This document describes the wastewater treatment process for a milk manufacturing plant using a membrane bioreactor (MBR). The major processes in milk manufacturing that generate wastewater are dumping, compounding, processing, milk storing, evaporation and drying. The MBR wastewater treatment plant employs drum screens, equalization tanks, DAF, aeration tanks, MBR tanks, and centrifuges. Key stages include neutralization, coagulation/flocculation, biological treatment via aeration, solid/liquid separation using membranes, and dewatering of sludge using centrifuges. The MBR system achieves high quality effluent by effectively treating compounds that conventional activated sludge plants cannot degrade.

1. Membrane Bioreactor (MBR)
Wastewater Treatment Plant
In
Milk Manufacturing
WAST CY402 – Industrial
Wastewater Treatment
Process
Jojo Taguinod
Sumant Patel
By:

2. DUMPING
COMPOUNDING
PROCESSING
MILK STORING
EVAPORATION
DRYING
MILK MANUFACTURING MAJOR
PROCESSES

3. COMPOUNDING:

4. EVAPORATION:

5. Drying
Conventional Waste Sources:
• Unused Rework powder
• Caustic/Acid waste from CIP
• High strength wastewater BOD/COD/Nutrients rich
wastewater from raw materials
• Oil and grease
• Cleaning agents (sterbac, divosan, divoquat, etc.)
Google image

6. Piping & Instrumentation Diagram
Drum screen
Equalization Tank
DAF
Aeration Tank
MBR
Permeate Tank
Centrifuge
Chiller Heat Exchanger

7. Drum Screen
Domestic and plant wastewater enters the rotating drum
screen which filters any incoming trash or serve as grit
removal. Drum screened wastewater enters the influent
pump station which contains pumps to transfers the
wastewater to the equalization tank.
Google image

8. Equalization Tank
Wastewater is neutralized and equalized in the equalization tank.
Sulfuric acid and caustic soda are used to neutralize the pH. Antifoam
is also used.
AIR STRIPPING:
Recirculation pumps together with the equalization blowers are used to
efficiently mix and aerate the contents of the equalization tank and keep
it aerobic. Anaerobic would produce H2S and gaseous ammonia.
Google image

9. Coagulation/Flocculation/ Dissolve Air
Floatation
Chemical treatment via coagulation and
flocculation combined with
dissolved air flotation reduces the
COD of the wastewater by roughly 30 to 40%. The DAF
float/sludge is transferred to the DAF sludge tank which is
further transported via the DAF sludge/solids pumps to the
sludge holding tank. Treated DAF effluent is fed to aeration
tanks. The DAF serves as a pre-treatment to the MBR.
Chemicals needed: Pacl, polymer
Air is the driving force
Google image

10. Coagulation/Flocculation/ Dissolve
Air Floatation

11. Coagulation/Flocculation/
Dissolve Air Floatation
Before
adding
chemicals
After adding
chemicals
After injecting air

12. Bioreactor/Aeration Tank
Biological treatment is employed to further treat the
wastewater using microorganisms. Chemicals needed
include: phosphoric acid, antifoam, caustic

13. Bioreactor/Aeration Tank

14. Membrane Bioreactor
The MBR system comes with a cooling package. The chillers together
with the heat exchanger regulate the temperature of the bioreactor
mixed liquor before feeding to the membrane tanks. Needs antifoam.

15. Membrane Bioreactor
Hollow fiber membranes which filter the wastewater coming from
the bioreactors.

16. Membrane Bioreactor
During permeation During backwash
To permeate
tank
From permeate
tank

17. Sludge Holding Tank
The sludge holding receives sludge from WAS (waste
activated sludge) from the MBR and sludge from the DAF
(dissolved air flotation) floatation and feeds to the
decanting centrifuge. SHT needs polymer and antifoam.

18. Decanting Centrifuge
The centrifuge dewaters DAF float and waste activated
sludge from the MBR. It uses centrifugal force to separate
the solids efficiently. Needs polymer.

19. Decanting Centrifuge
After adding
chemicals
Before adding
chemicals
After centrifuge

20. Membrane BioReactor
Key Performance
Indicator:

21. Issues with Conventional
Activated Sludge WWTP
• Ineffective in degrading sucralose, research by Cesar Torres and Rosa
Krajmalnik-Brown at the Arizona State University’s Biodesign Institute
• Micro plastics from portions of polyester, acrylic and other Synthetic
polymers had contaminated 18 shores across six continents, research
by Mark Anthony Browne of the University College Dublin Ireland,
School of Biology and Environmental Science
• In 2010, the government of Canada proposed for new stricter rules to
regulate the effluents of wastewater treatment plants
Deleterious Substance National standard
Ave carbonaceous BOD ≤ 25 mg/L*
Ave total residual chlorine concentration ≤ 0.02 mg/L*
Maximum conc. of un-ionized NH3 < 1.25 mg/L#
Ave concentration of suspended solids ≤ 25 mg/L*

22. References:
 Dissolved air flotation. Retrieved from:
http://en.wikipedia.org/wiki/Dissolved_air_flotation
 Membrane bioreactor. Retrieved from:
http://en.wikipedia.org/wiki/Membrane_bioreactor
 Membrane Bioreactor (MBR). Retrieved from:
http://www.gewater.com/products/membrane-bioreactor-
mbr.html
 WPI – Pfizer Global Manufacturing

23. End…
Thank You!!!