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| Organic polymeric membrane |
The generic name of the membrane which assumes organic matter material. It is also known as polymer membrane. |
| Microfiltration membrane | A separation membrane with a pore diameter of about 0.05㎛ - 10㎛. It is mainly used to remove fine particles and bacteria. It is aimed for water purification and is utilized in many scenes of processing a large amount of water including pretreatment, desalination, the sewerage treatment. |
| Ultrafiltration membrane | A separation membrane with a pore diameter of about 2㎚ - 0.05μm. It is possible to remove fine particles and bacteria, macromolecule. It is used to remove the parasitic protozoan, bacteria and Viruses. |
| Nano filtration membrane |
A separation membrane with a pore diameter of about 1㎚ - 2㎛ which used for nano filtration. It is possible to remove smaller particle and polymer compared with Ultrafiltration membrane. It is used to remove scale components and divalent ion such as sulfate ions, and hardness components. |
| Reverse osmosis membrane |
A separation membrane with a pore diameter of under 1㎚ that used for reverse osmosis filtration. It is possible to remove ion molecules. It is used for desalination of seawater or production of pure water and ultra-pure water. |
| Solid Liquid Separation | Separating a suspension (solid particles mixed, dispersed, or suspended in a liquid) into liquid and solid. |
| Membrane Bioreactor | One of the activated sludge processes. A method of water processing which separate sludge and treatment water by membrane instead of final settling tank. Compared with standard activated sludge process, it is easier to management and maintenance because of stable water quality. Also, it is possible to save space because the method does not need the Sedimentation tank. |
| Submerged MBR, Immersed MBR |
The process of immersing a membrane filtration device in a bioreactor and filtering only clear water from the outside to the inside of the membrane by the pressure difference between the inside and outside of the hollow fiber membrane caused by filtration pumps and water level differences, in order to obtain clarified water. |
| Side stream MBR, External MBR |
One of the Membrane Bioreactor process that set the membrane out of the biological treatment tank and passing water to the membrane with pressurizing the sludge by the pomp. |
| Aerobic treatment | A method of purifying organic matter in wastewater through the activity of aerobic microorganisms (microorganisms that thrive in the presence of oxygen) under the presence of oxygen. The activated sludge process is a typical example of Aerobic treatment. |
| Anaerobic treatment | A method of purifying organic matter in wastewater using anaerobic microorganisms (microorganisms that can live in the absence of oxygen). Methane fermentation (anaerobic digestion) is a typical example of anaerobic treatment. |
| Aeration | In the activated sludge process, supplying air to the aeration tank to provide oxygen. |
| External pressure type, Out-in type |
A filtration method that supply water is passed through the outside of a hollow fiber membrane to obtain treated water on the inside. |
| internal pressure type, in-out type |
A filtration method that supply water is passed through the inside of a hollow fiber membrane to obtain treated water on the outside. |
| dead-end filtration | A filtration method that the filtrate is passed through the membrane surface vertically while being filtered. This method does not require parallel flow, resulting in reduced energy costs. |
| Cross-flow filtration | A filtration method that the filtrate is passed parallel to the membrane surface while being filtered. This method suppresses the deposition of particles on the membrane surface by creating a parallel flow to the membrane surface. |
| Flux | The membrane filtration rate per unit membrane area and per unit time. Typically, one of the following is used. (1) The liquid volume that passes through per day per membrane area of 1 square meter. It is represented as [㎥/(㎡･d)] or [m/d]. (2) The liquid volume that passes through per hour per area of 1 square meter. It is represented as [LMH]. |
| Trans Membrane Pressure |
The pressure to the membrane. Difference between the side of supply water and treated water of the membrane. |
| Scale | The deposition of insoluble substances from the water, which become more concentrated due to concentration, exceeding their solubility, on the membrane surface or other locations. |
| Fouling | A phenomenon in which substances present in the supply water are trapped by the membrane, leading to clogging and the formation of fouling layers on the membrane surface and within the membrane pores, resulting in a decrease in membrane performance. |
| Backwash | Backwashing refers to the process of pushing water or air from the side of treated water to the side of supply water of the membrane under pressure to remove fouling substances that have adhered to the membrane. |
| CIP (Cleaning In Place) | A method of cleaning membranes without removing them from the system, while they are still installed in place. |
| OLC (Off Line Cleaning) | A method of cleaning membranes by removing the membrane unit from the system. |
| SS (Suspended solids) | An indicator of water turbidity. They refer to the particle-like substances with a diameter of 2 mm or less that are floating or suspended in water. They are also known as particulate matter. |
| BOD(Biochemical Oxygen Demand) | An indicator used to measure the contamination or impurities caused by organic matter in water. It represents the amount of oxygen required by microorganisms to decompose organic matter present in water. |
| COD(Chemical Oxygen Demand) | An indicator used to measure the contamination or impurities caused by organic matter in water. It is also known as oxygen demand. It represents the amount of oxygen required to oxidize the oxidizable substances present in water. |
| SDI (Silt Density Index) |
One of the indicators for trace levels of turbidity in water. It is used as an indicator for the turbidity present in the supply water in reverse osmosis treatment. It is also referred to as the Fouling Index (FI). |
| MLSS (Mixed liquor Suspended Solid) |
The concentration of activated sludge in the aeration tank. It is measured in mg/L. It represents the concentration of organic matter and other substances in the mixed liquor in the aeration tank and is also used as an indicator of microbial concentration. |
| Chromaticity | An indicator that expresses the degree of color of substances that are dissolved or exist in a colloidal state in water, ranging from pale yellow to yellow-brown. |
| Turbidity | An indicator that represents the degree of cloudiness or haziness in water. |
| Hydrophilicity | The property of having a high affinity for water and being easily dissolved or mixed with water. |
| Hydrophobicity | The property of having a low affinity for water and being difficult to dissolve or mix with water. |
| Discharge Standards | The permissible concentrations of hazardous substances and other pollutants in wastewater. They are typically set to regulate the discharge of wastewater from sources in order to achieve environmental standards for water pollution. The applicable operators have an obligation to comply with these standards, and penalties may be imposed in the event of non-compliance. |
| Pure water | Water with low impurities and high purity. It typically refers to water that has had almost all salts, organic matter, and other impurities removed. Generally, pure water has an electrical resistivity of 0.1 to 1.5 MΩ･cm. |
| Membrane Distillation | A technology that utilizes the difference in boiling points between the target substance in the supply water and the liquid to pass vapor through a membrane. |
