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  • Radioactive Waste: Can Membranes Reduce The Fear Factor?
    Nuclear Chemistry and Technology INCT showed that reverse osmosis RO can be useful for the treatment of liquid low level radioactive institutional wastes The application of membranes at the beginning of the cleaning cycle reduced significantly the energy consumption of the whole system Example The RO method developed by INCT has been implemented at the Radioactive Waste Management Plant RWMP in Swierk Poland It is a three stage RO system The first two stages are used for decontamination to produce the effluent that after radiometric control can be safely released into the sewage system The third stage is applied for the volume reduction by concentrating retentate obtained from the first two stages Spiral wound RO modules were used in the installation Nanofiltration The nanofiltration NF process allows for the separating of monovalent ions from multivalent ions which are retained by the membrane with pores in the 0 001 to 0 01 μm micrometers size range microns μ are a familiar equivalent to micrometers The process can be used for separation of organic compounds of moderate molecular weight from monovalent ions present in the solution The well known application of NF in the nuclear industry is boric acid recovery from contaminated cooling water in nuclear reactor Example Australian Nuclear Sciences and Technology Organisation ANSTO tested different commercial nanofiltration membranes in a cross flow membrane cell for the treatment of uranium mill effluents The rejection of uranium was greater than 75 percent Some of the tested membranes showed potential for separation of radium sulphate and manganese Ultrafiltration Ultrafiltration UF uses membranes of pore sizes between 0 001 and 0 1 μm In such a case dissolved compounds pass through the membrane while colloid and suspended matters are rejected In the nuclear industry UF can be used for removal of all substances that are present in radioactive waste in colloidal or suspended form UF can be also applied as a pretreatment stage before reverse osmosis Very often UF is combined with sorption precipitation or complexation in one hybrid process of enhanced ultrafiltration Small ions bound by macromolecular agents form complexes which can be retained by UF membranes Radioactive cations can be also separated in the precipitation process forming less soluble particles carbonates phosphates and oxalates or hydroxides which can be later retained by the UF membrane The hybrid complexation UF or precipitation UF methods are effectively applied in several plants processing alpha α bearing radioactive waste streams Example Waste originating from floor drains and equipment drain tanks as well as from the reactor coolant system was processed with UF at the Callaway Nuclear Generating Station in the U S near Fulton MO Four UF modules were used to treat reactor coolant water 70 percent of radioactivity and suspended solids were removed with UF and permeate was additionally polished with ion exchange to the minimum detectable level Microfiltration Microfiltration MF membranes reject bigger particles and macromolecules with size of 0 1 to 1 μm In nuclear technology the process is used either for pretreatment

    Original URL path: http://www.wateronline.com/doc/radioactive-waste-can-membranes-reduce-the-fear-factor-0001 (2016-02-14)
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  • The Vulnerability Of The Energy Sector To Water Scarcity
    higher efficiency power plants with more advanced cooling systems that reduce withdrawals but increase consumption per unit of electricity produced and by expanding biofuels production the IEA states in its report Water energy stress is an issue worldwide But areas with high energy demands are feeling the most impact The IEA reports on the vulnerability of the energy sector to water constraints in several of those countries China As China continues to grow and urbanize so does the country s demand on water Water withdrawals for energy production in China are predicted to rise by 38 percent by 2035 says the IEA Much of that water is dedicated to the growing nuclear solar and shale gas industries While all existing nuclear plants in China use seawater for cooling future plans include the development of inland nuclear power facilities which will require more freshwater withdraw Additional solar power plants are also planned many in the sun belt the country s driest region Particular sites will have to take into account the availability of water resources and the case for installing more expensive dry or hybrid dry wet cooling systems the IEA states Shale gas production is also focused in dry regions The Tarim Basin in the Xinjiang Uyghur Autonomous Region for example holds some of the country s largest shale gas deposits but suffers from severe water scarcity Aware of the growing water issues in the energy and other sectors the Chinese government is pushing ahead with water reforms and increasingly stringent regulations and enforcement procedures aimed at improving water conservation India The Indian energy sector which is primarily focused on power generation doesn t currently account for a large share of the country s water However the IEA predicts that water withdrawals for energy production in India will grow by almost 50 percent by 2035 Water consumption is expected to grow at an even faster rate At the same time the availability of water is becoming a larger issue in India The country s main sources of water glacier melt and rainfall are unevenly distributed with most rainfall coming from June to September Severe droughts have occurred as recently as 2009 and 2012 In 2010 a water shortage caused coal fired power station in Maharashtra to shut down leading to power outages A similar event happened in 2012 United States The U S energy sector is most vulnerable in the western part of the country where drought conditions are getting worse Water use already exceeds sustainable levels in the region which faces growing water and electricity demand as the population increases Low water availability has occasioned the reduction of output from coal fired power plants and hydropower facilities in some cases and put it seriously at risk in others threatening blackouts and higher cost electricity reports the IEA This is not the first time in U S history that drought has impacted the energy industry In 2007 and 2010 water scarcity forced operations to be scaled back at hydropower facilities

    Original URL path: http://www.wateronline.com/doc/the-vulnerability-of-the-energy-sector-to-water-scarcity-0001 (2016-02-14)
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  • Predicting The Impact Of EPA’s Proposed Power Plant Effluent Limits
    WWEMA board of directors The EPA is absolutely right that power plants are responsible for a high level of metals and other contaminants being released into the environment said Dimitriou who is also the president of WRT a manufacturer of treatment systems for water contaminant removal But they aren t addressing the problem effectively which is going to make it difficult for power plants to comply A big concern for members of the power industry is paying for the new technology that would be required to comply with the EPA s proposed regulations Under these rules regulations power plants would need to either install new treatment technologies to reduce the amount of pollutants discharged or implement process changes that completely eliminate discharge like dry handing or closed loop systems There are approximately 1 200 steam electric power plants in the U S and around 500 are coal fired units which will be most heavily affected by these regulations Many of them cannot currently afford the upgrades required to comply according to Dimitriou The cost is going to be significant for them Dimitriou stated A month after the publication of this proposed rule several power plants closed because they knew they would not be able to afford these changes The general consensus in the industry seems to be that this rule is going to force changes that in the long term are going to be very expensive Dimitriou believes this expense will have a sizeable impact on the power industry disproportionally impacting the Northeast where most coal fired power plants are located It is forcing power plants to either switch to natural gas or close he says It will impact the cost of electricity and the availability of it It will likely raise rates significantly for the consumer EPA statements tell a different story Under the most stringent preferred regulatory option and assuming 100 percent pass through of costs to consumers EPA projects the average monthly electricity bill for residential consumer will increase by 22 cents or 0 23 percent the agency stated in a webcast presentation on the proposal titled Steam Electric Power Generating Effluent Guidelines In the same presentation the EPA estimated that annual costs will be between 185 million and 954 million per year for the power industry to comply with the proposed regulations They don t project any plants closing as a result of the regulations Many power utilities think the EPA cost estimates are off by a factor of 10 said Dimitriou They need to reevaluate how much this is truly going to cost the power industry he said Implementing the technology required to comply with these regulations could also be a challenge for the industry The previous regulations established in 1982 were based on the use of settling ponds and were mainly focused on suspended solids Updating to comply with the new regulations would mean installing unfamiliar technology for some power plants There has been no emphasis to do anything like this before said Dimitriou

    Original URL path: http://www.wateronline.com/doc/predicting-the-impact-of-epa-s-proposed-power-plant-effluent-limits-0001 (2016-02-14)
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  • Can Co-Locating Utilities Solve The Water-Energy Nexus
    the nexus It s only one side of the coin however Water and wastewater operators experience the other side chewing through electricity and their budgets to treat and transport water Resources being a scarce commodity it s incumbent upon us to optimize the use of water and energy as best we can While conservation is the prime course of action for the public the best solution for utilities may be to work smarter by having the water energy nexus work for us instead of against us One trending way to do this is by co locating water wastewater treatment and power generation at a single facility Described below are two examples of colocation and innovation Combined Heat And Power CHP DC Water in Washington D C is among the most forward looking innovative utilities in the U S proving it once again by constructing the world s largest combined heat and power CHP plant at its Blue Plains facility CHP also called cogeneration uses a heat engine a system that converts heat or thermal energy to mechanical energy to simultaneously generate electricity and useful heat Blue Plains will take heat from the 370 MGD of effluent it receives and turn it into 10 megawatts of off grid electricity The 450 million project relies on thermal hydrolysis a process that pressure cooks the waste before microbes convert it into methane in digesters The methane powers turbines to generate electricity while heat captured off the turbines is recycled into the thermal hydrolysis process According to DC Water General Manager George Hawkins the project will save the utility 10 million per year once completed due this summer Combined Power And Desalination Combined power and desalination plants or hybrid desalination plants produce drinking water and electricity by aligning the processes side by side waste heat from the power plant is used as the heat source for desalination Ideal for arid regions prone to drought pay attention California it makes sense that the first such facility was built at Qidfa Fujairah in the United Arab Emirates completed in 2004 for 1 2 billion The Fujairah plant recently approved an upgrade that will further take advantage of the water energy nexus by capturing residual energy from the reverse osmosis process which pumps seawater through membranes at pressures as high as 70 bar Special rotary devices will harness and return the energy to the pumps for more sustainable cost effective operation Other hybrid desalination plants have been constructed throughout the Middle East but Fujairah remains the leader As the cost for the notoriously high energy spend of desalination is improved and as desalination becomes more of a necessity this type of co location is sure to become more common Nexus Gains Steam In The U S Here in the U S we are voracious but improving consumers of both water and electricity having been blessed for so long with a cheap abundant supply of each We have begun to feel the pinch however as population and demand

    Original URL path: http://www.wateronline.com/doc/can-co-locating-utilities-solve-the-water-energy-nexus-0001 (2016-02-14)
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  • Waste Heat Recovery For Desalination From Steam Power Plants
    and bunker C fuel oil jet fuel kerosene petroleum coke and waste oil Source U S Energy Information Administration Form EIA 023 Power Plant Operations Report For the purpose of this discussion we have taken the average of the six even numbered years 2002 2012 for petroleum SPPs as 10 835 Btu kWh 11 431 kJ kWh As it takes 3 412 Btus of energy to produce one kWh this means that only 31 5 percent of the energy in the fuel is converted to usable electrical energy whilst the remaining 68 5 percent are losses due to radiation friction generator ventilation and last but not least heat in the exhaust steam going to the condenser which is estimated at 60 percent of the total heat input In equivalent terms this represents 1 9 kWh of heat per kWh of electrical energy which needs to be disposed of in the condenser 2 85 litres of water would need to be evaporated per hour in the cooling tower plus at least 15 percent bleed to remove this amount of heat in the steam condenser This equates to 3 3 litres h per kWh As mentioned at the end of the previous section it is not necessary to use cooling water to condense the exhaust steam from the final stage turbine As long as a cold surface is provided for condensation the process is possible Refrigerated Steam Condensing It is possible using a refrigeration process to provide a cold condensing surface This has the advantage of no longer needing a cooling water system comprising pumps cooling towers and water treatment systems This would save cooling water at the rate of about 3 3 litres per hour per kW electrical energy generated including 15 percent bleed Referring to Figure 4 it is clear that a refrigerated condenser is able to maintain a steady condensing temperature which is independent of climatic influences on the cooling water temperature and thus the condensing temperature which can vary widely in hot humid climates If we set the heat pump discharge to a condensing temperature of say 70 C we can generate 70 C hot water which is hot enough as a heat source temperature for an MED plant To maintain a condensing temperature of 43 C the condenser surface temperature would need to be maintained at a temperature of about 38 o C Referring to Figure 5 the COP of a refrigeration compressor is 7 at 38 C refrigerant evaporating temperature and 70 C refrigerant condensing This means that the electrical energy required to handle a condensing heat load of 1 9 kW heat per kWh generated amounts to 1 9 7 0 27 kWh delivering a total heat of 2 17 kWh per kWh generated Source Boyce Mehervan P Handbook for Cogeneration and Combined Cycle Power Plants 2 nd Edition ISBN 978 0 7918 5953 7 Figure 4 Percent change in load and heat rate due to change in steam condensing pressure Source Johnson Controls Sabroe

    Original URL path: http://www.wateronline.com/doc/waste-heat-recovery-for-desalination-from-steam-power-plants-0001 (2016-02-14)
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  • Stormwater A Valuable Resource For Power Plants
    Bob Goldstein and his team at the Electric Power Research Institute EPRI are investigating the possibility of using stormwater runoff to the meet the large water demands of power plants The pressure is on the electric power sector to reduce its use of freshwater said Goldstein a senior technical executive of water and ecosystems at EPRI The power industry needs to create strategies and technologies that are effective in reducing water and still cost efficient Production of electrical power is one of largest uses of water in the United States Thermoelectric power withdrawals accounted for 49 percent of total water use according to the U S Department of the Interior Most of the water is used for cooling purposes Fortunately power plants do reuse most of the water they remove from the environment Because of this the total water consumption for power plants is only approximately 4 percent of total water withdraw in the U S But that smaller consumption requirement doesn t mean power plants are immune to water scarcity Although they are not consuming as much water they need a lot of water up front in order to function explained Goldstein So if they are in an area where the water supply is restricted because of drought or other reasons they need to have a strategy to conserve freshwater EPRI conducted two studies on the potential for stormwater use at power plants The first Evaluation of Stormwater as a Resource for Power Plant Cooling investigated the potential to use stormwater runoff in lieu of withdrawals from a freshwater body to meet water needs of different power plant processes The second study The Potential for Using Stormwater in Power Plants Lessons Learned from Case Studies at Two Great River Energy Plants took a more focused approach analyzing stormwater use at two power plants Elk River Energy Recovery Station in Minnesota and Coal Creek Generating Station in North Dakota It also considered generating stations with water demands similar to those of Coal Creek but placed in other climatic conditions representing Upstate New York Illinois and Southern California Two sources of stormwater were discussed and evaluated in both studies onsite and offsite Onsite stormwater runoff after being collected from the power plant s property and placed in sediment basins typically can be used without treatment in flue gas desulfurization systems which remove sulfur from exhaust gases before releasing them in ash systems and cooling towers in coal fired plants and in cooling towers in combined cycle oil gas and nuclear plants Offsite stormwater which usually is easier to procure in larger quantities can provide a significant volume of water for power plants There is potential for offsite stormwater to supply over half of the water requirements for some plants However the water must be evaluated carefully because offsite stormwater is more likely to have come into contact with substances they make it unsuitable for use without some form of treatment Transportation must also be considered when using offsite stormwater If it

    Original URL path: http://www.wateronline.com/doc/stormwater-a-valuable-resource-for-power-plants-0001 (2016-02-14)
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  • Latest Insights On Water & Wastewater Treatment For The Power Generation Industry Documents on Water Online
    to a wild ride of drought followed by devastating floods followed by drought and then more floods Selenium Removal Technologies A Review 1 15 2016 Selenium a contaminant of concern in industries such as mining oil refining and power generation is removed from wastewater principally through either biological or chemical physical processes This article will describe those technologies several technology providers and other sources of information Compliance Tips For EPA s New Power Plant Regulations 11 10 2015 Now that the final rule has been published in the Federal Register the stage is set for official implementation of the U S EPA s Steam Electric Power Generating Effluent Guidelines on Jan 4 2016 The Long Journey Of An Energy Water Bill In Texas 7 6 2015 Being an environmental advocate in Texas may seem like an uphill battle and I make no bones about the fact it most certainly is Straight Talk On Radiation 6 22 2015 From time to time I write on topics that are related to water and wastewater as a backgrounder so that those involved in the field can gain a wider perspective and have available to them a cogent explanation minus jargon on various topics By Dr J H Wakefield A Promise To Our Children To Save Water In Texas 5 4 2015 It s no secret that Texas is currently in the midst of a multi year drought yet the vast majority of our electricity comes from sources that contribute to this prolonged drought namely coal nuclear and natural gas All of these energy sources require copious amounts of water to produce electricity In Times of Drought 9 Economic Facts About Water In The United States 4 2 2015 This Hamilton Project memo presents nine economic facts that provide relevant background context to the

    Original URL path: http://www.wateronline.com/hub/bucket/latest-insights-on-water-wastewater-treatment-for-the-power-generation-industry (2016-02-14)
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  • Baron & Budd And Gomez Trial Attorneys File Seattle PCB Lawsuit Against Monsanto; Seattle Joins Five Other American Cities Against Monsanto
    home 20160126006531 en Seattle is the 6 th American city to file against Monsanto joining San Jose Oakland Berkeley San Diego and Spokane Case No 2 16 cv 00107 is in the Western District of Washington PCBs are man made chemical compounds that were produced by Monsanto Company in the United States from the early 1930s until the late 1970s when Congress banned the production and use of PCBs based on their danger to human and environmental health During those five decades Monsanto s PCBs were incorporated into a variety of products and applications including electrical equipment paints caulks and other building materials According to the suit Monsanto knew then that PCBs were toxic and could not be contained as they readily escaped into the environment finding their way into bays oceans lakes rivers streams soil and air Although Monsanto recognized internally that PCBs were becoming a global contaminant it concealed this information and increased production of these profitable compounds As a result PCBs are now a common environmental contaminant found in all natural resources including water bodies and plants as well as in the tissues of all forms of marine life animals and humans Detection of PCBs is a serious matter The chemicals can destroy fish habitats and are associated with illnesses and cancer in humans The Washington State Department of Ecology has determined that taking steps to reduce PCBs immediately is an effective method for achieving desired water quality goals and such methods require identifying and reducing PCBs at their sources in the watershed Attorney Scott Summy a shareholder at Baron Budd P C one of two firms representing Spokane in the lawsuit believes that Monsanto should shoulder the burden for the vast contamination No company should be allowed to contaminate the environment and rely upon taxpayers to

    Original URL path: http://www.wateronline.com/doc/baron-amp-budd-and-gomez-joins-five-other-american-cities-against-monsanto-0001 (2016-02-14)
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