Deep underground water intake seems to have "clean" water quality, but in fact there are hidden sediment particles, colloidal suspended solids, ferromanganese oxides and even various organic odor factors. If it is not fully pretreated and sent directly to the reverse osmosis host, membrane surface fouling, flux attenuation, and desalination efficiency will be almost unavoidable, and the life of the equipment will be greatly reduced.The pre-filtration system can be called the throat fortress of the entire water purification production line-the selection is lost by a hair's breadth, and the operating effect is thousands of miles away.Based on the accumulation of actual combat construction of hundreds of deep wells, Xi'an DIEN Water treatment disassembles the selection logic of quartz sand filters, activated carbon filters, and precision filters layer by layer, providing a landing technical reference for deep well water purification scenarios such as industrial water production, factory supply, and township centralized drinking water.
Precision filter
Compared with tap water in municipal pipe networks, the composition of deep well water is more primitive and rough. After standing still, fine sand particles and metal oxides that are invisible to the naked eye often precipitate. A coarse filter alone cannot hold the threshold of reverse osmosis water inlet.The common practice in the industry is to construct a three-stage gradient interception: the first stage quartz sand coarse filtration intercepts large particles of suspended solids and silt, the second stage activated carbon deeply absorbs heterochromatic odors and residual oxidants, and the third stage precision filter element is the ultimate barrier. The three levels are interlocking, so that the turbidity of the water inlet and the pollution load can be pressed to a safe range that the reverse osmosis membrane can withstand.
The mission of the three-level filter
"Coarse screening" is undertaken by quartz sand tanks to block sand particles, flocs, and colloidal clumps in well water, while reducing the turbidity of raw water to prevent hard particles from scratching the membrane surface; activated carbon tanks specialize in "adsorption and purification" to deal with rust smell, earthy smell, residual chlorine residues and various organic molecules, and build an antioxidant barrier for membrane elements from the chemical level; precision filters are the last insurance, capturing the fine debris and filter powder that escaped in the first two stages, ensuring that every drop of water entering the high-pressure pump is clean and up to standard.
The core consideration of precise selection
The diameter of the quartz sand tank and the thickness of the filter layer must match the peak wellhead effluent volume and turbidity. For high-content manhole sources, it is recommended to use a thickened tank body with a double-layer sand material, and an automatic backwash valve set is standard to prevent the filter layer from compacting the bed; the activated carbon section is the first to promote coconut shell or fruit shell-based high iodine carbon material, with a large specific surface area and high adsorption capacity. It is more emboldened to face the complex organic matter in groundwater; precision filters routinely lock the accuracy of 5 micron filter elements, if the concentration of impurities in raw water exceeds the norm, multiple stages of filter elements with different pore sizes can be connected in series to form a ladder to trap the wind. The risk is minimized.
Record of Deep Well water Treatment in Lam Tin Factory Area
A manufacturing plant in Lantian, Xi'an, uses deep groundwater as a production source. The water quality is muddy all year round and mixed with trace amounts of fine sand and ferromanganese ions. The owner plans to install 8 tons/hour reverse osmosis pure water equipment.At first, a set of simple pre-equipment was pieced together for the provincial budget. The filter tank was too small and the sand layer was thin. As a result, the inlet pressure of the high-pressure pump rose sharply within half a month of starting up. The reverse osmosis membrane group frequently warned of blockage, and the water production fell precipitously. , The production line was forced to stop water intermittently.
After DIEN's technical team rushed to the site to take water for testing and compare the water quality from well to well, they overturned the original plan and redesigned the three-stage front: the front end was replaced with a large-flow quartz sand tank and the frequency of backwashing was encrypted, the middle section was filled with high iodine value husk charcoal, and the end was equipped with stainless steel precision filtration with multi-stage filter elements.After the renovation ended, the turbidity of the water inlet and the SDI index both fell into the allowable range of reverse osmosis. The entire unit has been running continuously for twelve months without a membrane blockage alarm, and the replacement cycle of consumables has been nearly doubled compared to before.
DIEN well water filtration equipment is directly supplied by the source manufacturer, eliminating the need for middlemen to increase prices." "Pre-selection and supporting plans for the whole machine can be issued one-to-one for different well depths, water volumes, and uses, from equipment manufacturing, on-site installation to long-term maintenance and maintenance, so that every step of deep well water from "Raw" to "Pure" is controllable and predictable."
