Exploring Water Purification Technologies: Common Methods and Their Pros and Cons

As environmental pollution continues to worsen and awareness of health concerns rises, water purifiers play an increasingly crucial role in today’s household life. However, with a multitude of water purifier types and various purification technologies flooding the market, ordinary consumers may find it somewhat challenging to choose a water purifier that suits their household needs. This article will delve into common water purification methods to help readers gain a more comprehensive understanding of water purifier technology and its pros and cons.

1. Reverse Osmosis Technology (RO)

Reverse Osmosis (RO) technology is a method of filtering impurities from water through a semi-permeable membrane. This technique effectively removes heavy metals, bacteria, viruses, and most dissolved harmful substances in water. The semi-permeable membrane used in the RO process is a special porous membrane with extremely small pores, typically around 0.0001 micrometers. This allows the membrane to efficiently block dissolved salts, organic compounds, bacteria, viruses, and the majority of other pollutants, while allowing water molecules to pass through these tiny openings. RO is considered a comprehensive water purification method suitable for addressing various water quality issues.

Despite the excellent pollutant removal capabilities of reverse osmosis (RO) technology, one of its drawbacks is the relatively high energy consumption. To propel water through the semi-permeable membrane, RO systems require the application of a certain amount of pressure. This is typically achieved by applying high pressure during the process of water flowing through the membrane. The necessity for high pressure results in the consumption of a significant amount of electricity by RO systems. Additionally, the RO process generates a certain amount of wastewater, which needs proper treatment to minimize environmental impact.

Simultaneously, RO technology also removes some beneficial minerals from water, such as calcium and magnesium. To address this deficiency, some RO systems are equipped with post-filters, incorporating mineralizing balls or alkaline filter materials to reintroduce minerals into the water.

Overall, reverse osmosis (RO) technology is a powerful water purification method, particularly suitable for situations that demand highly purified water, such as laboratories and the pharmaceutical industry. For household purposes, consumers should pay attention to the energy efficiency of the RO system, the wastewater treatment method, and the potential loss of minerals when selecting an RO water purifier. This ensures that the chosen water purification device meets the specific needs of the household.

2. Activated Carbon Adsorption Technology

Activated carbon adsorption technology is a common water purification method that primarily relies on activated carbon materials to adsorb organic substances and odors in water, thereby improving water quality. The principle of activated carbon adsorption is the adhesion and retention of substances on its surface, rather than through chemical changes. When water passes through an activated carbon filter, organic substances and other pollutants are adsorbed onto the surface of the activated carbon, thereby purifying the water.

Activated carbon is a carbon material with a highly porous structure, providing an exceptionally large surface area. These tiny pores and surface area offer sufficient adsorption capacity, allowing activated carbon to effectively adsorb organic substances and odors in water. It is primarily used to remove organic materials in water, such as residual pesticides, drugs, organic pollutants, as well as odors and residual chlorine. This makes activated carbon water purifiers an effective means of improving the taste and odor of drinking water.

Activated carbon water purifiers function by utilizing the adsorption properties of activated carbon to eliminate odors, residual chlorine, and other organic substances in water. While this technology has relatively low costs and yields certain water quality improvement effects, the adsorption capacity of activated carbon is limited. Once saturated, the carbon filter needs replacement or regeneration. Therefore, regular replacement of activated carbon filters is a crucial step in maintaining their effectiveness.

In practice, in household water purifiers, activated carbon is often just one component of the filtration system. Typically, for better protection of drinking water health, a combination of RO, activated carbon, PU, and PV filtration technologies is applied. The safer water purifiers generally have a greater variety of filter types. Most of AquaLinf‘s water dispensers and water purifiers come equipped with four optional filter types, and the filters can be replaced regularly, ensuring the health of household drinking water.

3. Ultraviolet Disinfection Technology

Ultraviolet (UV) disinfection technology is an efficient water purification method that utilizes ultraviolet light (UV-C wavelength) to eliminate microorganisms in water. The wavelength of UV-C falls within the range of 200 to 280 nanometers. UV-C light can penetrate the cell walls and membranes of microorganisms, reaching the nucleic acid molecules, such as DNA and RNA, causing destructive effects on these molecules. This impact results in mutations in the genetic material of microorganisms, preventing their reproduction and growth, ultimately leading to the death of the microorganisms.

Ultraviolet disinfection technology exhibits high efficacy in killing bacteria, viruses, algal spores, fungi, and other microorganisms. It is a broad-spectrum disinfection method, capable of eliminating common waterborne pathogens and combating microorganisms that may be resistant to traditional disinfection methods. In comparison to some chemical disinfection methods, ultraviolet disinfection is a chemical-free, physical treatment method. This means that during the UV treatment process, no chemicals are introduced into the water, thus avoiding secondary pollution to water quality and the environment.

However, ultraviolet light can only act as a germicidal agent and has limited effectiveness in removing certain chemicals and heavy metals. Additionally, the presence of turbidity and organic substances in water may potentially impact the permeability of ultraviolet light.

4. Ceramic Filtration Technology

Ceramic filtration technology is a water purification method that utilizes porous ceramic materials for physical filtration. This technology, known for its simplicity and reliability, has found widespread application in various water purification devices. Ceramic filters are typically made from porous ceramic materials with very small pore sizes, usually ranging from 0.1 to 0.5 micrometers. These tiny pores effectively block particles, bacteria, viruses, and other larger contaminants in water, achieving the desired physical filtration effect.

Ceramic filters are primarily used to remove larger particles such as sediment, rust, and suspended solids, while also demonstrating some effectiveness in removing smaller microorganisms like bacteria and cysts. However, when it comes to substances dissolved in water, the removal efficiency of ceramic filters is relatively weak.

Ceramic filters typically have a long lifespan. Due to the robust nature of ceramic materials and their ability to withstand high water pressure, they are less prone to damage. Additionally, ceramic filters can be repeatedly cleaned and regenerated, extending their operational life. Because of their simple design and reliable filtration performance, ceramic filters are commonly employed in portable water purification devices for outdoor activities and in home water systems in remote areas.

5. Electrolysis Water Technology

Electrolysis water technology achieves the removal of dissolved substances in water through the process of electrolysis, involving oxidation-reduction reactions. This technology is based on the fundamental principles of electrolysis. In an electrolytic cell, water molecules (H2O) undergo decomposition into hydrogen gas (H2) and oxygen gas (O2) under the influence of an electric current. This process occurs at the electrodes and is typically divided into two reactions:

At the cathode (negative electrode):

2H₂O+2e^– → H₂+2OH^–

At the anode (positive electrode):

2H₂O → O₂+4H⁺ +4e^–

Electrolysis water technology not only generates hydrogen gas and oxygen gas but also involves the production of hydroxide ions (OH^-) throughout the electrolysis process, contributing to the alkalinity regulation of water. These hydroxide ions can undergo oxidation reactions with organic substances in water, leading to the decomposition and removal of some organic pollutants. Due to the hydroxide ions and oxygen produced by electrolysis, these substances exhibit a certain bactericidal and microbial inactivation effect. Therefore, electrolysis water technology also has a certain effectiveness in eliminating bacteria, viruses, and other microorganisms in water.

While electrolysis water technology is a promising water purification method, one of its challenges is its relatively high energy consumption and equipment costs. The process requires a significant amount of electrical current for water electrolysis, leading to substantial power consumption. Additionally, the manufacturing and maintenance costs of the equipment are relatively high.

In summary, different water purification technologies have their pros and cons. When selecting a water purifier, it is essential to consider household water needs, water quality conditions, and personal financial capabilities. Consumers should comprehensively evaluate various factors based on their specific situations and choose products with high cost-effectiveness. AquaLinf can tailor a home water purification solution based on your needs, incorporating suitable filtration technologies. Furthermore, regular maintenance of the water purifier is crucial to ensuring stable water quality, with a particular emphasis on the proper use and timely replacement of filters for optimal performance and the delivery of safe, healthy drinking water to the home.