Author: Vanessa 8 Apr. 2025 Category: Applications
Ⅰ. Physical and chemical properties of water
Water (H₂O) is the most common solvent on earth. Its unique physical and chemical properties make it an indispensable resource in industrial production and daily life.
Physical properties:
- High specific heat capacity (4.18 J/g·℃), which can effectively regulate temperature.
- Good solubility, can dissolve a variety of inorganic salts and organic matter.
- The density is maximum at 4℃, and the density of ice is lower than that of liquid water, making ice float on the water surface.
- High surface tension, affecting the stability of colloids and suspended matter.
Chemical properties:
- Neutral (pH=7), but natural water is weakly acidic (pH≈5.6) due to dissolved CO₂.
- It can participate in chemical reactions as an oxidant or a reductant (such as electrolysis of water to generate H₂ and O₂).
- It is easy to form hydrates with metal ions, affecting the hardness of water.
- In the condensate polishing process, these properties of water directly affect the removal efficiency of impurities, so the treatment process needs to be optimized in a targeted manner.
Ⅱ. Impurities in natural water
Natural water is not pure H₂O, but contains a variety of impurities. Taking the Middle East countries and regions as an example, the main problems or treatment solutions that need to be dealt with are divided into the following categories:
- (1) Dissolved solids (TDS, Total Dissolved Solids), including Ca²⁺, Mg²⁺ (causing hardness), Na⁺, K⁺, Cl⁻, SO₄²⁻, etc. High TDS is prone to scaling, affecting heat exchange efficiency, and needs to be removed by ion exchange or reverse osmosis.
- Desalination demand: 70% of drinking water in Gulf countries relies on desalinated seawater, but RO membranes are easily contaminated by silicates and boron and need to be pretreated.
- Brackish groundwater: The TDS of some groundwater in Saudi Arabia and the United Arab Emirates exceeds 10,000 mg/L, requiring electrodialysis (ED) or ion exchange.
- (2) Suspended solids, such as silt, algae, and particulate matter, may clog pipes and filter elements and require mechanical filtration or flocculation and sedimentation to remove.
- Dust pollution: Storms bring a large amount of siliceous particles, which clog the filter element and require self-cleaning filters or centrifugal separation.
- Oil pollutants: The oil industry produces oily wastewater, which requires flocculation separation + activated carbon adsorption.
- (3) Organic matter, including humic acid, grease, and industrial pollutants, may breed microorganisms and require activated carbon adsorption or advanced oxidation treatment.
- (4) Colloids, tiny particles (1-100 nm), such as silica gel and iron colloid, are difficult to settle and require ultrafiltration or chemical coagulation.
- (5) Dissolved Gases such as O₂ (accelerates corrosion), CO₂ (lowers pH), and H₂S (produces odor) require vacuum degassing or chemical deoxygenation.
- (6) Bacteria and microorganisms such as Legionella and algae may form biofilms and require ultraviolet sterilization or chemical disinfection.
In the condensate polishing process, it is necessary to select appropriate pre-filtration technology according to the type of impurities, such as mechanical filtration, ion exchange, membrane separation, etc., and make the following three arrangements:
- Pretreatment: Multi-media filtration + ultrafiltration (UF) to remove colloids/suspended solids.
- Desalination: RO+EDI (electrodeionization) combination to ensure ultrapure water.
- Reuse: MBR (membrane bioreactor) + advanced oxidation treatment of wastewater
Ⅲ. Advantages of Trenntech coalescing filter element in gas dehumidification
In industrial water treatment, liquid water (condensate) in gas (such as compressed air or steam) can cause equipment corrosion, instrument failure and other problems. For example, the high temperature and high humidity environment in the Middle East (such as coastal areas with relative humidity >80%) poses severe challenges to compressed air systems. Trenntech Large capacity filter element element uses advanced materials and structural design, and performs excellently in gas dehumidification:
- High-efficiency separation: through the special fiber layer, tiny droplets (0.1µm) are coalesced into large droplets to achieve efficient gas-liquid separation; oil-water separation for oil-containing compressed air: oil removal efficiency >99.9%.
- Low pressure drop: optimize flow channel design, reduce energy loss, suitable for high-pressure gas treatment, energy saving of more than 30%, suitable for high-electricity price areas in the Middle East.
- Long life: strong anti-pollution ability, long maintenance cycle, and reduced operating costs.
- Widely applicable: can be used for dehumidification and purification of various gases such as compressed air, natural gas, and steam.
- High temperature and high salt resistance design: Made of glass fiber reinforced PP material, it can withstand air intake temperatures above 60°C (common in Middle Eastern air compressor systems). It is resistant to salt spray corrosion and is suitable for harsh environments such as offshore oil platforms and desalination plants.
Water quality testing and fine treatment are key links in industrial water management, and it is necessary to comprehensively consider the physical and chemical properties of water, types of impurities, and high-efficiency filtration technology. The application of innovative solutions such as TrenntechLarge capacity filter element can significantly improve the efficiency of gas dehumidification and ensure stable operation of the system. In the future, as environmental protection standards are improved, intelligent and low-energy water treatment technologies will become an industry trend.