Tuesday, November 18, 2008

Membrane Characterization (UF/MF)

Pore size
Molecullar weigh cut-off using dextran or polyethylene glycol (PEG) rejection. The pore size is determine as the molecular weigh of particle that can be rejected 90% by membrane. The filtration is conducted by filtering the serries of differend dextran MW solution. The rejection profile than defined by the linearization of the rejection-MW curve. Normaly the concentration of the dextran is less than 2% w/w. 

Procedure of PEG rejection test (A. D. Sabde et al. [1997]):
Reagents
  1. 5% w/v BaCl2 in 1 N HCl (100 ml)
  2. 100 ml of 2% KI (w/v)  + 1.27 g I2 --> This mixture than dilluted 10 times.

Procedure:
  1. Add 1 ml reagen 1 to 4 ml sample --->  (I)
  2. Add 1 ml reagen II to  solution I ---> (II)
  3. Allow the color development for 15 minutes at room temperature
  4. Read the absorbtion using spectrophotometer at 535 nm againt reagent blank
Note: To get the concentration value, the calibration curve is required.


Pore size distribution
Bubble  


Porosity



Surface structure


Monday, November 17, 2008

Lab Scale MBR

Planning the lab scale MBR



Figure 1. Labscale MBR


Specification:

No

Spare part (unit)

Specification, Price

Notes

1

Bioreactor tank (1)

50x25x30cm (39.93€)

2

Feed tank (1)

-

It can be any used tank in volume of 30-40 liters

3

Level control tank (1)

-

It can be any used tank in volume of 3-4 liters

4

Feed pump (1)

Circulation pump to level control tank (19.80€)

5

Air pump (1)

Maximum flow rate 550 l/h (59.29€)

6

Air diffuser (5 unit)

Bubble size 100-500 µm (1€/Pieces)

7

Air flow meter (1)

-

8

Submerged membrane module (depend on requirement)

Prepared by us

9

Vacuum pump (1)

The purchasing is in progress

10

Centrifugal pump (1)

The purchasing is in progress

11

Pressure gauge (3)

The purchasing is in progress

12

Valve (5)

(1€/Pieces)

13

Pipe line (depend on requirement)

1€ / m

14

Cross flow membrane module

Prepared by us

Price was taken by direct survey to: De Servis Leuven bvba, Diestsstraat 133 - 3000 Leuven

Instrumentation and analysis

Parameters

Price

*MLSS

-

*COD

-

*Turbidity

-

pH

58.99€

Temperature

20.6€

Dissolved oxygen (DO)

Water proof (947.43€), Not water proof (712.69€)

Oxidation-reduction potential (ORP)

136€

pH controller

373.89€

Temperature controller

160€

Flux

-

Remarks:

  • These is basic instrumentation to operate the activated sludge system or membrane bioreactor. The more instrumentation analysis are required for more detail observation.
  • The other parametersthat could be required to be tested are, NO-2 -N, NO-3 –N, total phospor (TP) and total nitrogen (TN).
  • The detail can be found and standard method for wastewates analysis.

The operating parameters is determined according to the pilot plant parameters from MBR companies.


Friday, November 14, 2008

Mith and Fact in MBR

Myth 1: Membrane pore size determines removal efficiency in submerged MBR applications.

Fact 1: Third party independent research (Gunder, et al. The Membrane Coupled Activated Sludge Process) confirms similar performance for microfiltration versus ultrafiltration membranes submerged in mixed liquor.


UF Hollow Fiber (H) vs. MF Flat Plate (P)
Coliform Data



University of Hawaii, Comparison Data


Myth 2: All membranes perform about the same in terms of flux and or permeability.

Fact 2: Membrane performance is a function of multiple parameters not just type or geometry. Some important parameters are given below, but there are several other factors to consider as well.


Myth 3: All MBR Systems are underloaded and do not operate at or near design capacity.

Fact 3: Many Enviroquip MBR Systems run at or above rated capacity during winter and spring seasons. Some plants, like Hyrum, Utah WWTP, are more than 60% utilized throughout the year.

Hyrum, UT WWTP Flow and Utilization Data

Myth 4: Specifying average daily flow (ADF) and peak daily flow (PDF) is sufficient to characterize required capacity.

Fact 4: Establishing peak instantaneous flow (PIF) and durations is as important as ADF & PDF requirements. For example, at the McFarland Creek WWTP, instantaneous flux is much higher than average flux for most of the day between May 12 and May 19.





Myth 5: All membranes should have about the same service life.

Fact 5:
Not all membranes have the same service life. Membrane life is not only a function of design and composition it is also determined by operating conditions. Some of the keys to long service life include; low TMP operation, reduced chemical exposure and equal air scouring.

Extensive Kubota membrane life data has been collected in the U.K. indicating membrane life on the order of 12.5 years. Other technologies may only last 3 to 4 years in some cases.


Myth 6: Silt Density Index (SDI) values can increase over time degrading permeate quality.

Fact 6: Recent SDI results from a 0.5 MGD installation averaged less than 2.0. The plant is now in its 9th year of operation.


Source: http://www.Enviroquip.com

Research Project (In Europe)

AMEDEUS "Accelerate Membrane Development for Urban Sewage Purification"
Specific Targeted Research Project (Priority "Global Change and Ecosystems")
Duration: 01/10/2005 - 30/09/2008
Co-ordination: B. Lesjean, Berlin Centre of Competence for Water
(boris.lesjean(at)kompetenz-wasser.de)



EUROMBRA "Membrane bioreactor technology (MBR) with an EU perspective for advanced municipal wastewater treatment strategies for the 21st century"
Specific Targeted Research Project (Priority "Global Change and Ecosystems")
Duration: 01/10/2005 - 30/09/2008
Co-ordination: T. Leiknes, Norwegian University of Science and Technology
(torove.leiknes(at)ntnu.no)

MBR-TRAIN "Process optimisation and fouling control in membrane bioreactors for wastewater and drinking water treatment"
Marie Curie Host Fellowship for Early Stage Research Training
(Structuring the European Research Area; "Marie Curie Actions")
Duration: 01/01/2006 - 31/12/2009
Co-ordination: RWTH Aachen University, Department of Chemical Engineering
Contact: R. Hochstrat
(hochstrat(at)ivt.rwth-aachen.de)

PURATREAT
"New Energy Efficient approach to the operation of Membrane Bioreactors for Decentralised Wastewater Treatment"

Specific Targeted Research or Innovation Project (International Cooperation Action)
Duration: 01/01/2006 - 31/12/2008
Co-ordination: G. Schories, Technologie-Transfer-Zentrum Bremerhaven
(gschories(at)ttz-Bremerhaven.de)

Thursday, November 13, 2008

Manufacturer

The design of the reactor (including membrane, baffle and aerator locations) and the mode of operation of the membrane also appear as key parameters in the optimisation of the system. Several immersed MBR designs are currently proposed by the leading membrane suppliers such as GE-Zenon (Canada), X-Flow (The Netherlands), Siemens-Australia (Australia), Mitsubishi and Kubota (Japan). Kubota has the largest installation base of membrane bioreactors worldwide. In each case, the process proposed is very specific. Not only the membrane material and configuration used are different, but the operating conditions, cleaning protocols and reactor designs also change from a company to another. For example, the flat sheet membrane provided by Kubota does not require backwash operation, while hollow fibre membrane type from Zenon and Memcor (USFilter) have been especially designed to hydraulically backwash the membrane on a given frequency (around every 20 min).

Membrane and plant supplier links:

Research Group


Tuesday, November 4, 2008

Industrial membrane module

1) Mitsubishi Rayon

We provide two types of submerged hollow-fiber membranes for wastewater treatment. We offer products that best meet your purposes and applications.

Features of the SteraporeSUR(TM) series
Designed for small and medium-scale wastewater treatment
(tens to thousands of m3 per day)
Widely adopted in domestic and industrial wastewater treatment
(Installed at a total of over 2,000 plants as of September 2007)
Multi-unit configuration in accordance with the depth
Uses polyethylene hollow-fiber membranes
High cost-effectiveness
Permanently hydrophilic membrane surface
Thermally recyclable
Magnified image of the surface of the polyethylene hollow-fiber membrane
STERAPORESUNTM
membrane element

STERAPORESUNTM
membrane unit
Specification of the Sterapore SUR(TM) membrane elementsModel number
Model number SUR234L SUR334LB
Membrane surface area 1.5m2 3m2
Pore size 0.4microm
Membrane outer diameter 0.54mm
Element size (mm) 1,035×446×13 1,035×524×13
Dry weight 0.6kg 0.64kg
Materials Hollow-fiber membrane Polyethylene
Collecting water pipes ABS resin
Potting material Polyurethane resin
Specification of the Sterapore SUN(TM) membrane units

Model number SUN21034AAD7
(SUN10534AD7)
SUN21034LAN
(SUN10534LN)
SUN21034LAP
(SUN10534LP)
SUNAAD7
(SUNAD7)
Compatible element SUR334LA *(SUR234L) -
Pore size 0.4microm -
Size
(DWH, mm)
725×1,538×1,442
(678×1,538×1,442)
614×1,538×1,092
(536×1,538×1,092)
614×1,538×1,442
(536×1,538×1,442)j
711×1,538×350
(673×1,538×350)
Weight** 184kg(175kg) 142kg(140kg) 157kg(155kg) 42kg(35kg)
Membrane surface area 210m2(105m2) -
Material of water collecting pipes ABS resin -
Frame material SUS304
Normal operating temperature 0~40°C
Standard treatment volume*** 52m3 per day (26m3 per day) -
Standard water flow rate 66~99Nm3per hour (57~84Nm3 per hour)
Notes With rubber slit air diffuser Without air diffuser
For upper layer
With hollowed polyvinyl
chloride pipe type air diffuser
Rubber slit type
Air diffuser unit
* The standard model uses the SUR334LB.
** Dry weight
*** Assuming the treatment of domestic wastewater in an operation that complies with that described in our operating manual

Features of the SteraporeSADF(TM) series
Designed for large-scale wastewater treatment, such as in public sewerage systems
(hundreds to hundreds of thousands of m3 per day)
Applicable to domestic and industrial wastewater treatment
Uses PVDF hollow-fiber membranes
(SADF membranes)
High permeability
High chemical resistance
Excellent strength
Magnified image of the surface of the SADF membrane made of PVDF
STERAPORESADFTM
membrane element

STERAPORESADFTM membrane unit
Specification of the SteraporeSADF(TM) membrane element
Model number SADF2590R
Membrane surface area 25m2
Pore size 0.4μm
Membrane outer diameter 2.8mm
Element size (mm) 2,000 × 1,250 × 30
Dry weight 16kg
Materials Hollow-fiber membrane PVDF
Water collecting block ABS resin
Potting material Polyurethane resin
Strut SUS 304
Specification of the SteraporeSADF(TM) membrane unit
Model number SAA50090APE06
Compatible element SADF2590R
Number of elements 20
Membrane surface area 500m2
Standard treatment volume* 400m3
Unit size (mm) 1,553 × 1,443 × 3,124
Dry weight 800kg
Frame material SUS 304
Normal operating temperature 0 ~ 40°C
Notes With air diffuser
* Assuming the treatment of domestic wastewater in an operation that complies with that described in our operating manual


2) Kubota

Permeate without SS

The membrane separation system removes not only SS but substances difficult to biodegrade such as detergent, by taking advantage of its longer SRT (Sludge Retention Time). Nutrients such as nitrogen and phosphorus can also be cleared. This enables the treated water to be re-used.

Simple Maintenance

Volume control of return sludge or microscopic observation of the microorganism is not necessary. All that is required control of trans-membrane pressure and basic water analysis, both of which can be easily learned. Telemetry is easily applied.

Energy Conservative Operation

KUBOTA Submerged Membrane Unit system is designed for energy conservation. Aeration plays two roles to save energy; oxygen supply for biological treatement and cleaning of membrane surface with turbulent flow.

Remarkably Small Footprint

KUBOTA Submereged Membrane Unit is installed in an aeration tank. Since it carries out high-concentration activated sludge treatment, no settling tank or sludge concentration tank is required. The size of the aeration tank is also minimized.





3) ..........