Removal of Radioactive Material For Residential Purposes

Removal of Radioactive Material For Residential Purposes:

Removal of Radioactive M aterial F or Residential Purposes Focus: Well Water Systems By: Henry Macguire Michael Johnson Ben Bolger Owen Lapierre

Background:

Background 8.9 magnitude earthquake Shutdown of 3 reactors Reactors overheat Radioactive material leaves the plant from sea water and vapors Surface water is contaminated Iodine-131 Contamination causes thyroid cancer and other thyroid diseases 1 2

Slide 3:

400,000 people Focus on well water systems Removal of iodine 131 Citizens without access to municipal water systems Reliance on groundwater Fukushima Power Plant Iwaki City 3 4 5 Purpose 27 mi.

Schematic:

Schematic

Iodine Concentrations Calculations :

Iodine Concentrations Calculations Formula for Radioactivity: = Half Life ( 8.0197 days) or (692902.08 seconds) , N A =6.022 141 79×10 23 (Avogadro’s constant) m= mass of isotope in grams , = atomic mass Using the above equation we can find concentrations of Iodine-131 in water by using know radioactivity levels (see below) in water samples and Japanese regulations for Iodine 131 in drinking water(see below): 400 = Radioactive level in water sample of groundwater under reactors 215 = Radioactive Level in water sample in Iwaki 100 = Regulation in Japan for Allowed radioactive levels in drinking water Using these values we can solve for the mass of Iodine-131 in the Iwaki City sample thus giving us a concentration.

Slide 6:

Sample: Iwaki City (Sample used in Carbon and Ion Exchange Calc’s ) 10 23 m(grams)= 6.74497x10 -14 Concentration: = Sample : Japan regulations (Goal is to reduce Iwaki City Iodine 131 concentrations to below regulation levels) 10 23 m(grams)= 2.174537x10 -14 Concentration: = 2.174537x10 -14

Volume Calculations:

Volume Calculations water.siemens.com Carbon Filter Needed – 20 minutes of Empty Bed Contact Time (EBCT ), with flow Q= EBCT= Volume / Q ; 20 mins = Volume = 40L x ( = .04 m 3 Dimensions: H=.8 m , W=.25m , D=.2m Ion Exchange Column Needed – 1 min retention time, this is achieved with the timed valve switch system. Chamber needs to be big enough to hold 1 L of water, plus extra for the volume of resin. Rounded up to 1.5 L. Volume= 1.5L x ( = .0015 m 3 Dimensions: H=W=D=.115 m Storage Tank Needed – Enough drinking water for a small family for a day, and then some. Value chosen to be around 200 L. System filters effluent (clean water) into tank at 1 L/2min . Volume= 200L x ( = .2 m 3 Dimensions: H=1.2 m, W=0.3 m, D=0.6 m Time to Fill: 200 x = 6.666 hrs

Slide 8:

Life of Carbon Filter Assumptions/ Knowns : Volume of Column = 40 L, packed with granular carbon Flow Rate = 2 GAC Iodine # 1100= Iwaki City Concentration = 6.74497*10−14 Calcs : 1100= ( 6.74497*10−14 ) / ( ); g C = 2.45*10 −12 g mg Iodine per day? 200 ( 6.74497*10−14 ) = 1.348*10 −12 How long until filter must be replaced? 1100= ( 1.348*10 −12 ) / (2.45*10 −12 g) = (5506.09/ day)/1100 = 5 days

Head Loss and Pressure Drop:

Head Loss and Pressure Drop where u = velocity of fluid, d H = hydraulic diameter of pipe, and v = kinematic viscosity Head Loss: For Laminar Flow, friction factor, Lengths of Pipes: L 1 = 0.3 m and L 2 = 0.2 m Inner Diameter of Pipes: D = 5 cm or 0.05 m Pressure Loss:

Ion Exchange:

Ion Exchange Ion exchange is a chemical reaction where an ion from a solution is exchanged for a similarly charged ion attached to a solid particle. Iodine  anion dissolved in water(the solution ) I on exchange resin  solid particle Hydroxide  ion replaced Small batch reactor with a calculated amount of ion exchange resin 7 13

Resin:

Resin Mixed-bed bead resin, EPICOR AC-32 N uclear grade ion exchange resin. U sed at nuclear power stations. Mixed-bed: C ombination of cation and anion resins. Capacity to remove many other types of radioactive compounds. Iodine 131 will be the primary focus. 6 8 9

Ion Exchange Calculations:

Ion Exchange Calculations Maximum Capacity of Resin at Equilibrium Groundwater: pH 7.9 = 197,400 (equilibrium adsorption ratio) Concentration inflow from carbon filter = 2.174537E-16 x = 2.174537E-19 12

Slide 13:

Equivalence of I-131 and Resin (RNR)OH + = (RNR) + So, 1:1 charge ratio Selectivity Series Tc > CNS > I > NO3 > Br > CN > HSO4 = HSO3 > NO2 > Cl > HCO3 > OH > F = 197,400 = Replaces g rams of iodine suspended in water t hat can be removed p er gram of resin Resin 10 11 14

Accounting for Efficiency: :

Accounting for Efficiency : x (0.8) = 3.43403E-14 3.43403E-14 x (0.95) = 3.26233E-14

Usable Life of Resin:

Usable Life of Resin Need to purify 200 (conc. of I-131 in water) x (household water demand per day) = I-131 to be removed per day 2.174537E-19 x (200 ) = 4.34907E-17 Resin needs to remove this amount of I-131 per day Resin required to remove this amount of I-131 ( I-131 to be removed per day) x (1/effective capacity of resin) = resin required per day 4.34907E-17 = 0.0013 This value must be doubled 0.0013 x (2) = 0.00266 Yearly capacity 0.00266 = .973 ~ 1

Summary:

Summary Groundwater concentration Acceptable levels: 2.174537x10 -14 Concentration in outflow of carbon filter: 2.174537E-16 Percent removed with carbon filter: 99.68% Approximately 1% of acceptable levels Ion exchange theoretically removes 100% of contaminants, making the concentration if Iodine 131 well below acceptable levels post treatment process.

Sources:

Sources Picture References 1 http://i.space.com/images/i/8602/i02/japan-earthquake-map-110311.jpg?1299997843 2 http://shop.perkinelmer.com/Content/Images/smallImages/I131Radionuclide.gif 3 google.maps.com, my maps, Michael Johnson 4 google.maps.com, my maps, Michael Johnson 5 http://si.wsj.net/public/resources/images/OB-NE124_JFOODM_G_20110322153702.jpg 6 http://coffeesnobs.com.au/attachments/Ion_exchange_resin_beads.jpg 7 http://www.total-water.com/images/anion_resin_bead_2.png 8 http://www.epicorinc.com/MSDS/Bead%20%28B%29/AC-32%20Mixed%20Bed%20Resin.pdf 9 http://upload.wikimedia.org/wikipedia/commons/1/13/Cation%2Banion_exchanger.JPG 10 http://image.wistatutor.com/content/feed/tvcs/hydroxide20molecule.JPG 11 http://us.123rf.com/168nwm/splinex/splinex1103/splinex110300019/9150943-radionuclides-of-iodine-131-and-cesium-137.jpg 12 Owen Lapierre , drawn autocadd schematic 13 source 7, altered, Michael Johnson 14 source 7, altered, Michael Johnson 15 Michael Johnson, drawn schematic 16 Wastewater Engineering: Treatment and Reuse Ion Exchange references: [1] ‘adsorption and desorption of selected 10 CFR part 61 radionuclides from ion exchange resin by waters of different chemical composition’ [2] http://www.evs.anl.gov/pub/doc/Iodine.pdf [3] Dorfner (1979) [4] http://www.rpi.edu/dept/chem-eng/Biotech-Environ/IONEX/resins.htm [5] http://www.epicorinc.com/MSDS/Bead%20%28B%29/AC-32%20Mixed%20Bed%20Resin.pdf [6] Britt Holmen’s book [7] http://www.epa.gov/rpdweb00/radionuclides/iodine.html#properties