EDI

Traditionally high purity water is produced by a combination of membrane separation and ion exchange processes. Electrodeionization (EDI) is an electrically-driven water treatment technology that utilize ion exchange membranes and resin to remove ionized species from water by electrical driving force,

An EDI stack has the basic structure of a deionization chamber.  There is an ion exchange resin between two selective membranes. The membranes are ion selective and pass only specific charged ions.   As water flow into the EDI module applied electricity makes ions to move through the resins and across the membranes.  Therefore, water is deionized as the ions can pass through the membrane. These ions are collected into concentrate channel and remove from the system.

In comparison to more traditional ion-exchange process, EDI can provide a better energy consumption and operating expenses for high purity water treatment system in a constant flow. EDI has a continues and simple operation and there is no need of acid and caustic chemicals for regeneration. EDI requires little space and very few automatic valves or complex control sequences that need supervision by an operator

Applications

EDI can be used in any application that requires pure water for such as application as following

  • Pharmaceutical industry
  • Boiler feed water
  • Demineralized water
  • Biotechnology
  • Electronics
  • Laboratories
  • Pharmaceutical industry
  • Reduction of ionizable SiO2 and TOC

Ceramic Membranes

Unlike conventional membrane which are from polymer, ceramic membranes are made of inorganics such as alumina, zirconia oxides, silicon carbide and etc.  Ceramic membrane normally has an asymmetrical structure with porous support active membrane layer. Ceramics membrane can categorize based on different modules into flat membranes, roll membranes, hollow fiber membranes, and tubular membranes.

The membrane modules can withstand harsh operating condition such as  high temperatures, extremes of pH (0 to 14), and elevated operating pressures up to 10 bar. This makes these membranes fit for many applications where polymeric and other inorganic membranes cannot be utilized. Furthermore, ceramic membranes are ideal for in-place chemical cleaning at high temperatures, while using caustic, chlorine, hydrogen peroxide, ozone and strong inorganic acids, and/or by using steam sterilization.

* High resistance on acid and alkali condition.
* Long operating life which is 2-3 times longer than polymeric membrane
* Extensive application range of water temperature.
* Environmentally friendly, can be recycled as a raw material for ceramic products.
* Good hydrophilic, low operating pressure, saving energy.
* High flux

Applications

Ceramic membranes are widely being used in a broad range of industries such as biotechnology and pharmaceutical, dairy, food and beverage, as well as chemical and petrochemical, microelectronics, metal finishing, and power generation.

Water Purification

Waste Water Treatment

Chemical Industry

Food and Beverage

Application in municipal water treatment

Application in domestic sewage treatment

Application in oily wastewater treatment

Application in textile wastewater treatment

Application in printing and dyeing wastewater treatment

Application in chemical wastewater  treatment

 

Pressure Vessel

A pressure vessel holds the reverse osmosis membrane elements,  it is also called pressure tube when membranes are spiral wounded. A typical RO pressure vessel can contain  six membrane elements.  Pressure vessel is important part of RO process as it is to handle membranes in high pressures. The pressure vessel contain permeate ports at terminal points.

Watersafe is proud distributor of  the high quality pressure vessels that are planned to handle the highest pressure required by membranes . These pressure vessels are strengthened by durable fiberglass and incorporate end caps for durability.

 

Watersafe is the distributor pressure vessels of following manufactures

 

Hebei Chengda Huamo Technology Co., Ltd.

VETEC

 

 

 

ED/EDR

Electrodialysis is a membrane-based process that uses electrical driving force. In this process by using alternating Anion–selective membranes (AMs) and Cation-selective membranes (CMs), situated between an Anode (+) and a Cathode (-), the separation of ions happens. Applied electric field, anions and cation will move towards the Anode and Cathode, respectively.  Anions are stopped by the CMs and the cations by the AMs, creating a process low ion concentration flow (Dilutant) and a process flow with high ion concentration  (Concentrate).  The process is shown in the below figure.

In electrodialysis, the charged suspended solids increase the resistance of the membrane dramatically, are deposited on the membrane surface over the time.  By reversing the polarity of the applied electrical potential in certain time intervals can eliminate to a large extent by reversing will result in a removal of charged particles that have been precipitated on the membranes. This technique is referred to as electrodialysis reversal (EDR).

 

Application

 

  • Large scale brackish and seawater desalination and salt production.
  • Small and medium scale drinking water production such as towns & villages, construction & military camps, nitrate reduction, hotels & hospitals.
  • Pre-demineralization such as  boiler makeup & pretreatment, ultrapure water pretreatment, process water desalination, power genration
  • Food processing and agricultural water  for greenhouses  livestock and irrigation
  • Glycerin purification

 

WaterSafe is a distributor of GE Aquamite* EDR Systems

Membrane Separation

Membrane separation is promising technology in water and wastewater for conventional and emerging contaminates. are classified, based on the type of driving force they use. The different type of driving force that separate   the water includes: a pressure differential and reverse ; and a electrical force with to an ion exchange that facilitate migration of ions through the, electro and electrochemical devices).

Based on the pore sizes the Pressure-driven membrane processes are divided into reverse osmosis (RO), microfiltration (MF), nanofiltration (NF) and ultrafiltration (UF). In Figure 1 the different type of membranes and their mechanism are shown.

The selectivity between MF and UF is typically based upon pore size number (diameter of the micropores in a membrane surface) or molecular weight cut-off (MWCO) number. Reverse Osmosis also can be used to desalinated water as well as other contaminates.

 

 

Electrically driven (ED) membrane processes, commonly used in water/waste water treatment, also include electrically driven reversal (EDR) membrane processes. ED and EDR use a difference in electrical potential to induce dissolved ions to migrate through a water-impermeable membrane. This reduces their concentration in the feed water.

The anions (negatively charged ions) move in the direction of the positively charged electrode (anode) and are transported through the anionic membrane, but are restrained at the surface of the cationic membrane. The end result is a ‘dilute’ stream with a reduced salt concentration and a concentrate stream with a higher salt content than the feed water.

Choosing the Right Membrane

Membrane technology selection should be based on type of water and the treatment objectives at the lowest possible cost. In the following Table , typical pressure driven membrane process and application are shown.

Watersafe is an expert in design, procurement and installation of different membrane technologies.

Process TARGET COMPONET PERATING PRESSURE PROCESS APPLICATION
RO 99% of most ions, most organics over 150 MW 15-70 bars Brackish sea water, desalting, boiler feed, purification, pre-treatment to ion-exchange,
NF 95% divalent ions, 40% of monovalent ions, organics greater than 200-300 MW 9- 20 bar Hardness removal, organics and microbiological removal, dye desalting, color removal
UF Most organics over 1000 MW 2-9 bars Pre- and post-treatment to IX, beverage clarification, removal of pyrogens, bacteria, viruses and colloid, dilute suspended oils
MF Small suspended particle greater than 0.1mm 1.5-4 bars High volume of removal of suspend solids

 

Our Services

We are a global supplier of water and wastewater system, equipment and materials. We will be a with you from construction, commissioning and operation.

Contact Us

About Us

Watersafe is a global water treatment company based in Ontario, Canada and was established in 2003. With close to two decades of experience in industry, Watersafe is specialized in design, construction, and operation of municipal and industrial treatment processes, desalination systems, wastewater recycle and reuse, plant recommissioning and maintenance, and troubleshooting. Additionally, the company provides water and wastewater treatment equipment and supplies, chemicals, instrumentation, piping and fittings for each application.

 

Watesafe has successfully provided industry specific water and wastewater treatment solutions for municipal and industrial applications with more than hundred completed projects for a wide range of clients including but not limited to:

  • Oil and gas
  • Petrochemical and refining
  • Chemical manufacturing
  • Pharmaceuticals
  • Steel manufacturing
  • Food and beverage
  • Automotive

Watersafe is dedicated to providing the best customer service by delivering the most valuable solutions to your treatment needs.

 

Toray

Dow