Hot Water Plant Research Articles

Simulation of Thermal Pollution at Tigris River due to Al- Dora Power Plant

Thermal water pollution is a cost saving in cooling process for the electrical industry but it has negative effect on environment. When thermal water is released from power plants into water bodies, it is harmful to marine life. High temperature reduces aerobic decomposition. As organic matter degrades, the amount of nutrients in water bodies is diminished. The study propose a solution to reduce the thermal effect of plant water using the CFD comsol software. The results shows that a change in the width of the channel of the plant hot water to 10 m reduce the thermal effect of the hot water plant, which leads to less environmental effect.

Analysis of the integration of micro-cogeneration units in space heating and domestic hot water plants

Micro-cogeneration has been recognized as an efficient technology that can contribute to European Union’s energy and climate objectives with respect to delivering low-carbon heat and power to citizens and small businesses. For improving the performance of this technology and so take as much advantage as possible of its potential, thermal energy storage plays a key role. This paper presents a techno-economic evaluation and optimization procedure focused on properly sizing and designing a micro-cogeneration residential installation, emphasizing how thermal energy storage is arranged and the different thermal loads prioritized within the plant. Therefore, the proposed methodology can be easily applied to buildings with different conditions and constraints.The methodology is then applied to a representative case study that consists of a detached house with a 1 kWe micro-cogeneration plant. Results of the case study show that in small installations DHW accumulation does not provide any significant improvement but a worsening of efficiency. Additionally, it is also proved that the layout of the distribution loop has an importance on the final performance of the plant that must be kept in mind. Moreover, results show that TES systems coupled with micro-cogeneration engines are traditionally highly oversized, thus worsening economic viability of these facilities.

Comparison of Anolyte and Chlorine Dioxide for a Continuous Hot Water Disinfection in Nursing Home: A Two Years Legionnaires’ Disease Prevention

Worldwide epidemiological reports assert that drinking water is a source for infections and Legionella control represents a critical issue in healthcare settings. Chemical disinfections of water networks are control measures that need to be fine-tuned to obtain satisfactory results in large buildings over prolonged time periods. Aim of study is the evaluation of the effect of anolyte and chlorine dioxide, applied in two different hot water networks of a nursing home to manage Legionella risk. Nursing home has two buildings (A and B), with the same point of aqueduct water entrance. From June 2016, following a shock chlorination, the continuous disinfections with chlorine dioxide and anolyte were applied in hot networks of building A and B, respectively. Hot water was sampled at the central heating system and at two points of use for Legionella research, while chemical tests of manganese (Mn), iron (Fe), zinc (Zn) and trihalomethanes compounds (THM) were implemented to evaluate the disinfection by-products presence. Before chlorination Legionella pneumophila sg1 was recovered with a mean count of 2.4 × 104 CFU/L, while chemical compounds concentrations were within the law limits (Directive 98/83/EC). Then the disinfections Legionella was not recovered in both hot water plants. After the disinfection with chlorine dioxide (from June 2016 to May 2018), a statistically significant increase of iron, zinc and THM concentrations was detected in building A (p = 0.012; p = 0.004; p = 0.008). Both disinfectants appear effective against Legionella spp. growth in water network, but anolyte ensures a lower disinfection by-products release.

Beneficial Effects of Lemon Balm Leaf Extract on In Vitro Glycation of Proteins, Arterial Stiffness, and Skin Elasticity in Healthy Adults.

Glycation, a non-enzymatic glycosylation of proteins, induces tissue damage in association with various diseases and aging phenomena. Pentosidine, an advanced glycation end product, is involved in aging phenomena such as tissue stiffness. In this study, we aimed to find a potent anti-glycation food material and to verify its health benefits by clinical trial. From among 681 hot water plant extracts, lemon balm (Melissa officinalis; LB) leaf extract was selected and revealed to have more potent inhibitory activity for pentosidine formation than a representative anti-glycation agent, aminoguanidine. Rosmarinic acid (RA), a typical polyphenol in Lamiaceae plants, was identified as a major active component in LB extract (LBE). Furthermore, LBE or RA dose-dependently suppressed glycation-associated reactions such as increased fluorescence, yellowing of collagen fiber sheets, and degeneration of the fibrous structure of elastin fiber sheets. An open-label, parallel-group comparative trial was conducted in 28 healthy Japanese subjects aged 31-65 y who consumed LB tea (LB group) or barley tea (Control group) for 6 wk. The LB group showed significant reductions in brachial-ankle pulse wave velocity, reflecting arterial stiffness, and b* (yellow) color values in forearm skin compared with the Control group. A gender-stratified analysis revealed that cheek skin elasticity was significantly improved in the LB group compared with the Control group only in female subjects. It is concluded that the hot water extract of LB leaf has the potential to provide health benefits with regard to glycation-associated tissue damage in blood vessels and skin of healthy adults.

Evaluation and Parametric Optimization of the Thermal Performance and Cost Effectiveness of Active-Indirect Solar Hot Water Plants

Evaluation and Parametric Optimization of the Thermal Performance and Cost Effectiveness of Active-Indirect Solar Hot Water Plants

The influence of biomass quality on the stability and sustainability of district heating systems of low-accumulation objects

Original scientific paper Research was conducted during the incineration of six different biomass groups, whereat each group was observed for three cases of average initial moisture level for the purpose of quantifying the values of impact parameters and contribution to the correlation between biomass quality and the efficiency of a thermal power system. A hot water plant with the power to heat ratio amounting to Q = 600 kW was used, which included a district heating system of a low-accumulation object with a low thermophysical constant and a low time constant. Research was conducted in 18 equal cycles at low outside air temperatures and a maximum need for useful thermal energy. Quantified values showed the consumption of all groups of all average moisture levels of biomass. By analysing the examined temperature of a heating medium and flue gases during the combustion of each biomass group, a direct influence of its quality and average moisture on the sustainability and stability of the district heating system was shown. The most favourable biomass was proposed. Direct application of research results contributes to correct determination of the type, composition and average moisture of biomass, as well as a higher efficiency of the whole thermal power system.

In vitro antifungal activity and probable fungicidal mechanism of aqueous extract of Barleria grandiflora.

Barleria grandiflora Dalz. (Acanthaceae) is being used in India to treat different types of disorders including skin infections. Therefore, there are good possibilities to find antifungal compounds in its extracts with novel mechanism of action. The main objectives of the present study were to evaluate the antifungal activity of plant extracts and to study its effects on metabolic pathways of A. fumigatus. The microbroth dilution assay was used to explore antifungal activity and MIC of various extracts. Metabolic profiles of control and treated cultures were collected from Q-TOF-MS interfaced with HPLC. Affected metabolic pathways of A. fumigatus after the treatment were analyzed by discrimination analysis of mass data. Antifungal activities were observed in hot and cold water extracts of the plant. Hot water extract of B. grandiflora showed significant activity against tested fungi in the range 0.625-1.25 mg/mL. Partial least discrimination analysis revealed that the hot water plant extract downregulated amino acid, glyoxylate pathway, and methylcitrate pathways at the same time due to the synergistic effects of secondary metabolites. Hot water extract also downregulated several other metabolic pathways unique to fungi indicating its specific activity toward fungi. B. grandiflora showed promising antifungal activity which can further be exploited by identification of active compounds, to inhibit the specific fungal pathways and development of novel therapeutic antifungal drugs.

Thermal analysis and performance optimization of a solar hot water plant with economic evaluation

The main objective of this study is to optimize the long-term performance of an existing active-indirect solar hot water plant (SHWP), which supplies hot water at 65°C for use in a flight kitchen, using a micro genetic algorithm in conjunction with a relatively detailed model of each component in the plant and solar radiation model based on the measured data. The performance of SHWP at Changi International Airport Services (CIASs), Singapore, is studied for better payback period using the monthly average hourly diffuse and beam radiations and ambient temperature data. The data input for solar radiation model is obtained from the Singapore Meteorological Service (SMS), and these data have been compared with long-term average data of NASA (surface meteorology and solar energy or SSE). The comparison shows a good agreement between the predicted and measured hourly-averaged, horizontal global radiation.The SHWP at CIAS, which comprises 1200m2 of evacuated-tube collectors, 50m3 water storage tanks and a gas-fired auxiliary boiler, is first analyzed using a baseline configuration, i.e., (i) the local solar insolation input, (ii) a coolant flow rate through the headers of collector based on ASHRAE standards, (iii) a thermal load demand pattern amounting to 100m3/day, and (iv) the augmentation of water temperature by auxiliary when the supply temperature from solar tank drops below the set point. A comparison between the baseline configuration and the measured performance of CIAS plant gives reasonably good validation of the simulation code. Optimization is further carried out for the following parameters, namely; (i) total collector area of the plant, (ii) storage volume, and (iii) three daily thermal demands. These studies are performed for both the CIAS plant and a slightly modified plant where the hot water supply to the load is adjusted constant at times when the water temperature from tank may exceed the set temperature. It is found that the latter configuration has better thermal and economic performances over the conventional design.

Laboratory and field evaluations of some botanical pesticides against the cedar leaf moth, Acleris undulana

The cedar leaf moth (CLM), Acleris undulana Walsingham, has recently become an important pest in the cedar forests in southwestern Turkey. Control has focussed on the use of synthetic chemical pesticides, with little research having been conducted on alternative control methods. In this study, four botanical pesticides (two commercial neem products, Neemazal-T/S® and Greeneem® oil, and two hot water plant extracts, Origanum onites L. and Pimpinella anisum L.) were evaluated for their effects against young (first–second) and older (third–fifth) instar larvae of CLM under laboratory and field conditions. The results of larval dip bioassay in the laboratory showed that all the botanical pesticides tested had significant larvicidal activity against both young and older instars of CLM compared to the water-treated control. Of the botanical pesticides tested, Neemazal was the most larvicidal botanical, causing mortalities ranging from 84 to 100%, the least effective was the P. anisum extract, but at high concentrations this extract still caused significant mortality. Results from field trials also revealed that the botanical pesticides had larvicidal activity against CLM. Neemazal was the most larvicidal botanical, followed by Greeneem oil then by O. onites and finally by P. anisum. Our overall results suggest that all the botanical pesticides tested are promising as larvicides against CLM, and may provide an alternative control method that is more compatible with Integrated Pest Management programs than the use of synthetic chemical pesticides.

04/003235 Economic optimization of low-flow solar domestic hot water plants: Cardinale N. et al. Renewable Energy, 2003, 28 (12), 1899–1914

04/003235 Economic optimization of low-flow solar domestic hot water plants: Cardinale N. et al. Renewable Energy, 2003, 28 (12), 1899–1914

Economic optimization of low-flow solar domestic hot water plants

A solar plant for hot-water production was investigated by the dynamic simulation code (TRNSYS). A typical daily home consumption for a 4 persons family was considered. The hot-water demand temperature (53 °C) is controlled by a conventional fuel auxiliary heater and a tempering valve. A heat-exchanger is considered between collector and storage tank. The fluids circulate by pumps activated by photovoltaic panels. This simplifies plant control systems and allows for stand-alone utilization of the plant. Annual energy performance, in terms of solar fraction, was calculated for three Italian localities. The economic viability of such a plant was evaluated with the life cycle savings (LCS) method, considering three conventional fuels (Gas-Oil, LPG and Electricity). Italian Government incentives show an economic viability only in comparison with electrical energy.

Motala energi investment in biomass and fluidized-bed technology

Motala Energi AB, Sweden, is increasing the output of its district-heating network and simulatneously switching from oil and electricity to biomass. The new hot-water plant is a bubbling fluidized-bed boiler built by Kvaerner EnviroPower in Gothenburg, which gives a thermal output of 27MW with flue-gas heat recovery

The Earl's Court Exhibition Centre

THE new Earl's Court Exhibition building, erected on the site of its predecessor, is approaching completion. It will be the largest permanent exhibition and sports centre in the British Isles. The site covers approximately twenty acres, the new buildings enclosing nine acres. The main arena is unique, as it is the largest concrete building in the country. There are no less than six electric railway tracks running underneath the site of this exhibition. These tracks were covered in by tunnels or bridged without interrupting the railway services. The main hall itself is 250 feet by 350 feet without columns, and has seating accommodation for about 25,000 people. A swimming pool having a capacity of 2¼ million gallons of water is provided. An account is given in the Electrical Times of July 1 of the problems connected with the heating and lighting of the exhibition. Complete designs and estimates were got out for all reasonable methods of doing this. The first step taken was to prepare designs and costs for a complete generating power station for the Exhibition and alternatively to use boiler-house plant for heating purposes. This was compared with possible tariffs obtained from the Fulham Power Station for an electric service for lighting power and complete heating of the building by electric thermal storage. The estimates were considered by the Company and its consultants, the conclusion being that electricity for all purposes was the best scheme. The Fulham Borough Council has undertaken to carry out the complete installation of all the electrical plant and services required up to the point of low-tension distribution together with the electric thermal storage plant, and the work is now on the point of completion. A permanent form of fire-fighting equipment is installed at every substation. The heating of the whole of the building is carried out by an electric thermal storage hot water plant which is much the largest plant of this kind in the British Isles.

Air-Conditioned Flats

EATON HOUSE, Upper Grosvenor Street, London, W.I, has been converted into a building containing thirty luxury flats. They are equipped for electric cooking and refrigeration, and hot water is supplied from a central hot water plant in the basement. We learn from the Electrician of November 6 that each tenant has an air-conditioning plant completely under his own control. Both the temperature and humidity of the air can be adjusted by the tenant to any value he pleases. In each flat there is a condensing unit working in conjunction with an air-conditioner, consisting of a slow-speed fan and motor, heating coils, cooling and dehumidifying coils, air filter and humidifying spray for winter use. The air-conditioners are housed in cupboards in the kitchens of each flat and cleverly concealed. Each conditioner passes approximately 1,300 cub. ft. of air per minute. About twelve complete changes of air per hour are provided in the rooms. It is essential that the plants be practically inaudible as they are in operation twenty-four hours a day. This has been effected by mounting the units in pedestal anti-vibrators. The filtered fresh air enters through grilles in the walls, and as there is no need to open windows street noises, grime and dust can be kept out. A small wall panel in the hall of each flat carries the temperature and humidity control apparatus. It consists of a thermostat, humidistat and change-over rotary switch. An advantage of individual control is that if a flat be left empty, the entire plant can be switched off and thus save running costs. The equipment was designed and installed by York, Shipley, Ltd. of North Circular Road, London, N.W.2. For the electricity the tenants pay a small quarterly fixed charge and Jd. per unit.