Post on 01-Aug-2020
transcript
April 2016
Are You Getting Your Money’s Worth?
Dividends of Performance-Based Polymer ProcurementKeller Schnier, PE
Asheville, NC
Acknowledgements
Maggie Macomber, PE – Charlotte WaterJackie Jarrell, PE – Charlotte WaterDavid Wagoner, PE – CDM Smith
Presentation Take Aways
Key steps in the polymer selection program Importance of:
• Proper polymer selection• Planning the process• Qualified participation• Maintaining control of the process
Polymer selection determination• Lowest cost polymer = best value?• Relationship between performance and overall cost
3
Importance of Proper Polymer Selection
Cost Control• Equipment• Operations• Polymer - type• Biosolids - end use/disposal
Quantity • Dewatering performance
Quality • Handling• Odors
4
Polymer Selection Goal
Produce the best biosolids product for the lowest cost• Best product fits your program needs• Lowest Cost
‒ Polymer cost (selection and usage based)‒ Operations and maintenance cost (operator and equipment)‒ Reuse/disposal cost (performance based)
5
Polymer Selection – Step-Wise Approach
Step 1 – Consider 3rd Party Project/Program manager Step 2 – Develop Customized Approach
• Baseline criteria development and desired results• Establish ground rules and polymer selection criteria• Testing plan and schedule• Vendor Solicitation/selection
Step 3 - Conduct Testing• Selected vendors• Bench-scale testing• Full-scale testing• Performance data development/handling
Step 4 - Bid document/Polymer Selection
6
Step 1: 3rd Party Project Manager
Administers Polymer Trial program Time – coordination - responsiveness Manage the process and the vendors Single point of contact Multiple plants create challenges
• Uniformity and consistency
Control of all data
7
Step 2: Customized Approach
Baseline criteria development• Historical performance• Equipment capacities
Establish ground rules and polymer selection criteria
Detailed testing plan and schedule
Vendor selection • Advertise details • Request submission of Notification of Interest• Pre-submission meeting• Selection of vendors for Trials
8
Establishing Baseline Criteria
Goal - Set boundaries/criteria for equipment operation, polymer use and required performance
System review - conditions and limitations• Polymer mixing• Feed concentrations• Feed capacity/ranges
Dewatering system performance and information• Capacity of dewatering equipment• Historic performance data• Special concerns
‒ Odors‒ Fecal coliform reactivation or regrowth
9
Plant Information and Data Summary Sheets
10
Facility Name
Type of Device
Make/Model - Attach Specification
Number of units operational
Dewatering Feed, gpm
Current Daily average flow rate per unit 320
Operating Range Min/Max per unit 250 / 390
Dewatering Feed Solids, % solids
Average 2.7
Minimum 2.3
Maximum 3.3
Dewatered Solids, % Solids
Desired 22
Historical 18.5
Lower Limit 18
Filtrate/ Centrate/Supernatant Solids, mg/L TSS
Desired 100
Historical 150
Upper Limit 500
Operating schedule
days of the week 5
hours/day 24
Number of units normally operated 1
Polymer storage/mix/feed
NSF Standard 60 Certification required No
Dedicated to thickening or combined with dewatering Combined
Polymer delivery - drum, tote, bulk Bulk
Polymer mixing system type - batch, continuous Batch, DW/TK Combo
Batch tank mixer type
Mix tank volume & batches per day4500 g X 3/13 M-F &
1.5 S-S
Make-up water source; plant or potable Potable
Polymer feed system type Prog. Cavity Pump
Feed capacity range, gpm 10-35 gpm
Maximum polymer feed concentration 1.00%
Active polymer content, % 41
Neat Polymer Usage per day / year (gal) 310 / 80,600
Neat Polymer per batch (gal)
Current Polymer mix feed conc, % 0.70%
Polymer feed rate, gpm
Current Average 30
Design Min/Max 0 / 35
Maximum Polymer dosage to achieve cake solids and centrate/filtrate/supernatant specified, lb total polymer/dry ton solids 60
Cake Solids
Filtrate/Centrate Solids
Max. Polymer Dosage
11
SUBJECT: SOLICITATION OF INTEREST FOR POLYMER SUPPLY CONTRACT To Whom It May Concern: The ________is currently contacting polymer manufacturers that may be interested in supplying polymer for a twelve (12) month period. The polymer will be used in the sludge thickening and dewatering processes at the following facilities ______. Prequalification testing of polymer products will begin in _______. Interested Manufacturers are required to provide a Notification of Interest to:
Notifications will be accepted until ___________. All information listed in the Applicant Qualification must be submitted in the Notification. Incomplete or partial submittal of information will not be accepted. A prequalification testing protocol, containing manufacturer qualifications, existing feed equipment description, polymer type specification, sludge characteristics, and evaluation criteria, is attached to this letter for reference. Please read the prequalification testing protocols very carefully. The polymer supplied shall be suitable as a conditioner for:
• anaerobically digested sludge prior to centrifuge or belt filter press dewatering, • water treatment plant alum sludge prior to gravity thickening followed by belt filter press
dewatering and • secondary sludge centrifuge and gravity belt thickening prior to anaerobic digestion.
The polymer supplied by the manufacturer shall be an anionic or cationic emulsion type. No gel, dry or liquid polymers will be accepted. The polymer shall be compatible with the City's existing equipment and treatment scheme and cause no impacts to effluent quality. The prequalification testing process includes: Bench-scale Laboratory Jar Testing: All manufacturers who express an interest will be given an appointment between ______________ to perform jar tests to screen their polymers. Each manufacturer may prequalify more than one product, but only one polymer will be chosen for full scale testing. Designated plant staff (or the city's representative) will be available to assist with jar testing in accordance with the polymer testing protocol. Full-scale Performance Testing: Manufacturers submitting products for full-scale testing will be given eight (8) to ten (10) hour appointments to demonstrate performance. Full-scale testing will be conducted during the months of ________________________. Manufacturers shall provide sufficient quantity of polymer to perform the full-scale tests using plant polymer feed systems on the designated thickening and/or dewatering equipment at no cost to the City. Minimum acceptable performance conditions are provided in the attached information. Manufacturers whose polymers have proven to be effective and acceptable based on achieving the minimum acceptable performance requirements during the full-scale performance tests will be invited to offer a sealed bid.
Prequalification
Minimum acceptable performance conditions
Bench-Scale & Full-Scale
Testing
Control the Number of VendorsSeek Strong Technical Experience
12
Manufacturer
ISO 9001
MSDS
Service ResponseReferences
Sufficient Capacity
Other Key Items in the Solicitation
Full-Scale testing and sampling details• Procedural approaches• Performance data development
Polymer Performance Evaluation Calculations• Calculations to be used
Full transparency • Avoid questions/contested
conditions later
13
Full-Scale Test and Sampling Details
14
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, 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 ten (10) hours per day of testing. Under no circumstances shall tests be continued past 5:30 P.M.
5. Minimum of five (5) acceptable polymer dosages with at least 30 minutes of run time per dosage.
6. Maximum of eight (8) acceptable polymer dosages with at least 30 minutes of run time per dosage.
7. Five (5) defined doses (minimum requirements) to be run as close as possible to:
a. Lowest possible dosage (lbs/dry ton) to achieve performance goals, the next higher integer dosage (lbs/dry ton), and three (3) more dosages in 2 to 5 lbs/dry ton increments (total of 5 dosages);
b. Each of the defined doses will be run twice for a maximum of ten (10) sample sets, and a maximum of sixteen (16) sample sets.
8. Average of the five (5) best acceptable sample sets will be used for evaluation
9. Plant personnel will collect and composite samples for the 30 min run period for each dosage.
a. The first sample shall be collected 10 minutes after thickening/dewatering device startup;
b. Thereafter samples shall be collected every 10 minutes (3 samples in 30 minutes).
10. Plant personnel will analyze samples and split samples will be analyzed by CMUs state certified laboratory.
Polymer Performance Evaluation Criteria
15
Solids Feed Rate, SF, (lb/d)
SF = 8.34 x QF x CF
Where: QF = sludge feed rate (gpm) CF = sludge feed concentration (mg/L)
Polymer Feed Rate, SP, (lb/d)
Sp = 8.34 x QP x CP Where:
QP = polymer feed rate (gpm) CP = polymer feed concentration (mg/L)
Polymer Feed Concentration (Neat), CP, (mg/L) CP = 120,090 x M / (VP+ VW)
Where:
M =Mass of neat polymer per test batch (lbs) VP =Volume of polymer per test batch (gallon) VW = Volume of water per test batch (gallon)
Polymer Usage, PU, (lb polymer/dry ton) PU = SP / (SF/2,000)
Solids Recovery, R (%)
R =100 x C x (F-B)/(F x (C-B)) Where: C =Total cake solids (%) F =Sludge feed solids (%) B =Centrate solids (%)
Example Polymer Performance Calculation
16
Biosolids Production (avg): 10 dry ton/day (from polymer trials) Land Application Costs: $15/wet ton (current contract rate) Polymer Dose (avg): 20 lb/dry ton (from polymer trials) Polymer cost: $1.00/lb (from polymer bid) Dewatered Cake Solids (avg): 20% solids (from polymer trials) % recovery (avg): 98% (from polymer trials) Polymer cost per day = 5 dt/d x 20 lb/dt x $1.00/lb / 0.98 recovery = $102.04/day Land Application Costs = 5 dt/d x $15/wt / 0.20 % solids = $375/day Total Cost = $102.04 + $375 = $477.04/day
Selection of Qualified Vendors
Pre-submittal meeting with interested Vendors Receive and review Letters of Interest Select 3 to 4 most qualified vendors
17
Step 3: Conduct Testing
Facility tours with Vendors • Equipment review• Polymer measurement, mixing, and feed rate/control arrangements• Q&A
Refine Testing Schedule Bench-Scale Testing Full-Scale Testing
18
Bench-Scale Testing
Conducted at plant site - lab setting• Vendor conducts, Owner/PM observes • One vendor at a time
Sludge samples provided by Owner Owner keeps samples of polymers being considered for full-
scale trials Vendor chooses polymer to advance to full-scale trial
• Projects and presents dosage rates for full-scale testing‒ lb polymer/dry ton of solids‒ Must fall within acceptable dosage range criteria
19
Full-Scale Testing
Set dewatering machine operating conditions• Based on equipment operation ranges ~ mid range• Test all polymers under same conditions – level playing field
Sample collection, control and testing – by Owner• Microwave % solids analyzing unit
Data management by Project Manager Performance criteria – pass/fail and range
limitations• Maximum allowed polymer dosage • Minimum solids capture % or max TSS levels• Minimum/maximum cake solids
Performance data finalization
20
Step 4: Vender Bid Price Submittal and Polymer Selection Facility: WWTP Address: ITB 269-0131-010
Manufacturer Product Price Per Pound A NC 101 $ 0.96 B K290FLX $ 1.185 C 8846FS $ 1.11 D SE 757 $ 0.84
21
Vendor A
22
$0.96
$127.46
Vendor D
23
$0.84
$128.57
Performance Conditions + Polymer Price = Lowest Cost Outcome
24
Based on performance conditions, Vendor D could have won the contract with a bid of $0.81/lb or lower
Performance data provides documentation of the expected performance….once selected polymer is used
Summary
All polymer is not created equal• Purchasing polymer based on $/lb polymer alone risky
Polymer Trials can:• Provide competitive, performance based polymer selection• Qualify polymer vendors with technical expertise • Set clear instructions and guidelines• Control the process
‒ Trials protocol, sampling, testing, selection criteria• Develop performance data for each polymer
‒ Consistent testing conditions for all• Apply bid price to performance conditions for lowest cost outcome
25
Questions
schnierkw@cdmsmith.com
Are You Getting Your Money’s Worth?AcknowledgementsPresentation Take AwaysImportance of Proper Polymer SelectionPolymer Selection GoalPolymer Selection – Step-Wise ApproachStep 1: 3rd Party Project ManagerStep 2: Customized ApproachEstablishing Baseline CriteriaPlant Information and Data Summary SheetsSlide Number 11Control the Number of Vendors�Seek Strong Technical ExperienceOther Key Items in the SolicitationFull-Scale Test and Sampling DetailsPolymer Performance Evaluation CriteriaExample Polymer Performance CalculationSelection of Qualified VendorsStep 3: Conduct TestingBench-Scale TestingFull-Scale TestingStep 4: Vender Bid Price Submittal and Polymer SelectionVendor AVendor DPerformance Conditions + Polymer Price = Lowest Cost OutcomeSummaryQuestions