DIRECT-RO: Reverse Osmosis for Leachate Treatment

All on-board packaged plants: containerized Reverse Osmosis systems for quick start-up

Typically, leachate from waste treatment, landfills and landfill lagoons is heavily contaminated with organic substances (BOD, COD), nitrogen (mostly ammonia and organically bound nitrogen), heavy metals and salts. Since these compounds have some negative impact on the environment, the leachate needs to be treated before it can be discharged to a water body or the sewers.

A Reverse Osmosis is a basic treatment technology for treating such leachate, used in countless landfills all over the world.

Description of the product

The WEHRLE Direct-RO is a standardized and containerized Reverse Osmosis system for treating leachate directly from the lagoon or landfill. The Direct-RO is designed aiming at compactness, user comfortability and simplicity of the operation as well as the installation.

The Direct-RO is available in three different sizes (S, M or XL) that cover an inlet flow range up to 260 m³/d. Depending on the leachate characteristics and the required discharge quality, 2- or 3-step versions can be selected. With a variety of optional packages, the Direct-RO can be configured to the local needs.

The Direct-RO operates with organic spiral wound (SW) membrane modules in a Feed & Bleed configuration at a pressure of 80 bar. The system has been designed in a way that a possible later upgrade to a WEHRLE BIOMEMBRAT® MBR is possible. This may be an option if e.g. ammonia values exceed normal parameters.

Further variations, plant sizes or features are available on request.

WEHRLE container plant with direct reverse osmosis treatment - Direct RO

Features

  • Highly flexible 80 bar RO system for variable flow rates and high permeate yield 

  • High quality materials and components from brand manufacturers 

  • On-board sand filter unit with automated backwashing 

  • On-board influent pH adjustment system with antifoam control  

  • Chemically enhanced CIP (“Cleaning-in-place”) system 

  • PLC-automated process control equipped HMI with remote access function  

 

 Technical details 

WEHRLE uses selected materials and components suitable to the application from well-known suppliers. The Direct-RO will be delivered as a standard 40’ container(s), equipped with automatization and process control and comes pre-commissioned and tested in our factory.

Container Color: RAL 7035
Pressure: 80 bar
Membranes:

organic, spiral wound, 8” modules

Sub-systems:

automatic pH adjustment, foam control, CIP, automatic sand filter

Measured data (online):

pH, conductivity, temperature, pressure, flow

PLC:

Siemens S7

Operation / HMI:

Siemens touch panel with graphical user interface

Remote processing:

optional, with LAN

Safety equipment:

mobile eye shower

Sulfuric acid storage:

S, XL: inside or outside, M: outside only

 

Leachate treatment with WEHRLE Direct Reverse Osmosis

WEHRLE uses Spiral Wound (SW) membranes:

feed and bleed spiral wound - Direct Reverse Osmosis for leachate treatment WEHRLEspiral wound membrane for Direct RO for leachate treatment - WEHRLE

  • Space-saving due to horizontal construction and high membrane surface. This allows to fit 3 RO steps within one container.

  • With 80 bar process pressure, standard equipment & piping can be used. This reduces the plant operation costs, especially for membrane replacement.

  • The Feed & Bleed configuration allows to vary the flow rate.

Membrane lifetime expectancies:
1st step: 1 … 2 years, 2nd/3rd step: 3 … 4 years.

Available plant sizes

Depending on the flow rate that needs to be treated, there are three different plant sizes of the WEHRLE Direct-RO:​ the S, M and XL plants, which cover a wide range of flow rates. 

WEHRLE - Direct Reverse Osmosis for leachate treatment

            S / M: 1 container 40‘    XL: 2 containers 40‘
*) the higher level (COD or TDS) determines the working point

Recovery rate

Depending on the required rejection rate and the expected inlet TDS concentration, a configuration with 2 or 3 steps can be selected.

The following table shows an overview of the retention rates for Chemical Oxygen Demand (COD), Ammonium (NH4-N) and Total Dissolved Solids (TDS) achieved with a 2 and 3 Direct-RO plant: 

 

Retention rates

Model Selection Steps

COD

NH4-N

TDS

2-step
2-step reverse osmosis plant - WEHRLE

99 %

98 %

99%

3-step
3-step reverse osmosis plant - WEHRLE

99.9 %

99.7 %

99.9%

 

Packages/ Options

The Direct-RO meets and adapts to the clients demands by customizing the plant selecting the required Options / Packages.
This provides a finalized and complete design able to be delivered in a much shorter time.  

Advanced Automation Package containing

  • PLC controlled pressure control valves

  • PLC controlled CIP valves and cleaner pumps

  • Advanced PC based process control system

  • maximized permeate recovery at all times

  • automatic CIP, based on process parameters

  • in-depth evaluation, long-term recording of process data

OPEX Reduction Package containing

  • Additional stand-by sand filter

  • Degassifier column

  • improves plant availability

  • pH adjustment of effluent without need for chemicals

Hazardous Environment Package containing

  • PE lining of container inside

  • Air filter

  • improved corrosion protection and system longevity

  • reduces corrosive and odorous substances in the
    container ambient air

Hot Climate Package for average daily ambient temperatures > 20 °C containing

  • Air condition

  • to keep the inside container temperature below 35 °C

Cold Climate Package for average daily ambient temperatures < 0 °C containing

  • Extra heater

  • Container floor insulation

  • Insulated external piping box

  • to keep the inside container temperature above 5 °C

  • reduce icing of external connections of the container

Basic Chemicals Package (within E.U. only) containing

  • Membrane cleaners

  • Antiscalant

  • Antifoam

  • price on request

2-year Spares Package containing

  • Spare membranes and filters

  • Spare part sets for all pumps

  • Spare probes for essential sensors

  • individual package compiled based on your budget

Extended Warranty Package (only in combination with 2-year Spares Package)

CSC Certification for overseas shipments

 

For more information or individual upgrades please contact us!  
Subject to change without prior notice!