scholarly journals Innovative Low-Cost Naturally Ventilated Maize Seed Storage System

2021 ◽  
pp. 39-49
Author(s):  
Siphiwe Mdlalose ◽  
Sipho Sibanda ◽  
Tilahun Workneh ◽  
Mark Laing

A 22-m3 residential room was converted to a seed storage facility by retrofitting a solar collector on the roof. Three different chimney sizes of diameter and height of 200 mm x 3.6 m, 200 mm x 4.8 m, 300 mm x 3.6 m, and 300 mm x 4.8 m were investigated to determine the best size of the chimney to be used for ventilation in a storage facility. The parameters measured were the air velocity in the chimney duct, as well as the air temperature and relative humidity at the inlet, centre, and outlet of the storage facility. The diameter of the chimney had a significant effect (P<0.05) on the ventilation rate achieved in the storage facility. Significant differences were found between the different chimney diameters and heights (P≤0.05). The 300 mm diameter chimneys were able to extract hot air from the roof solar collector; however, the 200 mm diameter failed. The modified naturally-ventilated seed storage room was able to reduce the relative humidity from 69.7% to a safe relative humidity of 37.9%, while at the same time the temperature increased from 23.3℃ to 35℃ in the 300 mm x 4.8 m chimney.

Author(s):  
Jinhua Wang ◽  
Bing Wang ◽  
Bin Wu ◽  
Yue Li

There are more than 400 reactors in operation to generate electricity in the world, most of them are pressurized water reactors and boiling water reactors, which generate great amount of spent fuel every year. The residual heat power of the spent fuel just discharged from the reactor core is high, it is required to store the spent fuel in the spent fuel storage pool at the first 5 years after discharged from the reactor, and then the spent fuel could be moved to the interim storage facility for long term storage, or be moved to the factory for final treatment. In the accident of the Fukushima in 2011, the spent fuel pool ruptured, which led to the loss of coolant accident, it was very danger to the spent fuel assemblies stored in the pool. On the other hand, the spent fuel stored in the dry storage facility was safe in the whole process of earthquake and tsunami, which proved inherent safety of the spent fuel dry storage facility. In china, the High Temperature gas cooled Reactor (HTR) is developing for a long time in support of the government. At the first stage, HTR-10 with 10MW thermal power was designed and constructed in the Institute of Nuclear Energy Technology (INET) of Tsinghua University, and then the High Temperature Reactor-Pebble bed Modules (HTR-PM) is designed to meet the commercial application, which is in constructing process in Shandong Province. HTR has some features of the generation four nuclear power plant, including inherent safety, avoiding nuclear proliferation, could generate high temperature industrial heat, and so on. Spherical fuel elements would be used as fuel in HTR-PM, there are many coating fuel particles separated in the fuel element. As the fuel is different for the HTR and the PWR, the fuel element would be discharged into the appropriate spent fuel canister, and the canister would be stored in the appropriate interim storage facility. As the residual power density is very low for the spent fuel of HTR, the spent fuel canister could be cooled with air ventilation without water cooling process. The advantage of air cooling mode is that it is no need to consider the residual heat removal depravation due to loss of coolant accident, so as to increase the inherent safety of the spent fuel storage system. This paper introduced the design, arrangement and safety characteristics of the spent fuel storage well of HTR-PM. The spent fuel storage wells have enough capacity to hold the total spent fuel canisters for the HTR-PM. The spent fuel storage facility includes several storage wells, cold intake cabin, hot air discharge cabin, heat shield cylinders, well lids and so on. The cold intake cabin links the inlets of all the wells, which would be used to import cold air to every well. The hot air discharge cabin links the outlets of all the wells, which would be used to gather heated air discharged from every well, the heated air would be discharged to the atmosphere through the ventilating pipe at the top of the hot air cabin. The design of the spent fuel storage well and the ventilating pipe could discharge the residual heat of the spent fuel canisters in the storage wells, which could ensure the operating safety of the spent fuel storage system.


2021 ◽  
Vol 21 (07) ◽  
pp. 18368-18390
Author(s):  
Sipho Sibanda ◽  
◽  
S Mdlalose ◽  
T Workneh ◽  
M Laing ◽  
...  

The performance of a solar energy-assisted seed storage room was evaluated through an ordinary 22-m3 room that was retrofitted with a solar collector, inlets and chimney. The structure was made of a solar collector to heat the ambient air before entering the chimney. The chimney circulated the air inside the structure and inlets. To compare the performance of the modified storage room, a room with a similar capacity and without the retrofitted components (control storage room) was used. Twelve 8 kg bags of maize were stored in each storage room for a period of three months. Samples were taken every two weeks to determine germination rate, moisture content and seed vigour. The temperature and relative humidity (RH) was measured during storage. The RH in the control storage was significantly higher (P≤0.05) (60.6 ± 5.87%) than in the modified storage (40.1 ± 3.21%) during the day. However, at night, the RH in the control storage room was significantly lower (P≤0.05) (58.5 ± 7.32%) than in the modified storage (63.7 ± 6.28%). The RH in the modified storage room increased from 40.1% during the day to 63.7% at night. The RH in the control storage room decreased slightly from 60.6% to 58.5% during the day and night. The seed moisture content in the modified storage facility was significantly lower (P≤0.05) (12.6 ± 0.21%) than in the control storage room (13.3 ± 0.52%). The moisture content in the modified storage room decreased from 12.6% to 12.4%, whereas in the control room, moisture content increased from 12.6% to 13.8% in three months. The seed germination rate obtained after three months of storage in the modified storage room was significantly higher (P≤0.05) (98.5 ± 0.85%) than in the control storage room (96.8 ± 1.49%).The seed vigour obtained in the modified storage room was significantly higher (93.6 ± 0.35%) than in the control room (91.7 ± 2.08%) (P≤0.05). Seed stored in the control storage lost vigour at a faster rate, compared to the seeds stored in the modified storage room. Therefore, the modified naturally-ventilated seed storage room maintained seed quality better than the control storage room.


2011 ◽  
Vol 121-126 ◽  
pp. 2011-2015
Author(s):  
Yuttachai Keawsuntia ◽  
Cheevin Limsiri ◽  
Thamrong Prempridi ◽  
Sanguan Patamatamkul

Solar updraft tower is an alternative technology for electricity generating from solar energy. It’s suitable for use in remote area, where there is high potential of solar radiation, because the constructions are cheap and the technologies involved are conventional. From the study of small scale solar updraft tower by using the computation fluid dynamics program and experimental, show that the hot air velocity in the solar updraft tower from the computation fluid dynamics program similarly with the experimental data. From this study, the small-scale solar updraft tower with 72 m length in each side of solar collector, air inlet height of 0.5 m above the ground, an updraft tower of 30 meter high with 1.2 m length of each side was studied to determine the performance. It was found that the electricity generating from this model was 6893 W/day, enough to supply electricity for up to 13 families of small community in the rural area.


2019 ◽  
Vol 12 (1) ◽  
pp. 12-21
Author(s):  
Feby Nopriandy ◽  
Suhendra Suhendra

Abstrak. Metode pengeringan menggunakan surya sebagai sumber energi panas adalah metode pengeringan yang banyak digunakan. Besarnya panas yang dihasilkan tergantung dari jumlah radiasi matahari yang dapat ditangkap oleh kolektor surya. Tangkapan radiasi matahari dapat dioptimalkan dengan merekayasa kolektor surya yang dapat bergerak mengikuti posisi matahari. Kualitas produk pangan yang dikeringkan sangat dipengaruhi oleh aliran udara panas pada proses pengeringan. Berdasarkan permasalahan tersebut, perlu dilakukan kajian tentang aliran udara panas pada kolektor surya yang bergerak mengikuti posisi matahari. Penelitian menggunakan 2 buah kolektor surya yang direkayasa dengan ukuran, bentuk dan bahan yang sama dimana salah satu kolektor berada dalam kondisi tetap dan kolektor lainnya dapat bergerak mengikuti posisi matahari. Kecepatan aliran udara panas yang keluar dari saluran keluar (outlet) kolektor surya divariasikan menjadi 3 perlakuan yaitu 2 m/s, 4 m/s dan 6 m/s. Pengambilan data dimulai dari pukul 08.00 sampai pukul 16.00 dengan selang waktu pengambilan data adalah setiap 30 menit. Hasil analisis menunjukkan bahwa kecepatan udara panas pada outlet kolektor surya sangat berbeda nyata pengaruhnya terhadap nilai temperatur udara panas di dalam dan outlet kolektor surya. Kolektor surya yang bergerak mengikuti posisi matahari dapat meningkatkan performansi temperatur di dalam dan outlet kolektor surya pada berbagai kondisi kecepatan udara outlet berbanding kolektor surya tetap. Kenaikan performansi tertinggi di dalam dan outlet kolektor surya diperoleh pada kecepatan udara outlet 2 m/s masing-masing sebesar 16,29% dan 3,98%.  Analysis of Fluid Flow Speed on Solar Collector Performance which Moves to follow the Position of the Sun Abstract. The drying method using solar as a source of heat energy is a widely used drying method. The amount of heat produced depends on the amount of solar radiation that can be collected by solar collector. The capture of solar radiation can be optimized by construction the solar collector that can move in the sun's position. The quality of dried food products is strongly influenced by the flow of hot air in the drying process. Based on these problems, it is necessary to study the flow of hot air in solar collectors that move in the sun's position. The study used 2 units of solar collector that construction with the same size, shape and material where one of the collectors is in a fixed condition and the other collector can move in the sun's position. The velocity of hot air flowing out of the outlet of the solar collector was varied into 3 treatments, namely 2 m/s, 4 m/s and 6 m/s. Data collection starts at 8:00 a.m. until 16:00 p.m. with an interval of data collection is every 30 minutes. The results of the analysis show that the hot air velocity at the solar collector outlet has a very different effect on the temperature value of hot air inside and the solar collector outlet. Solar collector that move in the sun's position can increase the temperature performance in and solar collector outlets in various conditions of outlet air velocity. The highest increase in performance in and solar collector outlets was obtained at outlet air velocity of 2 m / s at 16.29% and 3.98% respectively.


2021 ◽  
Author(s):  
Vikram M. Patel

With the closing of the Yucca mountain storage facility, on-site storage of spent nuclear fuel at reactor sites has increased and will continue to increase until a permanent storage facility is prepared. Dry storage canisters are used to store spent nuclear fuel waste over long periods of time, but are susceptible to mechanical failure via corrosion. This dissertation presents a system to monitor the integrity of the storage canister. Sensor data fusion algorithms have been designed to predict the integrity of the storage system and provide feedback for preventative maintenance. The environmental conditions that lead to corrosion have been replicated and detected by the sensor system within an environmental chamber and the predictive model has been able to estimate the time till failure of a sacrificial corrosion sensor.


2003 ◽  
Vol 3 (4) ◽  
pp. 169-175 ◽  
Author(s):  
S. Barbagallo ◽  
F. Brissaud ◽  
G.L. Cirelli ◽  
S. Consoli ◽  
P. Xu

In arid and semiarid regions the reclamation and reuse of municipal wastewater can play a strategic role in alleviating water resources shortages. Public awareness is growing about the need to recycle and reuse water for increasing supply availability. Many wastewater reuse projects have been put in operation in European and Mediterranean countries adopting extensive treatment systems such as aquifer recharge, lagooning, constructed wetlands, and storage reservoirs, mainly for landscape and agricultural irrigation. In agricultural reuse systems, there is an increasing interest in extensive technologies because of their high reliability, and easy and low cost operation and maintenance. Wastewater storage reservoirs have become the option selected in many countries because of the advantages they present in comparison with other treatment alternatives, namely the coupling of two purposes, stabilization and seasonal regulation. This paper describes an example of a wastewater storage system, built in Caltagirone (Sicily, Italy). The storage results in a tertiary treatment of a continuous inlet flow of activated sludge effluents. The prediction of the microbiological water quality has been evaluated by means of a non-steady-state first-order kinetic model. Single and multiple regressions were applied to determine the main variables that most significantly affected die-off coefficients. The proposed model has been calibrated using the results of a field monitoring carried out during a period from March to October 2000.


Toxics ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 140
Author(s):  
Francesca Borghi ◽  
Andrea Spinazzè ◽  
Simone Mandaglio ◽  
Giacomo Fanti ◽  
Davide Campagnolo ◽  
...  

Recently, the need to assess personal exposure in different micro-environments has been highlighted. Further, estimating the inhaled dose of pollutants is considerably one of the most interesting parameters to be explored to complete the fundamental information obtained through exposure assessment, especially if associated with a dose-response approach. To analyze the main results obtained from the studies related to the estimation of the inhaled dose of pollutants in different micro-environments (environments in which an individual spends a part of his day), and to identify the influence of different parameters on it, a systematic review of the literature was performed. The principal outcomes from the considered studies outlined that (i) exposure concentration and residence time are among the most important parameters to be evaluated in the estimation of the inhaled dose, especially in transport environments. Further, (ii) the pulmonary ventilation rate can be of particular interest during active commuting because of its increase, which increases the inhalation of pollutants. From a methodological point of view, the advent of increasingly miniaturized, portable and low-cost technologies could favor these kinds of studies, both for the measurement of atmospheric pollutants and the real-time evaluation of physiological parameters used for estimation of the inhaled dose. The main results of this review also show some knowledge gaps. In particular, numerous studies have been conducted for the evaluation (in terms of personal exposure and estimation of the inhaled dose) of different PM fractions: other airborne pollutants, although harmful to human health, are less represented in studies of this type: for this reason, future studies should be conducted, also considering other air pollutants, not neglecting the assessment of exposure to PM. Moreover, many studies have been conducted indoors, where the population spends most of their daily time. However, it has been highlighted how particular environments, even if characterized by a shorter residence time, can contribute significantly to the dose of inhaled pollutants. These environments are, therefore, of particular importance and should be better evaluated in future studies, as well as occupational environments, where the work results in a high pulmonary ventilation rate. The attention of future studies should also be focused on these categories of subjects and occupational studies.


2021 ◽  
Author(s):  
Mervette El Batouti ◽  
H. A. Fetouh

New ferroelectric perovskite sample: excellent dielectric, negligible dielectric loss for energy storage systems such as solar cells, solar ponds, and thermal collectors has been prepared at low cost using nanotechnology.


Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1202
Author(s):  
Miguel Tradacete ◽  
Carlos Santos ◽  
José A. Jiménez ◽  
Fco Javier Rodríguez ◽  
Pedro Martín ◽  
...  

This paper describes a practical approach to the transformation of Base Transceiver Stations (BTSs) into scalable and controllable DC Microgrids in which an energy management system (EMS) is developed to maximize the economic benefit. The EMS strategy focuses on efficiently managing a Battery Energy Storage System (BESS) along with photovoltaic (PV) energy generation, and non-critical load-shedding. The EMS collects data such as real-time energy consumption and generation, and environmental parameters such as temperature, wind speed and irradiance, using a smart sensing strategy whereby measurements can be recorded and computing can be performed both locally and in the cloud. Within the Spanish electricity market and applying a two-tariff pricing, annual savings per installed battery power of 16.8 euros/kW are achieved. The system has the advantage that it can be applied to both new and existing installations, providing a two-way connection to the electricity grid, PV generation, smart measurement systems and the necessary management software. All these functions are integrated in a flexible and low cost HW/SW architecture. Finally, the whole system is validated through real tests carried out on a pilot plant and under different weather conditions.


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