The dihydroxylation process produces activated alumina from aluminum hydroxide to give a porous solid object. These are widely used as desiccants and filters for water purification.
Natural drinking water contains many minerals like fluoride, arsenic, selenium, etc. These minerals are the reasons for considering water as a precious part of our diet and good health. But if any of these minerals exceed the permitted limit, it can lead to severe health issues. Thus, the purification of water is highly recommended. In this article, we will see the role of activated alumina in water treatment.
Water purification by activated alumina
The principle works in removing arsenic content by the activated alumina bed. Known as adsorption. The arsenic content in water may rise beyond the permissible boundaries due to deposits from industries, agricultural processes, or even through natural means. When in huge quantities, this will cause many health issues.
The water to be treated is allowed to pass through a bed of activated alumina under high pressure. More than one filter bed can be used back to back for improved results. The arsenic content gets adsorbed by activated alumina beds when passed continuously for a pre-determined time, and the processed water is collected for further use.
The quality of the activated alumina arsenic removal process depends on certain water factors under treatment, such as pH, water quality, presence of other impurities, and compound form of arsenic. Arsenic can be present in two forms, As (V) (arsenate) and As (III) (arsenite). It is recommended to process the water before it is passed through an activated alumina bed and oxidize the As (III) to As (V) because the alumina filter handles As (V) more efficiently. Also, the pH range of water is to be maintained within 5.0 to 6.0 for smooth and maximum adsorption.
One main benefit of using activated alumina for water treatment is that it is resistant to liquid water. This means it will not shrink, swell or get diluted when immersed in water for a long time. The activated alumina beds can be regenerated and reused. The high surface area and high adsorption capacity place the activated alumina as one of the best methods for water purification.
Being one of the prime Activated alumina balls manufacturers, Sorbead India offers high-quality products at affordable prices around the globe. Contact us for more information.
Desiccants are said to those substances which can absorb moisture and odor. Having excellent absorption capacity, it can maintain the product's originality by preventing any microbial activities. Although moisture is present everywhere, its presence is unnecessary places can be quite disastrous. Most of the desiccants are available in granular or powdered form. The reason that these desiccants are in this form is that in this way, it gets more surface area for absorption. This form allows the desiccant to absorb more moisture content from the atmosphere. However, these desiccants cannot be used loosely, so they are used in packets. Now the size of the packets depends on the requirement. You must have seen small packets of desiccants in leather jackets and plastic containers. While at the same time, huge bags of desiccants are also used while transporting that cargo on a ship.
There is various type of air drying desiccants available in the market. The most popular and widely used desiccant is silica gel. It also comes in three variants that are orange, white, and blue. Among the three, orange and blue are the color-changing gel. After absorbing moisture, the granules change their color, indicating that the desiccant granule is contaminated and needs to be replaced. Another reason which makes it more popular is that once it is fully contaminated, it can be reused again by heating it over 300oC. The other type of desiccant is molecular sieves. Its properties are quite similar to that of silica gel. The advantage of using it over other desiccants is that its absorption speed is more, and it has more resistance to contamination.
Apart from this, there are other desiccates like activated carbon and clay. So desiccants can either be used alone or in combination with the other ones. In this way, we can get rid of two factors at a time that is moisture and odor. For example, silica gel and activated carbon can be used where silica gel can absorb moisture, and activated carbon can absorb odor. Clay is said to be a natural desiccant. It is said to be the most efficient and cost-effective desiccant. One drawback of this desiccant is that it needs to be replaced immediately after it is contaminated.
Sorbead India is the manufacturer and supplier of alumina balls desiccant for the industrial air-drying process. Air drying desiccants are used for compressed air drying, heated & heatless air drying, etc.
Activated alumina balls are not only a bad conductor of electricity but have a good capacity to resist heat for a long duration. Its rigidity is that the alumina molecules are very close to each other; thus, its density is quite high. And this is the reason the most common shape given to alumina is in the form of balls. The external surface of the alumina ball is quoted with such a solution so that it can easily reflect sunlight avoiding any reaction. Alumina balls manufacturer designs the surface of the balls smooth, which makes it idle to use in various grinding processes. Apart from this, it is also used for filtration purposes. It is also used to abstract minerals from ores by making them highly porous. These white coloured balls are usually combined with the latest technology to ensure their flawlessness.
Being the fourth utility of a production facility (the other three being electricity, water and gas) compressed air is a very important resource that should be carefully treated in any manufacturing plant. It should be carefully examined in a periodical manner. The moisture present in the air should be removed and also the contaminants should be eliminated. This will result in the efficient working of the whole system. Improved performance and reduced operational costs are two major perks of having efficient air and gas drying systems.
Air drying is one of the most significant processes carried out in most large industries. In this technique, the moisture from coatings and surfaces are removed by using hot, dry or forced air. Moisture present in the air can affect colour, coatings etc., and also lead to damage and corrosion. But air-drying is employed to prevent all those problems.
Significance of compressed air and gas drying
Regular atmospheric air and compressed air all contain some amount of water vapour. This water vapour will cause problems in future because of an increase in water concentration in the system. Therefore, to prevent problems in the future, wet air must be controlled. Drying equipment can be used for the same purpose.
There is moisture present in the irregular atmospheric air that will have moisture content. When the air or gas crosses the saturation point, this vapour will condense and reach the liquid state. This process happens at a certain temperature and this temperature is known as the dew point.
When the compressed air employed in the manufacturing plant contains moisture, it will damage various valves, pneumatic air systems, air motors, different passages etc. They will cause damages, wear and tear, impact lubrication, corrosion, causes the valves and passages to be plugged and clogged and also affects the overall functioning of the system. Further, the moisture harms the adherence, colour and finish of paint etc. Hence, they- lead to malfunctioning, false readings in the instruments, faulty operations, and even cause the total system to shut down.
Compressed air and gas drying becomes necessary to obtain perfectly finished products, for the smooth flow of uninterrupted production, improved performance of the whole system and reduced operating costs.
Air is required in most manufacturing facilities or plants. Most of these plants need dry and clean compressed air for the smooth flow of their operations. Water molecules, dirt or any other contaminants will be deposited inside the pieces of equipment that can even lead to a drop in the pressure of the system. This drop indicates low efficiency in the overall performance of the system.
In these pieces of equipment, dry and moisture-free air is needed, as even a little amount of moisture or water vapour can produce significant issues. This may plug the air passages and block them. Further, they can lead to instrument damage. Pneumatic thermostats that are used in the air conditioning and heating cycles of buildings is another instrument that needs dry air.
These types of instruments used in sewage treatment units, manufacturing plants, textile manufacturing units, petrochemical plants are all examples of facilities that need dry air for their smooth flow and efficient operation.
The slime or sludge that is formed by the dirt and contaminants or oil in the air causes blockages in valves and acts as drags in the cylinders. This causes damages and results in frequent maintenance. There will be a lag in operations, this slowdown of operations will gradually lead to the shutting down of the system. The efficiency will be very low and there will be an increase in costs too.
These are the main reasons why compressed air and gas need drying. Air-gas drying can be achieved through various techniques. Use of air dryers is one popular technique used nowadays and among them, use of desiccant air dryers is the one with most demand as it employs a heatless method.
The regenerative desiccant air dryers use a desiccant. Activated alumina balls are used mainly in these systems nowadays. These desiccants absorb all moisture content from the air. They have the maximum water adsorption capacity than other adsorbents including silica gel and molecular sieves. Activated alumina balls are exceptional adsorbents of water vapour and moisture. They are highly porous non-toxic substances with high surface area. Sorbead India is one of the most reliable suppliers of high-quality activated alumina balls in India. They provide activated alumina balls of different sizes and types for different types of air dryers.
Air compression involves making the molecules come closer, and thus force them to fit into a smaller space. This process involves an increase in temperature and is known as the heat of compression. In any air compressor or compression air dryer, this same process is involved and thus results in a lot of heat emission. It is dangerous to leave the heat emitted unattended because it can easily overheat the compressor and can result in an explosion.
Activated alumina balls as the drying medium in a heatless compression air dryer is the best choice to avoid this overheating of the compressor. Let’s look at the heatless compressed air dryer.
Heatless compressed Air dryer
By using activated alumina for the air dryers, we can devise the heatless compressed air desiccant dryer. A dual-chambered arrangement filled with desiccants is aligned to adsorb the water molecules from compressed air. The final output would be hot dry air. The heat of adsorption is retained by the desiccant balls and is prevented from being accumulated at the chamber outlet. This heat is further used for regeneration in the subsequent cycle to nullify the heat accumulation. Effective heat retention, a dense medium of high volumetric heat capacity can be introduced at the end of the adsorption chamber.
But this process consumes a portion of the dry air output from a compressed air dryer. The amount of this consumption can be reduced by the below methods:
There are majorly two types of desiccant air dryers which are pressure swing compressed air dryers and externally heated compressed air dryers. The pressure swing regenerative dryers and the high-pressure swing dryers are efficient in reducing the accumulated heat from the entire system. These regenerative dryers make use of the adsorption heat energy retention concept to maintain the heat of compression within limits.
Air drying desiccant balls
The best air dryer desiccant beads in use are activated alumina. It is very important to keep compressed air free of moisture because moist compressed air can cause various damages to the compressor. The valves, motors, and insulations can be affected, the final product can be altered, rusting and corrosion, damage to pipes, total blockage of the system are some examples of the adverse effects of moisture content in the compressed air. So, it is very important to maintain the PDP of a compressor system as low as -40 degrees centigrade.
Regeneration dryers that involve activated alumina balls as adsorbents have doubtlessly proven to be highly efficient and effective. Activated alumina uses the concept of adsorption to trap water molecules that come in contact with the desiccant surface. With no chemical or thermal reactions involved, the use of desiccant air dryer beads is of low operating and maintenance cost. Activated alumina balls are non-toxic, colorless, tasteless, and insoluble, and have high thermal and mechanical strength.
The ease of regeneration of activated alumina balls is a highly recommendable feature. Activated alumina balls in the desorption chamber of the dryer are triggered to action as they saturate with the moisture content from the compressed air. It does not require any additional systems involved and in the context of heatless air compressor dryers, this regeneration phase helps to reduce the heat retained during the adsorption.
Sorbead India is one of the leading manufacturer of activated alumina balls over the years. The quality of desiccant balls, a wide range of quantities available, and easy access to products has helped us remain your trusted partner in all kinds of desiccant requirements. Our heatless compressor air dryer desiccant balls have proven to be highly efficient.
Activated alumina is one of the high performing desiccants among its counterparts. It is used for the purification of various liquids and gases. Been available in various grade, activated alumina balls have a huge surface area that can go above 200 sqm/gm.
AD101 is the finest grade of activated alumina balls as it has a surface area of around 415sqm/gm. It is made of aluminium oxide and ranges from 1 - 3 mm (2mm), 2 - 5 mm (3.2mm), 5 - 8 mm (6.2mm), etc.
Activated alumina balls specifications and parameters (AD101) are as below:
Bulk density (Kg / m3 )
BET Surface area (m2 / gm)
Pore Volume (cc / gm)
Adsorption Capacity (60% RH)
Attrition Loss (%)
Application of AD101 grade alumina balls
Being an excellent performing adsorbent, AD101 grade alumina finds its application in compressed air dryers, air separation plants and heatless air dryers. One of the major applications is the fluoride removal by activated alumina. Fluoride levels in water if crosses a level can prove dangerous and lead to fluorosis.
By letting water through these powerful desiccants, the fluoride content from water is adsorbed that reducing the levels from 5ppm to less than 1ppm.
Other applications of AD101 grade alumina balls are removal of HCL from contaminated gas flow, Catalyst Bed Support, and Drying of Feed air to N2 – O2 Cryogenic plan,
Sorbead India is one of the prime activated alumina suppliers and manufacturers who deliver high-quality products to their clients across the globe. Contact for more details
If you wonder the connection between dew point and activated alumina then here, we are explaining the same to you. But before we get into more details let us define dew point first.
What is the dew point?
Dew point is the temperature below which water droplets start to condense and form dew. To reach dew point the air is cooled. This condensation process happens in stages. Once the air is cooled at first it becomes saturated with water vapors, next it forms liquid water and finally upon reaching dew points, the water vapor condenses and forms dew. Dew point measures the atmospheric moisture. Greater the dew point greater will be the moisture content in the atmosphere.
Use of activated alumina ball for better dew point
Activated alumina is used for various industrial applications to remove moisture content or impurities. With excellent surface area, perfect mechanical strength, great resistance to thermal shocks, activated alumina is used in multiple applications. Be it activated alumina for gas drying, activated alumina for fluoride removal or activated alumina for water treatment, all of these procedures require a dew point to be reached -40 ° C.
Conditions such as compressed air dryers where the reaching of dew point is quite an affair, activated alumina can be used. Most of the manufacturers design their activated alumina to give a dew point of -40 ° C (to the minimum) but under certain conditions such high pressure-activated alumina can be used to giver a dew point of -70 ° C.
Make proper use of activated alumina for better dew points. Only buy high-quality and good grade ones and never overuse the activated alumina.