Use Of Cooling Water Research Articles

Effects of a Sprinkler and Cool Cell Combined System on Cooling Water Usage, Litter Moisture, and Indoor Environment of Broiler Houses.

Climate change is a serious challenge to food production around the world. Sustainability and water efficiency are critical to a poultry industry faced with global production concerns including increased demands for high-quality, affordable animal protein and greater environmental pressures resulting from rising global temperatures, flock heat stress, and limits on water availability. To address these concerns, a commercial sprinkler system used in combination with a cool cell system was evaluated against a cool cell system alone for two summer flocks of heavy broilers at Mississippi State University to determine effects of sprinkler technology on cooling water usage, litter moisture, and in-house environments. Environmental data were calculated and recorded throughout the flocks. The combination house exhibited a 2.2 °C (4 °F) increase in daily maximum temperature, lower coincident relative humidity, and a 64% (62,039 L/flock) reduction in average cooling water usage over the cool cell-only house. Litter moisture for the combination house tended to be numerically lower but showed no significant difference at several time points between and across flocks. A combined sprinkler/cool cell system reduced cooling water use by 64% over two flocks compared to a cool cell alone system and decreased in-house relative humidity levels.

Optimum dynamic operation of integrated absorption-compression refrigeration cycles and thermal energy storage systems for district cooling

A holistic approach is presented for the systematic assessment of the steady-state and dynamic performance of integrated absorption-compression refrigeration configurations that exploit thermal energy storage (TES). Thirteen configurations are evaluated including a dual vapor compression cycle (VCR), stand-alone single and double absorption refrigeration cycles (ABR) with two different working fluids (conventional NH3/H2O and novel acetaldehyde/DMF mixture), and their combinations thereof (VCR-ABR in parallel or cascaded configurations). The evaluation criteria combine steady-state performance metrics such as capital and energy cost, coefficient of performance (COP) and cooling water utilization, with dynamic operation indicators such as demand satisfaction, cooling and total energy utilities during transients between different operating levels. The dynamic operation optimization variables are the energy input per hour and the share of cooling output heading to each end-user. For all combined configurations, the resulting VCR cost is significantly lower compared to the nominal case of a dual VCR. The cascaded VCR-ABR configurations exhibit 241% higher VCR COP values than the nominal case. The latter also presents an average of 8.79% higher cooling water utilization than all the alternatives. The employment of TES enables the satisfaction of higher cooling demand than the cycle’s nominal cooling capacity. ABR-equipped configurations satisfy the cooling demand 16.47% more effectively than the dual VCR. The latter is attributed to the ABR ability to operate in part load when at nominal efficiency, while presenting better dynamic cooling water use. The electricity requirements are reduced by 49% and 69% in the parallel and cascaded VCR-ABR configurations, compared to the nominal case.

The water consequences of a transitioning US power sector

The US power sector is in a state of transition, prompted by significant shifts in technological innovations, energy markets, regulatory structures, and social pressures. As the electricity generation fleet changes, so too does the spatial & temporal distribution of the cooling water requirements for power plants. However, to date, these impacts have yet to be quantified. This study uses power plant-specific fuel consumption, generation, and cooling water use data to assess changes in the water withdrawn and consumed by thermoelectric power plants across 8-digit Hydrologic Unit Code (HUC-8) watersheds between 2008 and 2014. During this period, a few prominent trends are noted, including transitions in generation from coal-fired steam to natural-gas combined cycle units, from once-through cooling to wet recirculating towers and dry cooling systems, and from traditional fresh and saline surface cooling water to reclaimed water and groundwater sources. Total US cooling water withdrawals and consumption volume decreased from 2008 to 2014. The average water withdrawn per unit of electrical output decreased over this time, while changes in water consumption rates stayed relatively flat. Changes in water use at the watershed scale were unevenly distributed, as some water-scarce regions experienced increases in cooling water usage for thermal power plants, while others experienced significant water reductions and environmental benefits, especially where coal-fired generation was retired or retrofitted. The results from this study underscore the importance of evaluating water withdrawals and consumption at local spatial scales, as the water extraction, water quality and environmental health consequences of power plants on downstream users are non-uniform.

Water use in China’s thermoelectric power sector

Abstract We quantify the current water use of China’s thermoelectric power sector with plant-level data. We also quantify the future implications for cooling water use of different energy supply scenarios at both a regional and national levels. Within China, water withdrawal and consumption are projected to exceed 280 and 15 billion m 3 respectively by 2050 if China does not implement any new policies, up from current levels of 65.2 and 4.64 billion m 3 . Improving energy efficiency or transforming the energy infrastructure to renewable, or low-carbon, sources provides the opportunity to reduce water use by over 50%. At a regional level, central and eastern China account for the majority of the power sector’s water withdrawals, but water consumption is projected to increase in many regions under most scenarios. In high-renewable and low-carbon scenarios, concentrated solar power and inland nuclear power, respectively, constitute the primary fresh water users. Changing cooling technology, from open-loop to closed-loop in the south and from closed-loop to air cooling in the north, curtails the power sector’s water withdrawal considerably while increasing water consumption, particularly in eastern and central China. The power sector’s water use is predicted to exceed the regional industrial water quota under the ‘3 Red Line’ policy in the east under all scenarios, unless cooling technology change is facilitated. The industrial water quota is also likely to be violated in the central and the northern regions under a baseline scenario. Moreover, in line with electricity production, the power sector’s water use peaks in the winter when water availability is lowest. Water-for-energy is a highly contextual issue – a better understanding of its spatio-temporal characteristics is therefore critical for development of policies for sustainable cooling water use in the power sector.

Water and climate risks to power generation with carbon capture and storage

Carbon capture and storage (CCS) provides the opportunity to minimize atmospheric carbon emissions from fossil fuel power plants. However, CCS increases cooling water use and few studies have simulated the potential impacts of low flows on CCS power plant reliability. We present a framework to simulate the impacts of natural hydrological variability and climatic changes on water availability for portfolios of CCS capacity and cooling technologies. The methods are applied to the River Trent, the UK’s largest inland cooling water source for electricity generation capacity. Under a medium emissions climate change scenario, the projected median reductions in river flow by the 2040s was 43% for Q99.9 very low flows and 31% in licensable abstractions between Q99.9 and Q91. With CCS developments, cooling water abstractions are projected to increase, likely exceeding available water for all users by the 2030s–2040s. Deficits are reduced when wet/dry hybrid tower cooling is used, which may increase reliability at low flows. We also explore alternative water licensing regimes, currently considered by the UK Government. Climate change and growing cooling demands, individually and jointly present risks that will be prominent by the 2030s, if unaddressed. These risks may be managed if water-efficient abstraction is prioritized when supplies are limited.

European scale climate information services for water use sectors

This study demonstrates a climate information service for pan-European water use sectors that are vulnerable to climate change induced hydrological changes, including risk and safety (disaster preparedness), agriculture, energy (hydropower and cooling water use for thermoelectric power) and environment (water quality). To study the climate change impacts we used two different hydrological models forced with an ensemble of bias-corrected general circulation model (GCM) output for both the lowest (2.6) and highest (8.5) representative concentration pathways (RCP). Selected indicators of water related vulnerability for each sector were then calculated from the hydrological model results. Our results show a distinct north–south divide in terms of climate change impacts; in the south the water availability will reduce while in the north water availability will increase. Across different climate models precipitation and streamflow increase in northern Europe and decrease in southern Europe, but the latitude at which this change occurs varies depending on the GCM. Hydrological extremes are increasing over large parts of Europe. The agricultural sector will be affected by reduced water availability (in the south) and increased drought. Both streamflow and soil moistures droughts are projected to increase in most parts of Europe except in northern Scandinavia and the Alps. The energy sector will be affected by lower hydropower potential in most European countries and reduced cooling water availability due to higher water temperatures and reduced summer river flows. Our results show that in particular in the Mediterranean the pressures are high because of increasing drought which will have large impacts on both the agriculture and energy sectors. In France and Italy this is combined with increased flood hazards. Our results show important impacts of climate change on European water use sectors indicating a clear need for adaptation.

Quantifying the Impact of Renewable Energy Futures on Cooling Water Use

AbstractThis article presents an empirically based model, WiCTS (Withdrawal and Consumption for Thermoelectric Systems), to estimate regional water withdrawals and consumption implied by any electricity generation portfolio. WiTCS uses water use rates, developed at the substate level, to predict water use by scaling the rates with predicted energy generation. The capability of WiCTS is demonstrated by assessing the impact of renewable electricity generation scenarios on water use in the United States (U.S.) through 2050. The energy generation scenarios are taken from the Renewable Energy Futures Study performed by the U.S. National Renewable Energy Laboratory of the U.S. Department of Energy. Results indicate reductions in water use are achieved under these renewable energy scenarios. The analysis further explores the impact of two modifications to the modeling framework. The first modification presumes geothermal and concentrated solar power generation technologies employ water‐intensive cooling systems vs. cooling technology that requires no water. The second modification presumes all water‐intensive cooling technologies use closed cycle cooling (as opposed to once‐through cooling) technologies by 2050. Results based on one of the renewable generation scenarios indicate water use increases by over 20% under the first modification, and water consumption increases by approximately 40% while water withdrawals decrease by over 85% under the second modification.

Electricity generation and cooling water use: UK pathways to 2050

Thermoelectric generation contributes to 80% of global electricity production. Cooling of thermoelectric plants is often achieved by water abstractions from the natural environment. In England and Wales, the electricity sector is responsible for approximately half of all water abstractions and 40% of non-tidal surface water abstractions. We present a model that quantifies current water use of the UK electricity sector and use it to test six decarbonisation pathways to 2050. The pathways consist of a variety of generation technologies, with associated cooling methods, water use factors and cooling water sources. We find that up to 2030, water use across the six pathways is fairly consistent and all achieve significant reductions in both carbon and water intensity, based upon a transition to closed loop and hybrid cooling systems. From 2030 to 2050 our results diverge. Pathways with high levels of carbon capture and storage result in freshwater consumption that exceeds current levels (37–107%), and a consumptive intensity that is 30–69% higher. Risks to the aquatic environment will be intensified if generation with carbon capture and storage is clustered. Pathways of high nuclear capacity result in tidal and coastal abstraction that exceed current levels by 148–399%. Whilst reducing freshwater abstractions, the marine environment will be impacted if a shortage of coastal sites leads to clustering of nuclear reactors and concentration of heated water discharges. The pathway with the highest level of renewables has both lowest abstraction and consumption of water. Freshwater consumption can also be minimised through use of hybrid cooling, which despite marginally higher costs and emissions, would reduce dependence on scarce water resources thus increase security of supply.

Biomass and number of fish impinged at a nuclear power plant by the Baltic Sea

The main aim of this study was to investigate the number and biomass of impinged fish at Forsmark Nuclear Power Plant in Sweden, located on the coast of the Baltic Sea. Of particular interest was the number of impinged individuals of the critically endangered European eel (Anguilla anguilla) which is regularly caught in the cooling system. Another aim was to determine the comparability of the results from Forsmark and results from impingement studies in other types of waters. Cross-systems studies make it possible to (1) estimate fish loss at plants where fish is not counted, and (2) to predict changes in fish loss from changes in electricity production or cooling water use. In 2010, 31,300,000 fish with a total biomass of 62,600 kg were impinged at Forsmark. In 2011, 27,300,000 fish weighing 38,500 kg were impinged. The maximum peak in total fish number and biomass occurred in spring. The most critical period for herring was in late summer and early autumn. Regarding eel, the largest impingement losses were recorded in November. The number of fish agreed with earlier established quantities of impinged fish in both freshwater and marine ecosystems. The study also estimated that 1,300 critically endangered eels could survive at Forsmark each year if a fish return system would be constructed to allow the passage of fish from the plant back to the Baltic Sea.

Agricultural aspects in river basin management plans

In the European Region agriculture is the second largest water user after power industry cooling water use. As part of the implementation of Water Framework Directive EU Member States prepared their river basin management plans by the end of 2009 or first half of 2010, In these plans impacts of agriculture on water bodies have received attention. The detailed information elaborated in the plans by countries and river basin districts were uploaded into the WFD section of the WISE system. This database provides opportunity for multi-criteria analysis for different water types. The paper discusses the effects of agriculture on hydromorphological pressures and impacts affecting surface water bodies. It was pointed out that among the pressures affecting European surface water bodies the hydromorphological and diffuse pressures represent the highest ratios (Figure 1). Within the hydromorphological pressures affecting classified surface water bodies the ratio of pressures related to agricultural activities is low,it does not exceed 1% at European level. In case of Hungary the agriculture related river management pressures effect about 80% of the surface water bodies, which is much higher than the corresponding European average. The agricultural water abstractions affect about 10% of the Hungarian surface water bodies (Figures 2 and 3). The river and lake water bodies are impacted in significant ratio by nutrient enrichments and organic material enrichments, while in case of river water bodies the impact of organic material enrichments is also significant (Figures 4 and 5).

Carbon capture effects on water use at pulverized coal power plants

Abstract Significant quantities of water are utilized in thermoelectric power plants, mostly for the purpose of cooling. Water is becoming critically important for low carbon power generation. To reduce greenhouse gas emissions from pulverized coal (PC) power plants, post-combustion carbon capture systems are receiving considerable attention. However, current systems require a significant amount of cooling, which puts further pressure on cooling water resource. This paper quantifies cooling water use and evaluates technical and economic effects of carbon capture on cooling systems at PC power plants. Included are recirculating systems with wet cooling towers and air-cooled condensers (ACCs) for dry cooling. For a wet cooling tower, water has to be provided to make up losses due mainly to evaporation and blowdown. Adding an amine-based carbon capture system to the plant would approximately double water use. When air-cooled condensers (ACCs) are used as the dry cooling system, in spite of the advantage in reducing water usage, the dry cooling system has a much larger capital cost than the wet cooling system, depending strongly on specific site and system characteristics.

Analysis of alternative secondary heat uses to improve energy efficiency—case: A Finnish mechanical pulp and paper mill

This study considers different alternative uses of secondary heat in a mechanical pulp and paper mill. The considered alternatives are (1) three different heat exchanger network retrofits, (2) drying of bark, (3) drying of primary and activated sludge and (4) drying of both bark and sludge. The data has been gathered from an operating mill and a simulation model has been built to examine the mill-wide effects of the proposed changes. Targets for steam and cooling water use, used in the heat exchanger network retrofits, have been evaluated using pinch analysis. The amount of available secondary heat found in the pinch analysis can be used in drying of bark or sludge. Sludge is typically burned together with mill fuel in the bark boiler of a power plant to deliver heat and electricity to the mill. These wood-based biofuels typically consist of 50% w.b. water, which will evaporate and consume some of the fuel's energy content during combustion. Fuel drying is a way to increase the heating value of fuels and to increase the energy efficiency of heat and power production. The utilisation of low-temperature secondary heat in the drying may reduce the need for fuels and primary energy in the mill. The different ways of using the secondary heat have different effects on primary fuel consumption and electricity production. Therefore the different results are compared using the reduction of CO 2 emissions as a common criterion. The results show that all the considered alternatives have great energy-saving potential up to 8 MW steam use in winter and 6 MW in summer time.

Membrane separation in solvent lube dewaxing

AbstractExxon Mobil Corporation and W.R. Grace have developed an enhanced process for recovering solvents used in the refining of lubricants. The membrane‐based process provides higher yields of lube oil, while simultaneously consuming less energy, decreasing cooling water use, and potentially reducing the level of volatile organic emissions from the dewaxing operation. The yield increase equates to a process savings, for a typical commercial plant, of about 2 million barrels of crude oil per year. By recovering and recycling the dewaxing solvent while bypassing the energy intensive parts of the plant, a single facility could reduce fuel oil consumption by 36,000 barrels/year, and greenhouse gas emissions by about 20,000 tons/year for each plant. The same plant would reduce cooling water use by nearly 4 million gallons/day, and, the release of dewaxing solvents, which are volatile organic materials, could be decreased by 50–200 tons/year per plant depending on the mechanical condition of its equipment. This technology was first implemented commercially at Exxon Mobil's Beaumont, Texas, Refinery. It can be easily retrofitted into existing plants or incorporated into new plant designs, and is currently available for license as the trademarked process MAX‐DEWAX®.

Cooling water use patterns at US nonutility electric generating facilities

Cooling water is used by many industrial facilities. The largest user of cooling water is the electric power industry, although other significant users include the pulp and paper, chemical, iron and steel, aluminum, and petroleum refining industries. The US Environmental Protection Agency (EPA) is currently developing regulations to implement section 316(b) of the Clean Water Act, which deals with cooling water intake structures. The EPA will examine cooling water use patterns at various industries. Data pertaining to cooling water use patterns at utility plants are readily available; however, no information has been assembled for cooling water use at electric power generating facilities owned or operated by entities other than utilities (nonutilities). This paper presents data concerning cooling water use from two subsets of the nonutility sector and focuses on plants using once-through cooling systems. The first subset includes 123 nonutility plants that each generate at least 150 MW of power. Collectively, they represent 41,494 MW of generating capacity, or about 56% of the total nonutility generating capacity. Approximately 17% of the installations within that subset utilize once-through cooling water. The second subset includes 58 waste-to-energy facilities, which individually produce less than 80 MW but collectively generate about 2200 MW. Only 11% of this subset of plants uses once-through cooling water. The total 15,372 MW generated by once-through nonutilities is equivalent to only 6% of the 258,906 MW generated by utilities utilizing once-through cooling. From a national perspective this share may appear relatively insignificant. However, in some states, the nonutility once-through total is equivalent to a more significant percentage of the utility once-through total.

Entrainment and Impingement of Fish by Power Plants in the Great Lakes which use the Once-Through Cooling Process

There are 89 thermal electric generating stations, producing 54,118 Megawatts (Mwe) of electricity, which use water directly from the Great Lakes. Electrical production per capita in Canada, 3.34 kw, is about twice that of the United States, 1.32 kw. These power plants require almost 2000 m 3 s −1of cooling water or, conservatively, >30% of the flow of the St. Lawrence River. Cooling water use is directly related to Mwe production and 176 L are required per kilowatt. The majority (76%) of power plants cause temperature increases of 12° C or less. Impingement of fish is directly related to power plant size (log 10 number impinged = 0.414 + 1.844 log 10 Mwe capacity) and we calculated that more than 100 × 10 6 fish will be lost at existing and proposed stations. Impingement results in direct losses to the fishery of more than 25%, by weight, of the annual commercial fish harvest. Entrainment is also directly related to power plant size (log 10 number entrained = 2.103 + 1.658 log 10 Mwe capacity) and we expect more than 1.28 × 10 9 larval fish will be lost by entrainment. These estimates of entrainment and impingement are conservative since they are based upon rated pumping capacity, not actual usage which was 67% for the few plants that provided this information. Impingement losses, when combined with entrainment losses which will affect recruitment to some unknown degree, likely constitute a significant undersirable impact upon the Great Lakes fishery.

Factors in Supply and Use of Cooling Water

Abstract WE OF the rubber industry are naturally interested in water mainly as a cooling agent. We are concerned with its source, the quantities regularly available and the temperature at which it is supplied. A reference to the requirements of the Goodyear factories in Akron indicates how important a factor it is. The two plants must be supplied with over 20,000,000 gallons of water per day exclusive of the amount taken from the city mains for special purposes. Approximately 13,250,000 gallons of this volume are used for cooling mills, internal mixers, calendars and tubing machines. The greater proportion of this is recovered and with the addition of fresh water is employed for cooling heaters, in the reclaiming plant and for various services throughout the factories. When the day's cycle has been completed, more than 13,000,000 gallons of warm water are returned to their principal source, the Little Cuyahoga River. In the cooler seasons all of the 13,250,000 gallons of cooling water come from the impounded waters of the river, which is fed largely by Wingfoot Lake and partly by Springfield Lake. During the summer the daily supply is a mixture of deep well water and the necessary balance from the river.