Technology Selection Tools for Boiler Feedwater Applications (US Units)

Technical Paper Technology Selection Tools for Boiler Feedwater Applications (US Units) Authors: Robert Gerard and Roch Laflamme, GE Water & Process Technologies Introduction During the last decade, the General Electric Company has created a Water and Process platform within the Infrastructure division by bringing together leading companies in the water industry. These acquisitions include Glegg, Betz, Osmonics, Ionics and Zenon, among others. The integration of these businesses has created a powerful force with a range of cutting edge technologies to help customers improve performance and reduce operating costs in a broad range of applications. This wide range of technologies provides an interesting challenge when trying to find the best series of unit operations to address an application. This is particularly true in view of the need to treat feed waters that widely vary in contaminants and cost in different locations around the world. When considering environmental factors such as water conservation, wastewater reduction and when including infrastructure and labor costs in the evaluation, the analysis of the project can become complex and time consuming. To address these issue for one specific application: the production of boiler feed water, we have developed a range of tools that allow for a quick but thorough evaluation of key factors for both new projects as well as system upgrades. These tools allow evaluation of Pretreatment options, Softening, Ion Exchange (IX), Ultrafiltration (UF), Reverse Osmosis (RO), Electrodialysis Reversal (EDR), Electrodeionization (EDI) and Thermal Evaporation and various combinations thereof. In this paper the capital and operating costs of several combinations of these unit operations are compared. The product water in all cases is high purity water to feed a high-pressure boiler or to be directly injected into a gas turbine. The tools are designed to be used in the planning stage of a new project or system upgrade. Starting with a range of key inputs and assumptions they provide detailed information on capital and operational costs. A payback time is calculated for a system upgrade with limited input data being required. For new systems the tools provide a comprehensive comparison of alternative system designs, without the need for a detailed design of each option. Early in the process it will become clear which technologies are most attractive, depending on the feed water analysis and sitespecific factors, including input costs, and operating conditions. The result allows the utility manager or application engineer to come to a comprehensive and definitive conclusion in a matter of hours. The tools that we have developed include: 1. Addition of a RO unit to an existing Softener, to feed a low- or medium-pressure boiler. 2. Addition of a RO unit in front of an existing conventional Demin system using Ion Exchange technology, to feed a medium- or high-pressure boiler. 3. UF plus RO to replace an existing Hot Lime Softener, to feed a medium- or highpressure boiler. 4. RO plus EDI versus Ion Exchange, to produce high purity water to feed a highpressure boiler. Find a contact near you by visiting www.ge.com/water and clicking on Contact Us. * Trademark of General Electric Company; may be registered in one or more countries. 2008, General Electric Company. All rights reserved. TP1165EN.doc Jun-08

Assumptions This paper will focus on the last tool: RO plus EDI versus IX for new projects. Life cycle costs of various combinations of these technologies will be evaluated. A sensitivity study is carried out to determine the precise effect of feed and waste water cost, feed water salinity (TDS), energy, and chemical (caustic) costs on the total cost to produce high purity water. The tool provides guidance as to what combination of technologies is most attractive for a new boiler feed water project. While economic comparisons between membrane technology and ion exchange have been conducted in various papers [1-3], most of these comparisons date back 5 to 10 years. Changes in chemical and water costs, and new technical developments in low energy membranes and more efficient IX, and addition of new technologies such as EDI, make it necessary to update and expand these comparisons. In this evaluation, typical North American and European designs, feed waters, and input costs have been used. Pretreatment to the RO or IX systems is not considered, as it is assumed that the water has limited suspended solids (SDI < 3) for all system designs. In any case there would be little difference in this pretreatment, so the impact on economics is modest. Of course, the addition of an ultrafiltration system, clarifier or multi media filter must be considered if the feed water has a high fouling potential. This paper is focused on the demineralization steps. System Design All designs are assumed to contain industrial grade equipment using a conservative design philosophy. In all cases, multiple trains are considered with an N+1 redundancy for the IX systems. The RO and E- Cell* EDI systems are designed with a minimum flow rate of 2 x 80% design flow for the smaller flows and N+1 redundancy for the larger flows. Feed water and product water storage are not considered. Storage tanks and distribution pumps between unit operations are included, when required. All systems are designed to achieve a final product water quality of < 0.1 µs/cm conductivity with silica and sodium levels each < 10 ppb. Equipment installation and commissioning costs are included in the total capital costs, using a percentage of the total equipment cost. Design 1 is a traditional co-current regenerated ion exchange system. It contains a Strong Acid Cation vessel followed by a Decarbonator to remove CO 2 (when required) and a Strong Base Anion system. Mix Bed ion exchange is used for polishing. Cocurrent flow is the simplest IX design. Resin is regenerated in the same downward direction as the service flow. Design 1: Co-current Ion Exchange (CFR) or Design 2: Counter-current Ion Exchange (RFR) SAC reject Design 2 is similar to Design 1 but with a packed bed, counter-current regenerated ion exchange system. In these systems, regenerant is applied in a direction opposite to the service flow. This has the advantage of providing better water quality, higher chemical efficiency, and reduced wastewater flow (higher water recovery). Most new IX systems are of the counter-current design. For both IX options we applied a safety factor of 0.85 for cation and 0.8 for anion resin to simulate a 5 years operating period. Design 3: Reverse Osmosis + Mixed Bed (RO-MB) reject SBA MB SAC SBA MB SAC SBA Design 3 is a Reverse Osmosis system followed by a Decarbonator (when required) and a MB polishing unit. The RO is equipped with standard medium pressure membrane elements. The mixed bed unit requires a chemical regeneration facility, bulk storage tanks, and neutralization facilities similar to design 1 and 2. High Purity Water High Purity Water Page 2 Technical Paper

Design 4: Softener + Reverse Osmosis + E-Cell Sof-RO-EDI) NaOH Design 6: Double Pass Reverse Osmosis + E-Cell (2RO-EDI) NaOH softener sac reject High Purity Water reject High Purity Water Design 4 is a sodium cycle ion exchange softener (when required) followed by a RO and final polishing by an E-Cell EDI system. Softening the RO feed water results in several advantages for RO operation: reduced fouling, higher recovery, higher specific flux and the option to raise feed ph to reduce CO 2 levels in the permeate. The concentrate of the E-Cell unit is re-circulated back to the front of the RO. Design 5: Reverse Osmosis + Decarbonator + Softener + E-Cell (RO-Sof-EDI) reject softener sac High Purity Water Design 5 is similar to design 4 except that the softener is moved to a position after the RO. Softening the RO feed water requires a considerable amount of salt for softener regeneration if the feed water hardness is high. The softener must be sized to accommodate the full RO feed flow rate. While a softener before the RO results is a stable RO operation, the resulting operating and equipment costs can make RO permeate softening economically more attractive. In design 5 an antiscalant is used to allow RO operation on feed waters containing high hardness and / or silica. If the RO permeate produces a water quality with a total hardness of less than 1 ppm (as CaCO 3 ) there is normally no need for a softener. A Decarbonator or gas transfer membrane unit might need to be added to reduce the level of CO 2 in the E-Cell feed water. Design 6 considers the use of double pass RO. Permeate of the 1 st RO is used to feed the 2 nd RO. Caustic can be dosed between the passes to convert CO 2 to Bicarbonate to reduce the CO 2 level in the 2 nd pass RO permeate. Final polishing is accomplished with an E-Cell unit. The double pass design provides great flexibility in the salinity of the feed water that can be tolerated (i.e. up to 10,000 ppm or higher). Tool Limitations The technology selection tool evaluates all of the above-mentioned options for any given feed water analysis. It is important to point out that it is not a final design tool for each unit operation. The objective of this tool is to help determine which is the most attractive design in terms of capital and operating costs. Once the most attractive design is established, detailed optimization design calculations are required for each unit operation. Default parameters are provided for all input data, based on industry standards. These numbers can be changed to reflect local costs and conditions. The costs for installation and commissioning are expressed as a percentage of the capital cost. For the Base Case, 40% was used for the ion exchange designs and 25% for the membrane designs. These numbers can also be changed to reflect local conditions. Technical Paper Page 3

Feedwater Analysis and Base Case Operating Data Table 1 provides the water analyses used for the comparisons. Case 1 is a low TDS water, at 48.8 ppm as CaCO 3 (0.98 meq/l), which is typical in the Northern parts of Europe or North America. In Case 2 to 5 salinity gradually increases to 488.9 ppm as CaCO 3 (9.78 meq/l). Case 5 could be a typical well water in a coastal area with some seawater intrusion. Case 4, with a feed water TDS of 292.7 ppm as CaCO 3 (5.85 meq/l), is the base water analysis used for the initial evaluations prior to the sensitivity studies. Ion ppm (mg/l) Case 1 Case 2 Case 3 Case 4 Case 5 Ca 7.5 15 30 45 45 Mg 2 4 8 12 12 Na 10 20 40 60 150 Cl 12.7 25.4 50.8 76.2 215.3 SO4 10 20 40 60 60 HCO3 25 50 100 150 150 SiO2 5 10 10 10 10 PH 7.1 7.1 7.1 7.1 7.1 Conductivity mmhos TDS (ppm as CaCO3) TDS (meq/l) TDS (total ppm) 103 206 398 590 918 48.8 97.6 195.2 292.7 488.9 0.98 1.95 3.9 5.85 9.78 72.2 144.4 278.8 413.2 642.3 Table 1: Feed Water Analysis in ppm ion (mg/l), (case 4 is the base case) All other operating conditions for the base case are listed in Table 2. Operating conditions IX- Regenerant dosage H2SO4 (100%) NaOH (100%) Co-current (CFR) 6 lb/ft 3 5 lb/ft 3 Counter-current (RFR) 5 lb/ft 3 4 lb/ft 3 Mixed Bed 8 lb/ft 3 8 lb/ft 3 RO Feed Pressure ( psi ) Design 3 (RO one Pass) 230.8 With GE PRO membranes Design 4 (RO one Pass) 302.8 Includes E-Cell Design 5 (RO one Pass) 230.8 Design 6 (RO two Pass) 253.8 / 390.3 Includes E-Cell Base cost H2SO4 (100%) $0.05 $/lb NaOH (100%) $0.18 $/lb Feed water $0.76 $/Kusg Waste water $0.19 $/Kusg Electricity $0.06 $/KWh Fuel cost $8.50 $/MM BTU Salt cost $0.04 $/lb Equipment Amortization Interest Rate Water Temperature 20 years 7.0% / year 59 o F Table 2: Base Case Operating Conditions In addition to the Capital Expenditures (Capex) and Operating Expenses (Opex) the tool allows the user to estimate and enter various cost savings that are site-specific. Several of these potential savings are listed in table 3. The tool starts with estimates for these site-specific savings that can be adjusted. For the Base Case savings for the membrane designs versus the IX designs are shown in Table 3. Sitespecific savings may be taken into account when calculating the overall cost to produce water. Data is provided with and without these site-specific savings. Page 4 Technical Paper

Capital Cost Estimated Site Specific Saving Value ($) Smaller building size in foot print and height 176,115 Reduced commissioning time required 17,612 No contamination dikes required around chemical storage Environmental reporting of chemicals eliminated or reduced 14,089 5,00 Results of comparison Fig. 1 shows the capital plus installation costs for the various designs listed above, at a flow rate of 440 usgpm using the base case operating conditions listed in table 1 and 2. For the membrane options the capital site-specific savings from table 3 are shown. Significant reductions can be obtained if site-specific savings exist. Truck chemical loading station and dedicated drains with pump to neutralization system are eliminated Acid and Caustic proof concrete, tiles, grout etc. not required 16907 9,862 2,000,000 Site specific savings on Capital & Installation Net Capital & Installation cost Total 239,585 Operating Cost - Estimated Site Specific Saving Value ($) Cation, resin cleaners will not be required 5,520 Anion, resin cleaners and or brine squeeze will not be required Neutralization tank associated problems eliminated More consistent water quality, reduced chance for silica breakthrough, resulting is less scaling in boiler and/or turbine 4,590 3,000 8,806 Cost ( $ ) 1,750,000 1,500,000 1,250,000 1,000,000 750,000 500,000 250,000 0 1 2 3 4 5 6 Design Figure 1: Capital and Installation Cost for Base Case Safety improvements for Operators, Reduction in hazardous chemicals Reduce damage / maintenance due to corrosion from acid fumes Maintenance cost reduction on demin system, valves, pumps, others 5,000 2,000 8,806 Fig. 2 shows the annual operating cost for the same system designs. Equipment financing cost are included and site-specific savings for capital and operation are shown. Labor savings in possible personnel reallocation 44,029 Total 81,480 Annualized Site specific savings on Operation Annualized Site specific savings on Capital & Inst. Annual financing cost Net annual operating cost Table 3: Estimated Site Specific saving, Membrane versus IX design The system flow rates that have been evaluated are 110, 242, 440, 1100 and 2642 usgpm, which cover the flow rate of most industrial boiler systems. The flow rate of 440 usgpm is used for the sensitivity analysis. Cost ( $ ) 900,000 800,000 700,000 600,000 500,000 400,000 300,000 200,000 100,000 0 1 2 3 4 5 6 Design Figure 2: Annual Operating Cost for Base Case Technical Paper Page 5

Fig. 3 shows the cost per produced 1,000 usg (Kusg) of high purity water. For the base case with relatively high TDS of 293 ppm as CaCO 3 (5.85 meq/l), the membrane designs (3 to 6) show a lower cost than the ion exchange designs 1 and 2. Option 3 (RO+MB) shows the lowest cost when site-specific savings are not credited. If site-specific savings are taken into account option 4 and 5 become more attractive. For option 3 the total site-specific savings add up to $0.27 per Kusg and for option 4 to 6 the figure is $0.45 per Kusg. Cost ($/1000 usg) 4.00 3.50 1.50 1.00 0.50 0.00 Annualized Site specific savings on Capital & Inst. Annualized Site specific savings on Operation Net annual operating cost 1 2 3 4 5 6 Design Fig. 3: Produced water cost per Kusg for base case Fig. 4 provides a detailed breakdown of the total cost to produce water. Water cost includes the feed water plus the cost to dispose of the wastewater. For the IX options, the chemicals cost includes the acid and caustic for regeneration, plus the cost for neutralization and resin cleaning. Energy cost includes the pressure for the booster pumps, the decarbonator fan and the heating of the caustic solution. The equipment consumables are the cost of resin replacement. For the membrane designs, the cost for chemicals include caustic dosing, antiscalant, de-chlorination, softener salt and RO cleaning chemicals. The equipment consumables costs include the replacement costs for cartridge filters, RO elements and E-Cell stacks. Energy costs includes the decarbonator fan, high pressure pumps for the RO and booster pumps. Site-specific savings are not included in this breakdown. Note that in all of the following information, site-specific savings are no longer included unless mentioned otherwise. Cost ($/1000 usg) 4.00 3.50 1.50 1.00 0.50 0.00 Water Energy Annualized Equipment Chemicals 1 2 3 4 5 6 Design Fig. 4: Cost breakdown $/1000 Kusg Equipment consumables The base case assumes a relatively low water and waster water cost of $0.76/1000 usg and $0.19 /1000 usg respectively. Despite this low water cost it represents a significant portion of the overall cost in all cases. For the IX designs water cost is lower due to the higher recovery compared to the membrane designs. Energy consumption is higher for the membrane designs but chemicals consumption is lower compared to the IX designs. Figs. 5 to 7 show the capital and operating cost numbers for the base case TDS of 293 ppm as CaCO 3 (5.85 meq/l). Fig. 5 shows the effect of system flow rate. Note the effect on operating cost is quite small for all system designs. $/1000 usg 3.50 1. 50 1. 0 0 0.50 0.00 Design 1 Design 2 Design 3 Design 4 Design 5 Design 6 110 2 4 2 4 4 0 110 1 2 6 4 2 Flowrate usgpm Fig. 5: Operating cost - $/1000 usg Page 6 Technical Paper

On the other hand, the capital cost per installed usgpm declines when the flow rate increases as is shown in Fig. 6. This effect is more pronounced for the IX designs. The reason is that the cost of the peripheral equipment for IX is not very depended on the flow rate and the cost of the IX vessels per installed usgpm declines significantly with increasing vessel diameter. For the membrane options, the cost is more linear with flow rate. $ per installed usgpm 15,000 12,000 9,000 6,000 3,000 Design 1 Design 2 Design 3 Design 4 Design 5 Design 6 Fig. 7 shows the combined number of financed (capital with installation) cost and operating cost. $/1000 usg 5.00 4.00 1.0 0 0.00 110 242 440 1101 2642 Flowrate usgpm Fig. 7: Total operating cost $/1000 usg Design 1 Design 2 Design 3 Design 4 Design 5 Design 6 0 110 242 440 1101 2642 Flowrate usgpm Figs. 8 and 9 show the effect of feed water TDS on water cost at the base case of 440 usgpm and at the highest flow rate of 2642 usgpm, respectively. Fig. 6: Capital & Inst. cost per usgpm installed Design 1 Design 2 Design 3 Design 4 Design 5 Design 6 6.00 $/1000 usg 6.00 5.50 5.00 4.50 4.00 3.50 1.5 0 Design 1 Design 2 Design 3 Design 4 Design 5 Design 6 $/1000 usg 5.50 5.00 4.50 4.00 3.50 1.5 0 1.0 0 0.50 0.00 0 50 100 150 200 250 300 350 400 450 500 550 TDS PPM as CaCO 3 1.0 0 0.50 0.00 0 50 100 150 200 250 300 350 400 450 500 550 TDS PPM as CaCO 3 Fig. 9: Cost per 1000 usg versus TDS for 2642 usgpm Fig. 8: Cost per 1000 usg versus TDS for 440 usgpm Technical Paper Page 7

The point at which the membrane designs become more attractive than the IX designs (the cross-over or break-even point) shifts towards higher TDS levels with increasing flow rate. Note the position of the arrows dropping down to the x-axis for the most efficient IX design 2. For the highest cost membrane design 6 (2RO-EDI) the break-even point is at TDS 210 ppm as CaCO 3 (4.2 meq/l) for a 440 usgpm flow rate and at TDS 275 ppm as CaCO 3 (5.5 meq/l) for a 2642 usgpm flow rate. $/1000 usg Design 1 Design 2 Design 3 Design 4 Design 5 Design 6 The break-even points for the different designs also shift relative to each other with increasing flow rate. The reason is that the cost lines are not smooth curves. This is caused by the need for additional equipment at higher feed water TDS levels. At a higher CO 2 level a decarbonator is often needed and a softener might be required when feed water total hardness increases. This additional equipment obviously affects the water cost. Fig. 10 provides a close up view of the membrane options at a flow rate of 110 usgpm. It shows that the membrane options are more attractive for all designs at a TDS levels above 75 ppm as CaCO 3 (1.5 meq/l). Design 4 (softener+ro+e-cell) shows a steep increase in cost between TDS 100 and 200 ppm as CaCO 3 (2 and 4 meq/l) due to the need for a softener equipment and the additional operating cost for salt. Design 5 (RO+softener+E-Cell) requires a softener and decarbonator equipment but the salt consumption is less and therefore the increase is not as steep. As a result design 4 is lowest cost up to TDS of 300 ppm as CaCO 3 (6 meq/l) and design 5 is lowest cost above TDS of 300 ppm (6 meq/l). At a low flow rate the E-Cell options (design 4 and 5) are lower cost than the option with MB (design 3) for the entire TDS range. 1.50 0 50 100 150 200 250 300 350 400 450 500 550 TDS PPM as CACO 3 Fig. 10: Cost per 1000 usg versus TDS for 110 usgpm At higher flow rate this changes as is shown in fig. 11. Above a TDS of 150 ppm as CaCO 3 (3 meq/l) the MB option is more attractive than the E-Cell options at a flow rate of 1100 usgpm. $/1000 usg 1.50 Design 1 Design 2 Design 3 Design 4 Design 5 Design 6 0 50 100 150 200 250 300 350 400 450 500 550 TDS PPM as CACO 3 Fig. 11: Cost per 1000 usg versus TDS for 1100 usgpm Important to realize is that the site-specific savings are not included in any of these graphs. The difference in site-specific savings for design 4 and 5 with design 3 is $0.15/1000 usg for the base case at 1100 usgpm, which would make the net cost of the E-Cell and MB options equivalent at 1100 usgpm. Page 8 Technical Paper

Sensitivity Analysis: Effect of utility costs, chemical costs and membrane selection on produced water cost The previous graphs are all based on the base case operating conditions listed in table 2. The actual cost for electricity, water, wastewater and chemicals will have a significant impact on the final water cost and the break-even point of membrane versus IX options. The cost of NaOH has the largest impact on the chemical cost. The cost of NaOH has more than tripled in most geographies since 2004. The resulting effect on the Ion Exchange options is considerable. Figure 12 shows the result of varying the cost of NaOH from $ 0.18 to 0.36 per lb, for a 100% solution. This represents the current range in NaOH costs worldwide. For comparison, data is provided for the lowest NaOH cost reported in 2004, which was $ 0.045 /lb. The effect of NaOH cost for the membrane options is small. For this reason, and for simplicity only the $ 0.27/lb cost numbers are shown. Comparing the lowest cost IX design 2 with the highest cost membrane design 6 the break-even point ranges from TDS of 135 to 225 ppm as CaCO 3 (2.7 to 4.5 meq/l). For all other membrane designs the break-even point is at TDS 75 ppm as CaCO 3 (1.5 meq/l) or below as is shown in table 4 for a NaOH cost of $ 0.27/lb. In 2004 with caustic pricing at $0.045/lb the breakeven point would have been at TDS of 340 ppm as CaCO 3 (6.8 meq/l) for design 6. This remarkable difference clearly demonstrates that the effect of caustic pricing on the operating cost of an IX system is enormous. This is one of the reasons why there has been a clear shift towards membrane technology during recent years, not only for high TDS waters, but now, for the first time, also for low TDS waters. $/1000 usg 7.00 6.50 6.00 5.50 5.00 4.50 4.00 3.50 1.5 0 1.0 0 0.50 0.00 Design-2- NaOH $0.045/lb Design-2- NaOH $0.27/lb Design-3- NaOH $0.27/lb Design-5- NaOH $0.27/lb Design-2- NaOH $0.18/lb Design-2- NaOH $0.36/lb Design-4- NaOH $0.27/lb Design-6- NaOH $0.27/lb 0 50 100 150 200 250 300 350 400 450 500 550 TDS PPM as CaCO 3 Fig. 12: Effect of NaOH costing on water cost for 440 usgpm Break-even point TDS PPM as CaCO3 NaOH Cost ($/lb) 0.18 0.27 0.36 Design 3 110 75 <50 Design 4 60 <50 <50 Design 5 110 75 50 Design 6 225 160 135 Table 4: Break-even point at varying NaOH cost comparing membrane designs vs. design 2 The cost of electricity has also increased over the last 5 years and this will affect mainly the membrane designs, since they operate at high pressure. The effect of energy is most significant for the double pass RO design 6. Table 5 shows a range of 50 to 160 ppm TDS as CaCO 3 (1.0 to 3.2 meq/l) for design 4 and 5. Technical Paper Page 9

Break-even point TDS PPM as CaCO3 Electricity Cost ($/KWh) 0.04 0.06 0.09 0.12 The break-even point varies from TDS of 180 to 340 ppm as CaCO 3 (3.6 to 6.8 meq/l). The break-even range for the other designs is shown in Table 6. Design 3 95 100 115 135 Design 4 50 60 90 125 Design 5 95 110 135 160 Design 6 160 215 285 310 Table 5: Break-even point at varying electricity cost of membrane designs vs. design 2 Fig. 13 compares design 2 and 6 showing a breakeven range of 160 to 320 ppm TDS as CaCO 3 (3.2 to 6.4 meq/l) for an electricity cost of $ 0.04 to 0.12/kWh. Design 2 Elect. $0.06/kWh Design 6 Elect. $0.06/kWh Design 6 Elect. $0.12/kWh Design 6 Elect. $0.04/kWh Design 6 Elect. $0.09/kWh 5.00 4.50 4.00 3.50 Fig. 14: Effect of Raw Water cost on produced water cost for 440 usgpm flow rate $/1000 usg 1.5 0 1.0 0 0.50 0.00 0 50 100 150 200 250 300 350 400 450 500 550 Break-even point TDS PPM as CaCO3 RW Cost ($/1000 usg) 0.19 0.76 1.89 3.79 Design 3 50 100 160 250 Design 4 <50 70 100 200 Design 5 65 110 185 280 Design 6 180 215 285 340 TDS PPM as CaCO 3 Fig. 13: Effect of Electricity cost on water cost for 440 usgpm flow rate Table 6: Break-even point at varying raw water cost of membrane designs vs. design 2 Fig. 14 provides the cost of produced water with a raw water cost ranging from $ 0.19 to 3.79 / 1000 usg for options 2 and 6. The wastewater cost is kept constant in this graph at the base case value of $ 0.19 / 1000 usg. The impact of the waste water cost is less dramatic on the produced water cost than the raw water cost but if both the raw water cost and waste water cost increase simultaneously the effect is large as is shown in fig. 15. The membrane options operate at a lower recovery than the IX options and therefore the impact of an increase in raw water cost is more pronounced for the membrane options. Page 10 Technical Paper

Fig. 16 compares design 3 (RO+MB) and 4 (Softener+RO+E-Cell). Up to a TDS of 225 ppm as CaCO 3 (4.5 meq/l) design 4 with PRO HR is more attractive than the other designs. The main reason is that the softener is not required up to this TDS due to the higher rejection of hardness. The reduction in capital cost and reduced salt consumption make up for the increased energy cost. Above TDS of 225 ppm as CaCO 3 (4.5 meq/l) PRO HR in combination with design 3 is most attractive. Fig. 15: Effect of Raw Water and Wastewater cost on produced water cost for 440 usgpm flow rate Table 7 shows a TDS range of 170 to 400 ppm as CaCO 3 (3.4 to 8.0 meq/l) comparing design 2 and 6. In this range the increase in energy consumption of the PRO HR makes up for the reduced regeneration chemical requirement of the polishing MB. The break even point for all membrane types is less than 105 ppm (2.1 meq/l) when comparing to design 2. The design 4 with the PRO-LE membrane is shown as a dotted line above a TDS of 300 ppm (6 meq/l) because the RO product water quality at this point is no longer acceptable to the E-Cell unit. 2.30 Break-even point TDS PPM as CaCO3 RW + WW Cost ($/1000 usg) 0.19 0.764 1.89 3.79 Design 3 50 135 245 320 Design 4 <50 100 175 290 Design 5 60 150 265 340 Design 6 170 265 340 400 $/1000 usg 2.10 1.90 1.70 0 50 100 150 200 250 300 350 400 450 500 550 TDS PPM as CaCO 3 Design 3 - PRO Design 3 - PRO LE Design 3 - PRO HR Design 4 - PRO Design 4 - PRO LE Design 4 - PRO HR Design 2 Table 7: Break-even point at varying raw water and wastewater cost of membrane designs vs. design 2 Fig. 16: Effect of membrane selection on produced water cost for 440 usgpm flow rate The final parameter analyzed is the selection of the membrane type in the RO. The base case is using GE PRO elements, which are medium operating pressure, and medium rejection elements. A comparison was made with PRO LE elements, operating at lower pressure and lower rejection and PRO HR elements operating at higher pressure and higher rejection. Technical Paper Page 11

Break-even point TDS PPM as CaCO3 Conclusions Membrane Type PRO LE HR Design 3 105 90 95 Design 4 60 20 55 Design 5 110 85 105 Design 6 215 150 200 Table 8: Break-even point at different RO membrane types of membrane designs vs. design 2 In Fig. 17 both membrane type and electricity cost are varied for design 2 and 6. As expected the effect of energy cost is less pronounced in design 6 for the PRO-LE membrane. In a double pass RO arrangement this membrane is preferred over the PRO element. The average savings using PRO-LE over PRO add up to $ 0.284 / 1000 usg at an electricity cost of $ 0.06 kwh and to $ 0.57 / 1000 usg at an electricity cost of $ 0.12 / kwh. The water quality out of a PRO-LE double pass RO is acceptable for the E-Cell over the entire TDS range that was evaluated. $/1000 usg Design 6 - PRO - Electr. $ 0.06/kWh 5.00 Design 6 - PRO LE - Electr. $ 0.06/kWh 4.50 4.00 3.50 Design 2 - Electr. $ 0.06/kWh 1.50 0 50 100 150 200 250 300 350 400 450 500 550 TDS PPM as CaCO 3 Design 2 - Electr $ 0.12/kWh Design 6 - PRO - Electr. $ 0.12/kWh Design 6 - PRO LE - Electr. $ 0.12/kWh Fig. 17: Effect of membrane selection and electricity cost on produced water cost for 440 usgpm flow rate Important to realize is that Figs. 16 and 17 only apply to a flow rate of 400 usgpm and the base cost for water, waste water and NaOH. If additional parameters are varied, the conclusion as to which design is most attractive might change. 1. Selection of the right technology to produce a high purity boiler feed water requires careful analysis of all the parameters affecting capital and operating costs. 2. It has always been helpful to develop rules of thumb to guide engineers in the choice between membrane- and ion exchange-based demineralization systems. In the last 5 years this has become increasingly difficult. Due to the availability of many new products and design options, and because of radically higher energy, chemical and water costs, the old rules of thumb no longer apply. 3. Conditions favorable for the membrane designs are: High feed water TDS Low product water flow High chemical costs (particularly NaOH) Low water and wastewater costs Low electricity cost. 4. If one or more of the last 4 conditions apply, the break-even point favoring the membrane designs versus ion exchange could be as low as TDS of approx. 50 ppm as CaCO 3 (1.0 meq/l) or 100 µs/cm conductivity. 5. For the TDS range and parameters that were evaluated, membrane options are always more attractive than ion exchange above a TDS of approx. 400 ppm as CaCO 3 (8 meq/l) or 750 µs/cm conductivity. 6. Below 400 ppm (8 meq/l) a detailed analysis is often required. This can only be achieved using a tool that considers all parameters. 7. Site-specific savings can play an important role in technology selection. These savings generally favor membrane options. 8. The use of high rejection RO membrane elements is attractive if they allow operation of the E-Cell EDI designs without a softener. In a double pass RO design, use of low energy Page 12 Technical Paper

membranes provide the lowest produced water cost. 9. In all membrane designs it is important to optimize recovery since water and wastewater costs are significant. In this analysis design 4 (Softener+RO+E-Cell) provides the lowest cost in most situations due to the ability to operate at higher recovery. 10. Water conditioning manual, Dowex ion exchange resins, 1985 11. Kunin Robert, Amber-hi-lites Fifty years of ion exchange technology, Tall Oaks Publishing Inc., 1996 12. Paul Tan, Optimizing a high-purity water system, Tall Oaks Publishing Inc., 2007 10. The use of E-Cell EDI technology after RO is attractive versus Mixed Bed at most flow rates. When site-specific savings apply the membrane options with E-Cell produce the lowest cost water at flow rates from 110-1100 usgpm and above. References 1. P.A. Newell, S.P. Wrigley, P. Sehn and S.S. Whipple, An Economic Comparison of Reverse Osmosis and Ion Exchange in Europe, Ion Exchange Developments and Applications, p. 58-66, Proceedings of IEX 96, Royal Society of Chemistry 2. S. Whipple, E. Ebach and S. Beardsley, UltraPure Water, October 1987 3. Beardsley, S., Coker, S., and Whipple, S., The Economocs of Reverse Osmosis and Ion Exchange, paper presented at WATERTECH 94, Nov 9-11, 1994 4. Rohm and Haas, IXCalc Ion Exchange Design Software 5. Owens DL, Practical Principals of Ion Exchange water treatment, Tall Oaks Publishing Inc., 1985 6. BetzDearborn Handbook of Industrial Water Conditioning, 9 th edition 1991 7. R. Gerard, H. Hachisuka, M. Hirose, Desalination 119 (1998) 47-55 8. Strathmann H., Membrane and Membrane Separation Processes Ellmann s Encyclopedia of Industrial Chemistry, (2005), http://mrw.intersience.wiley.com [2008-2-15] 9. Bornak W, Ion Exchange deionization for industrial users, Tall Oaks Publishing Inc., 2003 Technical Paper Page 13

GE Water & Process Technologies Apendix A: Technology Selection Tool Printout for Base Case Raw water analysis Fill in yellow cells Select the unit system you want to use: 1 1=US, 2=Metric Euro, 3= Metric $ Water source City Equipment selection for Demin system, Mixed Bed, RO, Softener & E-Cell PPM PPM / mg/l meq/l System criteria ions mg/l ion as CACO 3 Please enter the average High Purity Water Production 440.3 usgpm Calcium 45.00 112.5 2.25 The system calculation takes into account that one unit is always on standby Magnesium 1 49.4 0.99 ( Demin train, Mixed bed, Softener, RO & E-cell ) Sodium 60.00 130.80 2.62 A decarbonator will be selected if flow > 99 usgpm and M alk (as CaCO3) > 59 ppm Potassium 0.00 0 0.00 Decarbonator will be in place? 1 1 = Yes, 0 = No Type 1 Iron Fe +2 0.00 0.00 0.00 Regeneration effluent will be neutralised? 1 1 = Yes, 0 = No Mangenese Mn +2 0.00 0.00 0.00 What kind of acid will be used? 2 1 = HCl, 2 = H 2 SO 4 Lead 0 0.00 0.00 Demin system: capacity based on Rohm & Haas resin SAC IR1200, SBA IRA4200 Barium 0 0.00 0.00 Regenerants dosage CFR Acid 6.0 lb/ft3 Caustic 5.0 lb/ft3 Strontium 0 0.00 0.00 Regenerants dosage RFR Acid 5.0 lb/ft3 Caustic 4.0 lb/ft3 Aluminium 0 0.00 0.00 Regenerants pricing Acid 0.05 $/lb Caustic 0.18 $/lb Chloride 76.2 107.40 2.15 Resin life expectation Cations 6 years Anions 4 years Sulfate 60.0 62.36 1.25 Water cost Raw water 0.76 $/Kusg Waste 0.19 $/Kusg HCO 3 - M Alkalinity 150.0 123.0 2.46 Safety factor for resin capacity SAC 0.85 SBA 0.80 Fluoride 0.00 0.00 0.00 Mixed Beds system : Nitrate 0.00 0.00 0.00 Regenerants dosage Acid 8.0 lb/ft3 Caustic 8.0 lb/ft3 ph 7.10 Resin life expectation Cations 5 years Anions 5 years Silica 10.00 8.30 0.17 Equipment Ammortization Period, months 240 Interest Rate, % 7% CO 2 19.49 22.21 0.44 Equipment installation cost express as % of capital cost Demin 40% RO + EDI 25% Calculated TDS 413.12 RO to MB or Softener one pass % Recovery 75% PSI increase 230.80 psi Conductivity mmhos 590 Softener to RO - one pass % Recovery 85% PSI increase 302.80 psi TOC - ppm 1.10 Two pass - RO - fisrt pass % Recovery 75% PSI increase 253.80 psi NTU - Turbidity 1.2 Two pass - RO - second pass % Recovery 85% PSI increase 390.35 psi TSS - ppm 1.0 Select the type of RO membranes to be used 1 Pro RO 365 Pump efficiency % 65% Total Cation 292.720 5.85 AVERAGE water temperature 59.0 F Motor efficiency % 95% Total Anion 292.708 5.85 Anion regen, energy cost Fuel Cost, $/MM BTU 8.50 Electricity cost 0.06 $/Kwh Charge balance Adjusted Chloride value to be enter in cell C20 TEC TEA Capital & Operating Cost evaluation RO-EDI versus Demin - Mixed bed 0.00% MK-3 System Parameters E-cell Energy consum. 1-Pass 0.760 KWh/Kusg 76.18 Stack life expectation 7 years Energy consum. 2-Pass 0.380 KWh/Kusg 292.720 5.85 Rectifier efficiency % 70% 40% - 95% Target Resistivity (Mohm.cm) 324.322 6.49 Rectifier DC output (Volts) 300 300 or 400 VDC 10 1-18 MW cm Annual Operating cost Annual Capital cost + including project cost & Operating $/1000 usg installation cost Options Systems financing cost only produced Option -1- Conventional demin system ( CFR ) follow by mixed bed 1,981,300 $ 847,100 $ 662,800 3.66 $ Option -2- Amberpack demin system ( RFR ) follow by mixed bed 1,949,500 $ 729,400 $ 548,000 3.15 $ Option -3- RO system ( 1 Pass ) followed by Mixed Bed 1,347,000 $ 515,800 $ 390,500 2.23 $ Option -4- Softener - RO system ( 1 Pass ) followed by E-cell 1,100,300 $ 538,900 $ 436,500 2.33 $ Option -5- RO system ( 1 Pass ) - Softener followed by E-cell 1,152,900 $ 537,500 $ 430,200 2.32 $ Option -6- RO two pass system followed by E-cell 1,347,000 $ 651,360 $ 526,060 2.81 $ Option # colored in red : This option is not recommended, ( TDS going into the E-Cell is too high ) Including the site specific savings impact on Capital & Operating Cost Annual Operating cost Annual Capital cost + including project cost & Operating $/1000 usg installation cost Options Systems financing cost only produced Option -1- Conventional demin system ( CFR ) follow by mixed bed 1,981,300 $ 847,100 $ 662,800 3.66 $ Option -2- Amberpack demin system ( RFR ) follow by mixed bed 1,949,500 $ 729,400 $ 548,000 3.15 $ Option -3- RO system ( 1 Pass ) followed by Mixed Bed 1,299,083 $ 454,304 $ 333,464 1.96 $ Option -4- Softener - RO system ( 1 Pass ) followed by E-cell 860,715 $ 435,120 $ 355,020 1.88 $ Option -5- RO system ( 1 Pass ) - Softener followed by E-cell 913,315 $ 433,720 $ 348,720 1.87 $ Option -6- RO two pass system followed by E-cell 1,107,415 $ 547,580 $ 444,580 2.37 $ Page 14 Technical Paper

Capital & Operating Cost evaluation RO-EDI versus Demin - Mixed bed Option -1- Option -2- Option -3- Option -4- Option -5- Option -6- Systems Conventional demin system ( CFR ) follow by mixed bed Amberpack demin system ( RFR ) follow by mixed bed RO system ( 1 Pass ) followed by Mixed Bed Softener - RO system ( 1 Pass ) followed by E-cell RO system ( 1 Pass ) - Softener followed by E-cell RO two pass system followed by E-cell Capital & Installation cost with site specific savings included Reduced Capital & Inst. cost Site specific savings on Capital & Inst. 2,500,000 2,000,000 1,500,000 1,000,000 500,000 0 1 2 3 4 5 6 Options 900,000 Annual operating cost with site specific savings included Net annual operating cost Annual financing cost Annualized Site specific savings on Capital & Inst. Annualized Site specific savings on Operation 800,000 700,000 600,000 500,000 400,000 300,000 200,000 100,000 0 1 2 3 4 5 6 Options Cost to produce high purity water cost/1000 usg or cost/m3 Net operating cost Annualized Site specific savings on Operation Annualized Site specific savings on Capital & Inst. 4.00 3.50 1.50 1.00 0.50 0.00 1 2 3 4 5 6 Options Technical Paper Page 15

Capital & Operating Cost evaluation RO-EDI versus Demin - Mixed bed Systems Option -1- Conventional demin system ( CFR ) follow by mixed bed Option -2- Amberpack demin system ( RFR ) follow by mixed bed Option -3- RO system ( 1 Pass ) followed by Mixed Bed Option -4- Softener - RO system ( 1 Pass ) followed by E-cell Option -5- RO system ( 1 Pass ) - Softener followed by E-cell Option -6- RO two pass system followed by E-cell Annual Operating Cost Breakdown express as cost/1000usg or cost/m3 Water Chemicals Energy Equipment consumables Annualized Equipment 4.00 3.50 1.50 1.00 0.50 0.00 1 2 3 4 5 6 Options Annual Operating Cost Repartition 50.0% 45.0% 40.0% 35.0% 30.0% 25.0% 20.0% 15.0% 10.0% 5.0% 0.0% 1 2 3 4 5 6 Water 26.2% 27.8% 48.7% 43.2% 47.9% 41.5% Chemicals 40.8% 35.0% 9.1% 10.6% 5.3% 6.3% Energy 8.4% 9.2% 13.5% 16.1% 16.0% 24.9% Equipment consumables 3.1% 3.4% 4.5% 11.1% 10.9% 8.1% Annualized Equipment 21.5% 24.5% 24.3% 19.0% 20.0% 19.2% Page 16 Technical Paper

Option -1- Conventional demin system ( CFR ) follow by mixed bed Treated Decarbonator Water Tank 540.9 PRO-FDD-60 PRE High Purity usgpm 1 Water produced 3 3 441.6 usgpm 3 440.3 usgpm MB SAC SAC SBA SBA-CFR-72-S PRO-MB-60-S SBA SAC-CFR-96-S 18.4% 0.29% 99.4 100.6 18.61% 1.29 Reject usgpm Reject Total usgpm usgpm Reject Equipment selection Capital cost Annual Operating cost Cost $/1000 usg produced Demin system # of units Cost Water cost 225,300 $ 0.974 $ -raw water 215,300 $ 0.930 $ SAC-CFR-96-S 3 335,200 $ -Waste water 10,000 $ 0.043 $ PRO-FDD-60 PRE Decarbonator 1 46,100 $ Treated water pumps electricity 18,100 $ 0.078 $ SBA-CFR-72-S 3 298,400 $ DM-Regenerant (acid & caustic) 332,200 $ 1.436 $ Anion regeneration Energy cost 40,100 $ 0.173 $ Acid & caustic pumps skid 2 144,400 $ Demin-Neutralization cost Caustic 0 $ 0.000 $ Acid & NaOH tanks 2 107,500 $ Demin- Resin replacement 22,300 $ 0.096 $ Neutralisation tank 1 100,000 $ Decarbonator - Electricity 13,900 $ 0.060 $ PLC 1 36,800 $ MB-Regenerant (acid & caustic) 5,800 $ 0.025 $ PRO-MB-60-S 3 333,100 $ MB-Neutralization cost Acid 500 $ 0.002 $ Blower 1 13,700 $ MB - Resin replacement 4,600 $ 0.020 $ Total equipment 1,415,200 $ Total annual operating cost 662,800 $ 2.864 $ Installation cost 566,100 $ Annualized project Equipment Cost 184,300 $ 0.796 $ Total equipment + installation 1,981,300 $ Total annual oper. including Project cost 847,100 $ 3.661 $ All calculations are done pre-tax. No credit is calculated for the decreased tax effect of the depreciation stream. For full accounting of the project, after-tax, consult your customer accounting department for their incremental tax rate and treatment of depreciation. Option -2- Amberpack demin system ( RFR ) follow by mixed bed Decarbonator PRO-FDD-60 PRE 440.9 High Purity 1 usgpm Water produced 3 3 440.3 usgpm AP AP 3 MB SAC SAC SBA SBA SAC-AP-72-S SBA-AP-60-S PRO-MB-60-S Treated 501.9 12.1% Reject total 0.15% Water Tank usgpm 61.0 61.6 12.28% 0.64 Reject usgpm Reject Total usgpm usgpm Reject Equipment selection Capital cost Annual Operating cost Cost $/1000 usg produced Demin system # of units Cost Water cost 205,800 $ 0.889 $ -raw water 199,700 $ 0.863 $ SAC-AP-72-S 3 294,200 $ -Waste water 6,100 $ 0.026 $ PRO-FDD-60 PRE Decarbonator 1 46,100 $ Treated water pumps electricity 16,800 $ 0.073 $ SBA-AP-60-S 3 279,500 $ DM-Regenerant (acid & caustic) 245,300 $ 1.060 $ Anion regeneration Energy cost 37,400 $ 0.162 $ Acid & caustic pumps skid 2 131,700 $ Demin-Neutralization cost Acid 700 $ 0.003 $ Acid & NaOH tanks 2 107,500 $ Demin- Resin replacement 20,400 $ 0.088 $ Resin BackWash Tank 2 64,900 $ Decarbonator pump - Electricity 13,900 $ 0.060 $ Neutralisation tank 1 85,000 $ MB-Regenerant (acid & caustic) 2,900 $ 0.013 $ PLC 1 36,800 $ MB-Neutralization cost Acid 200 $ 0.001 $ PRO-MB-60-S 3 333,100 $ MB - Resin replacement 4,600 $ 0.020 $ Blower 1 13,700 $ Total equipment 1,392,500 $ Total annual operating cost 548,000 $ 2.368 $ Installation cost 557,000 $ Annualized project Equipment Cost 181,400 $ 0.784 $ Total equipment + installation 1,949,500 $ Total annual oper. including Project cost 729,400 $ 3.152 $ All calculations are done pre-tax. No credit is calculated for the decreased tax effect of the depreciation stream. For full accounting of the project, after-tax, consult your customer accounting department for their incremental tax rate and treatment of depreciation. Technical Paper Page 17

Option -3- RO system ( 1 Pass ) followed by Mixed Bed 444.5 High Purity # of units 2 444.5 usgpm usgpm Water produced PRO-300 Permeate PRO-FDD-60 PRE 3 440.3 usgpm Treated 1 Water Tank PRO-MB-60-S 592.7 0.97% usgpm 4.26 % Recovery Reject 25% usgpm Reject to waste RO pressure 230.80 75% 148.2 usgpm Decarbonator 152.44 Total Reject RO + MB psi RO reject to waste 25.7% Equipment selection Capital cost Annual Operating cost Cost $/1000 usg produced RO system # of units Cost Water cost 251,100 $ 1.085 $ -raw water 235,900 $ 1.019 $ Chemical injection skid ( 2 products ) 1 8,000 $ -Waste water 15,200 $ 0.066 $ PRO-300 2 306,300 $ Treated water pumps electricity 8,800 $ 0.038 $ CIP skid for RO cleaning 1 9,400 $ RO Power Cost (electricity) 50,800 $ 0.220 $ PRO-FDD-60 PRE Decarbonator 1 46,100 $ RO chemicals cost (antiscalant + dechlore) 19,000 $ 0.082 $ PRO-MB-60-S 3 333,100 $ Membranes chemical cleaning cost 6,000 $ 0.026 $ Acid & caustic pumps skid 2 131,700 $ Membranes replacement cost 13,000 $ 0.056 $ Acid & NaOH tanks 2 107,500 $ Cartridge filters replacement 5,500 $ 0.024 $ Neutralisation tank 1 85,000 $ Decarbonator pump electricity 9,900 $ 0.043 $ PLC 1 36,800 $ MB-Regenerant (acid & caustic) 19,200 $ 0.083 $ Blower 1 13,700 $ MB-Neutralization cost Acid 2,600 $ 0.011 $ Total equipment 1,077,600 $ MB - Resin replacement 4,600 $ 0.020 $ Installation cost 269,400 $ Total annual operating cost 390,500 $ 1.687 $ Total equipment + installation 1,347,000 $ Annualized project Equipment Cost 125,300 $ 0.541 $ Total annual oper. including Project cost 515,800 $ 2.229 $ MB SAC SBA All calculations are done pre-tax. No credit is calculated for the decreased tax effect of the depreciation stream. For full accounting of the project, after-tax, consult your customer accounting department for their incremental tax rate and treatment of depreciation. Treated Water Tank Option -4- Softener - RO system ( 1 Pass ) followed by E-cell 556.4 usgpm 463.5 High Purity 3 # of units 2 463.5 usgpm usgpm Water produced softener S84-VN-S PRO-300 Permeate 440.3 usgpm sac NaOH inj. Recirc. 2 Conc. GEMK3-24 3.0% 531.3 13.90 % Reject usgpm usgpm 9.27 25.1 % Recovery Reject 15% usgpm Reject electrolyte to waste usgpm RO pressure 302.80 85% 81.8 usgpm 116.16 Total Reject Softener + RO + E-Cell 4.5% psi RO reject to waste 20.9% 13.90 usgpm Equipment selection Capital cost Annual Operating cost Cost $/1000 usg produced Softener # of units Cost Water cost 233,000 $ 1.007 $ S84-VN-S 3 123,700 $ -raw water 221,400 $ 0.957 $ -Waste water 11,600 $ 0.050 $ RO system Treated water pumps electricity 14,500 $ 0.063 $ Chemical injection skid ( 2 products ) 1 8,000 $ Softener Salt cost 29,300 $ 0.127 $ caustic pump skid 1 4,000 $ Softener- Resin replacement 3,500 $ 0.015 $ PRO-300 2 306,300 $ RO- Caustic injection cost 8,700 $ 0.038 $ CIP skid for RO cleaning 1 9,400 $ RO Power Cost 61,400 $ 0.265 $ RO chemicals cost (antiscalant + dechlore) 13,300 $ 0.057 $ E-Cell Membranes chemical cleaning cost 6,000 $ 0.026 $ GEMK3-24 2 428,800 $ Membranes replacement cost 13,000 $ 0.056 $ Cartridge filters replacement 5,500 $ 0.024 $ Total equipment 880,200 $ E-Cell Power Cost 10,600 $ 0.046 $ Installation cost 220,100 $ E-Cell replacement Cost 37,700 $ 0.163 $ Total equipment + installation 1,100,300 $ Total annual operating cost 436,500 $ 1.886 $ Annualized project Equipment Cost 102,400 $ 0.442 $ Total annual oper. including Project cost 538,900 $ 2.329 $ All calculations are done pre-tax. No credit is calculated for the decreased tax effect of the depreciation stream. For full accounting of the project, after-tax, consult your customer accounting department for their incremental tax rate and treatment of depreciation. Page 18 Technical Paper

Option -5- RO system ( 1 Pass ) - Softener followed by E-cell PRO-300 463.5 High Purity Treated # of units 464.4 usgpm usgpm Water produced Water Tank 2 Permeate 440.3 usgpm 605.3 PRO-FDD-60 PRE 3 Recirc. 2 usgpm 1 softener Conc. GEMK3-24 sac 3.0% 13.90 % Reject usgpm 9.27 RO in with recirc. % Recovery Reject 25% 0.93 S84-VN-S usgpm Reject electrolyte to waste 619.2 75% 154.8 usgpm Decarbonator usgpm 164.99 Total Reject RO + Softener + E-Cell usgpm RO pressure 230.80 RO reject to waste 0.20% 27.3% psi Equipment selection Capital cost Annual Operating cost Cost $/1000 usg produced RO system # of units Cost Water cost 257,300 $ 1.112 $ -raw water 240,900 $ 1.041 $ Chemical injection skid ( 2 products ) 1 8,000 $ -Waste water 16,400 $ 0.071 $ PRO-300 2 306,300 $ Treated water pumps electricity 9,200 $ 0.040 $ CIP skid for RO cleaning 1 9,400 $ RO Power Cost 53,100 $ 0.229 $ PRO-FDD-60 PRE Decarbonator 1 46,100 $ RO chemicals cost (antiscalant + dechlore) 19,800 $ 0.086 $ Softener Membranes chemical cleaning cost 6,000 $ 0.026 $ S84-VN-S 3 123,700 $ Membranes replacement cost 13,000 $ 0.056 $ E-Cell Cartridge filters replacement 5,500 $ 0.024 $ GEMK3-24 2 428,800 $ Decarbonator pump electricity 12,900 $ 0.056 $ Softener Salt cost 2,700 $ 0.012 $ Softener- Resin replacement 2,400 $ 0.010 $ Total equipment 922,300 $ E-Cell Power Cost 10,600 $ 0.046 $ Installation cost 230,600 $ E-Cell replacement Cost 37,700 $ 0.163 $ Total equipment + installation 1,152,900 $ Total annual operating cost 430,200 $ 1.859 $ Annualized project Equipment Cost 107,300 $ 0.464 $ Total annual oper. including Project cost 537,500 $ 2.323 $ All calculations are done pre-tax. No credit is calculated for the decreased tax effect of the depreciation stream. For full accounting of the project, after-tax, consult your customer accounting department for their incremental tax rate and treatment of depreciation. Option -6- RO two pass system followed by E-cell GE PRO-450-PRE-FRP-60 usgpm GE PRO-300-PRE-FRP-60 usgpm 463.5 High Purity Treated # of units 545.2 # of units 463.5 usgpm Water produced Water Tank 2 Permeate 1 2 Permeate 2 440.3 usgpm 631.3 Recirc. 2 usgpm Conc. GEMK3-15 3.0% 13.90 % First pass Second pass usgpm 9.27 RO in with recirc. % Recovery 25% Reject NaOH inj. % Recovery usgpm Reject electrolyte to waste 727.0 75% 181.7 usgpm 85% 191.02 Total Reject RO + E-Cell usgpm Pump Pressure in 390.35 psi Conc. recir. 15% 30.3% 253.80 RO reject to waste 81.8 usgpm psi Equipment selection Capital cost Annual Operating cost Cost $/1000 usg produced RO system # of units Cost Water cost 270,200 $ 1.168 $ -raw water 251,200 $ 1.085 $ Chemical injection skid ( 2 products ) 1 8,000 $ -Waste water 19,000 $ 0.082 $ First Pass RO Treated water pumps electricity 9,380 $ 0.041 $ GE PRO-450-PRE-FRP-60 2 422,300 $ RO Fisrt pass Power Cost 68,600 $ 0.296 $ caustic pump skid 1 4,000 $ RO Second pass Power Cost 79,100 $ 0.342 $ Second Pass RO RO Power Cost 147,700 $ 0.638 $ GE PRO-300-PRE-FRP-60 2 306,300 $ RO chemicals cost (antiscalant + dechlore) 20,200 $ 0.087 $ CIP skid for RO cleaning 1 10,800 $ RO 2- Caustic injection cost 8,680 $ 0.038 $ E-Cell Membranes chemical cleaning cost 12,100 $ 0.052 $ GEMK3-15 2 326,200 $ Membranes replacement cost 28,700 $ 0.124 $ Cartridge filters replacement 7,300 $ 0.032 $ Total equipment 1,077,600 $ E-Cell Power Cost 5,300 $ 0.023 $ Installation cost 269,400 $ E-Cell replacement Cost 16,500 $ 0.071 $ Total equipment + installation 1,347,000 $ Total annual operating cost 526,060 $ 2.273 $ Annualized project Equipment Cost 125,300 $ 0.541 $ Total annual oper. including Project cost 651,360 $ 2.815 $ All calculations are done pre-tax. No credit is calculated for the decreased tax effect of the depreciation stream. For full accounting of the project, after-tax, consult your customer accounting department for their incremental tax rate and treatment of depreciation. Technical Paper Page 19

Other Benefits of using RO/E-Cell technologies versus Demineralizers that can possibly be translated into Capital Savings Site specific savings, has to be validated by the Customer, all may or may not apply. Value 176,115 Smaller building size in foot print and height 17,612 Reduced commisioning time required 14,089 No contamination dikes required around chemical storage 5,000 Environmental reporting of chemical eliminated 16,907 Truck chemical loading station and dedicated drains with pump to neutralization system are eliminated 0 You can enter here others benefits that are not listed 0 You can enter here others benefits that are not listed 0 You can enter here others benefits that are not listed 0 You can enter here others benefits that are not listed 9,862 Acid and Caustic proof concrete, tiles, grout etc. not required 0 You can enter here others benefits that are not listed 239,585 Total $ claimed for other annual benefits 22300 Other Benefits of using RO-E-Cell technology versus Demineralizers that can possibly be translated into Operating Savings Site specific savings, has to be validated by the Customer, all may or may not apply. Value 5,250 Cation, resin cleaners and or brine squeeze, will not be needed 4,590 Anion, resin cleaners and or brine squeeze, will not be needed anymore 3,000 Neutralization tank associated problems, maintenance cost + time delay 0 More consistent water quality, reduced chance for silica breakthrough resulting is less scaling in boiler or turbine 5,000 Safety improvements for Operators, Reduction in hazardous chemicals 8,806 ecomagination - less "salts" discharged to the environment, no need to desalt downstream!! 0 Value of "bad" regenerations that have to be repeated 2,000 Reduced damage / maintenance due to corrosion from acid fumes 0 You can enter here others benefits that are not listed 8,806 Maintenance cost reduction on demin system, valves, pumps, others 44,029 Labor savings in possible personnel relocation or reallocation 81,480 Total $ claimed for other annual benefits Page 20 Technical Paper