Plate Tube System (Pt/Dt Module) For Ro/Nf
Rochem's Plate Tube Type Membrane Modules has many Operational advantages over the other Membrane Systems available in the market. A flat membrane Module uses patented concept of a membrane cushion stack with completely open feed channels in combination with straight through feed flow.
The vertical placement of Modules in combination with feed air / water flushing allows membrane cleaning and a stable operation for long periods without use of chemical cleaning agents.
"The key for a proper and reliable operation of RO membranes is in the pretreatment".
Conventional technologies may have a number of pretreatment stages as follows:
a. Chlorine dosing
b. Coagulant dosing
c. Polyelectrolyte dosing
d. Coarse Filtration
e. Fine filtration
f. Antiscalant dosing
h. Micron Filtration (Upto 5u)
The above pre treatment is necessitated due to inherent bio-fouling, colloidal fouling and scaling that is prevalent due to the peculiarity of construction of these membrane types.
To overcome these problems which plagued the Reverse Osmosis desalination technology until the mid 1980's, ROCHEM developed their state of art Plate and TubeTM module after considerable research and trials. The main feature of such membrane configuration is the steady continuous waste water velocity over all sections of the membrane surface and the big channels between the membrane and the Plate surface which means an open-channel-operation.
ROCHEM's PT membrane module has been conceived for tackling this exact difficulty of Spiral wound and Hollow film fiber membranes to purify waste water.
Rochem Plate Tube Module
The problems of conventional configurations, the configurations that reflect ease of manufacture rather than operational effectiveness, have been overcome by the state of art Plate and tube membranes module technology in all applications ranging from waste water desalination to industrial waste water treatment.
It is constructed from a series of octagonal membrane cushion separated by a series of plastic spacer Plates. The Plate support the membrane cushions but leaves an open channel flow path through module. The flow path is radial and gets reversed in 180' to flow over other side of cushion. This flow path repeats for each membrane in stack. The resultant turbulence due to reversal eliminates the concentration polarization minimizing scaling & fouling.
Advantages of Constructional Configuration in ROCHEM's Plate Tube Module:
a. Open channel feed flow path
- An Open Channel Feed Flow Path Reduces the need for Pretreatment and Reduces the Possibility of Fouling
- The Plate Tube has an Open Channel of 1mm
- A Conventional Module has a 3 - 7 Micron Channel
- The Plate Tube has 1500% Greater Clearance
- The Plate Tube Allows for More Complete Cleaning
b. Short flow path
- Flow Reversal Causes Turbulence, Turbulence Reduces Polarization Concentration
- The Plate Tube has a 3 Inch Flow Path between Flow Reversals
- A Conventional Module has a 40 Inches Flow Path
c. Minimal areas of no flow
- Zones of No Flow Increase the Rate of Fouling and Catch Bacteria and Colloidal Material
- Contact with the Membrane Creates Zones of No Flow
- The Plate Tube has Minimal Contact with Membrane Surface
- The Feed Spacer In a Conventional Module has Tremendous Contact with the Membrane Surface
Fm Modules - Uf
Rochem - FM modules (Flat-Membranes) have been developed especially for the seperation of bacteria, viruses and fine solids from water and wastewater with a high fouling potential. Most importantly the modules exhibit low specific energy consumption at high and steady state fluxes.
Rochem membrane filtration plants are compact and based on a standardized design. The combination of a hydrodynamically optimised module with a standardized and steadily improved plant design guarantees a high and stable productivity.
Princilple of Ultrafiltration
Ultrafiltration membranes form for bacteria and viruses and a stable operation for long periods without use of chemical cleaning agents. In addition the wide spectrum of commercially available flat sheet membranes for ultra-filtration (UF) allows the optimal selection of a membrane for each individual application.
Ultra Filtration Membrane
Low operating cost
- Safety barrier for pathogenic microorganisms like viruses and bacteria.
- Seperation of colloids and dissolved organics of high molecular weight.
- Long service lifetime of membranes since internal pore blocking is unlikely in case of UF.
- High availability of Units.
Low Investment cost
- Low specific energy consumption.
- Fully automated operation.
- High water recovery rates up to 98%
- Simple pant-assembly
- Simple membrane replacement.
- Standardized plant design
- Optimum material selection(low cost plastic where possible)
- Minimum number of sealings.
- Simple system design by modular construction
Open feedside channel
- Long operation intervals between flushing/ cleaning because of the high module loading capacity for separated solids.
- Straight through flow without dead zones.
- No prefiltration required.
High Degree of flexibility
- Adaptation of feedside clearance (Distance between membrane cushions) to feed concentration
- Wide choice of membranes. (UF,MF,NF)
- Dead end and cross flow operation possible.
- Construction material can be recycled.
- Minimized chemical consumption
- Minimized concentrate disposal bacause of the high water recovery rate.
- Feedside airbubble flushing: high shear stresses of the two phase system air/water.
- Permeate backflushing possible.