Description
Any membrane system such as the RO system is naturally clogged by the presence of suspended substances, soluble solutes and microbial parameters in the feed water, which necessitates proper physical and chemical pre-treatment of the system.
Scale and clogging can reduce the effective spacing between the materials and reduce the flow turbulence that results to increased concentration polarization on the membrane surface. The higher the solute concentration at the membrane surface, respectably, more solute pass through it. When the effective surface area of the membrane is reduced, turbulence will be reduced and the surface of the membrane will be more difficult to clean, because the possibility of sending the solution to the blocked surfaces (by solids) is reduced, thus preventing from scale formation by proper system efficiency and chemical injection is one of the obvious principles of RO systems.
Inhibitors reduce the deposit process rate by preventing salt crystal growth. These substances are adsorbed on the crystal surface of the salt, and they reduce the rate of salt crystal spreading by preventing the absorption of more supersaturated salt on the crystal surfaces and thus the primary crystal core never reach a sufficient size or concentration for deposition.
Most scale inhibitors have a molecular structure with functional groups including carboxylic acid (-COOH) or phosphate. Low molecular weight polyacrylate molecules (molecular mass between 100-5000) contain several carboxylic acid functional groups and are commonly used in many inhibitors. These inhibitors are among the best in preventing the formation of sulfate and carbonate, but their dispersing properties are limited; therefore, the use of mixture inhibitors exhibits better results than single-molecule inhibitors. If used a single-molecule inhibitor, the over-injection of the inhibitor is more likely to cause the inhibitor to exit as a multivalent cation. By combining products and the use of multi-molecular inhibitors, other inhibitors can be effective in preventing the deposition of the first inhibitor. It will also require less concentration than any of the independent components of the inhibitors.
Abrizan Industrial Research Company with a long background in the field of antiscalant production to improve the performance of R.O devices and extend the useful life of membranes has begun to produce a new type of Polymer-based combinatory antiscalants.
Advantages of Polymeric Antiscalants:
- High concentrations.
- Does not allow deposition of any types of carbonate and phosphate scales.
- Used and formulated for a wide range of waters including seawater, wells saltwater, freshwater with hardness, waters with hardness below 1000ppm.
- It performs better due to its high chelating ability.
- Good dispersant performance against carbonate and sulfate scales.
- Membranes need to be cleaned over longer period of time.
- Reduces the growth of algae and biological pollutants.
Calibration of Using Polymeric Antiscalants:
The amount of antiscalant injection depends on the parameters such as water analysis, flow rate, temperature, pH, system recovery rate, water source, type of membrane and how the membrane is arranged. Typically, the rate of injection of antiscalants is in the range of 2-8ppm.
Introduce & Calibrate of Using Polymeric Antiscalants | ||||
Some physical properties | Dosage | Type of use | Antiscalant code | |
Mode: Amber liquid with mild odor Density at 20˚C (gr⁄ml): 1.068 pH ˃2 boiling Temperature Range (˚C): 96 – 99 Freezing temperature range (˚C): -5 – -2 Solubility in water: dissolves rapidly | 3-8ppm | sea water | Mitreh APA70 | 1 |
Mode: Amber liquid with mild odor Density at 20˚C (gr⁄ml): 1.071 pH ˃2 boiling Temperature Range (˚C): 95 – 99 Freezing temperature range (˚C): -6 – -2 Solubility in water: dissolves rapidly | 3-8ppm | Brackish water | Mitreh APA69 | 2 |
Mode: Amber liquid with mild odor Density at 20˚C (gr⁄ml): 1.059 pH ˃2 boiling Temperature Range (˚C): 94 – 98 Freezing temperature range (˚C): -3 – -1 Solubility in water: dissolves rapidly | 3-8ppm | Saline water +1000ppm | Mitreh APA61 | 3 |
Mode: Amber liquid with mild odor Density at 20˚C (gr⁄ml): 1.056 pH ˃2 boiling Temperature Range (˚C): 97 – 99 Freezing temperature range (˚C): -4 – -2 Solubility in water: dissolves rapidly | 2-6ppm | Waters with hardness -1000ppm | Mitreh APA56 | 4 |
Mode: Amber liquid with mild odor Density at 20˚C (gr⁄ml): 1.066 pH ˃2 boiling Temperature Range (˚C): 98 – 99 Freezing temperature range (˚C): -6 – -2 Solubility in water: dissolves rapidly | 3-8ppm | Waters with hardness +2000ppm | Mitreh APA65 | 5 |
Calculation of Antiscalant Dosage for One Day:
Diluted the amount of antiscalant used for one day according to the instructions of the technical office experts between 20 to 1000 liter tanks with R.O water and inject by dosing pump.
Reviews
There are no reviews yet.