Optimization of the Sludge Dewatering System - PowerPoint PPT Presentation

1 / 28
About This Presentation
Title:

Optimization of the Sludge Dewatering System

Description:

Due to the significant industrial loading for this plant during ... Collection Trays. Belt Conveyor. Proposed Plan View of the New Pressure Filtration System ... – PowerPoint PPT presentation

Number of Views:279
Avg rating:3.0/5.0
Slides: 29
Provided by: unkn1180
Category:

less

Transcript and Presenter's Notes

Title: Optimization of the Sludge Dewatering System


1
Optimization of the Sludge Dewatering System
  • Present by Rui Zhang
  • Civil Engineering Department
  • Client Niagara Falls Wastewater Treatment Plant

2
Contents
  • Client and Site Background
  • Overview of Project Approach
  • Parameters Used for the Analysis
  • Economic Modeling
  • Test Results
  • Conclusions and Recommendations

3
Client the City of Niagara Falls Wastewater
Treatment Plant
  • Home Niagara Falls, New York
  • Birthday 1977
  • Service Population 61,840
  • Flow Design-48mgd, peak-85mgd, current-35mgd
  • Due to the significant industrial loading for
    this plant during 1960s and 1970s,
    physical-chemical treatment was chosen instead of
    biological treatment.
  • In 1994, EPA referred to it as the most
    successful operation of any of the municipal
    carbon treatment facilities in the country.

4
Site Background
5
Existing Sludge Management System
6
Proposed Sludge Management System
7
Project Objective
  • Feasibility study
  • Find the scenarios where the alternative is an
    economically preferred option
  • Determine the payback
  • Evaluate the space requirements
  • Develop a schematic design

8
Overview of Project Approach
  • Review the pilot test data
  • Examine the existing plant equipment, structure
    and procedures
  • Select equipment and size the equipment within
    the existing system
  • Develop economic modeling to do feasibility study
  • Calculate payback period and give recommendations

9
Parameters Used for the Analysis
  • Solid Content Based on Pilot Test Data
  • Disposal Cost Production Rate
  • Current Dewatering Performance and Financial
    Parameters and Assumptions

10
Pilot Test Data from 1994
11
Disposal Cost Production Rate
12
Current Dewatering Performance and Financial
Parameters and Assumptions
13
Economic Analysis Factor
  • Debt Service 20-year period
  • Interest Rate 6 as the city controller
    recommended, range 0-12
  • Capital Recovery Factor, range 0-15
  • Disposal Cost and Production Rate
  • Actual Capacity of the Pressure filtration System
    (percent of post-lime sludge treated by the new
    system per year, range
  • 0-100

14
Equipment Selection
  • One Mini-Miser DC450 sludge processing system
    from RECRA Inc. was chosen as the secondary
    dewatering system due to the available pilot test
    data, low OM cost, compact design, automated,
    compatibility with the existing facilities and
    acceptable capital cost.
  • The dimensions height-7.23ft, width-9.84ft,
    length-26.3ft (available space 41ft by 45ft)
  • The unit cost 450,000
  • OM cost 30,000/year

15
Mini-Miser Dewatering System
  • Automated Feeding System
  • Pressbags
  • Grooved Racks
  • Hydraulic Cylinders
  • Collection Trays
  • Belt Conveyor

16
Proposed Plan View of the New Pressure Filtration
System
17
Proposed Position of New Inclined Conveyor and
Pressure Filtration System
18
Estimated Project Capital Cost
  • Equipment cost
    450,000
  • General construction
  • Install press hopper
    1, 200
  • Concrete steel support 1,
    000
  • Conveyor system
    1, 200
  • Electrical
    45, 000
  • Miscellaneous construction cost 2, 000
  • Subtotal
    504, 000
  • Contingency (10)
    56, 000
  • Estimated Project Capital cost
    560, 000

19
Economic Modeling by Using MPL Modeling System
  • Objective Function
  • Minimize AA1-A2
  • Subject to
  • 0lt CRFlt 15 0lt X1lt
    100
  • X1 X2 1 DCgt 0 PRgt
    0 A0
  •  
  • Where
  • A1 is the annualized cost of the new dewatering
    system. (BFPPFS)
  • A2 is the annualized cost of the current
    dewatering system. (BFP)

20
Summary of Variable Definition
21
Summary of Macro Definition and Formula
22
Sensitivity Analysis
  • It was used to determine what effect each
    variable will have on the objective function when
    the variable increases by one unit.
  • In many applications, the values of a models
    parameters may change. If this occurs,
    sensitivity analysis often makes it unnecessary
    to solve the problem again in order to obtain the
    new optimal value to the objective function. This
    is of great use, especially when the linear
    program is very large and resolving it can take a
    long time.

23
Test Results
24
Payback Period
  • Annual Disposal Cost Savings (13.8/0.351) wet
    ton/day 29.826.25/wet ton 5day/week52weeks/y
    ear 80,000/year
  • Subtract the OM cost (30,000), the net Disposal
    Cost Savings is 50,000
  • Payback Project Capital Cost / net Annual
    Disposal Cost Savings 560,000/50,000 11 years
  • Based on the maximum 6 years payback expectation
    without subsidy on this project, the disposal
    cost would have to be at least 40/wet ton. (Or a
    production rate would be at least 21dry ton/day).

25
Limitations
  • More recent pilot scale testing should be used
    for more accuracy.
  • More alternatives should be checked for
    additional dewatering.
  • The analysis is based on a conceptual design and
    a full-scale design is needed for accurate cost
    estimation.

26
Conclusion
  • Available space is adequate for the new
    equipment, a Mini-Miser DC450.
  • It is cost-effective in the long term for the
    City of Niagara Falls to add pressure filtration
    to the dewatering system. The annualized
    dewatering cost savings from this upgrading
    project is 1, 140 for 2000 year.
  • The calculated payback in 2000 year is 11 years.
    To get a payback of 6 years, the disposal cost
    would be 40/wet ton at least or the production
    rate would be 21 dry ton/day with all other
    parameters hold.

27
Recommendations
  • The city of Niagara Falls WWTP pursue the
    upgrading sludge dewatering project as long as
    more favorable scenarios can be expected
  • The economic model is strongly recommended for
    use in feasibility studies of potential
    technologies.
  • A pilot scale secondary dewatering project should
    be implemented such that the project costs and
    potential revenues can be more accurately
    established.
  • EPA innovative or alternative status should be
    checked for more favorable technologies in
    future.
  • Make application for Clean Water State Revolving
    Fund. One-third to one-half of the market
    interest rate can be saved for qualified project.

28
Questions?
  • Thanks very much for your time
Write a Comment
User Comments (0)
About PowerShow.com