INTRODUCTION

Multi-media filters are widely used and highly effective equipment in the field of water treatment. They mainly consist of a filter tank, multiple filtering media, a water distribution device, a water collection device, and inlet and outlet pipelines.

The filter tank, as the outer shell, provides stable protection and support for the internal components. It is usually made of high-strength carbon steel or stainless steel, possessing good pressure resistance and corrosion resistance. The multiple filtering media are the core elements. Common ones include quartz sand, anthracite coal, and activated carbon. These media are layered and filled in the tank according to certain differences in particle size and specific gravity, forming a multi-layered filtration structure. The water distribution device ensures that the water to be filtered is evenly distributed on the surface of the filtering media, while the water collection device is responsible for collecting the filtered clean water.

This equipment comes in a variety of specifications and can be flexibly selected according to the water treatment volume and water quality requirements. It can range from meeting the water filtration needs of households and small factories on a small scale to being suitable for large-scale water treatment tasks such as municipal water supply and industrial production. Its appearance design is compact and reasonable, easy to install, and the operation is simple and easy to learn. It runs stably and reliably and can continuously and effectively purify water quality, being a crucial part of many water treatment processes.

WORKING PRINCIPLE

The working principle of multi-media filters is based on the coordinated filtration effect of different filtering media. When the raw water enters the filter tank from the inlet, it first passes through the water distribution device, which evenly sprinkles the water on the surface of the top layer of the filtering media.

The water then passes through each layer of different filtering media in turn. For example, the top layer may be quartz sand with a relatively large particle size, which can intercept large suspended particles, sediment, and other impurities in the water. Then, the water flows downward through the anthracite coal with a slightly smaller particle size and lighter specific gravity. The anthracite coal can further remove some smaller particles and part of the organic substances in the water. If there is an activated carbon layer, the activated carbon, with its developed pore structure, will adsorb residual chlorine, odor-causing substances, and some dissolved small-molecule organic substances in the water. In this way, through layer-by-layer filtration, impurities in the water are continuously intercepted and adsorbed when passing through each layer of the filtering media. Finally, the water collected by the water collection device and flowing out from the outlet is relatively pure and meets the requirements, achieving the deep purification of the raw water.

MAIN PERFORMANCE AND CHARACTERISTICS

l High-Efficiency Filtration Effect: Thanks to the combination of multiple filtering media and the reasonable layered structure, multi-media filters have a strong ability to remove impurities in water. Common substances such as sediment, rust, suspended solids, colloids, organic substances, and some microorganisms can be effectively intercepted and adsorbed, significantly improving the clarity and purity of water quality and meeting the basic requirements for water quality in different industries and scenarios.

l Wide Range of Adaptability: Whether dealing with municipal water supply, industrial circulating water, domestic sewage, or groundwater of different sources and natures, multi-media filters can play a good filtering role. They can flexibly adjust parameters such as the types, particle sizes, and filling order of the filtering media according to the specific water quality conditions, thus adapting to complex and changeable water quality conditions with good versatility.

l Stable and Reliable Operation: Its structural design is relatively simple yet quite reasonable, and each component is of reliable quality. Under normal operating conditions, it is not prone to malfunctions and can operate stably for a long time, continuously providing a stable and up-to-standard water quality guarantee for the water use system, reducing problems such as water quality fluctuations caused by equipment failures, and the maintenance cost is also relatively low.

l Cost-Effectiveness Advantage: Most of the filtering media used in multi-media filters are easily accessible and relatively reasonably priced. Moreover, within a certain period of time, their filtration performance can be partially restored through simple maintenance means such as backwashing, extending the usage cycle. Overall, compared with some high-end and complex filtering equipment, the equipment procurement cost and operation cost are lower, bringing good cost-effectiveness to users.

l Simple and Easy Operation: The operation process of the equipment is not complicated. Usually, only basic operations such as controlling the inlet and outlet water and conducting regular backwashing are required. There is no need for professional technicians to conduct complicated debugging and maintenance. Ordinary staff can operate it after simple training, facilitating its promotion and use in various places.

APPLICATION FIELDS AND INDUSTRIES

l Industrial Field: In industrial industries such as chemical, steel, and power industries, a large amount of industrial water containing different impurities is generated during the production process. Multi-media filters can filter the circulating cooling water to remove impurities such as suspended particles and scale-forming substances in the water, prevent the cooling water pipelines from scaling and clogging, improve the cooling efficiency, and ensure the normal operation of production equipment. For some process water with relatively high water quality requirements, such as the dyeing water in the textile printing and dyeing industry, it can remove impurities and some substances affecting the dyeing effect in the water, ensuring the dyeing quality and improving the product quality.

l Municipal Water Supply Field: In the municipal water supply system, the source water often contains impurities such as sediment, algae, microorganisms, and some dissolved organic substances. As an important part of the pretreatment or advanced treatment process, multi-media filters can further purify the water quality, improve the quality of the water supply, ensure the safety and hygiene of residents' water use, enable residents to use clearer and odorless drinking water, and also help to reduce the maintenance cost of the water supply pipeline caused by the deposition of impurities and extend its service life.

l Sewage Treatment Field: For the treatment of domestic sewage and industrial wastewater, multi-media filters can first conduct preliminary filtration on the sewage to remove large suspended particles, some colloids, and some easily precipitated organic substances, etc., reducing the burden on subsequent treatment processes, improving the efficiency of the entire sewage treatment system, enabling the subsequent biochemical treatment, advanced treatment, and other processes of the sewage to proceed more smoothly, and finally achieving the goals of meeting the discharge standards or recycling the sewage, which has a positive significance for alleviating water resource shortages and reducing environmental pollution.

l Agricultural Irrigation Field: The quality of agricultural irrigation water directly affects the growth and yield of crops. If the water contains too many impurities, it is easy to clog the irrigation nozzles, resulting in uneven irrigation and even damage to the crops. Multi-media filters can filter various irrigation water sources such as surface water and groundwater, remove sediment, debris, and harmful microorganisms, etc., ensure the cleanliness of the irrigation water, enable the irrigation system to supply water to the crops evenly and stably, help to improve the yield and quality of the crops, and promote the sustainable development of agriculture.

SUMMARY

Multi-media filters, with their unique structural design, scientific working principle, and many excellent performance characteristics, have played an indispensable and important role in many fields such as industry, municipal, sewage treatment, and agricultural irrigation. They are like the versatile experts in water quality purification, quietly contributing to ensuring the cleanliness and efficient utilization of water resources, helping to stabilize the development of various industries and improve people's living quality. With the continuous progress of science and technology, it is believed that multi-media filters will continue to make breakthroughs in aspects such as improving filtration performance, optimizing the media materials, and expanding applications, further meeting the increasingly diverse water treatment needs of society and becoming one of the important supporting equipment for creating a high-quality water environment and promoting sustainable development.