Surface Of Tank Research Articles

Concept of a Cyber–Physical System for Control of a Self-Cleaning Aquaponic Unit

The article aims to present a cyber–physical system (CPS) to support the cultivation of aquaculture in a closed aquaponic system using the deep-water culture (DWC) method. The CPS uses precision sensors as TriOxmatic 700 IQ (for dissolved oxygen and water temperature), AmmoLyt Plus 700 IQ (for ammonium), NiCaVis 701 IQ NI (for nitrites and nitrates), SensoLyt® 700 IQ (for pH), and SL-M5 (for water level). It is built with a Raspberry Pi 4, 8 GB as a server, OpenHAB 3.0 software, and other specialized software for measuring water parameters. Some of the parameters are maintained completely autonomously, while others are indirectly controlled. Basic knowledge of hydroponics and aquaculture is required to set up the system, but day-to-day maintenance can be carried out by employees who receive instructions from the CPS. A method for the physical modification of the fish tank surface by using laser processing is proposed. This results in a change in surface topography (creating diverse microstructure patterns) and its roughness, which is of crucial importance for the bacterial adhesion mechanism.

Developing a plant microbial fuel cell by planting water spinach in a hanging-submerged plant pot system

To plant crops (especially dry crops such as water spinach) with concomitant electricity recovery, a hanging-submerged-plant-pot system (HSPP) is developed. The HSPP consists of a soil pot (anodic) partially submerged under the water surface of a cathode tank. The microbial communities changed with conditions were also investigated. It was found that with chemical fertilizers the closed-circuit voltage (CCV, with 1kΩ) was stable (approximately 250mV) within 28d; however, without fertilizer, the water spinach could adjust to the environment to obtain a better power output (approximately 3mWm-2) at day 28. The microbial-community analyses revealed that the Pseudomonas sp. was the only exoeletrogens found in the anode pots. Using a secondary design of HSPP, for a better water-level adjustment, the maximum power output of each plant was found to be approximately 27.1mWm-2. During operation, high temperature resulted in low oxygen solubility, and low CCV as well. At this time, it is yet to be concluded whether the submerged water level significantly affects electricity generation.

PERFORMANCE OF WATER COOLING FOR RADIATION HEAT FLUX FUEL STORAGE TANK

Full-surface fire on fuel storage tank emits high radiation heat transfer. As a fire protection strategy, the water curtain cooling system is activated to reduce the temperature on the adjacent tank surface. Therefore, the present work predicts and analyses the radiation heat flux and the maximum flame temperature of different types of fuels. Further, this analyses the effect of fuel total mass on radiation heat flux and maximum flame temperature and observes the effect of distance between two tanks on radiation heat flux distribution. The relationship between water cooling flow rate and outlet water temperature that absorbed radiation heat flux has been studied. The study has been conducted by using the Consequence modeling software trial version. The modeling setup of the tank is 17 m in height with 65 m inner diameter, and the meteorological data used are 5.4 m/s wind speed with north wind direction at atmospheric pressure in order to imitate the worst-case fire scenario. The results reveal that the gasoline fuel emitted the highest heat flux value of 11.03 kW/m2 and the raw gasoline sample emits the lowest heat flux value of 9.14 kW/m2. Furthermore, the total mass of the fuel shows no effect on the maximum flame temperature of 958.51°C. According to the findings, the critical tank distancing is 36 m and thus the appropriate tank distancing of 40 m is highly recommended by the standard. The result shows that the water cooling rate of 4.1 lpm/m2 is an excellent practice of water cooling to cool down the temperature of the fuel tank which is exposed to radiation heat flux.

Dynamic response of spherical tanks subjected to the explosion of hydrogen-blended natural gas

Hydrogen is a renewable and clean energy and obtains increasing attention all around the world. Blending hydrogen into natural gas can promote hydrogen development and storage tank farms play an essential role in the storage of hydrogen-blended natural gas (HBNG). However, upon leakage from the tank, HBNG accumulates to create a vapor cloud and may explode, resulting in more severe consequences than natural gas. Furthermore, the explosion has the potential to trigger the domino effect in the spherical tank storage area, leading to multiple explosions. But little attention has been paid on this research issue. This article analyzes the dynamic response of the spherical tank exposed to HBNG explosions. The fluid–structure interaction theory is adopted to establish the whole finite element model. Meanwhile, the advanced Arbitrary Lagrangian-Eulerian (ALE) method can reduce mesh distortion and enhance computational accuracy, and the process of explosion is analyzed through the coupling of the Lagrangian mesh for the structure and the Eulerian mesh for the vapor cloud. Then, the algorithm is employed that couples shell elements with solid elements by utilizing a penalty function. Besides, the dynamic response of the spherical tank and pillar surfaces is analyzed in the trends of effective stress, displacement, velocity, and structural damage under various parameters, evaluating the energy absorbed by the spherical tank and pillar. Accordingly, the equipment damage caused by HBNG explosions considering possible damage caused by secondary explosions can be obtained. Then, the effects of the HBNG explosion chain on equipment are analyzed in tank areas. The dynamic response of structures in the explosion is closely related to the different hydrogen blended ratios, distances, and structural thickness, which significantly impact the effective stress of the spherical tank and pillar. Moreover, the damage caused by the HBNG explosion is more serious for pillars than the spherical tank, making the role of pillars crucial in supporting the spherical tank. The results obtained in this study can be used to support the design and safety operation of HBNG storage areas.

Structural Problems Occurring in Reinforced Concrete Drinking Water Tanks and Water Loss Prevention Methods

Water losses occur over time due to structural deformation in buried reinforced concrete tanks built to meet the drinking water needs in living spaces. It is clear that drinking water tanks must be strengthened and waterproofed to prevent tons of water loss every year. A water-repellent coating on the concrete surface of water tanks prevents water loss as well as effectively protecting the concrete and increasing its durability. Waterproofing not only provides protection, but also prolong one's life of the building. The key to success in waterproofing all engineering structures is the proper and appropriate application of the right waterproofing materials. The aim of this study is to prevent water losses due to structural problems that occur over time in four recessed rectangular prismatic reinforced concrete clean water tanks in four different locations in a province in Turkey, to extend the life of the facility and most importantly to provide cleaner potable water to human life. Water and Sewerage Administration started maintenance, repair and waterproofing works of 15,000 m3 water tanks in the city center in 2021-2022. This article, academic articles, previous practices have been researched and it is hoped to be a solution to the problems. Considering the causes of water loss in the existing water reservoir, it is hoped that it will be a guide for the construction of a new water reservoir.

Study on Thermal Characteristics of Winding under Inter-Turn Fault of Oil-Immersed Transformer

The inter-turn fault is a common fault of oil-immersed transformers. Due to the deterioration of inter-turn insulation, its resistance decreases, which leads to an increase in the winding coil current and loss, causing the winding temperature to rise. Therefore, analyzing the electrothermal characteristics of inter-turn short circuit faults in oil-immersed transformers can provide a theoretical basis for the diagnosis of inter-turn faults in transformers. This paper studies the equivalent circuit under inter-turn faults and establishes a field–circuit coupling model to calculate the current characteristics under different inter-turn short circuit faults of transformers. The distribution of coil losses under faults is calculated as thermal source excitations, and a thermal–fluid-coupled calculation model for oil-immersed transformers is established. After the experimental verification, it is found that both the errors between the winding and tank surface temperatures do not exceed the acceptable limits, validating the effectiveness of this model. Using this model to calculate the temperature distribution for various inter-turn short circuit faults in transformers reveals their hot-spot characteristics. The results indicate that under inter-turn fault conditions, the temperature at faulty turns will gradually increase towards a limit, eventually leading to coil damage. This research provides theoretical support for enhancing transformer detection and diagnostic capabilities.

Optimising the hygiene of a liquid feeding system to improve the quality of liquid feed for pigs

Poor feeding system hygiene may contribute to uncontrolled spontaneous fermentation in liquid pig feed and its associated undesirable effects. This study aimed to determine the effects of an intensive sanitisation programme in a grow-finisher liquid feeding system by monitoring microbiological and physico-chemical parameters of liquid feed and microbial colonisation of the feeding system surfaces. The sanitisation programme involved a combination of physical and chemical cleaning between batches of grow-finisher pigs, combined with nightly rinsing of the system with an organic acid blend. Improved hygiene of the internal surfaces of the mixing tank and feed pipeline, particularly until week 5 post-cleaning, was evidenced by reduced counts of lactic acid bacteria, total aerobes, Enterobacteriaceae, yeasts and moulds and decreased adenosine triphosphate concentrations. Enterobacteriaceae and moulds remained undetectable on pipeline surfaces for 10 weeks. Scanning electron microscopy of the feed pipelines confirmed these findings. Conversely, the impact on liquid feed microbiology was minimal and short-lived. However, acetic acid, ethanol and biogenic amine concentrations decreased in the feed post-cleaning and no gross energy losses were observed. Therefore, by controlling surface microbial communities on liquid feeding systems via implementation of the sanitisation programme developed in the current study, on-farm liquid feed quality should be improved.

Distribution characteristics of radiant heat flux on tank surfaces exposed to wildland fires

AbstractThe expansion of wildland‐urban interface tends to expose fuel tanks to wildland fires, the frequency and intensity of which have increased in recent years due to climate change and global warming. This study aims to examine the distribution of radiant heat flux on a tank surface exposed to a wildland fire front, with a particular focus on extreme wildland fires. A theoretical framework is proposed, which consists of a flame length correlation, a thermal radiation model, and a correlation of time to failure, to calculate the radiant heat flux received by the tank surface and the potential for tank failure. The horizontal and circumferential distribution characteristics of the radiant heat flux are intensively discussed, in terms of the heat flux profile, heating area, total heat, time to failure versus the fireline intensity, fireline width, spacing, and tank volume. In particular, extreme wildland fires, characterized by large fireline intensities, could potentially destroy the tank within the safety spacing mandated by the current regulations. Therefore, a comparison between the time to failure and the radiant heating duration is suggested to ascertain the necessary safety spacing. The uncertainties in model calculations are also addressed, which arise from the use of different flame length correlations and flame radiative fractions.

Wetsuit Thermal Resistivity Measurements.

In recent years, attention to the realization and characterization of wetsuits for scuba diving and other sea sports or activities has increased. The research has aimed to establish reliable and standardized measurement methods to objectively assess wetsuit quality, particularly focusing on their mechanical and thermal properties. In this work, we describe and compare two different measurement methods for the characterization of neoprene wetsuit thermal resistivity. The first method follows the existing regulations in the field, while the second one, which we are originally proposing in this paper, offers an alternative yet accurate way based on a simplified experimental set-up and easier measurements. In both cases, the wetsuit sample under testing was shaped in the form of a cylindrical sleeve of proper dimensions and wrapped around a phantom containing water at a higher temperature and surrounded by water at a lower temperature. The wetsuit's cylindrical surface allows heat flow from the warmer water on the inside to the colder water on the outside through the wetsuit area. In the first case, a thermal steady state was achieved, with constant heat flow from the phantom to the exterior. This was obtained with a power balance between two homogenous quantities. Electrically supplied thermal heating within the phantom was used to balance the thermal energy naturally flowing through the wetsuit's surface. In this first case, a stable and fixed temperature difference was obtained between the inner and the outer surfaces of the wetsuit sample. In the second case, a thermal transient was analyzed during the cooling process of the phantom, and the thermal time constant was measured, providing the sample thermal resistance once the phantom thermal capacity was known. In both cases and methods, the heat flow and thermal resistance of other elements than the wetsuit must be evaluated and compensated for if they are not negligible. Finally, the thermal resistivity per unit area of the wetsuit material was obtained with the product of the wetsuit sample's thermal resistance and the wetsuit area. The measurements, conducted until now by immersing the phantom in a free surface tank, show that both methods-under stationary and under transient temperature conditions-were valid to assess the wetsuit's thermal resistivity. The stationary method somehow provided better accuracy while involving less well-known parameters but at the expense of a more complicated experimental set-up and additional energy consumption. The transitory method, on the other hand, is quite easy to implement and, after careful characterization of the phantom's parameters, it provided similar results to the stationary one. An uncertainty budget was evaluated for both methods, and they did provide highly compatible measurement results, with resistivity values of 0.104(9) m2·K/W (stationary method) and 0.095(9) K·m2/W (transient method) for the same wetsuit sample under testing, which is also consistent with the values in the literature. We finally propose that the novel method is a valid alternative for characterization of the thermal insulation properties of a scuba diving wetsuit.

Design and study of novel square electromagnetic sensing based on stepped eddy current thermography

Nondestructive testing of internal corrosion defects is a key task to evaluate whether the material is repaired and replaced. In this paper, a novel square ferrite magnetic open sensing structure is designed for detecting volumetric corrosion defects on the inner surface of oil and gas storage tanks. A theoretical model of the structure is developed and the characteristics of the guided distribution of the electromagnetic field are resolved. The proposed model provides a region of interest with a uniform magnetic field. This greatly improves the detectability and thermal comparison of corrosion defects on the inner surface. In addition, the inspection is performed under weak excitation conditions and in the full open field of view of the infrared camera. This configuration greatly improves the portability and efficiency of workpiece inspection. Several open architecture sensors are evaluated and compared regarding temperature rise uniformity, model passability, and lightweight level. Meanwhile, the geometrical parameters of the square sensor, the operating parameters, and the material properties of the detected samples are investigated, including the coil height, the cross-arm length, the lifting distance, the operating frequency, the relative magnetic permeability of the sample, and the electrical conductivity of the sample. Finally, the detection capability of the sensors was verified through experiments with different steel plate thicknesses and defect morphologies.

A PHITS based-computational model of a TRIGA-fueled subcritical reactor for gamma dose mapping

Since 1988, the Philippines lacked local access to a nuclear facility, creating a significant void in this field of study for Filipinos. However, after a hiatus of 34 years, this gap was addressed with the recent authorization granted to Philippine Research Reactor 1 (PRR-1) Subcritical Assembly for Training, Education, and Research (SATER), allowing it to resume operations. In this work, a PHITS-based computational model was developed for the recently commissioned PRR-1 SATER. The model utilized a simplified model of the Training, Research, Isotope, General Atomics (TRIGA) fuel that releases photons with 0.6617 MeV energy from the Cs-137 fission product in the fuel. Compared to previous works on photon transport mapping, which utilized average source definition, this study employed individually defined fuel intensities and compared them with the averaged source definition for the fuel. The two fuel source definitions showed noticeable differences inside the reactor tank which is relevant for mixed-field irradiation applications of a research reactor. However, defining the fuel rods by their average strength is sufficient for radiation protection purposes. Simulations were also performed for fuel source definitions based on the average and ±1 standard deviation of the gamma intensity. Gamma doses received by cylindrical phantoms positioned at 0.5 m from the surface of the reactor tank for 500 h were found to be 1 % of the radiation dose limits per year and 4 % of the average dose limit for 5 years as stipulated by the Code of Philippine Nuclear Research Institute (PNRI) Regulations. Loss of water accident was also analyzed based on a conservative exposure time of 500 h. This resulted in a dose value that is only 45.5 % of the dose identified as the emergency turnback guidance of the IAEA. Lastly, PHITS calculated values of gamma doses were found to agree well, with 0.98 ratio, when compared with gamma doses measured at specified locations in the reactor. Results of this study confirm the inherent safety of the PRR-1 SATER in terms of radiological shielding for Cs-137 photons.

Beyond the surface: A comparative study of intraoral scanners in subgingival configuration scanning

ObjectivesThis study conducted a comprehensive comparative analysis of three intraoral scanners (CEREC Primescan, TRIOS, CEREC Omnicam) and a lab scanner (inEosX5) assessing their precision in simulating subgingival tooth preparations. MethodsUtilizing a dental simulation mannequin with a 3D-printed resin structure, 100 structures with depths ranging from 0.5 to 4.0 mm were created within a square mimicking a rectangular tank surface. Four scanner groups (A-D) and five subgroups were established. Two digitization methods, a customized parallelometer and an intraoral simulation, were applied, ensuring a standardized scanning sequence. Trueness was evaluated by comparing CAD-calculated surface areas with actual dimensions, and qualitative trueness analysis was conducted using MeshLab. Surface areas were computed using the formula SA = 2lw + 2lh + 2wh. Statistical analyses, including Pearson’s correlation coefficient, Kolmogorov–Smirnoff and Levene’s tests, three-way ANOVA, and paired sample t-tests, elucidated relationships and differences (a=0.05). ResultsA robust correlation (r = 0.850, p < 0.001) between intraoral scanner choice and scanned area depth was found. Inverse correlations were noted for experimental methods. Three-way ANOVA demonstrated significant scanner-depth interaction (F(12,760) = 760.801, p < 0.001). SignificanceEmphasizing high-resolution sensors and advanced technologies, the study underscores the optimal choice for subgingival digitization, acknowledging variations among scanners.

A combination approach for optimization operation of multi-objective cascade reservoir systems (Case study: Karun reservoirs)

ABSTRACT Multi-reservoir systems that have diverse and conflicting objectives are challenging to design due to their uncertainties, non-linearities, dimensions and conflicts. The operation of multi-reservoir systems is crucial to increasing hydropower production. In this study, we have investigated the application and effectiveness of the new optimization algorithm MOAHA in multi-objective cascade reservoirs with conflicting objectives, and it has been investigated on a case-by-case basis on Karun cascade reservoirs (Karun 3, Karun 1, Masjed Soleyman and Gotvand). The suggested method (MOAHA) output with other optimization algorithms, MOALO, MOGWO and NSGA-II, were compared and evaluation criteria were used to select the best performance. Additionally, we employed the powerful TOPSIS method to determine the most suitable algorithm. The considered restrictions have also been observed. The results indicate that MOAHA's proposed method is better than the compared algorithms in solving optimal reservoir utilization problems in multi-reservoir water resource systems. The reduction of evaporation (losses) from the tank surface by 9% is accompanied by a 15% increase in hydropower energy production. MOAHA, scoring 0.90, is deemed the best algorithm in this study, whereas MOGWO, with a score of 0.10, is regarded as the least effective algorithm.

Sound pressure level determination around the transformer using coherent and incoherent analytical summation methods

In this paper, coherent and incoherent analytical summation methods from elementary sound sources on the transformer’s tank are presented. They aim to determine a one-third-octave spectrum of sound pressure levels (SPL) in points around the transformer. Each part of the transformer’s surface is treated as a separate plane source so the analytical calculation can be applied to find SPL in the surroundings. Reflections from the ground are also considered by putting an image of the plane sources on the other side of the reflecting plane and adding its contributions to the total pressure in the desired points. Grid-like vibration measurements of vibration velocity on the tank surfaces are used as input parameters. Vibrations and sound pressure levels are measured to validate the method on the 5 MVA transformer experimental object. The SPL around the transformer in short-circuit (SC) and open-circuit (OC) tests is measured in the semi-anechoic chamber to compare it with theoretical results. By analyzing the results, the coherent calculation with reflection provided the most accurate results. In the SC operating condition, the normalized root mean square error (NRMSE) is 17.2%, and in the OC operating condition, it is 10.9%. The novelty of the presented method is that it considers complicated transformer geometry where each surface is calculated as a separate noise source. It calculates noise at a distance from the elementary vibration sources, considering phase and reflection from the hard ground, and provides detailed noise maps that can be used for noise modeling around the substations.

Heat Transfer Analysis of Insulation Material for the Reserve Hot Water Tank

A domestic hot water tank represents a significant potential demand-side management asset in energy systems. The selection of insulation materials is crucial for maintaining the temperature of the hot water tank and preventing massive heat loss from the tank. This study aims to analyze the different combinations of insulation material for the reserve hot water tank. Several materials, such as plywood, white bricks, red bricks, plasticine, aluminum foil, styrofoam, fine sand, and glass, were used as the insulation layer in experiments. Seven combinations of insulation layers were made to insulate the mini reserve water tank in the experiment. The insulation layers covered the surface of the water tank, and the initial and final temperature of the hot water was measured. The heat loss from the hot water tank and the thermal resistivity of the insulators were also studied. The experimental results revealed that the combination of plastic, plasticines, styrofoam, and timber yields the lowest heat loss for the hot water tank. This finding indicated that the material with low thermal conductivity is the best insulator for preventing heat loss from the thermal system. Thus, this study is useful in designing and selecting the insulation materials for the reserve hot water tank for domestic and industrial use.

Design and Fabrication of Automated Water Tank Cleaner

Abstract: To develop a mechanical system for cleaning automatic cylinder water tank. The mechanical system consists of water tank, electrical motor, shaft, handle for supporting frame and converter. Converter is used to supply the required voltage to the motor. As the power input is given to the electric motor. The mechanical system includes screw mechanism. A screw mechanism is a mechanical device that converts rotational motion into linear motion. It consists of a threaded shaft, known as a screw, and a nut with matching threads that engage with the screw. When the screw is rotated, the nut moves along the screw axis, resulting in linear motion of the nut. This arrangement is used to transport the entire mechanical system up and down for cleaning cylinder water tank. Brushes are connected to the shaft through coupling. When motor gets starts the energy transfers into the shaft. It cleans the interior surface of the cylinder water tank. The purpose of this project is to reduce the human efforts and to avoid the chemical influence on health of person entering the tank for cleaning. To overcome this cleaning tanks overhead manually is a critical job. So, we designed an automated cleaner with provide a high safety, better efficiency, and to reduce the time for cleaning

Visible light-driven Cl-g-C3N4 activated peroxydisulfate process for TMP efficient degradation in a wide pH range

A narrow pH-applicability range can impact the actual treatment efficiency of AOPs, so the application of a wide pH range in AOP technology has garnered significant attention. In this study, the Cl-doped g-C3N4 as a visible light catalyst to activate the peroxydisulfate (PDS) process, named Vis/Cl-g-C3N4/PDS, was developed for trimethoprim (TMP) degradation in a wide pH range of 3–11. Results show that the Vis/Cl-g-C3N4/PDS process exhibited degradation efficiencies for TMP that were 1.39 times and 7.74 times higher than those of the Vis/Cl-g-C3N4 process and the Vis/g-C3N4 process, respectively. The Vis/Cl-g-C3N4/PDS process perfectly achieved degradation rates of over 98 % for TMP within a wide pH range of 3–11. It concluded that the high efficiency of the Vis/Cl-g-C3N4/PDS process in degrading TMP over a wide pH range was caused by the two co-existing reactive oxygen species (ROS) generation mechanism pathways: the photocatalytic activation of PDS and the light-assisted hydrolysis of PDS. Moreover, after 3 h of illumination in the Vis/Cl-g-C3N4/PDS process, a degradation range of 85.7 %–97.8 % was demonstrated in various real water matrices including of tap water, secondary sedimentation tank effluent, surface water, and aquaculture water. This study provided practical significance for the practical application of AOPs in water environmental pollution control.

Two novel bacteriophages isolated from the environment that can help control activated sludge foaming.

Nocardia spp., which belongs to one of the Nocardio-form filamentous bacteria, is usually surface hydrophobic and when overproduced attaches to the surface of bubbles under the action of surfactants, allowing the stable presence of foam on the surface of aeration tanks, leading to the occurrence of sludge-foaming events. Two novel phages, P69 and KYD2, were isolated from the environment, and their hosts were Nocardia transvalensis and Nocardia carnea, respectively. These two phages are Siphophages-like with long tails. An aeration tank pilot plant was constructed in the laboratory to simulate sludge foaming, and these two strains of phage were applied. Compared with the reactor not dosed with phage, the application of phage could reduce the host level in the reactor, resulting in the highest decrease in turbidity by more than 68% and sludge volume index by more than 25%. The time for surface foam disappearance was 9h earlier than that of the control group (the group with the same concentration of Nocardia carnea but no bacteriophage applied), significantly improving water quality. The phage can effectively inhibit the propagation of Nocardia in the actual sludge-foaming event, control the sludge foaming, and improve the effluent quality. It provides a novel and relatively economical solution for controlling sludge foaming in sewage treatment plants in the future, shows that the phages have potential application value in the prevention and control of Nocardia, and provides another way to control the sludge-foaming event caused by the excessive reproduction of Nocardia in the future.

Measurements of Methane Emissions from a Biofertilizer Storage Tank Using Ground-Based Hyperspectral Imaging and Flux Chambers.

Open storages of organic material represent potentially large sources of the greenhouse gas methane (CH4), an emissions source that will likely become more common as a part of societal efforts toward sustainability. Hence, monitoring and minimizing CH4 emissions from such facilities are key, but effective assessment of emissions without disturbing the flux is challenging. We demonstrate the capacity of using a novel high-resolution hyperspectral camera to perform sensitive CH4 flux assessments at such facilities, using as a test case a biofertilizer storage tank for residual material from a biogas plant. The camera and simultaneous conventional flux chamber measurements showed emissions of 6.0 ± 1.3 and 13 ± 5.7 kg of CH4 h-1, respectively. The camera measurements covered the whole tank surface of 1104 m2, and the chamber results were extrapolated from measurements over 5 m2. This corresponds to 0.7-1.4% of the total CH4 production at the biogas plant (1330 N m3 h-1 corresponding to 950 kg h-1). The camera could assess the entire tank emission in minutes without disturbing normal operations at the plant and revealed additional unknown emissions from the inlet to the tank (17 g of CH4 h-1) and during the loading of the biofertilizer into trucks (3.1 kg of CH4 h-1 during loading events). This study illustrates the importance of adequate measurement capacity to map methane fluxes and to verify that methane emission mitigation efforts are effective. Given the high methane emissions observed, it is important to reduce methane emissions from open storage of organic material, for example by improved digestion in the biogas reactor, precooling of sludge before storage, or building gastight storage tanks with sealed covers. We conclude that hyperspectral, ground-based remote sensing is a promising approach for greenhouse gas monitoring and mitigation.

Foam Segmentation in Wastewater Treatment Plants

The excessive accumulation of foam in wastewater treatment plant (WWTP) tanks can impede proper aeration, hindering the effective removal of organic matter from the water. This study proposes a novel technique to monitor in real time the presence of foams in WWTP tanks by using texture segmentation models trained with centralized and federated approaches. These models are designed to segment the foam and quantify the percentage of foam coverage across the entire tank surface. This data provides plant operators with crucial information for identifying the optimal time for foam removal. The proposed methodology is integrated into an image processing pipeline that involves acquiring images using a PTZ camera, ensuring the absence of anomalies in the captured images, and implementing a real-time communication method for event notifications to plant operators. The models exhibit noteworthy performance, achieving an 86% Dice score in foam segmentation, with comparable results obtained through both centralized and federated training. Implemented in a wastewater treatment plant, this integrated pipeline enhances operational efficiency while concurrently reducing costs.