15-6495 Spec - Scope

COLLIER COUNTY NCRWTP MEMBRANE ELEMENTS JUNE 12, 2015 42 32 56A - 1

SECTION 43 32 56A

MEMBRANE ELEMENTS

PART I GENERAL

1.01 GENERAL

A. This Section covers membrane elements to be supplied by the Membrane Element Manufacturer/Supplier (SUPPLIER) under contract to Collier County (COUNTY). The SUPPLIER shall furnish replacement elements for six (6) existing nanofiltration (NF) membrane trains at the North County Regional Water Treatment Plant (NCRWTP) as specified herein.

B. The membrane elements specified herein will be installed and tested by a reputable Membrane System Supplier (INSTALLER) under a separate contract with the COUNTY. The INSTALLER will conduct a membrane performance test to determine conformance with these specifications and will coordinate potential warranty claims with the SUPPLIER.

C. The SUPPLIER shall furnish to the COUNTY all certifications and warranties as specified herein.

D. Patents:

1. The SUPPLIER shall warrant that the use of the membrane furnished membrane elements to be installed in the existing NCRWTP NF process will not infringe on any U.S. or foreign patent recognized by the U.S.

2. The SUPPLIER shall grant to the COUNTY in perpetuity a paid-up license to use any inventions covered by patent or patents pending, owned or controlled by the SUPPLIER in the operation of the facility hereunder, without the right to grant sublicenses.

E. The membrane elements specified herein shall be the end product of one approved SUPPLIER to achieve standardization of performance, operation, spare parts, maintenance and manufacturer’s service.

1.02 DESCRIPTION OF OVERALL TREATMENT PROCESS

A. The existing NCRWTP NF membrane system comprises six membrane trains. Each train contains 56 total pressure vessels with 32 pressure vessels in the first stage, 16 pressure vessels in the second stage, and 8 pressure vessels in the third stage. Each pressure vessel is capable of holding six (6) 8-inch diameter by 40-inch long elements. A total of 336 membrane elements per train and 2,016 membrane elements total will be replaced under this specification.

B. The NF trains are located in the process room of the membrane building at the NCRWTP site. The existing membrane elements are GE MUNI 365 NF membrane elements.


C. Groundwater from Tamiami Aquifer production wells is pumped to the NCRWTP. The well water from several wells is combined into a common supply line that receives pretreatment before entering the membrane trains.

D. Pretreatment processes include 5-micron cartridge filtration and chemical addition (sulfuric acid and scale inhibitor). Pretreated water flows in a common pipeline to the membrane feed pumps.

E. Each membrane train has a dedicated membrane feed pump driven by an adjustable frequency drive (AFD), first stage permeate throttling valve, and automatic concentrate control valve. As part of a simultaneous improvement project, each train will be retrofitted with an interstage booster pump between the second and third stages.

F. The trains are automatically controlled using a programmable logic controller (PLC) based control system. The individual stage permeate and concentrate flow rates (and thus, recovery) of each stage/train are controlled primarily by automatic adjustment of the first-stage permeate and concentrate flow control valves. The new interstage booster pump AFD will be automatically adjusted to maintain a third-stage permeate flow rate. The AFD on the membrane feed pump is automatically adjusted to provide the flow and pressure necessary to maintain total permeate production requirements of the respective train.

G. Permeate from the NF trains is blended with permeate from four RO trains, degasified, chemically treated, stored, and pumped to distribution.

H. Concentrate from each membrane train is piped through a common line from the membrane building into a concentrate wet well under minimal pressure from which the concentrate is then pumped into an injection well.

1.03 MEMBRANE WARRANTY

A. Workmanship and Materials: The SUPPLIER shall warrant that the membrane elements and accessories provided will be free from defects in material and workmanship under normal conditions and are free from liens and encumbrances. Should any defect in material and workmanship be discovered within one year from initial operation of the train (or 18 months from the delivery date, whichever comes first), the SUPPLIER shall provide new replacement membrane elements on a prorated cost basis to restore performance to warranted levels at the design flux and recovery rate.

B. During the initial performance testing period, The SUPPLIER shall provide replacement membrane elements to be installed by the INSTALLER at no cost to the COUNTY to restore performance to warranted levels at the design flux and recovery rate.

C. After the initial performance testing period, The COUNTY’s cost for replacement of each warranted element shall be limited to the Guaranteed Membrane Replacement Price per Element entered in the attached bid form, FOB to the NCRWTP site minus a prorated rebate on the unrealized life of the anticipated minimum 5-year life. The COUNTY shall be responsible for installation labor. The prorated rebates shall be based on 1/60 of the cost per month for each month remaining in the 5-year anticipated element life period calculated from the end of the accepted performance test period.


D. It is understood that the COUNTY is obligated to operate the membrane system within critical operating criteria (submitted by the SUPPLIER prior to initial startup).

1.04 SUBMITTALS

A. Attached bid form including present worth energy cost.

B. At the time of bid, the SUPPLIER shall submit four (4) copies of all submittal information listed in this section in a three-ring notebook and in electronic PDF format on CD. The SUPPLIER shall submit with the bid the following items:

1. Cut-sheets and catalog data for the proposed membrane elements. Submitted information shall include model identification, pressure rating, membrane area, feed spacer thickness, and standard test conditions including test feed pressure, test feed solution information, average and minimum salt rejection and average permeate flow

2. List all critical operating criteria limits including operating pressure, flow, temperature, pH, turbidity, and SDI limits.

3. Computer design WQ membrane performance projections using the design feed water quality criteria specified in Table 1 and the NCRWTP NF system design, as specified herein. Projections shall be made for 0 and 5 years of operation at the design flux, recovery and interstage boost.

4. NSF 61 approval certificate for the proposed membrane elements.

5. Certification that the existing Alkema AWC A-111 scale inhibitor and melt-blown 5-micon nominal rated polypropylene cartridge filter media are appropriate for the provided membrane elements.

6. Provide warranty information including agreement with terms listed above.

7. List of exceptions to this specification.

C. Not required at bid time, but a minimum of one week before shipment of membrane elements to the WTP site, the SUPPLIER shall submit:

1. Standard operations and maintenance information including, installation instructions, cleaning procedures, and storage information. Include pH, temperature and exposure (time) limits for chemical cleaning

2. List of cleaning chemicals that are compatible with the membrane elements provided. The chemicals shall not be proprietary to a single chemical manufacturer. A list of acceptable proprietary chemicals and suppliers may be submitted as a supplement.

3. Date of element manufacture

4. Wet test data for all of the membrane elements conducted at the SUPPLIER’s standard conditions listed on the element data sheet that shows conformance with the criteria in Section 3.02 Membrane Element Performance Criteria.


5. Proposed custom loading schedule showing the pressure vessel and element position of each element serial number in the wet test data. The loading schedule shall include:

a. Average wet test rejection and flow data for the proposed element loading schedule by pressure vessel to show that higher rejection and lower productivity elements will be installed in the first stage and that highest productivity elements will be loaded into the third stage.

b. Balanced flow and rejection by vessel so that the average wet test rejection and flow for an individual pressure vessel is within 15 percent of the average for the stage in which the pressure vessel is installed.

PART II PRODUCTS

2.01 GENERAL

A. The use of manufacturer's model or catalog numbers herein is for the purpose of establishing item quality and configuration desired. Elements by others must be evaluated and approved by the COUNTY before acceptance for use on this Project.

B. All components that come into contact with drinking water or drinking water treatment chemicals shall be in conformance with American National Standards Institute (ANSI)/NSF International (NSF) Standard 61.

C. The SUPPLIER shall be responsible to provide identical membrane elements for each train and shall provide all components required for a membrane installation in the existing vessels as described herein.

2.02 MEMBRANE ELEMENTS

A. The membrane elements shall be thin film composite and be from the listed standard commercial products of a membrane manufacturer that has supplied membrane elements that have been operating for a minimum of 8 years in at least one municipal installation within the state of Florida. The following manufacturers and membrane element types are acceptable (listed in alphabetical order).

1. DOW/FilmTec (NF90-400 and/or NF270-400)

2. GE (AP-400 and/or HL8040F-400)

3. Hydranautics (ESNA1-LF-LD and/or ESNA1-LF2-LD)

4. Koch/Fluid Systems (8040-SR100-400)

5. Other manufacturers and models may be approved by the COUNTY during bidding if they meet the minimum time requirements listed above and the performance criteria specified herein.

B. Nominal 8-inch diameter membrane elements shall be designed to be loaded into 8-inch (nominal) diameter pressure vessels capable of holding six nominal 8-inch diameter x 40-inch long elements and meet the following criteria.


1. The membrane elements shall be spiral wound with the feed and concentrate flow through the element parallel to the central product water tube of the element. Each element shall have nominal dimensions of 8 inches in diameter and 40 inches in length. Elements shall be designed to operate at pressures up to 600 psig minimum. The membrane elements shall be complete with brine seals, interconnectors, O-rings, spacers (shims), and other hardware except end adapters necessary to make the membrane fully compatible with the new Protec or Codeline pressure vessels that will be installed during a simultaneous project. The brine seal and O-rings shall be made of ethylene propylene rubber. The membrane element shall have a fiberglass reinforced plastic outer wrap.

2. The active membrane area of each membrane element shall be 400 square feet

3. The membrane elements shall have a nominal feed-concentrate channel spacer with a thickness of 28 mils or greater.

4. The membrane elements must be NSF 61 certified in accordance with Section 62-555.320 of the Florida Administrative Code

2.03 EXISTING SYSTEM DESIGN

A. The SUPPLIER shall be responsible to provide membrane elements for six (6) trains (2,016 elements total), each with a membrane permeate capacity of 2,000,000 gallons per day for a total capacity of 12,000,000 gallons per day.

B. The proposed membrane elements shall be installed in the existing NCRWTP membrane system with the following design features:

1. Six trains each with 56 “6M” 8-inch diameter pressure vessels, 2.0 mgd permeate capacity each (12.0 mgd total permeate)

2. The trains are configured to act independently of each other.

3. First-stage average flux shall not exceed 17.0 gallons per square foot per day (gfd). Minimum second and third stage average flux shall be 12 gfd.

4. The membrane feed pump AFDs will be controlled by the plant PLC system to maintain the minimum required flow and pressure (up to a design maximum feed pressure of 190 psi) to meet final permeate production.

5. The concentrate flow from each train (and therefore recovery) will be controlled by the concentrate flow control valve located on each train.

6. Raw water parameters and permeate water quality shall conform to the values specified in Table 1. It may be assumed that a phosphonic or organic antiscalant with sulfuric acid will be fed to the raw water as membrane pretreatment.

7. Each train shall have a design recovery of 90 percent.

8. Maximum residual concentrate pressure needed for disposal is 5 psi

9. Use of a hybrid membrane configuration that uses different model elements from the same manufacturer in different stages (maximum of one element type per stage and


two types maximum in a single train) is acceptable to meet the water quality and flux balancing requirements of this specification.

10. First stage permeate throttling is acceptable in order to meet the flux balancing requirements of this specification.

11. Third-stage feed pressure boost may be used to balance/control third-stage flux rate (up to 30 psi of boost pressure at 315 gpm).

12. Total permeate pressure – 18 psi

PART III EXECUTION

3.01 GENERAL

A. The SUPPLIER shall deliver FOB to the NCWRTP site the specified number of elements and accessories in six one-train orders (336 elements each) per the purchase order terms and conditions. Delivery schedule is anticipated to be in 2 to 4 week order intervals over a 3 to 6 month period and shall be coordinated with the INSTALLER.

B. Indicate in writing on the labeling of the box that the membranes are shipped wet and if appropriate, what type of preservative is used.

C. Membrane elements shall not be manufactured more than 6 months prior to delivery to the NCRWTP site.

D. The COUNTY may purchase additional spare membrane elements on an as-needed basis FOB to the NCWRTP site at any time over the one-year contract period at the Guaranteed Membrane Replacement Price per Element as listed in item 2 of the Bid Form. The SUPPLIER shall deliver up to 18 elements within 30 days per request. COUNTY requests for more than 18 elements per 30-day period shall be based on SUPPLIER availability.

E. The membrane elements provided under this Specification shall be complete and operable in all respects including, but not limited to, accessories such as permeate interconnectors and brine seals suitable for installation in the existing nominal 8-inch diameter “6M” pressure vessels.

F. The SUPPLIER shall provide additive alternative pricing above the base membrane element bid price for optional membrane features including interlocking membrane elements, single O-ring interconnectors, and anti-microbial feed/brine spacers if available.

3.02 MEMBRANE ELEMENT PERFORMANCE CRITERIA

A. Each individual train adjusted startup feed pressure shall be less than the guaranteed maximum feed pressure entered in the bid form and used for the present worth cost.

B. Individual stage startup differential pressure shall be less than 25 psi.

C. Produce adjusted total permeate water quality that meets the permeate water quality criteria specified in Table 1 during the 1-year warranty period.


D. The INSTALLER shall conduct a performance acceptance test on behalf of the SUPPLIER upon initial startup of each membrane train fitted with replacement elements. Conformance with this specification will be determined by the following:

1. The INSTALLER shall measure the actual startup feed pressure, differential pressures, permeate pressure, and feed/permeate water quality parameters listed in Table 1 when operating the NF train at the design total permeate flow and recovery after reaching steady state performance after a minimum of 48 hours of operation when conductivity, pressures, and flows have stabilized.

2. Running startup membrane performance projections using the actual feed water quality measured during the performance test when operating at design permeate and concentrate flows.

3. Calculating the adjusted startup feed pressure by multiplying the actual startup feed pressure by the ratio of the projected feed pressures from the 1) startup WQ membrane performance projections and the 2) design WQ membrane performance projections included in the submittal.

4. Calculate the adjusted total permeate water quality by multiplying the actual startup permeate water quality by the ratio of the projected total permeate water qualities from the 1) startup WQ membrane performance projections and the 2) design WQ membrane performance projections included in the submittal.

5. Non-compliance with adjusted startup feed pressure, individual stage startup differential pressure, and/or adjusted total permeate water quality limits will result in a warranty claim unless evidence of particulate fouling (i.e. sand) is visually evident in the lead element of the first stage.

6. The SUPPLIER shall provide new replacement membrane elements at no cost FOB to the NCRWTP site to restore performance to adjusted performance levels at the design membrane train flows

7. The INSTALLER shall conduct pressure vessel permeate conductivity profiling of the membrane trains. If the permeate conductivity of an individual pressure vessel is greater than 20 percent higher than the average permeate conductivity for the stage that contains the pressure vessel, the INSTALLER shall probe the vessel to find the location of the high conductivity source. The SUPPLIER shall replace o-rings or membrane elements at no charge to the COUNTY until the vessel meets this specification.

E. When tested under the SUPPLIER’s published standard test conditions, each individual membrane element shall have a rejection equal to or better than the minimum rejection specified in the membrane element’s product bulletin and shall have permeate flow as stated in the membrane element’s product bulletin for average productivity plus or minus 15 percent. The average rejection and productivity of all supplied membrane elements shall meet or exceed average specifications published in the standard membrane element’s product bulletin when tested at standard test conditions. This will be confirmed using the provided wet test data in Section 1.04.C.


F. The INSTALLER shall collect feed, total permeate, and concentrate water samples and shall have a qualified laboratory, approved by the COUNTY, analyze for water quality parameters not analyzed using onsite instrumentation. All parameters in Table 1 shall be tested for in each sample.

G. In the case of a nonconforming elements, the COUNTY may at its option, withhold final payment to the SUPPLIER until the elements are conforming. If final payment is made with the elements specified herein classified as nonconforming, the provisions of the warranty sections of this Specification shall be in effect, except that the 1-year warranty period shall not commence until the non-conforming elements have been corrected.


TABLE 1: NCRWTP FEED WATER AND PERMEATE QUALITY CRITERIA

Constituent Design Feed Analysis a

Permeate Quality Criteria

Calcium, mg/L 99

Magnesium, mg/L 19

Sodium, mg/L 51 < 160

Potassium, mg/L 5

Strontium, mg/L 0.6

Barium, mg/L 0.014 < 2

Bicarbonate, mg/L 395

Sulfate, mg/L 32 < 250

Chloride, mg/L 62

Nitrate, mg/L as N 0 < 10

Fluoride, mg/L 0.3 < 2.0

Silica, mg/L Reactive 20

TDS, mg/L 483 < 500

pH, units 7.2

Hydrogen Sulfide, mg/L > 1.0

Total Hardness, mg/L as CaCO3 326 50 to 100

Total Alkalinity, mg/L as CaCO3 324 > 50

True Color, PCU 20 < 5

Turbidity, NTU < 0.5

SDI < 3.0

Temperature, Celsius 25.5

Total Organic Carbon 9.3

a Raw water before sulfuric acid and scale inhibitor addition and cartridge filtration

END OF SECTION

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15-6495 Spec - Scope