Storage Bins Research Articles

Analysis of abrasion wear in particle storage and valve subsystem for falling particle concentrating solar power

Solar energy capture and storage using falling solid particles are being explored for cost-effective next generation concentrating solar power systems. A critical consideration in this technology is the abrasion wear caused by the sliding of the particles under varying speed and pressure over component surfaces. This study presents computational modeling of a subsystem comprising a particle storage bin discharging through a flow control valve that is prone to abrasive wear. The effects of several geometric parameters are systematically evaluated for their impact on spatial and temporal abrasion rates in the storage bin, the control valve, and the valve housing. The findings provide insights into the locations most susceptible to abrasion, and the use of targeted abrasion mitigation coatings is illustrated.

Solid health care waste management practice in Ethiopia, a convergent mixed method study

IntroductionHealthcare waste is any waste generated by healthcare facilities that is considered potentially hazardous to health. Solid healthcare waste is categorized into infectious and non-infectious wastes. Infectious waste is material suspected of containing pathogens and potentially causing disease. Non-infectious waste includes wastes that have not been in contact with infectious agents, hazardous chemicals, or radioactive substances, similar to household waste, i.e. plastic, papers and leftover foods.This study aimed to investigate solid healthcare waste management practices and develop guidelines to improve solid healthcare waste management practices in Ethiopia. The setting was all health facilities found in Hossaena town.MethodA mixed-method study design was used. For the qualitative phase of this study, eight FGDs were conducted from 4 government health facilities, one FGD from each private health facility (which is 37 in number), and forty-five FGDs were conducted. Four FGDs were executed with cleaners; another four were only health care providers because using homogeneous groups promotes discussion. The remaining 37 FGDs in private health facilities were mixed from health professionals and cleaners because of the number of workers in the private facilities. For the quantitative phase, all health facilities and health facility workers who have direct contact with healthcare waste management practice participated in this study. Both qualitative and quantitative study participants were taken from the health facilities found in Hossaena town.ResultSeventeen (3.1%) health facility workers have hand washing facilities. Three hundred ninety-two (72.6%) of the participants agree on the availability of one or more personal protective equipment (PPE) in the facility ‘‘the reason for the absence of some of the PPEs, like boots and goggles, and the shortage of disposable gloves owes to cost inflation from time to time and sometimes absent from the market’’. The observational finding shows that colour-coded waste bins are available in 23 (9.6%) rooms. 90% of the sharp containers were reusable, and 100% of the waste storage bins were plastic buckets that were easily cleanable. In 40 (97.56%) health facilities, infectious wastes were collected daily from the waste generation areas to the final disposal points. Two hundred seventy-one (50.2%) of the respondents were satisfied or agreed that satisfactory procedures are available in case of an accident. Only 220 (40.8%) respondents were vaccinated for the Hepatitis B virus.ConclusionHand washing facilities, personal protective equipment and preventive vaccinations are not readily available for health workers. Solid waste segregation practices are poor and showed that solid waste management practices (SWMP) are below the acceptable level.

Physicochemical properties in relation to the flow behavior of soybean meal

Abstract Caking of soybean meal during storage and the resultant difficulty in discharging from storage bin is a practical problem in animal feed‐related industries. This study investigated the physicochemical factors related to soybean meal flowability and the effect of anticaking agents. Results showed the soybean meal had a D50 of 389.1 µm and a D90 of 1.098 µm. The equilibrium relative humidity of soybean meal at various ambient temperatures ranged from 57 % to 69 %. Moisture had a major influence on soybean meal flowability and the critical moisture content for loss of free flow capacity was around 17.81 % (wet basis, wb). Soybean meal was characterized as amorphous by X‐ray diffraction analysis, and its glass transition temperature is greatly affected by the moisture content. The addition of silicon dioxide helps keep soybean meal free flowing when stored at a relative humidity of 90 % and a temperature of 45 °C possibly due to its low affinity for moisture. Overall, moisture absorption is perceived as the main factor causing the occurrence of caking of soybean meal.

Apple mycotoxins: From orchard to processed apple puree

Apples and apple-derived products can be contaminated with patulin and, to a lesser extent, aflatoxin B1 and fumonisins. Fruits were collected from Golden Delicious and Imperatore trees in three orchards in Veneto, Northern Italy, and analysed for the presence of fungi and mycotoxins. Sampling and analyses were also carried out from storage bins to final puree tanks along the apple-puree production chain. Alternaria spp. and Penicillium spp. were commonly isolated from apples collected in the field, but their presence varied with cultivar and orchard location. In contrast, Aspergillus section Flavi spp. and Fusarium spp. were only detected via direct isolation from chopped fruits. Patulin and Alternaria toxins were frequently identified in fresh fruits, while aflatoxins were also present in some fruits albeit at very low levels. Fungi were present in fruits entering the apple-puree production line, but not in apple puree after treatment at 95–105 °C. In contrast, the abovementioned mycotoxins were detected at all stages along the production line. Surprisingly, fumonisins were only detected after the apple puree was subjected to thermal treatment. Implications of these findings were discussed and few unresolved scientific questions were posed to stimulate further lines of study.

Development and performance evaluation of an electric cabbage harvester with a precise cabbage pushing mechanism

The manual method of harvesting cabbages is common in many Asian countries, which creates a lot of biomechanical problems among farmers. The existing commercial cabbage harvesters being bigger in size are not suitable for small landholdings. To address this, a three-wheeled walk-behind type electric cabbage harvester with a precise cabbage pushing mechanism was developed. It comprised a cutting unit, pushing unit, conveying unit, propelling unit, storage bin and handle. Based on the results obtained from laboratory tests, the cutting speed, forward speed and cutting position of cabbage stem from cabbage head was chosen as 590 rpm, 0.25 m/s and 0.1 cm. For pushing the cut cabbages precisely, a YOLOv8 custom cabbage detection model (mean average precision of 0.938) was developed and deployed in Nvidia Jetson Nano that could detect the cabbages and actuated a pusher via Arduino microcontroller and motor driver to push the cut cabbages to the conveyor belt. In the power supply unit of the harvester, 48 V 12 Ah, 12 V 7 Ah, and 24 V 18 Ah batteries were used for powering the motors for cutting, pushing, and propelling and conveying, respectively. The harvester was tested in a polyhouse for three Indian cabbage varieties. The maximum instantaneous power consumption (IPC) was measured as 948.53 W. Hand vibration and noise at operators’ ear level were 2.098 m/s2 and 78 dB(A), respectively, which confirmed its safety from an ergonomic perspective. The harvester achieved a maximum cutting efficiency of 77.5 % and a minimum damage rate of 7.5 % during polyhouse testing.

Recent Patents on Device or System Innovation in Pneumatic Conveying

Abstract: Coal is mostly stored in coal bunkers. As the amount of coal in the bunker increases, the concentration of coal dust inside the bunker also increases, making it susceptible to accidents such as fires and explosions. Additionally, the leakage of coal dust particles can cause significant environmental pollution in the surrounding area, leading to resource wastage. To improve energy efficiency, reduce material transport dust concentration, and protect the surrounding environment, the efficient, energy-saving, and environmentally friendly characteristics of pneumatic conveying systems are utilized. This is achieved through the use of anti-dust telescopic pipeline equipment (DTPE), which effectively prevents external dust particles from entering the telescopic pipeline, thus reducing mechanical wear. In environments with high coal dust concentration, a coal particle pneumatic conveying storage system based on DTPE is used to extend the service life of pneumatic conveying pipelines and effectively reduce the coal dust concentration within the storage bin. This study reviews the patents and research achievements of scholars in the field of pneumatic conveying and focuses on the anti-dust telescopic pipeline equipment (DTPE) and the coal particle pneumatic conveying storage system based on DTPE. Experiments using pneumatic conveying, screw conveyors, and belt conveyors are conducted to compare conveying time and efficiency. Dust reduction experiments are carried out in the coal bunker to verify the dust reduction effect of the coal particle pneumatic conveying storage system based on DTPE. The anti-dust telescopic pipeline equipment (DTPE) features a telescopic shell to protect the telescopic pipeline, effectively reducing mechanical wear caused by coal particles entering the gaps in the pipeline during pneumatic conveying. The coal particle pneumatic conveying storage system based on DTPE includes a cyclone dust removal system and a dynamic monitoring system, which monitors the temperature inside the bin and reduces the coal dust concentration, thereby minimizing the occurrence of safety accidents. Through experimental verification, the coal particle pneumatic conveying storage system based on DTPE is found to be suitable for environments with high coal dust concentrations. The anti-dust telescopic pipeline equipment (DTPE) and the coal particle pneumatic conveying storage system based on DTPE achieve the automated feeding, dust removal, return, and discharge of coal particles. They offer advantages such as high system automation, minimal environmental pollution, and high coal transport rates, providing design references for the pneumatic conveying of coal and other ore particle materials.

Can an old dog learn a new trick? Efficacy of livestock guardian dogs at keeping an apex predator away from people

Historic practices to reduce dangerous interactions between people, livestock, and large carnivores are returning alongside the recovery of some large carnivore populations. Emerging novel scenarios where people and carnivores interact make it important to identify nonlethal tools to reduce risk to people and facilitate coexistence. We tested an ancient practice in a novel way by placing livestock guardian dogs (LGDs) at farmsteads (i.e., areas with a family home and grain bins) with chronic interactions with grizzly bears (Ursus arctos). Grizzly bears are attracted to spilled grains around storage bins, causing concern over human safety near homes. Although we were only able to place five LGDs at four farmsteads, we found several lines of evidence supporting the use of LGDs to deter bears and protect people. There were 58-fold fewer camera-trap detections of bears visiting farmsteads with LGDs and an increase in behaviors suggesting bear discomfort compared to paired neighbor farmsteads that did not receive an LGD (i.e., control sites). After LGDs were deployed, there was an 87.8 % reduction in GPS-collar locations of bears within 300 m of farmsteads relative to before. Farmers had a positive experience using LGDs and would recommend them to others. Our results suggest LGDs could serve to protect specific locations and offer a new use of an old tool, but we recommend further research to broaden the scope of inference because of the small sample size of this study.

Mechanical stirring of bulk-stored maize in steel bins to suppress maize weevils and other beetle populations

This study investigates the effectiveness of periodic stirring as a non-chemical approach to suppress maize weevils, Sitophilus zeamais, and other beetle populations in large-scale grain storage bins. The research was conducted in a farm steel bin with a diameter of 9.8 m holding 127 Mg of maize, and a control bin of diameter 7.3 m holding 102 Mg of maize. Both bins were loaded with maize at 13% moisture and infested at a commercial tolerance rate of 2 weevils/kg of maize. Probe traps monitored beetle populations except for S. zeamais before stirring was initiated. Maize samples were collected at depths of 0, 0.9, 1.8 and 2.7 m with a vacuum-probe sampler prior to stirring and at 10, 20, 30 and 40 days of continuous stirring machine operation. Stirring achieved 100% control of live S. zeamais while the control bin experienced an increase in its S. zeamais population after 40 days. The stirring process also led to a significant reduction in dominant beetle populations such as hairy fungus beetles, Typhaea stercorea, and foreign grain beetles, Ahasuerus advena. Although the quality of maize in both bins changed at different depths and storage times, the treatment bin had higher bulk density (732.7 ± 3.98 kg/m3 to 768.9 ± 2.41 kg/m3), lower insect damage (0.02 ± 0.02% to 0.9 ± 0.28%), and higher allowable storage time (>249 days). Moisture content and molded kernels increased in the control bin, reaching 26.4 ± 1.29% and 3.2 ± 0.53%, respectively. The average percentage of broken corn and foreign material (BCFM) in the sweepings on the floor of the emptied treatment bin was 6.5 times higher than that in the control bin. Calculated packing factor values below 1.5 from the sweepings indicated that BCFM concentrations did not affect airflow. Stirring maize provides an alternative to the use of chemicals to control stored maize insect pests at a production scale.

Bacterial contamination of disinfectants: prevalence and students’ compliance with infection control practices

Contaminated disinfectants have been occasional vehicles of healthcare associated infections. To determine the presence and level of bacterial contamination of disinfectants used to decontaminate suction devices and to assess the extent to which students comply with infection control practices. A two-part cross-sectional descriptive study consisting of microbiological testing of disinfectants and a questionnaire based observation of students Unannounced observation of students disinfecting suction devices were recorded using a questionnaire. The process involved collecting a prepared disinfectant from a storage bin using a kitchen measuring jug. Specimens of disinfectants and swabs of jugs were collected for aerobic culture. Data pertaining to compliance with infection control practices was gathered. Only 33.6% of the students were observed unannounced. An overwhelming majority (84.9%) of students disinfected suction devices; 52% cleaned and disinfected the external surface of suction hoses and the spittoon bowl; 18.6% allowed the disinfectant to remain in the system long enough, and 14% advised their patients not to close their lips around the suction device. The majority of disinfectant samples (56.3%) as well jugs (55.6%) were contaminated with bacteria. Bacterial contamination of disinfectants was common in addition to poor compliance with infection control practices.

Cyclic Thermal and Structural Testing of a Hot Particle Storage Bin

Thermal energy storage is a key element in concentrating solar energy systems. In 2017 a Roadmap toward a third-generation system that could meet the SunSHOT goals of 0.06 $/kWe recommended increasing temperatures to > 700° C for heat transfer media to in-crease thermal efficiencies and lower levelized costs of heat. In 2021, the U.S. Department of Energy selected the particle pathway, G3P3, to build a 1 MWt prototype solar tower with 6 MWh thermal energy storage at the NSTTF in Albuquerque, NM. Of the primary components, the falling particle receiver, and particle-to-sCO2 heat exchanger have been demonstrated at the 250 kWt capacity. The storage component is now being demonstrated as part of the G3P3-USA and G3P3-KSA pilot plants. Storage bin liner materials have been demonstrated by KSU in 2016 and 2019. A flowing particle storage container was demonstrated in 2020 by KSU. The testing presented in this work will be the first to test the particle to wall interactions with mono-lithic refractory insulation, and to validate a transient thermal transport model with the unique kinetics of bulk solids in funnel-flow where cooler particles near the walls flow inward toward a hot central flow channel. This work will also de-risk and characterize the specific design of the G3P3-USA storage bin.

Seasonal Performance Characterization of a Gen3 Particle-Based Concentrating Solar Plant With a Spatially Resolved Transient Thermal Storage Model

Particle-based Gen3 Concentrating Solar Power (CSP) can be paired with high-temperature power cycles (>700 °C) and can have built-in long duration (≥10 hours) thermal energy storage if the working particles are stored properly in thermal energy storage bins. Although high-temperature and long-duration thermal energy storage can mitigate daily intermittencies in solar irradiation, seasonal variability in local meteorological conditions can still have a significant impact on the overall performance of CSP systems. Aside from daily cloud coverage affecting incident solar radiation, wind speed and ambient temperature are also significant variables regarding system heat attenuation, component efficiency, and overall solar conversion efficiency. In this work, we present simulation results for a Gen3 CSP prototype system in operation over four weeks throughout the year in Albuquerque, NM. The meteorological conditions are taken directly from the TMY3 data at the Albuquerque International Sunport, where the hourly Direct Normal Irradiation (DNI), wind speed, and ambient temperature are of particular interest. An investigation of the sensitivity of individual components like storage and ducting to the local meteorological conditions is provided and extended to the overall performance of the CSP system. The results from this study show that the particle inlet temperature at the particle-to-sCO2 heat exchanger can change as fast as 30 °C/min under standard operation in a passive mode.

Plot Scale Evaluation of the Hydrologic and Water Quality Benefits of Blue Roofs Compared to Green and Conventional Roofs

Highlights There were no significant differences (a = 0.05) in rainfall retention between blue and green roofs. Blue roofs appear to be a viable option to green roofs when the priority is stormwater management. Blue and green roofs need to be studied on larger scales to gain more confidence in the treatment provided. Abstract. Impervious surfaces caused by urbanization alter hydrologic conditions. In ultra-urban areas (75% or more impervious), rooftop stormwater control measures (SCMs), such as green roofs, exploit underutilized rooftop space. Green roofs reliably attenuate rainwater, but associated water quality treatment results are not as consistent. This study explored the viability of blue roofs, an emerging technology, as an alternative to green roofs. Nine adjacent plots consisting of three each of conventional (control), green, and blue roofs were constructed in Raleigh, NC. As a part of hydrology monitoring, on-site rainfall was measured using a tipping bucket and verified using a manual gauge. Water quantity data were collected using water level loggers in storage bins placed under the roof plots to record outflow. Measured rainfall retention was similar for blue and green roofs, and both systems were significantly (a = 0.05) and substantially (50%) more retentive than control roofs. A comparison of evaporation rates suggested blue roofs may be more effective at regenerating storage capacity than green roofs. Thirteen water quality events were sampled, and the mean total nitrogen (TN) concentration from the green and blue roofs was 5.83 and 2.18 mg/L, respectively. Similarly, the mean total phosphorus (TP) concentration from the green and blue roofs was 2.75 and 0.25 mg/L, respectively. Total suspended solids (TSS) data were collected, but seven of 13 samples were below the practical quantitation limit (2.5 mg/L), and the data were not statistically analyzed. Total kjeldahl nitrogen (TKN), TP, and orthophosphate (O-PO4 3-) concentrations from green roof treatments were significantly (a = 0.05) larger than concentrations from blue roofs. Except for nitrate/nitrite nitrogen (NO2,3-N), there were no significant differences between blue and control roof pollutant concentrations. However, green roofs often discharged substantially higher pollutant loads than control roofs for every pollutant other than NO2,3-N and total ammonical nitrogen (NH3-N). While blue roofs may lack the aesthetic appeal of green roofs, this study suggests blue roofs are a relatively cost-effective option, likely preferable, when solely focused on the benefits of stormwater management from rooftops. Keywords: Blue roofs, Conventional roofs, Green roofs, Hydrology, Monitoring, Stormwater control measures, Water quality.

Effect of structural characteristics on the transport characteristics of solid particles in the thermal storage and release system of circulating fluidized bed

Coal-fired power generation stands as the most economically viable modulating power source in present-day China. It holds the potential to offer prospective solutions to the challenges posed by the rapid expansion of intermittent, unpredictable, and unstable renewable energy sources. Solid particle thermal storage technology emerges as an effective means to enhance the flexibility of coal-fired circulating fluidized bed power units. To attain an optimized structure for the solid particle thermal storage and release system in circulating fluidized bed units, experimental research was conducted on a 0.1 MWth circulating fluidized bed test platform. This study delved into the impact of ash storage bin geometries and the shapes of their feed-discharge valves on the control properties of solid particle transportation. The experimental outcomes reveal that employing inverted m-shaped valve and dual U-shaped valves for feed control, alongside U-shaped valves and N-shaped valves for discharge control, both enable efficient and rapid storage and release of solid particles within the circulating fluidized bed. Under similar air distribution conditions, the inverted m-shaped valve exhibits lower conveying energy consumption than the dual U-shaped valves, while the N-shaped valve excels in control characteristics over the U-shaped valve. Furthermore, the inverted m-shaped valve and the N-shaped valve demonstrate optimal overflow port heights, and the ash storage bin exhibits an optimum height-to-diameter ratio.

Investigating different manual picking workstations for robotized and automated warehouse systems: Trade-offs between ergonomics and productivity aspects

Robotized and Automated Warehouse Systems are widely used in logistics systems due to their efficiency and compactness. Among all aspects to include during tactical and strategic decisions, the number and the design configuration of the picking workstations represent the most critical decision since they influence the conveyor system path and length and the efficiency and productivity of the entire logistics system. Further, the proper workstation design reduces ergonomics risks and, thus, ensures a better quality of work and safety. Nevertheless, many studies on parts-to-picker systems have focused on global system performance, while ergonomics and their influence on system efficiency have often been neglected.For these reasons, in this paper, we aim to close the gap by investigating both ergonomic assessment and picking workstation configurations in an integrated way. Based on the results obtained, managerial guidelines are provided by highlighting the pros and cons of each configuration. Results demonstrate that the suitable solution depends heavily on the delivery order profile and on the time necessary to pick a customer order line. Configurations with the storage bins placed inclined, placed above the order bin and in front of the worker lead to better posture and lower picking time. Further, additional parameters, such as the time required to change the storage bin, the number of items to pick from each storage bin, strongly influence the choice of the most suitable configuration. The results of this paper represent fundamental guidelines to allow managers to carry out correct feasibility studies in terms of expected costs, performance and required spaces.

Coupled abrasion Erosion-Oxidation wear from particles in Concentrating solar thermal power facilities

Solid particles represent an attractive heat transfer and energy storage media for next generation solar thermal power facilities for their ability to operate at high temperatures without concerns for freezing or corrosion. A potential outstanding issue that still remains for particles as heat transfer media is the wear on components operating with particles flowing (sliding) in, along, or over them. Prior work has shown that even at the low velocities (∼1 cm/s to ∼ 1 m/s) expected in solar thermal facilities, material wear will still occur, and the lifetime and performance of components undergoing wear needs to be well understood. Abrasion erosion occurs when particles come into contact with containment materials at extremely shallow angles, and is likely to be seen in heat exchangers, storage bins, and flow control mechanisms. Additionally, because of the open nature of most of these systems to air, oxidation of metals is also of concern. Here, we show how critical the coupled erosion-oxidation mechanism is to understanding particle/material durability and therefore need for greater in-depth analysis. Abrasive wear experiments are conducted on metals such as SS316 (L and H grades), Inconel 740H, Haynes 230 with different particles (HSP 40/70, Wedload 430, and CarboMax HD) for different operating conditions. Results clearly indicate that oxide spallation and removal is critical to the overall wear seen at high temperatures.

Experimental study on rolling segregation of cement stabilized macadam

Indoor simulated mixing building storage bin unloading, forming conical piles. The effects of falling distance, mixing time and water content on rolling segregation of cement-stabilized macadam were analyzed by three indexes, including repose Angle of pile, key sieve passing rate and cement dosage. The results show that the segregation of mixture can be increased significantly with the increase of drop distance. The separation degree of the mixture can be effectively controlled by controlling the unloading distance within 70 cm. Mixing time has little effect on the Angle of rest and gradation segregation of the mixture, but has significant effect on the distribution uniformity of cement. Indoor mixing time should reach more than 45 s. When the mixing water content is less than the optimal water content, the segregation of the mixture is serious. When the moisture content increased to 1.5 %, the mixture showed obvious bleeding phenomenon. The mixture shall not be lower than the optimal moisture content before the crushing is completed, and the moisture content increase shall not exceed 1.5 % of the optimal moisture content as far as possible.

Study of the Influence of Variable Ambient Temperature on Heat Transfer Inside Different Sized Grain Storage Bins

The following work aims to present the numerical solution for a two-dimensional and transient model for heat transfer on storage bins during the period of one year, in which it was supposed that the structure is exposed to ambient temperature, which depends on time. From this hypothesis, it was executed curve fitting of a relation between those quantities, using meteorological data from the city of Pelotas/RS in the year 2021, and the influence that the outside temperature of a bin has over the process of heat transfer that occurs inside the structure was analyzed. Upon executing simulations of heat transfer inside fictitious bins located in this southern Brazilian city, results show that the boundary condition causes considerable variations in grain temperature, which are more intense in points near the bin's surface. Furthermore, it was concluded that containers of least storage show larger variations in inner temperature during the analyzed period when compared to the behavior of bins containing larger sizes.

Algoritmo genético no projeto de silos de soja visando a homogeneização do fluxo de ar

ABSTRACT One of the main processes used to maintain grain quality in large storage bins is aeration. An optimization model that considers the limited and discrete nature of the air inlets, in addition to the geometric characteristics of the storage bin, could produce results more easily applicable results for the design of new grain storage bins. The objective of this study was to parameterize and to apply the Darcy-Forchheimer model for simulating airflow in soybean grain mass as function of grain layer height, and develop an artificial intelligence method based on genetic algorithm for optimizing grain storage bin dimensions and air inlet configurations to obtain a more homogeneous airflow in the grain mass. The parameterization considered the effect of grain compaction and the OpenFOAM simulations showed good agreement with the experimental data. The proposed genetic algorithm was able to increase the airflow homogenization when compared to the grain storage bin used as reference.

Study of Water–Sand Inrush through a Vertical Karst Conduit Uncovered through Tunnel Excavation

The existence of karst compromises the safety of underground engineering, especially during tunnel excavations. Karst conduits are uncovered through tunnel excavations, which may lead to a water–sand inrush disaster. Taking a vertical karst conduit as an example, the process of water–sand inrush through a karst conduit could be viewed as being similar to the process whereby a water–sand mixture flows through the discharge opening of a storage bin. In this study, based on force analysis of a non-aqueous sand body above a karst conduit, the limiting diameter of the karst conduit under force equilibrium was obtained. Considering the effect of water on aqueous sand bodies, the criterion of water–sand inrush was established. We aimed to study water–sand migration and inrush through vertical karst conduits in order to obtain the distribution of the water pressure near a vertical karst conduit, and to explore the relationship between the conduit size, water pressure, and water–sand flow rate; therefore, a simulated testing system for analyzing water–sand inrush through a vertical karst conduit was developed. When the water pressure in the testing chamber was close to the critical head pressure of the water–sand inrush, the water–sand inrush exhibited a pattern of instability—migration—deposition—stability. When the water pressure in the testing chamber exceeded the critical head pressure, the water–sand flow increased first and then stabilized over time. With the increase in the set values of the water pressure and conduit size, the steady flow of the water–sand mixture increased gradually. When the karst conduit was opened suddenly, the actual water pressure in the testing chamber decreased significantly, due to the water–sand mixture flowing out of the testing chamber and the water supply lagging behind. With the stabilization of the water–sand flow, the actual water pressure gradually tended towards stability, but it was still lower than the initial set water pressure. When the karst conduit was opened, the values of the water pressure monitored by the pore pressure gauges all clearly decreased. With the stabilization of the water–sand flow, the water pressure gradually became stable. With the increase in the distance between the pore pressure sensor and the karst conduit, the water pressure values all increased gradually. These test results are significant for further studies of the formation mechanisms of water–sand inrush through vertical karst conduits.

Would You Like Wood or Plastic? Bin Material, Sanitation Treatments, and Bin Inoculum Levels Impact Blue Mold Decay of Stored Apple Fruit.

Blue mold, caused primarily by Penicillium expansum, is a significant postharvest disease of apples. It not only causes economic losses but also produces mycotoxins that contaminate processed fruit products, which contributes to food waste and loss. Previous research has shown that packing and storage bins harbor Penicillium spores and that steam and hot water efficiently reduce spore inoculum levels. However, studies using wooden and plastic bins regarding their ability to harbor spores, the effect of chemical sanitation treatments on spore levels, and the impact of rinsate from treated bins on apple fruit decay have not been investigated for the Mid-Atlantic area (Okull et al. 2006; Rosenberger 2009). We evaluated different sanitation treatments (chemical and physical) to reduce P. expansum inoculum levels on wooden and plastic bins. We determined that wooden bins bound P. expansum spores four orders of magnitude higher than plastic. When both bin types were treated with steam (wooden) or sterile hot water (plastic), Thyme Guard, or Academy, all treatments resulted in significantly (P < 0.05) lower spore levels compared to untreated controls. Although, plastic bins retained lower numbers of spores after inoculation with contaminated spore rinsate and required much higher concentrations of P. expansum spores in rinsate to retain spores at levels that would lead to decay on apple fruit. Overall, we demonstrated that plastic bins retain fewer spores than wooden bins and that both can be sanitized by various physical or chemical treatments. We envision that our findings will be applicable in the future as the techniques implemented in this study were used to investigate industry-relevant questions. Our goal is that the research techniques and findings become feasible with advancements in technology and/or accompany other shifts in existing processes in commercial pome fruit packing and storage facilities.