What is the function of the filter membrane of manganese sand filter media

Natural manganese sand iron removal is a contact catalytic iron removal process, which is suitable for iron removal with an iron content of less than 20mg l in groundwater. The ** manganese contained in natural manganese sand can oxidize the divalent iron in the water into trivalent iron, and at the same time form an "active filter membrane" with catalytic effect on the surface, which further improves the iron removal effect.

After the molten iron is aerated and filtered only once by natural manganese sand, it can complete the whole iron removal process, which is often used in drinking water iron removal, manganese removal filtration device, groundwater iron and manganese removal to purify water quality.

When water containing iron and manganese passes through the surface of the filter media for a long time, iron and manganese filter membranes will be formed on the surface of the filter media. Because the adsorption capacity of the filter material is stronger for iron and manganese, the modified filter material can shorten the formation time of the ferrous and manganese filter membranes, and the iron filter membranes formed under the natural conditions of the manganese sand filter material often take several weeks, and the time to form the manganese filter membranes is longer. The formed iron and manganese filter membranes generally have a catalytic effect on the removal of iron and manganese, which is what we call "active filter membranes".

1. Manganese sand filter process: aeration, contact oxidation, adsorption filtration, backwashing.

2 Running the process.

Aeration. According to the water quality, the deep well water residual pressure jet aeration or compressed air aeration is adopted, and the pipeline is mixed with dissolved oxygen, which is stable and reliable.

On the one hand, the aeration method is to increase the dissolved oxygen in the water; The second is to remove CO2 to increase the pH value of the water, so that the divalent iron is oxidized to trivalent iron precipitate, and then filtered.

Contact oxidation. The filter material is made of natural manganese sand filter media, which has catalytic and filtration double-layer effects.

The main component of natural manganese sand is manganese dioxide (mnO2), which is a good catalyst for the oxidation of Fe2+ to Fe3.

When the pH value of iron-containing groundwater is reached, Fe3 can be oxidized to Fe3 in contact with natural manganese sand, and the reaction is as follows: The generated Fe3+ is immediately hydrolyzed into flocculent iron hydroxide precipitate: Fe3++3OH-=Fe(OH)3

Adsorption filtration. a.The floc formed by Fe3 (Fe(OH)3 precipitate was removed after the manganese sand filter layer;

b.Most of the unoxidized Fe2+ catalyzes oxidation and oxidized ion exchange in order to remove iron.

In addition to relying on its own catalytic effect, the iron removal mechanism of manganese sand also gradually forms a layer of iron filter membrane on the surface of the manganese sand filter material as an active filter membrane during filtration, which can play a catalytic role. The newly formed iron oxide is used as an active membrane substance and participates in the new catalytic iron removal process, so the iron removal process of the active filter membrane is an automatic catalytic process.

The principle of manganese removal is the same as that of ferric iron.

Manganese sand filter backwash.

The manganese sand filter system can be controlled manually and automatically. It is required to regularly backwash the manganese sand to remove impurities such as suspended solids that may be intercepted, and at the same time loosen the manganese sand and cushion. Since the filter is equipped with a backwashing device, there is no need to be equipped with a backwashing water pump.

Under the action of catalyst (such as manganese sand), the dissolved divalent iron or divalent manganese is oxidized into insoluble trivalent iron or tetravalent manganese compounds, and then filtered to achieve the purpose of removing iron and manganese.

4fe2++o2+10h2o 4fe(oh)3+8h+

2mn2++o2+2h2o 2mno2+4h+

The main function of the manganese sand filter is to reduce the iron and manganese content in the water quality, which is generally used in the underground treatment of well water and high iron content;

The process is mainly through two steps: contact oxidation, adsorption and filtration to achieve the purpose of removing iron Meng;

1.Contact oxidation: Using high-quality manganese sand as raw material, manganese sand filter media has the role of catalytic and filtration double layer. The main component of natural manganese sand is manganese dioxide, which is a catalyst for the oxidation of ferric iron to ferric iron.

2.Adsorption filtration.

The ferric iron removed after passing through the manganese sand filter layer will form flocs;

The manganese sand filter can exchange most of the incompletely oxidized ferric iron with the oxidized ions after catalytic oxidation to facilitate iron removal.

Manganese sand contains mnO2, mnO2 is an oxidation catalyst, ** manganese can oxidize the divalent iron in the water into ferric iron, and at the same time form a catalytic "active filter membrane" on the surface, and the active filter membrane formed is attached to the surface of the manganese sand to further participate in catalytic oxidation, so the pre-treatment effect is better if the manganese sand is used as the filter material, the effluent quality is good, and the filter material has a short maturity cycle.

Most of the quartz sand filter material is produced from sea sand or river sand, and some natural quartz ore is used, which is crushed, washed, screened, pickled, dried, and screened twice. Due to the low cost of quartz sand, many water treatment projects only require simple treatment of water quality (impurities such as sediment and other impurities in the water) in order to save costs, or the water quality is not tested after treatment, so quartz sand is the most widely used and largest water purification material.

In the case of mixed use of quartz sand and manganese sand, the quartz sand must be at the bottom layer, and the filter layer must be manganese sand.

Difference: Manganese sand is the removal of iron and manganese from groundwater.

Quartz sand is a supporting layer that removes impurities in the water.

Similarities: Both manganese sand and quartz sand media are placed in water.

1. Both can be removed from sediment, particulate suspended solids, algae and solid impurities in the water;

2. Quartz sand is white crystalline, large and small according to the number of meshes; Manganese sand is granular reddish-brown;

3. Quartz sand mainly removes the excess iron in the water (the iron exceeds the standard, the water quality is yellow, and the water drips to the ground for a long time to form yellow imprints, or leaves obvious yellow substances on the pool wall); Manganese sand mainly removes excess manganese in the water (manganese exceeds the standard, the water quality is reddish-brown, and the water drips to the ground for a long time to form reddish-brown imprints, or leaves obvious reddish-brown substances on the wall of the pool);

4. The market of manganese sand is much more expensive than quartz sand;

5. The use of quartz sand is relatively wide, and the use of manganese sand is relatively rare, which is often used in well water treatment;

6. In water treatment, we often call it: quartz sand filter, manganese sand filter;

7. According to the situation that the water quality of iron and manganese exceeds the standard, quartz sand and manganese sand can be used at the same time or separately;

Manganese sand filter material: because the manganese sand filter material contains mNO2, mno2 is a catalyst, ** manganese can oxidize the divalent iron in the water into ferric iron, and at the same time form a catalytic "active filter membrane" on the surface, and the active filter membrane formed is attached to the surface of the manganese sand filter material to further participate in catalytic oxidation, so the pre-treatment effect is better if the manganese sand is used as the filter material, the effluent quality is good, and the filter material has a short maturity cycle. After treatment, it meets the national drinking water sanitation standard "GB5749-2006", iron, manganese.

Quartz sand filter material: quartz sand filter material is a kind of water treatment filter material made of natural quartz ore, crushed, washed, screened, pickled, dried, and screened twice, widely used and large amount of water purification materials, no impurities, compressive and wear-resistant, high mechanical strength, stable chemical properties, strong dirt interception ability, high efficiency, long service life, suitable for single-layer and double-layer filter pools, filters and ion exchangers, and all indicators have reached the (CJ T43-2005) standard. However, when it is used to remove iron and manganese, the maturity cycle of the filter material is long before use, and the effluent quality in the early stage is not good.

After the filter material is mature, the effluent quality reaches the national drinking water hygiene standard "GB5749-2006" iron and manganese.

The filter material is manganese sand (except iron and manganese), which is called manganese sand filter.

Mechanical filters and multi-media filters are pre-treatment equipment used in water purification equipment, and their main role is to remove suspended substances and solid particles in water. Its materials are made of a variety of materials, such as: PE, steel lining, steel spraying, steel epoxy anticorrosion, stainless steel, etc.

According to the different filter media media, the use and function are also different, generally quartz sand old powder, activated carbon, manganese sand, anthracite, etc. Quartz sand is also known as quartz sand filter for the filter material in the core, anthracite is used for the filter material, and manganese sand (except iron and manganese) is used for the filter material, and activated carbon is used for the filter material. It can also be combined.

The main function of the manganese sand filter is to remove suspended solids, mechanical impurities, organic matter, reduce the turbidity of water, adsorption, remove pigments, residual chlorine colloids and iron ions in the water, etc., the machine can be selected according to the size of the filtration volume, and the use and operation are very simple.

Summary. Generally speaking, 20-40 mesh is used for coarse filtration and 40-60 mesh for fine filtration.

Generally speaking, 20-40 mesh is used for coarse ridge filtration and 40-60 mesh for fine filtration. Searching.

Excuse me, but please go into more detail?

Manganese sand filter is a commonly used water treatment equipment, which can effectively remove heavy metal ions such as iron, manganese, lead, nickel and other heavy metal ions in the water, as well as substances such as color, odor and turbidity, and improve the reliability and safety of water quality in the pretreatment process of sanitary cleaning water. Manganese sand filters use a filter medium, manganese sand, which is usually a particle size or, or, traditionally, a natural ore, and sometimes even processed from industrial by-products or discarded slag. In practical application, the filtration speed of the manganese sand filter is related to the particle size of the filter medium, specifically, the particle size effect is usually better, which can improve the filtration measurement and filtration effect of the filter.

At the same time, factors such as the selection of the filter medium and the operating conditions also directly affect the working efficiency and long-term service life of the manganese sand filter, so it is necessary to pay attention to the maintenance and maintenance of the filter in the process of use and maintenance, and replace and clean the manganese sand filter in time.

The process of removing iron from water by manganese sand filter media is composed of three parts: aeration, oxidation reaction and filtration. The pH value of water has a great influence on the oxidation reaction rate of ferric, and the pH can be increased to above to remove part of the CO2 by aeration and oxygenation, which can obtain a good oxidation reaction of ferric iron and the flocculation and precipitation of ferric, and then remove it by filtration.

However, often the water generally contains a small amount of dissolved silicic acid, so that the SiO(OH)3 ions in the water are strongly adsorbed on the surface of the hydroxide colloidal of ferric iron, so that the hydroxide colloidal flocculation of ferric iron is difficult, resulting in penetrating the filter layer and affecting the effect of iron removal.

Therefore, contact oxidation is widely used to remove iron. In this method, after the water is aerated and oxygenated, the iron is removed and oxidized by the filter media adsorbent, and an iron filter membrane with catalytic activity is gradually generated on the surface of the filter material. The ferric active membrane further plays a role in removing iron.

Contact oxidation of iron removes the catalytic effect of the iron active filter membrane, which greatly accelerates the oxidation rate of ferric and makes the manganese sand filter material remove iron from water faster.

1. Large specific surface area and high biological adhesion: the third-generation active biological filter material has high porosity, large specific surface area and stable chemical properties, which is especially suitable as a medium for microbial reproduction. Compared with quartz sand, the specific surface area is more than 10 times that of quartz sand of the same volume, and the porosity is more than 5 times that of quartz sand, which is suitable for microbial multiplication and biomass is very large.

2. Deep phosphorus removal and high ammonia nitrogen removal rate: after the third-generation active biological filter material combined with microbial nitrification reaction, the ammonia nitrogen removal rate reaches 60%, and reaches 99% in 15 days and is relatively stable; And it can remove phosphorus in depth, and the removal rate after 12 hours is up. It can adsorb harmful elements and bacteria in the water body, mineralize the water quality, and is the preferred filter material for active biodegradation and decomposition to reduce harmful substances.

3. High strength hydraulic shear resistance and low damage rate: The third generation of active biological filter material has been tested by authoritative testing institutions, and the cylinder compression strength is 10-15MPa, which is much higher than that of other similar products, and has been proved to be resistant to hydraulic shear of different strengths, with low damage rate, greatly improved service life, and reduced the comprehensive cost of sewage treatment.

4. No secondary pollution can effectively reduce the total amount of sludge: the third-generation active biological filter material can continue to reproduce a large number of microorganisms in the micropores, which is not easy to lose, and can effectively reduce sludge discharge. It has strong adaptability to changes in water quality and quantity, and is not easy to swell sludge.

Working principle: Generally speaking, in many cases, iron has been in the groundwater in the state of Fe2+, and this drinking water has a different color and odor, of course, pollution will also reduce the exchange capacity through ion exchange resin, so the mnO2 in the manganese sand and Fe2+ undergo redox reaction, so that Fe2+ becomes Fe3+ and is generated.

Fe(OH)3 precipitation, so that all kinds of heavy metal substances in the water can be purified.

The filtration effect of manganese sand filter is mainly reflected in:

1. The activated carbon adsorption filter cylinder body adopts the design of hydraulic simulation long diameter, and adopts activated carbon with reasonable particle size and specific surface area greater than 1000 g, so that it has both upper filtration and lower adsorption functions, which greatly improves the purification degree of produced water and the service life of carbon. 2 Residual chlorine content of water treated by activated carbon adsorption filter: .

3. Outstanding performance on odor, organic matter, colloid, iron and residual chlorine in the water body;

4. It also has a good effect on reducing the turbidity and color of the water body, purifying the water quality, and reducing the pollution of the follow-up system (reverse osmosis, ultrafiltration, ion exchanger).