scholarly journals Alternative Use of Artificial Quarry Lakes as a Source of Thermal Energy for Greenhouses

Water ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 3560
Author(s):  
Jessica Maria Chicco ◽  
Felix-Antoine Comeau ◽  
Alessandro Casasso ◽  
Cesare Comina ◽  
Nicolò Giordano ◽  
...  
Keyword(s):  
Thermal Energy ◽  
Operating Costs ◽  
Heat Extraction ◽  
Mixing Process ◽  
Large Lake ◽  
Qualitative Comparison ◽  
Groundwater Systems ◽  
Different Depths ◽  
Nw Italy ◽  
Definition Of

In northern Italy, most greenhouses rely on gas or oil heaters which are sometimes subject to high operating costs. Several greenhouses are nearby quarry lakes, which are the legacy of the expansion of cities in the last decades, including Turin (NW Italy). About 20 quarry lakes were excavated close to the Po riverbed in the southern part of this urban area, along a belt of more than 30 km in length, with an overall volume exceeding 10 million m3 water. The study addresses these artificial lakes as a low enthalpy thermal energy source, potentially providing heat to surrounding agri-business buildings. Detailed temperature monitoring of a large lake quarry was conducted over two years at different depths, measuring the surrounding groundwater level as well. Two different behaviors of the lake during the winter and summer seasons enabled the definition of a quite low water mixing process between the surrounding aquifers and the lake (in the range of 2–4 °C). An evaluation of the heat extraction potential using the lake as a heat source, depending on water temperature and its volume, and a qualitative comparison with groundwater systems are proposed. This study contributes to increasing knowledge on an overlooked resource for sustainable heating.

scholarly journals Empirical Validation and Numerical Predictions of an Industrial Borehole Thermal Energy Storage System

Energies ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 2263
Author(s):  
Emil Nilsson ◽  
Patrik Rohdin
Keyword(s):  
Energy Storage ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Large Scale ◽  
Storage System ◽  
Flow Characteristics ◽  
Heat Extraction ◽  
Short Term ◽  
Numerical Predictions ◽  
Heat Injection

To generate performance predictions of borehole thermal energy storage (BTES) systems for both seasonal and short-term storage of industrial excess heat, e.g., from high to low production hours, models are needed that can handle the short-term effects. In this study, the first and largest industrial BTES in Sweden, applying intermittent heat injection and extraction down to half-day intervals, was modelled in the IDA ICE 4.8 environment and compared to three years of measured storage performance. The model was then used in a parametric study to investigate the change in performance of the storage from e.g., borehole spacing and storage supply flow characteristics at heat injection. For the three-year comparison, predicted and measured values for total injected and extracted energy differed by less than 1% and 3%, respectively and the mean relative difference for the storage temperatures was 4%, showing that the performance of large-scale BTES with intermittent heat injection and extraction can be predicted with high accuracy. At the actual temperature of the supply flow during heat injection, 40 °C, heat extraction would not exceed approximately 100 MWh/year for any investigated borehole spacing, 1–8 m. However, when the temperature of the supply flow was increased to 60–80 °C, 1400–3100 MWh/year, also dependent on the flow rate, could be extracted at the spacing yielding the highest heat extraction, which in all cases was 3–4 m.

The potential for thermal energy recovery from wastewater treatment works in southern England

2012 ◽  
Vol 3 (4) ◽  
pp. 287-299 ◽  
Author(s):  
Christopher Hawley ◽  
Richard Fenner
Keyword(s):  
Wastewater Treatment ◽  
Carbon Footprint ◽  
Thermal Energy ◽  
Energy Recovery ◽  
Shadow Price ◽  
Economic Feasibility ◽  
Heat Extraction ◽  
Southern England ◽  
Financial Feasibility ◽  
Discharge Temperature

This paper asks how much heat could be recovered from wastewater treatment plants under UK climatic conditions, and can this heat be used effectively to reduce their carbon footprint? Four wastewater treatment sites in southern England have been investigated and the available heat quantified. Issues relating to the environmental, economic and practical constraints on how this energy can be realistically recovered and utilised are discussed. The results show there is a definite possibility for thermal energy recovery and demonstrates that the financial feasibility of three options for using the heat (either for district heating, sludge drying or thermophilic heating in sludge digestion processes) is highly dependent upon the current shadow price of carbon. Without the inclusion of the cost of carbon, the financial feasibility is significantly limited. An environmental constraint for the allowable discharge temperature of effluent after heat extraction was found to be the major limitation to the amount of energy available for recovery. The paper establishes the true potential of thermal energy recovery from wastewater in English conditions and the economic feasibility of reducing the carbon footprint of wastewater treatment operations using this approach.

scholarly journals RESULTS OF TESTS ON THE STALK AND GRAIN CRUSHER OF A SMALL FODDER SHOP

2020 ◽  
Vol 55 (1) ◽  
pp. 25-30
Author(s):  
Abilzhanuly T. ◽  
Abilzhanov D.T. ◽  
Smagulov T.A. ◽  
Orazakhyn D.N.
Keyword(s):  
Power Consumption ◽  
Technological Innovation ◽  
Dairy Farms ◽  
Scientific Production ◽  
Operating Costs ◽  
Mixing Process ◽  
Small Farms ◽  
3.0 T ◽  
Combined Feed ◽  
Nutrient Feed

It is known that in Kazakhstan, 70 ... 80 percent of peasant farms have no more than 100 head of cattle and 500 head of sheep. To fatten these farms and to prepare a complete ration with combined feed in dairy farms, a distributer-mixer with a box with a capacity of 3 ... 5 m3 is needed. Since the equipment of these distributer-mixer machines with stalk and grain crushers ensures that it chops fodder itself and loads them onto a hay rye and grain warehouse of a mobile fodder shop, in the process of preparing a full ration of a combined feed, the number of operations will be reduced by 1.67 times, and the operating costs of the unit will be reduced by 1.5 times. In addition, if the stalk fodder is crushed by zootechnical requirements, i.e. 30 to 50 mm, then the uniformity of the mixing process increases. Here you can mix with the addition of nutrient feed in the preparation of the combined feed, that is, the use of a mobile fodder shop in the household allows you to carry out the process of preparing a combined feed using new and inexpensive technologies, i.e. the use of a mobile fodder shop equipped with special crushers is a technological innovation. At present, the “Scientific Production Center of Agroengineering” on small farms is developing a mobile fodder shop for the preparation and distribution of compound feeds with a capacity of 5.0 m3, equipped with crushers for stalk and croup. In addition, in order to simplify the drive to the crusher and to make the design simple, the crusher of the stalk and grain are equipped with one bucket, that is, this is a technical novelty of the mobile fodder shop. Stalk and grain crushers of mobile fodder shops were made and tested. During the tests, the productivity of the stalk chopper is 2.5 ... 3.0 t/h, the power consumption is 6.2...7.0 kW, and the productivity of the grain crusher is 750 - 900 kg/h, and it was found that the power consumption in the performance range will be between 5.1 ... 7.2 kW. It was proved that the size of the crushed stalk and grain meets zootechnical requirements.

Effect of Rainfall Infiltration on Loess Pitted Courtyard Cave Dwellings Stability

2012 ◽  
Vol 430-432 ◽  
pp. 1992-1995 ◽  
Author(s):  
Jia Ming Han ◽  
San Qing Su
Keyword(s):  
Water Content ◽  
Safety Factor ◽  
Triaxial Test ◽  
Field Measurements ◽  
Surrounding Rock ◽  
Rainfall Infiltration ◽  
Mechanical Parameter ◽  
Different Depths ◽  
Definition Of ◽  
The Relationship

Baishe villagers have inhabited loess pitted courtyard cave dwelling for hundreds of years in Sanyuan County of China.The sizes of local cave dwellings are mastered by field measurements, and variational regularity is summarized of average annual and monthly rainfall. By the soil routine and triaxial test, the physical and mechanical parameter is acquired with loess samples in different water content.At the same time, based on the literature datas, the relationship is established between rainfall and water content. Then, the definition of safety factor is given for loess cave dwellings in different depths, making use of the expressions of the surrounding rock loop stress and the Mohr - Coulomb intensity criterion. In the end,the variation of stability of loess cave dwelling could be analysed under different rainfall.

Thermohydraulic Analysis of Ground as a Heat Source for Heat Pumps Using Vertical Pipes

1996 ◽  
Vol 118 (4) ◽  
pp. 300-305 ◽  
Author(s):  
M. T. Kangas
Keyword(s):  
Computer Simulation ◽  
Heat Source ◽  
Heat Pump ◽  
Thermal Energy ◽  
System Performance ◽  
Thermal Effects ◽  
Heat Pumps ◽  
The Other ◽  
Heat Extraction ◽  
Energy Potential

In this study, the use of the ground as the heat source for a heat pump was studied by computer simulation. The heat extraction system consisted of vertical pipes drilled into the ground where groundwater was present. Along with available thermal energy, potential environmental effects, such as freezing and thermal pollution, were examined. It was found that the presence of groundwater enhances system performance by decreasing the possibility of freezing but, on the other hand, increases the range of thermal effects in the ground. The temperature of the ground as well as extraction arrangements also have a significant effect on system performance.

Research of Engine Performance Control Based on EGTM

2011 ◽  
Vol 148-149 ◽  
pp. 431-436
Author(s):  
Hong Bo Peng ◽  
Min Dan
Keyword(s):  
Condition Monitoring ◽  
Life Prediction ◽  
Great Influence ◽  
Engine Performance ◽  
Operating Costs ◽  
Estimation Methods ◽  
Performance Control ◽  
Definition Of ◽  
Engine Condition ◽  
Engine Life

Life prediction is one important of Engine research. Take-off EGTM is an important parameter to monitor Engine performance. Take-off EGTM have great influence on Engine life, Reducing EGT will help to extend Engine life on wing (LOW), thereby reducing operating costs. Aiming at Engine condition monitoring, the definition of take-off EGT Margin is given, estimation methods and their application on Engine life prediction are discussed.

THE DIURNAL ACTIVITY OF THE LARGER INVERTEBRATES AT THE SURFACE OF LAC LA RONGE, SASKATCHEWAN

1959 ◽  
Vol 37 (6) ◽  
pp. 945-956 ◽  
Author(s):  
J. H. Mundie
Keyword(s):  
Hyalella Azteca ◽  
Diurnal Activity ◽  
Large Lake ◽  
Mysis Relicta ◽  
Chironomid Larvae ◽  
The Hours ◽  
Chironomid Midges ◽  
Different Depths ◽  
Benthic Animals

Horizontal hauls were made with a pair of large plankton nets at the surface of a large lake to determine the 24-hour emergence cycle of chironomid midges rising from different depths and to investigate the occurrence of the larger invertebrates at the surface. Chironomid pupae ascend mainly in the hours of darkness and emergence may be immediate, as in Psilotanypus rufovittatus, or delayed for several hours, as in Procladius choreus. A migration to the surface at night is demonstrated for Mysis relicta and the amphipods Pontoporeia affinis and Hyalella azteca. Chironomid larvae and a variety of other invertebrates also occur at the surface. The findings show that many benthic animals are less static in their distribution than is commonly accepted.

scholarly journals Selection of low temperature thermal power cycles

2020 ◽  
pp. 165-165
Author(s):  
Mukundjee Pandey ◽  
Biranchi Padhi ◽  
Ipsita Mishra
Keyword(s):  
Low Temperature ◽  
Thermal Energy ◽  
High Efficiency ◽  
Thermal Power ◽  
Organic Rankine Cycle ◽  
Operating Conditions ◽  
Solar Thermal ◽  
Heat Extraction ◽  
Solar Thermal Energy ◽  
Kalina Cycle

In today?s world, we are facing the problem of fossil fuel depletion along with its cost continuously increasing. Also, it is getting difficult to live in a pollution free environment. Solar energy is one of the most abundantly and freely available form of energy. Out of the various ways to harness solar en-ergy, solar thermal energy is the most efficient as compared to photo-voltaic technology. There are various cycles to convert the solar thermal energy to mechanical work, but Kalina cycle (KC) is one of the best candidates for high efficiency considerations. Therefore, the authors have proposed a novel KC having the double separator arrangements to increase the amount of ammonia vapors at the inlet of turbine, and hence have tried to minimize the pumping power for Double Separator Kalina Cycle (DS-KC) by reducing the fraction of gas/vapors through it. Here, in this paper we have tried to com-pare Organic Rankine Cycle (ORC), Brayton Cycle (BC) and Double Sepa-rator Kalina Cycle (DS-KC) for low temperature heat extraction from para-bolic trough collectors having arc-circular plug with slits (PTC). The effect of different operating conditions; like the number of PTCs, mass flow rate of fluids in different cycles, pressure difference in turbine are analyzed. The ef-fect of these different operating conditions on different parameters like net work done, heat lost by condenser, thermal efficiency and installation cost per unit kW for DS-KC, ORC and BC are studied.

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