Sea Water Desalination:

img3 Is a process of removing some amount of salt and other minerals from saline water (sea water), and having as goal the production of fresh (drinking) water which is suitable for human use.
The composition of the sea water in the glob differ from a geographic locality to another, this difference concerns the particulars composing the sea water.

Three phases of this process, are distinguish and must be respected to have a good quality of drinking water.

Desalination Process - Phases:
1- The pretreatment phase:
Includes all the necessary treatment tasks ahead of the entry of the water in a water treatment unite. It is determining for unite life time and to minimize chemical cleaning and membrane replacement. It has a direct impact on the unite performance. The kind of pre-treatment system that is used greatly depends on feed water quality. Consequentially, sufficient feed water pre-treatment is dependent on:

  • The source of the feed water
  • The composition of the feed water
The analysis and specification of the source of the feed water determines the design of a pre-treatment system and the entire water treatment unit composition.
In order to reduce the fouling of the membranes' unites, it is recommended that, we apply the appropriate Pre-treatment as mentioned below:

Fouling type
Cause
Pre-treatment
Biological fouling
Bacteria, microorganisms, viruses, protozoan
Chlorination or Chlorine dioxide
Particle fouling
sand, clay (turbidity, suspended solids)
Filtration
Colloidal fouling
Organic and inorganic complexes, colloidal particles, micro-algae
Coagulation + Filtration
Optional: Flocculation / sedimentation
Organic fouling
Natural Organic Matter (NOM) : humic and fulvic acids, biopolymers
Coagulation + Filtration + Activated carbon adsorption
Coagulation+ Ultrafiltration
Mineral fouling
Calcium, Magnesium Barium or Strontium sulfates and carbonates
Antiscalant dosing
Acidification
Oxidant fouling
Chlorine, Ozone, KMnO4
Oxidant scavenger dosing:
Sodium (meta)bilsulfite
Granulated Activated Carbon


Killing bacteria and microorganism before entering the membranes will prevent biofouling.

Chlorine dioxide (CLO2) : it gets the job done where others fail
Is one of the best chemical disinfectants used in pretreatment phase, it removes the biofilm and kills the bacteria, spores and viruses.  
Other advantages are:  
  • The bactericidal efficiency is relatively unaffected by pH values
    between 4 and 10;
  • The required contact time for ClO2 is lower;
  • Chlorine dioxide has better solubility;
  • Chlorine dioxide does not react with NH3 or NH4+;
  • It destroys THM precursors and increases coagulation;
  • ClO2 destroys phenols and has no distinct smell;

2- The Ultra filtration Phase:

This is the second phase of sea water treatment, it is an important phase allowing you the separation of suspended solids, bacteria and virus and colloids.
The efficiency of this phase is completely based on the membranes' pores .
The best membranes which we advise to use in this phase are ceramic Membrane having pores between 1 to 5 nm.

Ceramic membranes

img1 It provide high flows, minimizing the fouling phenomena. Furthermore, they are susceptible of being regenerated with a wide range of chemicals, and chemical cleaning conditions.
Moreover, they are resistant to solvents, oxidizers and other chemical products; they support all the pH range and temperature up to 100°C.
Because of their material and configurations, they can filter fluids with high concentration for oil, suspended solids and high viscosity.
As a result, the membrane is suitable for the filtration of any kind of water, liquid wastes, leachate, chemical, pharmaceutical, paper mill, petrochemical and agro-food industries, and in general, any type of industrial filtration.

Ceramic membranes' Advantages

img1 Ceramic membranes are high-quality and long lasting, resistant to difficult fluids, and able to operate in a wide range of conditions. Moreover, Likuid ceramic membranes provide the following advantages:
1- Optimum permeate quality: the high quality of the supports, along with the multiple layers depositions process, allows to obtain always the appropriate permeate quality, avoiding the appearance of cracks and micro breaks which could contaminate and deteriorate the permeate.
2- Reliability: membranes are manufactured following a rigorous quality control, using powders of a controlled granulometry and obtaining the maximum homogeneity in the pore size.
3- Minimum fouling: thanks to the ceramic material and the latest fabrication techniques, the suitable hydrophilicity degree is achieved, so that the deposition of molecules on the membrane surface and the biofouling processes are reduced, thus minimizing the fouling phenomena.
4-Easy regeneration: the ceramic materials used allow to carry out aggressive regeneration, chemical cleanings, with caustic soda, acids, and other specific products at high temperatures. Thus, severe fouling that has been generated in intensive industrial processes can be efficiently recovered, extending the membrane lifetime and minimizing the maintenance requirement... Read More

3- The Reveres Osmosis phase

img1 RO Phase: Reverse Osmosis (RO) is a separation process that uses pressure to force a solvent (water) through a membrane, which retains the solute (contaminant) on one side and allows the pure solvent (water) to pass to the other side.
More formally, it is the process of forcing a solvent from a region of high solute concentration through a membrane to a region of low solute concentrate by applying pressure in excess of osmotic pressure. This process is the reverse of the normal osmosis process, which is the natural movement of solvent from an area of low solute concentration, through a membrane, to an area of high solute concentration when no external pressure is applied. The membrane here is semi-permeable, meaning it allows the passage of solvent (water) but not of solute (contaminant).
Reverse osmosis removes salt and most other inorganic material present in the water and everything larger than the water molecule itself like bacteria, salts, sugars, proteins, particles, dyes, and other constituents.

Reveres Osmosis - Membranes (filters) cleaning.

RO membranes can become polluted after extended use and lose their effectiveness. One of the critical point during this phase is the cleaning of the membranes.
Cleaning the RO filter is a short and simple process that requires only the proper cleaning fluid. Cleaning frequency varies, but most filters require it only once or twice each year With our method of sea water ultra filtration, the water arrive to the RO membranes enough clean which allows you to be quite about the quality of your potable water and the cleaning of your RO membranes.
The above advantage is, only, one of the multiple advantages of using OGINATEC sea water unites and process
Let us take care about your desalination and quality of potable water.

OGINATEC's Water desalination System
Advantages

Our combination between an high tech and advanced nano technology as ultra filtration process, based on specific ceramic membranes, and the classic RO system, OGINATEC Process allows you to take commercial advantages and an excellent quality of drinking water.
Some advantages of OGINATEC's process,

  1. By the reducing of an important tasks of your classic desalination process, you will be able to have an excellent ROI (Return Of Investment), this economy is calculated in terms of Human Capital (effected tasks) and in terms of number of machines or pretreatment phases.
  2. Minimize the risk of used chemical products and gain their cost.
  3. The obtaining of an excellent quality of drinking water, which can be consumed without any extra-treatment.
  4. The reduction of energy and pollution
  5. Thanks to the use of a revitalization process, you obtain, not only a drinking water, but a revitalized water.