HomeMy WebLinkAboutSludge Dewatering Polymer Trials (2021) Final
Sludge Dewatering Polymer Trials (2021)
Polymer Supplier Selection 2
Invitation to Bid
The following are the estimated deadlines for polymer manufacturer selection:
□ Distribution of Solicitation Notice: June 13, 2021
□ Manufacturer deadline to submit Notification of Interest: July 8, 2021
□ On-site bench-scale jar test polymer product(s): July 6, 2021 – July 23, 2021
□ On-site full-scale Performance Testing: August 2, 2021 – August 27, 2021
□ Manufacturer deadline to submit formal bids: September 9, 2021
Polymer Testing Protocol
Polymer equipment suppliers and/or polymer manufacturers will be invited by the City of Bozeman,
Montana to participate in prequalification polymer trials. Dewatering trials will be conducted at the
Bozeman Water Reclamation Facility (WRF). Prequalification trials shall consist of (i) bench-scale jar tests
and (ii) full-scale performance tests. Based on the results of the trials, manufacturers whose polymer has
met the performance criteria for this facility will be asked to submit separate sealed bids presenting
their cost to supply the polymer equipment and/or polymer(s) for the facility. Bids from manufactures
for polymers that have not undergone the full-scale performance tests will not be accepted or reviewed.
The City of Bozeman WRF has a location dedicated for blending and feed of polymer from chemical
totes. The polymer feed equipment is a Fluid Dynamics Model #N0203-F110231, modified to now use a
Blue-White Flex-Pro A2F24-MGG peristaltic emulsion pumping unit. This trial will include performance
testing of the polymers dewatering a mix of anaerobically digested primary and secondary biosolids
(sludges) for one (1) Huber ROTAMAT Screw Press RoS 3.2 dewatering unit with Flocculation Reactor.
The results of these tests will enable vendors to be eligible to bid for supply of polymer suitable for the
Huber Screw Press for one (1) year with the option of two (2) additional years upon mutual agreement
of the City of Bozeman and the selected vendor.
Initial Manufacturer Qualification
Manufacturers interested in participating in the Polymer Trials must submit, at a minimum, the
following items in a Notification of Interest:
1. The manufacturer must be able to provide a minimum of twelve (12) totes (~270 gal, ~2,300 lbs)
of the selected polymer to be delivered within 30 days of date of order. Upon request, supplier
must include freeze protection for shipping during colder time periods to ensure polymer
quality.
2. The manufacturer must provide current listing of ISO certifications such as 9001 and 14001 and
other relative certifications such as designation from the American Chemistry Council as a
Responsible Care® industry to demonstrate its dedication to quality control and environmental
stewardship.
3. The performance testing shall be conducted under the direction of a designated Technical
Representative (TR) provided by the manufacturer at no cost to the City of Bozeman.
Manufacturer shall list the name, address and contact information for the designated TR. Upon
award of contract, the designated TR must be responsible to quickly address the needs of the
Polymer Supplier Selection 3
City of Bozeman regarding polymer supply and quality, and provide polymer use technical
assistance.
4. Manufacturers shall include a list of a minimum of three (3) municipal wastewater customers,
with current contact information, that are currently using or have used the proposed polymer
product(s) within the last three (3) years. This information will be provided to the City of
Bozeman and its representative using the form provided in Exhibit 1.
5. Qualified manufacturers while on plant sites with polymers shall maintain product information
for all polymers that will be considered for the full-scale tests. At a minimum, product
information shall include polymer name, product number, current material safety data sheet
(MSDS) and product specification indicating the % active polymer content.
Notification of Interest package must be received by the City of Bozeman, Montana by the following
representative:
Tom Radcliffe
City of Bozeman Water Reclamation Facility (WRF)
2245 Springhill Rd., Bozeman, MT 59718
Phone: (406) 582-2928
Email: tradcliffe@bozeman.net
Based on results of the review of the information provided with the Notification of Interest,
manufacturers that meet the qualifying criteria will be selected to participate in the polymer equipment
and polymer trials program as outlined in the schedule in the Polymer Testing Protocol section.
Polymer Specifications
The polymer equipment and polymer to be tested and bid shall be suitable as a conditioner for screw
press dewatering of anaerobically digested (mixed) primary and secondary sludge biosolids from the
Bozeman WRF. Polymers to be tested shall be high molecular weight cationic or anionic emulsion type
(cationic expected) compatible with the City’s existing polymer mixing and feed equipment noted above.
The polymer may be used for thickening of waste activated sludge via a rotary screen thickener.
Polymer must maintain at least ninety percent (90%) effective strength for a minimum of six (6) months
after delivery when stored in a covered, heated, and ventilated area (60°F to 80°F).
Polymer Testing Protocol
The prequalification polymer testing consists of (i) bench-scale jar testing and (ii) full-scale performance
testing. To prepare for the polymer testing, site visits by manufacturers to the WRF facilities are by
appointment only coordinated through the key facility representative. Key operator contacts will be
provided upon selection to participate. Unauthorized/unscheduled facility visits at any time by the
manufacturer or its representatives are grounds for removal from the polymer trials program.
Polymer Supplier Selection 4
• Bench-scale Testing
Manufacturers will bench-scale test their polymer product(s) to determine which product
provides the best potential thickening. Bench-scale testing will be conducted by appointment
only by the manufacturers TR. All testing will take place at the Water Reclamation Facility (WRF)
Laboratory located at 2245 Springhill Rd., Bozeman, MT. Representative samples of
anaerobically digested sludge for dewatering testing will be provided and delivered by the WRF
operations staff. All manufacturers who are selected to participate will be given an appointment
to perform tests to screen their polymers. The appointment will be arranged at a date/time
mutually agreeable upon with the WRF staff and the TRs. TRs may begin jar or other tests at
8:00 AM and shall complete all work by 3:00 PM, on the same day. Manufactures and TRs are
responsible for any lab and testing equipment they feel necessary to conduct their tests beyond
or in addition to the supplies and equipment available for use at the WRF.
• Full-scale Performance Testing
Full-scale testing will be performed by WRF operations staff with technical input from the TRs. A
meeting will be held individually with each manufacturer before initiation of the full-scale
testing to review the goals, conditions, testing protocol and responsibilities for the testing. The
full-scale testing program will be conducted at WRF Solids & Dewatering Building and
Laboratory, scheduled from July 26, 2021 – August 20, 2021. A detailed full-scale testing
schedule will be developed to coordinate plant operations, TR availability, polymer supply, etc.
Prior to and during testing, the polymer supplier shall ensure that equipment to be used in the
test at the plant will not adversely affect test results. The TR is responsible for verifying that test
conditions and equipment are acceptable.
All pumps, tanks, mixers, etc. required for full-scale testing, in addition to what is available with
WRF’s existing blending and feed equipment, shall be provided and set up by the polymer
supplier. Each TR will be responsible for performing any preliminary tests needed to determine
initial polymer dosage required to minimize the effect on subsequent operations and to insure
than an adequate supply of polymer is provided for the duration of testing. Polymer supply for
up to 24 hours (two 8 to 10 hr days) will be allowed for each polymer proposed. The specific test
duration (within the limits outlined above) and polymer quantities will be determined by the
polymer supplier. The polymer for performance testing must be delivered to the respective
facility at no cost to the City of Bozeman. Polymer shall be delivered to the plant a minimum of
24-hours prior to the scheduled testing date.
A daily trial schedule will be established prior to the testing date. On the day of the testing, each
TR will be given an ample amount of time to make adjustments regarding polymer makeup and
feed conditions (polymer mix conc., initial feed rates, etc.) before the official trial period begins.
TRs will be allowed to sample the feed sludge at a single representative point of the process as
designated by the Treatment Plant Superintendent or Operations Supervisor.
Polymer Supplier Selection 5
The following conditions will apply to the full-scale performance test:
1. Full-scale testing will be allowed by appointment only.
2. A meeting will be held individually with each manufacturer before initiation of full-scale testing
to review the goals, conditions, testing protocol and responsibilities for the testing.
3. A maximum of two (2) people from the polymer manufacturer will be allowed on-site during the
test.
4. A minimum of eight (8) hours, and a maximum of (10) hours per day of testing. Under no
circumstances shall tests be continued past 5:00 PM.
5. Dosing will be tested at 26 GPM screw press feed flow (2019-2020 AVG) and 33 GPM (2019-
2020 MAX). For 26 GPM, a minimum of three (3) polymer doses will be required. For 33 GPM, a
single (1) polymer dose meeting the performance criteria will be required.
6. Required doses will be run as close as possible to:
a. 26 GPM: Lowest possible dosage (lbs AP/dry ton) to achieve performance goals, second
dose at 2-4 (lbs AP/dry ton) increase, and a final dose at 4-6 (lbs AP/dry ton) increase.
b. 33 GPM: Lowest possible dosage (lbs AP/dry ton) to achieve performance goals.
c. Each of the defined doses will be run twice for a combined minimum of eight (8)
samples. Operating parameters may be changed while testing the same polymer dose as
described in Condition 8. Any remaining time can be used to retest doses or expand
dose testing to increase efficiency.
7. Average of the three (3) best acceptable samples at 26 GPM will be used for evaluation. Each
dose range must have a sample meet the performance criteria. Failure to meet the performance
criteria at 33 GPM will be taken into consideration and may result in disqualification.
8. Operating parameters including polymer carrier/mixing water, screw press floc tank feed mixing
valve, screw press floc tank mixing speed and screw press speed are available for adjustment at
the TRs request.
9. Plant personnel will collect and composite samples. Samples will be collected prior to wash cycle
initiation for timing purposes and consistency among manufacturers.
a. Samples collected and analyzed will include screw press cake solids and screw press
supernatant (screwnate) via moisture balance and total solids (TS) respectively.
b. The first sample shall be collected ~60 minutes after dewatering device startup.
c. Thereafter, samples shall be collected every ~60 minutes.
d. Changes to polymer dose and/or other parameters are to be adjusted following sample
collection and ran continuously for ~60 minutes.
10. Plant personnel will analyze samples. Split samples may be analyzed by a state of Montana
certified laboratory, at the manufacturer’s request and expense.
Polymer Supplier Selection 6
11. The manufacturer, at their own expense, shall remove and lawfully dispose of all unused
product and containers at the conclusion of testing. At the City’s request, the manufacturer shall
turn over any remaining unused blended polymer to the City at no cost.
In the event of equipment breakdown or malfunction, the City of Bozeman may elect (at their
discretion) to reschedule a full-scale performance test. In this event, rescheduled date(s) shall be
mutually agreed upon by the City of Bozeman and the manufacturer(s).
The City of Bozeman reserves the right to terminate testing immediately at their discretion if they
determine that a polymer product does not meet the performance requirements or that the polymer
being utilized is detrimental to equipment operation or performance.
The manufacturer shall monitor the testing to verify that all polymers and other related variables are
within normal operating parameters. The TR should communicate any concerns to the Treatment Plant
Superintendent or individual designated by the manager to supervise the test no later than two (2) days
after completion of testing. TRs cannot directly request operators to make process changes other than
indicated herein. Polymers that require the equipment to be run outside normal operating variables will
be removed from consideration.
Upon completion of the full-scale trials, a copy of the performance data for the particular polymer
supplied by and tested for a manufacturer will be supplied to that manufacturer’s TR for use in
developing bid documents.
Expected Dewatering Performance: (minimum criteria)
Parameter Value Units
Dry Tons per Year 1,460 Bone Dry Standard Ton/Year
Tons per Day 4.0 (output) Bone Dry Standard Ton/Day
Gallons per Day 37,000-48,000 (at 2.5% TS inlet) GPD
Feed Gallons per Minute 26 & 33 (at 2.5% TS inlet) GPM
Average Inlet Consistency Percent
Total Solids 1.5-3% % TS
Minimum Outlet Consistency
Percent Total Solids 17% % TS
Operating Days per Year 365 Days
Operating Days per Week 7 Days
Operating Hours per Day 24 Hours
Polymer Supplier Selection 7
Polymer Performance Evaluation Criteria
The following equations provide evaluation criteria that will be used during the trials and with full-
scale performance test data and submitted bids to identify the most cost effective product:
Polymer Feed Rate, PFR, (GPH)
*Pump setting for each sample will be plotted on pre-test pump calibration graph/trend.
Screw Press Loading, SL, (dry ton/hr)
SL = (SFR × 60 min/hr × DTS × 8.34 lbs/gal) / 2000 (ton/lbs)
Where:
SFR = Screw Press Feed Rate (GPM) *Trial testing operating setpoint
DTS = DIG #3 (Digester #3) Total Solids (%) *Sample tested in lab
Pounds Active Polymer, PL, (lbs AP/dry ton)
PL = (PFR × PD × PA) / SL
Where:
PFR = Polymer Feed Rate (GPH) *Pump calibration
PD = Polymer Density (lbs/gal) *Manufacturer data
PA = Active Polymer (%) *Manufacturer data
SL = Screw Press Loading (dry ton/hr) *Trial testing data
Solids Recovery, R (%)
R = [CTS × (DTS-STS)]/[DTS × (CTS-STS)] × 100
Where:
CTS = Screw Press Cake Total Solids (%) *Trial sample tested in lab
DTS = DIG #3 Total Solids (%) *Trial sample tested in lab
STS = Screwnate Total Solids (%) *Trial sample tested in lab
Polymer Cost, PC, ($/dry ton)
PC = (PFR × P$) / SL
Where:
PFR = Polymer Feed Rate (GPH) *Pump calibration
P$ = Polymer Cost ($/gal) *Manufacturer data
SL = Screw Press Loading (dry ton/hr) *Trial testing data
Polymer Supplier Selection 8
Polymer Cost, PCR, ($/dry ton) *Recovery Factored
PCR = PC / R
Where:
PC = Polymer Cost ($/dry ton) *Trial testing data
R = Solids Recovery (%) *Trial testing data
Polymer Cost, PCD, ($/day) *Recovery Factored (Estimate polymer cost/day assuming 4 dry ton)
PCD = PCR × 4 dry ton/day
Where:
PCR = Polymer Cost ($/dry ton) *Trial testing data
Polymer Supplier Selection 9
Example Polymer Performance Calculation per Qualified Polymer
P$ = Polymer Cost ($/gal) $8.50/gal *Manufacturer data
PD = Polymer Density (lbs/gal) 8.50 lbs/gal *Manufacturer data
PA = Active Polymer (%) 40% *Manufacturer data
SFR = Screw Press Feed Rate (GPM) 26 GPM *Trial testing operating setpoint
DTS = DIG #3 Total Solids (%) 2.50 % *Sample tested in lab
CTS = Screw Press Cake Total Solids (%) 18.00% *Trial sample tested in lab
STS = Screwnate Total Solids (%) 0.30% *Trial sample tested in lab
PFR = Polymer Feed Rate (GPH) 1.50 GPH *Pump calibration
Screw Press Loading, SL, (dry ton/hr)
SL = (SFR × 60 min/hr × DTS × 8.34 lbs/gal) / 2000 (ton/lbs)
SL = (26 GPM × 60 min/hr × 2.50 % × 8.34 lbs/gal) / 2000 (ton/lbs) = 0.163 dry tons/hr
Pounds Active Polymer, PL, (lbs AP/dry ton)
PL = (PFR × PD × PA) / SL
PL = (1.50 GPH × 8.50 lbs/gal × 40%) / 0.163 dry tons/hr = 31 lbs AP/dry ton
Solids Recovery, R (%)
R = [CTS × (DTS-STS)]/[DTS × (CTS-STS)] × 100
R = [18.00% × (2.50 % - 0.30%)]/[ 2.50 % × (18.00% - 0.30%)] × 100 = 89%
Polymer Cost, PC, ($/dry ton)
PC = (PFR × P$) / SL
PC = (1.50 GPH × $8.50/gal) / 0.163 dry tons/hr = $78.40/dry ton
Polymer Cost, PCR, ($/dry ton) *Recovery Factored
PCR = PC / R
PCR = $78.40/dry ton / 89% = $87.60/dry ton
Polymer Cost, PCD, ($/day) *Recovery Factored (Estimate polymer cost/day assuming 4 dry ton)
PCD = PCR × 4 dry ton/day
PCD = $87.60/dry ton × 4 dry ton/day = $350.42/day
Polymer Supplier Selection 10
Exhibit 1
References
(Must be completed by manufacturer and included with Notification of Interest)
City of Bozeman
Water Reclamation Facility (WRF)
2021 – Polymer Trials
Vendors shall provide references on this form. References must be of organizations having similar
facilities as City of Bozeman Water Reclamation Facility (WRF).
Manufacturer:
1. Name or Utility:
a. Contact:
b. Title:
c. Mailing Address:
d. Phone:
e. Email:
2. Name or Utility:
a. Contact:
b. Title:
c. Mailing Address:
d. Phone:
e. Email:
3. Name or Utility:
a. Contact:
b. Title:
c. Mailing Address:
d. Phone:
e. Email: