Activated carbon filter for water

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Updated on: 12/30/2020

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What is an activated carbon filter?

An activated carbon water filter is a versatile drinking water filter for every household, but not for every application

Today, consumers have a wide range of water filters at their disposal. There are various methods of filtering drinking water, for example reverse osmosis, ion exchangers or activated carbon filters. Water filters with activated carbon filters are widely used. But how do they work and what are these filters all about? Are they suitable for every household? What do I have to consider when buying an activated carbon filter?

What actually is activated carbon?

To understand the effect of an activated carbon filter, you need to know what activated carbon actually is. Sometimes one also speaks of medicinal charcoal or activated charcoal.

At the end of the 18th century, it was discovered that charcoal has a so-called adsorption effect, i.e. it removes certain substances from water or a gas. For example, it can decolorize liquids. In 1901, a patent marked the beginning of modern activated carbon production.

Today, activated carbon is obtained from plant materials. Coconut shells, for example, provide a high-quality activated carbon. However, peat, wood or brown coal can also be used. This raw material is carbonised using a process known as "pyrolysis". In this process, the carbon remains, while other components burn. In the second step, this coal is activated in a furnace using chemical processes or hot gas. The aim is to obtain a porous structure of largely pure carbon.

A sintered activated carbon block

Sintered activated carbon block

What does an activated carbon filter consist of?

At the end of the manufacturing process, a labyrinth with many pores is created. This activated carbon has a very large surface area. Its structure is fundamentally different from non-activated carbon.

How does an activated carbon filter work?

What is the activity of the processed activated carbon? The special surface structure increases the so-called adsorption level. This means that substances are enriched on the inner surface of the carbon pores and adhere to the porous surface. Therefore, activated carbon is excellently suited to remove substances from water, but also from gases. 

Activated carbon under the microscope

Activated carbon under the microscope in our laboratory

How is an activated carbon filter used?

Today, activated carbon filters are used in air purification and in the treatment of groundwater and wastewater. However, they are also particularly suitable for the treatment of drinking water and for improving water quality. Due to their versatility, they can be used in industrial environments as well as for water filters in private households. They are both cost-effective and very efficient.

Activated carbon filter for a tap filter

Activated carbon filter for the tap

What are the differences between activated carbon filters?

The efficiency of an activated carbon filter can vary. As a result, there are large differences in quality, which are related to the manufacturing method. In general, there are three forms of activated carbon products:

  • powdered activated charcoal
  • crushed activated carbon as granules
  • shaped charcoal

Particularly high-quality activated carbon block filters can be produced, for example, by sintered activated carbon. This optimises the "performance" of the activated carbon, because with a filter made of activated carbon granulate, the water flows around the granulate, which means that possibly undesirable substances can be released back into the filtered water. The different product properties therefore determine the efficiency of an activated carbon filter.

What does an activated carbon filter filter?

High-quality activated carbon filters remove pollutants and taste-reducing substances from the water. In the process, dissolved substances such as chlorides and organic impurities are also removed. In this process, the activated carbon works like a magnet that holds on to these substances. Activated carbon filters are mainly suitable for filtering the following substances:

List of elements. What filters an activated carbon filter?

Which substances can be filtered by activated carbon?

How does an activated carbon water filter work?

In the activated carbon filter, the water is treated by flowing through the activated carbon block. In addition to the adorptive (i.e. "absorbing") effect, the filter also has a mechanical and catalytic effect.

Does an activated carbon filter also remove minerals?

A good activated carbon water filter also has the property of leaving important substances in the water. These include minerals that are important for the human body. Nitrates and lime are also not filtered through an activated carbon filter - another reason why water filters with activated carbon are well suited for the household and for the filtration of drinking water. But how safe is a water filter that only binds certain substances in the water?

How safe is an activated carbon filter?

The decisive factors are the product quality of a drinking water filter made of activated carbon and the perfect condition of the water filter. Activated carbon has a limited storage capacity. As soon as this is exhausted, the filter cartridge must be replaced; otherwise, not only would the effect diminish, but there would also be a risk of contamination. In addition, it depends on the overall design of the filter product, such as which other mechanical processes for water filtration are installed in the filter. The consumer can find out the safe efficiency of his activated carbon filter from certificates and manufacturer's specifications. Filters are tested, for example, by the TÜV or relevant university institutes. In a special environment, for example in hospitals, or for the safe removal of legionella, special filters must be used that meet standardised requirements and carry out so-called ultrafiltration.

Woman drinks water filtered with activated carbon

High quality activated carbon makes the difference

How often do I have to change the activated carbon filter?

As a rule, the filter cartridges are changed at intervals of between four and six months. Today's activated carbon filters can be replaced without any problems. The flow rate of the water is also decisive. For example, a filter change may be necessary after 5,000 litres. Corresponding information and replacement filter cartridges can be obtained from the respective water filter manufacturer.

Change activated carbon in time and regularly

Timely and regular change is very important.

Are activated carbon filters expensive?

For water filters with activated carbon filters, there is a very large product selection from the table jug filter to the high-performance water filter. Accordingly, you can buy an activated carbon water filter for little money. However, there are also more elaborate, expensive filter systems. A big advantage of the activated carbon water filter is that it does not require any additional chemicals or electricity. Also, installing a water filter is usually easy and can be done without a handyman. In the long run, the investment in a high-quality activated carbon block filter is worthwhile, as it offers more safety and remains maintenance-free except for changing the filter cartridge.

For whom is an activated carbon filter the right choice?

For private consumers and normal households, an activated carbon filter for the water pipe is a good choice because it combines most of the advantages. The filter products are inexpensive compared to other filter systems and deliver high efficiency. For special requirements, for example the need for extremely safe filtering of viruses and bacteria, it is advisable to contact the dealer or manufacturer to find the appropriate product.

Is an activated carbon filter environmentally friendly?

Good activated carbon filters are characterised by a low proportion of binder, which is used in virtually every sintered blank. Alb filter also produces cartridge receptacles from the Lignin as a bio raw materialwhich comes from renewable raw materials.

What should I consider when buying?

Activated carbon filters for water filtration are widely used today. When deciding on a drinking water filter with activated carbon should pay attention to the following criteria:

  • What type of activated carbon product is it? (for example granules or sintered activated carbon)
  • What efficiency is guaranteed by the manufacturer?
  • Is it a sustainable and environmentally friendly drinking water filter whose materials can be recycled?
  • Do I have a very high water flow and how often do I have to change the filter cartridge?
  • Does the product promise trouble-free installation and quick, uncomplicated replacement of the filter cartridges?
  • Does the manufacturer offer a reminder and consultation service?

bottom line

Activated carbon filters offer the most advantages among the common methods for water improvement. They are particularly suitable for private households that want a taste- and odour-improving effect as well as extensive removal of pollutants from their tap water. At the same time, activated carbon filters have limitations when it comes to removing bacteria, viruses, and inputs in the water, such as nitrates. Activated carbon filters are usually user-friendly and comparatively inexpensive. Depending on personal requirements, the advice of a manufacturer or dealer is important when deciding on an activated carbon filter.

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