Application of activated carbon filter series products in water purifier industry (2)
1. Coal-based and nutshell carbonized materials are crushed and screened to act as activated carbon products for sale in the market. The strength of such products will be slightly higher. The iodine value is generally between 200 ~ 300mg / g. Methylene blue has a very good decoloring power. Low, below 5ml / 0.5g, a little hard to detect. If the filter element is filled with such materials, the effect of adsorption treatment is very low.
2. Some small enterprises produce various types of fruit shells such as apricot shells, peach shells, walnut shells, jujube kernels, etc. through the soil method, and carbonize and activate them in a furnace at one time. After cooling, they are crushed and screened. The packaging is a finished product. The iodine value of the product is 500 ~ 600mg / g. If the iodine value is controlled, the iodine value will be higher. The decoloring power of methylene blue is about 5ml / 0.5g. Due to the limitation of production conditions, the moisture will be higher, about 15% Most of these products are used in industrial water treatment, and the price is generally around 5,000 yuan / ton. If used in household water purifiers, their physical and chemical indicators are relatively low.
3. Recycled carbon and virgin carbon are blended. If recycled carbon and virgin carbon of the same raw material and similar particle size specifications are blended in a certain proportion, the regenerated carbon must be decontaminated, decontaminated, and cleaned before being activated. Processing, such a mixed product, if there is no certain experience in the production of activated carbon, it is difficult to distinguish clearly. As activated carbon for water treatment, in some developed countries abroad, it will be repeatedly reused. The physical and chemical indicators of activated carbon after regeneration and activation are lower than the original carbon, and other indicators are not worse than the original carbon. Try to avoid the use of recycled activated carbon in water purifiers. Moreover, there are few domestic professional recycling plants and they are not standardized.
4. Good refined coal and high-quality natural coal-based crushed carbon. If products with similar specifications are blended into coconut shell activated carbon at a certain ratio, it is also difficult for ordinary users of activated carbon to distinguish. Most of the coconut shell carbonized material is imported from Southeast Asian countries, and its price is about 3,500 yuan / ton. The production should be different in terms of variety, specifications, and indicators. The activation yield is between 30% and 50%, and the yield of special products will be even lower. The crushing rate from activated materials to standard products is 80% ~ 85%, such as: Coconut shell water purification activated carbon has an iodine value of 1000mg / g, and requires methylene blue decolorization power of 150mg / g (10ml / 0.5g). Even for non-acid and water-washed carbon, the market price of the product should be about 13,000 yuan / ton. After water washing and pickling, the price will increase.
5. Some of the water purifier manufacturers use coal-based crushed carbon as the front filter. China has the world's recognized high-quality coal, among which there are excellent raw materials that can be used to produce coal-based activated carbon, most of which are distributed in Shanxi, Ningxia, Xinjiang, etc. If you choose to use it as a filter material for domestic water purifiers, because coal is a mineral raw material, metal oxides will be high, and even the possibility of heavy metals exceeding the standard, so the choice of raw materials must be careful, and raw materials should be dealt with in the early stages of production. Desulfurization, denitration, pickling and impurity removal are performed. Some of the coal-based granular activated carbon are natural crushed granules, and some are first pulverized, kneaded, shaped, carbonized, activated, and then crushed and sieved into granular activated carbon products of different sizes. The iodine value is more than 1000mg / g, and the decolorization power of methylene blue is more than 180mg / g (12ml / 0.5g), and some indexes are even higher. As long as the various indicators can be controlled within the relevant national standards, it is not uncommon to choose coal-based granular activated carbon as a pre-filter for domestic machines. Because of the surface functional groups of the carbon structure, chemical adsorption is more stable than structurally stable coconuts. Shell activated carbon is more advantageous.
Simple identification method for regeneration and recovery of activated carbon
Because activated carbon products have a wide range of applications, it is very dangerous and irresponsible to use activated carbon that has been used in pesticides, medicines and other chemical industries after it is regenerated and used in household water purifier filters. The harm it brings is extremely harmful. Large, we must resolutely put an end to such accidents. Regardless of the level of the indicators, from the appearance alone, because the raw materials and specifications of the waste carbon recovered by the activated carbon manufacturers are not exactly the same, it may be mixed with coconut shell charcoal, apricot shell charcoal, walnut shell charcoal, peach shell charcoal, or coal charcoal. After simple regeneration, the particle size of the product is not uniform, and the wall thickness of the particles will be significantly different. Among them, the apricot shell charcoal and walnut shell charcoal have thinner wall thicknesses, and the peach shell charcoal is thicker. However, if you carefully observe the local surface, there will be peach shell surfaces. With unique pits, it is difficult to identify small particles of 20 to 40 mesh carbon. In general, the degree of difference in particles is large. If the surface color of the particles is viewed, the surface of the product after high temperature regeneration has a dark color, the cross-section of the particles is not bright, and if you look at it closely, it will cause small cracks. If the angles and angles of the recycled carbon are not clear from the appearance and shape, it is mainly due to the friction between the particles during use. The industrial water treatment filter tank will often be flushed, recoiled and the particles will wear each other during the filtration process. This is especially noticeable when you lose sharp edges. Some recycled charcoal does not undergo high-temperature activation treatment, and is only used for simple acid washing, alkaline washing, and water washing. A small number of particles in the treated recycled charcoal have a dark yellow surface, and some have a small amount of quartz sand particles. All these phenomena can indicate that the above activated carbon products are not primary carbon, and at the same time, the ash content of some recycled carbon is too high. I have performed index analysis on the recycled carbon of some manufacturers. Most of the iodine values are 600mg / g, and some of the ash content is unexpected. Up to 15% or more, which is higher than ordinary coal-based carbon ash. I hope everyone will learn to identify during the use of activated carbon.
In short, as the activated carbon filter for household RO water purifiers, the index test must be performed on the selected activated carbon product, and the finished product filter must also be tested for performance parameters. Sometimes, although the activated carbon index meets the requirements selected by our company, However, during the performance test of the entire filter element, there are some project indicators that fail to meet the relevant national requirements. This will inevitably require the water purifier manufacturer to adjust the index of activated carbon, and repeat testing until the performance parameters of the filter element reach the standard.
For RO household water purifiers with buckets, the main function of the rear activated carbon filter is to improve the water outlet and inhibit the growth of bacteria. Activated carbon itself must be of high purity. The first choice is coconut shell acid-washed charcoal, and some consider the use of silver-loaded coconut shell charcoal for bacteriostasis. Regarding the effluent of household RO water purifiers, because it uses a first-stage RO reverse osmosis process, the TDS value of the pure water produced is about 10mg / l, and a few due to the difference in RO membrane will also be about 5mg / l The pH value is between 6.0 and 6.5. There is still a certain difference in taste between this type of water and some bottled water on the market. First of all, the pure water of bottled water generally adopts the second-stage reverse osmosis production process, and the TDS value of the effluent is almost undetectable. Finally, the quenching and tempering treatment is performed to adjust the pH value to about 8, so that the water will be sweet and refreshing. But taste problems also vary from person to person. )
Next: Application of activated carbon filter series products in water purifier industry (1)
Related industry knowledge
- Which one is better, namely, a hot line pipe machine and a heat pipe machine?
- How much do you know about the water purifier solenoid valve?
- How to install the water purifier connector?
- What are the common water purifier accessories? What is the role of accessories?
- How to replace the water purifier filter and precautions?
- The role and replacement cycle of the small T33 filter element!
- Korean water purifier quick connection filter requirements?
- How to judge the pros and cons of PE pipe for water purifier?
- Water purifier filter element of water purifier principle (1)
- How to replace the small T33 filter element?
- Introduction of water purifier accessories and common units of measurement (on)
- Introduction of water purifier accessories and common units of measurement (below)