet was chosen to introduce air turbulence while maximizing the surface area available for heat transfer. The regular semi-hexagonal absorber was outfitted with helical springs to generate air turbulence and augment heat transfer. A double glazing (polycarbonate) of 5 mm apart was mounted to impede radiation heat loss. Three successive days of the experimental study showed that the average temperature increases of air passing through SAC were 36.02 °C, 37 °C, and 39.2 °C. The optimal tilt angle with the horizontal surface was found to be 35° in a south-facing direction for the month of January. The highest energy efficiency was found to be 40.5 %, while the lowest was found to be 24.73 %. The sustainability index of the SAC was found to be 1.02. The experimental results clearly demonstrate that the designed SAC was capable of supplying adequate heat energy (at the minimum of 155.86 W/hr.) to meet the necessary heat load (125.82 W/hr.) for agro-products drying at the designed capacity.

Comparative S/TEM study of superconducting Ta quantum resonators by wet and dry etching types

Superconducting resonators play a pivotal role in various quantum technology applications, such as quantum computing and high-frequency communication systems. The performance of these resonators is closely tied to the properties of the superconducting films used in their fabrication. In this study, we investigated the impact of wet and dry etching on tantalum (Ta) films leveraging advanced scanning transmission electron microscopy-based characterization methods and examined the morphological, chemical, and strain changes caused by the etching processes. Consequently, we report the significant differences between the two etching methods, with dry etching resulting in straight slanted sidewalls and a thinner oxidized layer, while wet etching produced curved sidewalls and undercuts. Both methods led to the formation of a residual Ta wedge at the lower part of the sidewall, causing lattice deformation, which could adversely influence the homogeneous operations of superconducting devices. These insights enhance our understanding of how etching influences superconducting films, offering valuable guidance for optimizing resonators and related devices. Our findings mark a significant stride in advancing quantum technologies and high-frequency communication by enhancing our practical understanding of superconducting material fabrication.

Analysis of Corn Drying Rack Position on Tray Type Dryer on Drying Rate

This research aims to determine the drying characteristics of corn kernels using a tray-type dryer, including the moisture content of the corn kernels over time, the mass of the tested corn kernels over time and the drying rate over time. This research uses the experimental method. The drying process uses an incoming drying hot air temperature of 65ºC with an incoming hot drying air speed of 2 m/s, repeated three times until a water content of 14 ± 0.5% is reached. The dryer in this study used four stacking shelves counting from the bottom, which were filled with 500 grams per shelf. This research shows that the further the shelf is positioned from the incoming hot drying air, the lower the drying rate. Vice versa, the closer the drying Shelf is to the incoming hot air, the greater the drying rate. The average decrease in corn kernel mass was 0.95% for shelf 1, 0.93% for shelf 2, 0.90% for shelf 3 and 0.88% for shelf 4 during a drying period of 3.5 hours. The average decrease in water content was 4.4% for shelf 1, 4.29% for shelf 2, 4.15% for shelf 3 and 4% for shelf 4 during a drying period of 3.5 hours. The further the position of the shelf from the hot air dryer, the less air content contained in the material on the shelf can be absorbed by the hot air dryer and vice versa. The average drying rate was 16.8% for shelf 1, 15% for shelf 2, 13.6% for shelf 3 and 12.8% for shelf 4 during a drying period of 3.5 hours at a drying hot air temperature of 65oC with a drying air speed of 2 m/s. The research data analysis results showed that the hot air dryer should not be passed from below but rather from the side. This affects the drying process in the dryer and makes it evener.

Nutrient Digestive Bypass: Determinants and Associations with Stool Quality in Cats and Dogs

The effect of digestive bypass macronutrients and age on stool quality (moisture and firmness) in dogs and cats is not well understood. Data were analyzed from digestibility tests (n = 2020, 361 dogs and 536 cats) including dry and wet product types. Both food and feces were measured for moisture and nutrients according to standard protocols; stool firmness was graded. Linear mixed modeling was used to evaluate the associations between nutrient bypass, age and stool quality. Bypass protein increased stool moisture (dog, cat p < 0.0001) and decreased firmness (dog p = 0.01, cat p < 0.0001), while bypass fiber decreased stool moisture and increased firmness (dog, cat p < 0.0001 for both). Both species manifested a negative quadratic effect of advanced age on stool firmness (dog p < 0.0001 and cat p = 0.02). However, the association of advanced age (quadratic effect) with metabolizable energy required to maintain body weight was different between species; dogs had a positive association (p = 0.028), while it was negative for cats (p < 0.0001). Taken together, these data may aid in the development of food formulations for companion animals, which can better meet changing nutritional needs across life stages.

Utilization of PID Controller to Optimize Energy Consumption in Hybrid Forced Convection Dryer

The drying process is essential in food processing, particularly for grains or beans. This process can influence the characteristics and quality of the dried material. However, the drying process needs massive energy. This condition can increase the cost of production. Therefore, optimizing energy is needed during the drying process. PID controller was proposed to be utilized in the dryer to maximize energy efficiency in this study. This method was implemented in forced convection and hybrid forced convection dryer. The temperature sensor was used as parameter control of the PID method to control the electric heater and exhaust fan. Moreover, PZEM-004T was used to measure the energy consumption. The objective of this study is to implement and fine-tune the PID controller to obtain the performance difference between two types of dryers, namely forced convection and hybrid forced convection. This will be achieved by collecting data on power and energy consumption. The results indicate that the hybrid dryer can significantly decrease power and energy consumption by 48.32% and 49.18%, respectively, compared to the forced convection dryer.

Peningkatan teknologi bagi agroindustri pliek-u sebagai upaya pelestarian kearifan lokal di Aceh [Technology improvement on pliek-u agroindustry as an effort to maintain a local wisdom in Aceh

Pliek-u is a specialty food product in Aceh with local wisdom values that should be preserved. The Program of Community Service Based Product (PKMBP) aimed to improve the pliek-u agro-industry by adapting simple processing technologies so that it could lighten work, produce quality products, and attract the interest of the younger generation as pliek-u entrepreneurs in future. The method applied consist of surveys, preparation of tools and materials, assembly of a solar tunnel dryer type Hohenheim Aceh and a hydraulic press, training and dissemination of technology through field schools, and evaluation of the program with pre-tests and post-tests. Data analysis was carried out using the Wilcoxon rank test with alpha of 5%. The results of the program were the construction of 1 unit of Hohenheim Aceh tunnel dryer, 1 unit of hydraulic press, and the implementation of training and dissemination activities which have been published in the form of videos on YouTube media and press releases through online media. The results of the Wilcoxon rank test also showed that of the 13 participants whose data were valid, 100% of participants received positive rankings and the pre-test scores were significantly different from the post-test scores. Thus, it can be concluded that the program carried out has contributed to increasing the knowledge, expertise capacity, and interest of participants in pliek-u processing technologies since the profile of conventional agroindustry can be transformed to be better agroindustry by the use of solar tunnel dryer type Hohenheim Aceh and hydraulic press. In addition, the use of technologies will ensure the halal requirement of pliek-u.

Transformation of dry dipterocarp to dry evergreen forests alters food webs of web-building spiders and their prey

Anthropogenic habitat modification is a major contributor to global change. While the modification of natural habitats to agroecosystems attracts most of the attention, little is known about the conversion of one natural ecosystem to another. Dry dipterocarp forest is the key dry forest type across Southeast Asia. Moderate fire disturbance is essential for its regeneration, but humans often prevent fire in these forests. Consequently, dry dipterocarps can change to dry evergreen forests through succession. The consequences of this conversion on food webs are unknown. Using the network approach, we compared the food webs of web-building spiders and their prey in the understory between dry dipterocarp (open canopy, uniform understory) and dry evergreen forests (closed canopy, heterogeneous understory) in north-eastern Thailand. Overall, we collected 560 individual web-building spiders belonging to 37 genera. Further, we collected 1139 prey items from spider webs belonging to 16 arthropod orders. The composition of captured prey and the network structure differed between the forest types. Specifically, the web-building spiders were more specialized and their niches overlapped less in dry dipterocarps than in dry evergreens. The differences in food-web structure were driven mostly by trophic groups turnover rather than interaction rewiring. Implications for insect conservation: The transformation of dry dipterocarp to dry evergreen forests from the prevention of fire disturbance may lead to an altered ecological function of web-building spiders in forest understories. As trophic links and their strength are rewired, habitat modification may also lead to changes in nutrient and energy flow in forest understories.

Abstract C069: Unraveling the complexity of malignant peritoneal mesothelioma: A comprehensive case study of diagnosis, clinical features, and therapeutic challenges in a 75-year-old male

Abstract Introduction: Malignant Peritoneal Mesothelioma (MPM) is a rare and aggressive intra-abdominal neoplasm originating from mesothelial cells. Although asbestos exposure is a known risk factor, MPM's molecular pathogenesis differs from its pleural counterpart. Case Presentation: A 75-year-old male, with a past medical history of recently diagnosed mesothelioma, presented to the emergency department for a two-week progression of abdominal distension, early satiety, and dyspnea aggravated by activity. One year prior, he initiated medical evaluation for fluid retention and abdominal distension. A recent omental biopsy confirmed the diagnosis of mesothelioma, prompting the initiation of chemotherapy every three weeks. Despite paracentesis performed monthly, the patient experienced worsening shortness of breath and early satiety post-chemotherapy. Discussion: Malignant Peritoneal Mesothelioma poses a diagnostic challenge due to the absence of specific signs or symptoms. Common manifestations include abdominal distension, pain, early satiety, weight loss, dyspnea, chest pain, and fatigue. Rare symptoms encompass new-onset hernia, fever of unknown origin, night sweats, or incidental findings during physical examinations or laparoscopy. Delays in presentation and diagnosis contribute to the advanced stage at diagnosis, with most cases having already spread throughout the abdominal cavity. Three distinct presentations of MPM include the Dry Painful Type, characterized by abdominal pain with minimal ascites; the Wet Type, presenting with abdominal distension and ascites; and the Mixed Type, combining abdominal pain and distension. Paraneoplastic phenomena, such as fever, thrombocytosis, malignancy-related thrombosis, hypoglycemia, hypoalbuminemia, paraneoplastic hepatopathy, and rarely, Coombs-positive Hemolytic anemia, further complicate the clinical picture. Surgical gross and microscopic descriptions of liver biopsies indicated chronic hepatitis with mild portal inflammation, grade 1, and no fibrosis, stage 0. Notably, the omental biopsy confirmed Malignant Mesothelioma of the epithelioid type. Immunohistochemical stains supported the diagnosis, revealing positivity for CK AE1/AE3, calretinin, WT1, CK7 (focally), and GATA3 (focally), while testing negative for BAP1, CDX2, chromogranin, CK20, hepatocyte antigen, PAX8, PSA, synaptophysin, and TTF1. Due to the rarity of MPM, no standardized treatment protocols exist. Cytoreductive surgery (CRS) and hyperthermic intraoperative peritoneal perfusion with chemotherapy (HIPEC) are recommended for selected patients without extraperitoneal disease spread, possessing a good performance status and potential for complete surgical cytoreduction. Systemic chemotherapy, particularly pemetrexed-based regimens, is advocated for patients ineligible for CRS/HIPEC. Conclusion: MPM's aggressive nature poses diagnostic and therapeutic challenges. The scarcity of standardized guidelines emphasizes the importance of ongoing research to enhance understanding, improve diagnostics, and develop targeted therapies Citation Format: Aliya M Khan, Mehmet Hepgur, Aryama Sharma. Unraveling the complexity of malignant peritoneal mesothelioma: A comprehensive case study of diagnosis, clinical features, and therapeutic challenges in a 75-year-old male [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C069.

Guiding trust: The role of labeling information in the market for gluten-free pasta (2019–2023)

Labeling transparency is crucial in today's consumer landscape, ensuring informed choices and trust. Food labels are the first piece of information consumers have and become critical when foods must meet dietary restrictions. With its widespread consumption, gluten-free pasta is a fitting model to evaluate labels’ contribution to food literacy. The scope of this study is to examine the clean status and transparency of gluten-free pasta labels in the global marketplace analyzing by ingredient composition, nutritional facts, nutritional claims, and the implementation of quantitative ingredient declarations (QUID). To achieve this, Mintel Global New Product Database (GNPD) was used to retrieve a total of 1188 products sold from 2019 to 2023. Findings revealed variations in gluten-free pasta ingredients, with fresh and dry types varying in nutrients. Branded and private-label pasta differed in salt content, while pulses-based pasta was fiber and protein-rich but pricier. Organic pasta did not consistently show superior qualities, and whole grains did not change nutrition or price. Vegan options were similar in nutrition and price to vegetarian choices. While nutritional claims generally complied with regulations, inconsistent use of QUID highlighted the need for stricter labeling standards to ensure product transparency and support consumer decision-making. Our findings underline the critical role of clear and accurate labeling in empowering consumers and advocating for enhanced regulatory oversight.

Solar Drying Technology for Agricultural Products: A Review

The application of solar drying technology for fruits, vegetables and other crops is one of the most attractive, cost-effective and eco-friendly. Many types of solar dryers have been designed and developed in different parts of the world, having different degrees of technical performance. There are four types of solar dryers: (1) direct solar dryers, (2) indirect solar dryers, (3) mixed-mode dryers and (4) hybrid solar dryers. A synthesis view of the classification of solar energy dryers is also presented. Two groups of solar energy dryers can be identified: Passive or natural-circulation solar energy dryers and active or forced convection solar energy dryers. This paper is a review of all these types of solar dryers, including aspects of the various designs, details of construction and operational principles. Therefore, the selection of dryers for a particular situation is primarily based on what is available and the types of dryers currently used are widely based on available circumstances. Some recent developments in solar drying technology and the appropriateness of each design type for application by farmers in developing countries are also discussed.

A manual operated and eco-friendly plasma-assisted polymerization method for enhancing surface weather resistance of insulation

With the increasing demand for high-voltage long-distance power transmission, insulation as the first protection of power system, faces serious challenges from material degradation caused by moisture invading, surface contamination and pollution flashover. Addressing the issue requires significant effort and may cause harmful by-product emission from large-scale wet type material processing. In this work, a novel eco-friendly dry treatment method based on manual operated Air/Alkoxysilane(PMDMS)/plasma is developed to enhance weather resistance and electrical performances of contaminated insulation. Tiny amounts of harmless reaction medium are transmitted to plasma through controllable air bubbling, and it implements precise dry type processing on material surface. Plasma pulverizes pre-existing contamination and synchronously activates hydrolysis-polymerization of PMDMS to deposit Si-containing protection layer (Si-O2, Si-CH3) on surface. It is demonstrated that the plasma treatment inhibits dirt pollution and electrical erosion of on-site 110 kV silicone rubber (SIR), and the electrical and hydrophobicity properties are both promoted. Flashover voltage increases from 4.65 to 8.71 kV, and water contact angle increases from 138.27° to 146.41°. Overall, this newly-developed dry portable plasma treatment strategy for insulation enhancement avoids environment pollution and economic losses, and provides a scalable avenue for on-site insulation recovery and service life prolonging.

Review Paper on Diffierent Types of Solar Dryer

Abstract: One of the most appealing and economical uses of solar energy is drying agricultural goods. With differing degrees of technical performance, a multitude of solar dryer types have been devised and developed across the globe. In general, solar dryers come in four different varieties: (1) direct solar dryers, (2) indirect solar dryers, (3) mixed-mode dryers, and (4) hybrid solar dryers. The product being dried, as well as technical and financial concerns, are reviewed in this paper together with other solar dryer kinds. Technically speaking, integrated storage, high efficiency, compact collector design, and long-life drying systems are the main focuses in the development of solar-assisted drying systems for vegetables. There exist alternative systems to air-based solar collectors. By using a water-to-air heat exchanger, water-based collectors are another option. A water-to-air heat exchanger can be used to push hot air used for drying agricultural products to pass through it. As part of the solar drying system, the hot water tank stores heat

Microwave-based and convective drying of cabbage (Brassica oleracea L. var capitata L.): Computational intelligence modeling, thermophysical properties, quality and mid-infrared spectrometry

This study assessed and compared the impact of hot air oven drying (HAD) at 50, 60 and 70 °C and microwave drying (MWD) at 195, 307 and 521 W on the kinetics of thermophysical properties and quality of dried cabbage. The thermophysical properties were computed using established model equations. The proximate composition, bioactive compounds, antioxidant capacity (AOC), color and functional groups were analyzed using Association of official analytical chemists (AOAC) test protocol, High performance liquid chromatography (HPLC), Ultraviolet-visible (UV–Vis) spectrometry and Attenuated total reflectance coupled to Fourier transformed infrared spectroscopy (ATR-FTIR), respectively. The moisture ratio was modeled using probabilistic computational intelligence modeling approaches. The results revealed that only density, thermal diffusivity and thermal effusivity appeared to be kinetically controlled by moisture content. Stepwise linear regression (SLR) model and Gaussian process regression (GPR) model were more accurate in simulating the moisture ratio. Increasing HAD temperature preserved all of the proximate compositions except carbohydrates. Similarly, increasing MWD power preserved all the proximate compositions except crude fiber. Increasing HAD temperature from 50 to 60 °C and 60–70 °C decreased the total flavonoid content (TFC) and total phenolic content (TPC) by 21.31 % and 13.60 %, respectively but increased the AOC from 27.2 to 39.6 %. Increasing MWD power levels from 195 to 307 W and 307–521 W decreased TFC by 13.2 % and 0.7 %, respectively but increased the TPC by 9.72 % and 13.14 %, thus AOC increased from 35.2 to 45.7 %. MWD presented higher AOC relative to HAD. Drying at 50 °C and 307 W gave the highest whitening index in HAD and MWD. ATR-FTIR analysis revealed the formation of new compounds by thermal effect. SLR and GPR were more accurate in modeling the drying kinetics. HAD and MWD affected the quality parameters of cabbage differently, thus the choice of the dryer type will depend on the parameters of interest.

Comparative S/TEM Study of Superconducting Ta Quantum Resonators by Wet and Dry Etching Types

Comparative S/TEM Study of Superconducting Ta Quantum Resonators by Wet and Dry Etching Types

Numerical investigation in an indirect concentrated solar thermal dryer incorporated with discrete mirrors

The objective of this study is to promote the production for small scale drying industries by reducing the drying time of agricultural products. Discrete mirrors are arranged in a parabolic fashion and used as reflectors to concentrate the incoming solar radiation. The available solar flux is doubled by using this discrete arrangement of mirrors. Optical simulations are performed using Monte Carlo Ray tracing algorithm and various effects were studied to select the best arrangement of mirrors. The concentrated type dryer has been numerically simulated and no-load testing is performed using ANSYS Fluent. Simulation is carried out for various inlet velocities from 0.1 to 1 m s−1. The concentrated setup operates between 0.4 and 1 m s−1 of velocity to obtain temperature in the range of 40–70 °C. The maximum and minimum increase in outlet temperature is 23.52% and 2.87%, and the Nusselt number enhancement is 18.94% and 4.15%, respectively.

Optimizing the drying process with the surface response method for snap beans, sweet corn, and carrots

Abstract Vegetables contain many nutrients that are susceptible to loss when dried. Pre-treatment is needed to reduce nutrient loss during drying. This research aims to determine optimal pre-treatment and drying conditions for dried vegetables. Optimization using the D-optimal response surface method for snap beans, carrots, and sweet corn. The optimized process conditions are drying temperature (45°C, 50°C, 55°C); blanching technique at 75°C (immersion, steaming); freezing treatment (with freezing -20°C 24 hours, without freezing); and type of dryer (cabinet dryer, dehydrator). The research results show that immersion blanching (75°C), freezing (-20°C, 24 hours), and cabinet dryer type at 50°C are the best conditions for processing dried snap beans. The best method for drying sweet corn is immersion blanching (75°C), freezing (-20°C, 24 hours), and drying in a dehydrator-type drying at 50°C. Immersion blanching (75°C), freezing (-20°C, 24 hours), and dehydrator-type dryer at 55°C are the best methods for drying carrots.

Uji Kinerja Alat Pengering Tipe Batch Dryer untuk Pengeringan Kakao (Theobroma cacao L.) dengan Sistem Penghembus Udara Panas

Cocoa is a superior export commodity for Indonesia. Lampung is one of the largest cocoa producing regions in Indonesia. In processing cocoa beans, drying is the most important factor for quality. The causes of the low quality of cocoa beans include unfermented cocoa beans before drying and the conventional drying process. Drying of cocoa can be done using a bacth type dryer with a hot air blower system with a large enough capacity that has been built on offer. This study aims to examine the performance of batch type cocoa dryers with hot air blowing systems. The method used in this study is an experimental and descriptive method that uses cocoa with different initial moisture content, namely 36.62%, 42.20%, and 32.61%. The results showed that the batch type dryer produced plenum temperature of 590 C, 580 C, 620 C and the temperature of the material that was 500 C, 500 C, and 510 C. The higher the temperature used, the faster the drying time and the lower the initial temperature of cocoa the faster the drying process. Rubber wood fuel used in each test is 101 kg, 123 kg, 95 kg. Drying time for all three tests is 10 hours, 11 hours, and 10 hours. The efficiency of drying using batch type dryer is 26.01%, 26.75%, 25.52%. The weight of 1 kg of rubber wood on average can dry 5 kg of wet cocoa Keywords: Bath Type Dryer, Cocoa, Moisture Content, Temperature.

Experimental testing on the performance of solar dryer equipped with evacuated tube collector, rock bed heat storage and reflectors

Agricultural products can be dried in an open sun; but such drying method has poor quality of the product causes to grow bacteria and microorganisms and long drying time. In order to alleviate those draw backs of open sun drying, direct solar dryers were developed; but this type of dryer reduces the product quality due to direct exposure of solar radiation. Then, an indirect solar dryer became more important and efficient method. However, the most solar dryers were developed with less efficient flat plate solar collectors. A few solar dryers were developed using efficient solar collector called evacuated tube solar collector (ETC) but they have low overall performance. The goal of this research is to create a dependable solar dryer system for drying agricultural products. It was a solar dryer system with an independent rock bed thermal storage unit and an evacuated tube collector having reflectors. In this case, a rock bed has been a well-insulated with thermal insulation and its top surface is covered by a transparent double-glass. This system is intended to dry potato slice that weigh of 7.5 kg sample having a wet base initial moisture level of 80.1 %, until it reaches the ideal moisture content of 7–13 %. The solar dryer has been developed from drying chamber having size of (length x breadth x height) of 85 cm×61 cm x 62 cm, evacuated tube collector area of 1.3 m2, and rock bed volume of 0.137 m3 (with a solar absorber area of 0.52 m2 and a depth of 0.26 m). The solar dryer system was built and tested with loading slices at various air flow rates and open sun. Here, at a 0.016 m3/s air flow rate as compared to lower and higher air flow rates, more moisture reduction (9.3 % within eight hours and 0.664 kg/h), higher efficiency of the solar collector (62.02 %), more heat production from the system (20.79 MJ, of which 4837.8 kJ was recovered from the rock bed), and higher dryer efficiency (23.87 %) were attained. Compared to open-sun drying, 20 % less time was needed for drying. In addition, the study examined the significance of the reflectors and the rock bed. In comparison to the situation of utilizing ETC alone and 30 % of the drying period in relation to the open sun, the introduction of a reflector on the collector increased the average net heat obtained from the collector by 5.1 %. In another instance, the slice's moisture content was lowered to 12.37 % in under eight hours using ETC alone, while the dryer's efficiency was 29.82 %. However, the drying rate rise by 3.7 % in comparison to the dryer equipped with ETC alone because of the enhanced heat output in the dryer, which used ETC with a rock bed's help.