1, manganese sand filter material
Manganese sand filter material is made of domestic natural manganese sand with excellent quality, dense particles, high mechanical strength, strong chemical activity, not easy to be broken and insoluble in water, and is made by washing, polishing, impurity removal, drying, magnetic separation, screening and dust removal. Then the treated manganese sand is mixed according to a certain gradation. It has the most ideal gradation ratio of water treatment filter material, which makes it have the largest specific surface area per unit volume, the strongest pollution interception ability, the largest oxidation catalysis and the smallest backwashing loss rate.
The appearance of manganese sand filter material is rough and brown or light gray, and it is often used in iron and manganese removal filtering devices for drinking water, with good filtering effect. (Note: MnO _ 2 ≥ 35% can remove both iron and manganese, and MnO _ 2 ≤ 30% can only be used to remove iron from groundwater) Manganese sand filter material is mainly used to reduce the total content of iron and manganese in water. According to the hygienic standard of drinking water in China, its iron content is ≤0.3㎎/L, and its manganese content is ≤ 0.1㎎/L. 。
Working principle of manganese sand filter material
Iron exists in underground (well) water in the form of Fe2+, and its water has different colors and smells, which pollutes ion exchange resin and reduces exchange capacity. After a long time, mill scale will be produced, which will affect heat transfer and corrode equipment. The reaction between MnO2 _ 2 and Fe2+ in manganese sand makes Fe2+ change into Fe3+ and generate? Fe(OH)3 precipitates, so that the purpose of removal and purification can be achieved by using the backwashing function of manganese sand filter.
The natural manganese sand filter material used to remove iron and manganese from groundwater should be mainly manganese oxide. Natural manganese sand filter material with manganese content (calculated by MnO2 _ 2, the same below) not less than 35% can be used for both iron removal and manganese removal in groundwater. Natural manganese sand filter material with manganese content of 20% ~ 30% is only suitable for iron removal in groundwater; Manganese ore with less than 20% manganese content is not suitable.
2. Medical stone
Medical stone is a kind of compound mineral or medicinal stone which is non-toxic and harmless to organisms and has certain biological activity. Medical stone contains aluminosilicate (feldspar), which has the ability to adsorb pigments and bacteria. If medical stone is ground into powder, the dissolution and adsorption of ions will be enhanced. Treating water with medical stone makes it become water with many+and-electric groups. Medical stone can adsorb ions in water. After passing through water, medical stone can dissolve out macro elements useful to human body and organism, and also can dissolve out amino acids necessary for human body in aqueous solution.
The role of wheat flaky
(1) strong adsorption capacity
The so-called adsorption means that all solids with porosity and huge surface area are dissolved and undergo chemical and physical reactions. Medical stone is porous and has strong adsorption capacity, because its main components are silica and alumina, which is easy to understand from this point of view. ? That is to say, because of its porosity and large surface area, and because feldspar is partially weathered into kaolin, it has always maintained strong adsorption and exchange.
(2) Dissolve out minerals
It can improve water quality, inhibit bacteria and adsorb organic matter by containing proper amount of minerals in beverage water. ? Therefore, when medical stone is put into water, free chlorine, impurities, organic matter and miscellaneous bacteria in the water can be adsorbed and decomposed, and minerals can be supplemented into the water. Therefore, water can be prevented from being corroded, and high quality water can be obtained. Static state: the activity of bacteria is inhibited and is in a static state. The so-called bacteriostasis is to prevent bacteria from multiplying.
(3) Adjust the water quality
As far as minerals such as iron, magnesium and fluorine are concerned, they are dissolved when they do not exist in water, on the contrary, they are adsorbed when they exist in water too much. ? This effect is related to the pH value. Except for water which is too acidic and alkaline, medical stone is put into purified water, and in most cases (alkaline) it is put into water, and in a few cases (acidic) it can make water close to neutrality. Moreover, after circulating water several times in the medical stone layer, the PH value can be adjusted even if the water volume is large.
Note: It can be clearly seen from the above table that it can adsorb a little more Mg (that is, it can dissolve less), but it also shows the same phenomenon for iron and manganese. From this fact, we can understand the buffering effect of medical stone in water.
(4) The purifying effect of medical stone on water
Medical stone is neutral alkaline semi-igneous rock, close to volcanic rock.
Characteristics of medical stone
A. permeable
B. Strong adsorption and water purification functions
C. Natural minerals contained in medical stone are easily released, and oxygen is released from numerous small holes in medical stone. Purify water by absorbing bleaching powder and other toxic substances. Minerals such as calcium, iron and sodium emitted by medical stone can improve drinking water.
3. Activated carbon
Activated carbon, also known as activated carbon black, is black powder or granular amorphous carbon. The main components of activated carbon are carbon, oxygen, hydrogen and other elements. Structurally, activated carbon is a kind of porous carbon with low bulk density and large specific surface area. Because microcrystalline carbon is irregularly arranged and there are pores between cross connections, carbon structure defects will occur during activation.
Main uses of activated carbon:
Decolorizing and filtering to decolorize the colored liquid; Absorb all kinds of gases and vapors; Used for chromatographic analysis; Measuring reducing agents of methanol, tin and silicon; Particles can be used as carriers of catalysts.
Classification of activated carbon:
Due to the different sources of raw materials, manufacturing methods, appearance and shape, and application occasions, there are many kinds of activated carbon, so far there is no accurate statistical data, and there are about thousands of varieties.
According to appearance and shape:
1.？ powdered activated carbon
2.？ granular activated carbon
3.？ Unshaped granular activated carbon
4.？ Cylindrical activated carbon
5.？ Spherical activated carbon
6.？ Other shapes of activated carbon
4. Quartz sand
Quartz sand is a timely particle made of quartz stone. It is a nonmetallic mineral and a silicate mineral, which is hard, wear-resistant and chemically stable. Its main mineral component is silicon dioxide. The color of quartz sand is milky white or colorless and translucent, with hardness of 7, high brittleness and conchoidal fracture.
Quartz sand is an important industrial mineral raw material and does not belong to dangerous chemicals. Widely used in glass, casting, ceramics and refractories, smelting ferrosilicon, metallurgical flux, metallurgy, construction, chemical industry, plastics, rubber and so on. High purity quartz sand abrasives and other industries. ? It can be transported by car, train and water. Industrial production is generally packed in 50 kg or 25 kg, and exported in tons of bags. Common specifications: 0.5-1.0mm0.6-1.2mm1-2mm 2-4mm 4-8mm 8-16mm16-32mm. (Millimeter is in millimeters).
Ordinary quartz sand is generally a kind of water treatment filter material made of natural timely ore through crushing, washing, drying and secondary screening. At present, it is the most widely used and largest water purification material in the water treatment industry. The filter material has the characteristics of no impurities, no edges and corners, high density, high mechanical strength and long life of sewage interception capacity, and is an ideal material for chemical water treatment. It is suitable for single-layer and double-layer filter tanks, filters and ion exchangers, and all indexes meet the standard (CJ/T43-2005). The granularity range is 5-220 meshes, and it can be produced according to user's requirements. Main uses: metallurgy, ink silicon carbide, glass and glass products, enamel, cast steel, water filtration, sodium silicate, chemical industry, spraying noise and other industries.
Application of quartz sand as filter material for water treatment
Because the particle size of quartz sand in the three-layer filter bed is smaller than that in the double-layer filter bed, and there is a finer layer of heavy anthracite filter material under the quartz sand layer, the water quality of the filtered water in the three-layer filter bed is better than that in the double-layer filter bed, even at a higher filtration rate, under the same other conditions. When using quartz sand, try to cooperate.
5. Activated zeolite
Activated zeolite is made by activating natural zeolite through various special processes, which is characterized by stronger adsorption and ion exchange performance than natural zeolite.
It can not only remove turbidity, chromaticity and peculiar smell in water, but also adsorb and exchange harmful heavy metals in water, which is also beneficial to remove various trace pollutants in water. The water leaching solution does not contain toxic substances harmful to human body, and the effect of removing iron and fluorine in water is more obvious. Therefore, activated zeolite is an ideal new filter material for industrial water supply, wastewater treatment and tap water filtration. It has large specific surface area, strong adsorption capacity and ion exchange capacity, has adsorption and catalytic degradation capacity for organic pollutants in sewage, has strong adsorption and solidification capacity for pollutants such as heavy metals, has good chemical stability in sewage, and does not decompose, deteriorate or pollute water. It can effectively remove COD, BOD5, NH3-N, TP, suspended solids and other substances in water, and can effectively remove heavy metals (cadmium, chromium, mercury, lead, arsenic, etc. ) and radioactive substances in water, and has the functions of decolorization, deodorization and deodorization.