Carbon sorption filter to buy

Table of Contents

1. What is a sorption filter? Scope of application of sorption filters
2 Types of sorption filters 2.1 Sorption filters with cartridges
2.1.1 Trunk sorption filters with Slim Line type carbon cartridges
2.1.2 Main sorption filters with Big Blue type carbon cartridges
2.2 Sorption filters of backfill type with activated coconut or birch charcoal
2.2.1 Description
2.2.2 Construction of the backfill filter
2.2.3 Principle of operation of the sorption filter of the backfill type
3. Comparison of technical and economic indicators of different types of sorption filters

1. What is a sorption filter? Scope of application of sorption filters

Sorption water treatment allows the removal of chloride compounds, fine suspended solids, colloids and dissolved gases. In addition, sorption filters have a positive effect on the organoleptic properties of water, eliminate unpleasant odor and taste, make it transparent. Passing water through sorption filters can also get rid of petroleum products, pesticides, asbestos, herbicides, organic compounds and bacteria.

Sorption filters are used for deep purification of wastewater, in closed water supply systems. The filtering substance is various activated carbons, the most effective of which is considered to be coconut. Coal from coconut shells has a longer service life, as it is characterized by significant resistance to abrasion, as well as it has a greater adsorption capacity.
Water purification with activated carbon loaded sorption filters is considered one of the most optimal methods of fine purification. Activated carbon has the ability to trap microscopic particles of solids adhering to the filter granules.
The principle of operation of carbon filters is based on the process of retention of pollutant molecules by the external surface of carbon granules - this phenomenon is called adsorption. The method of sorption with a fixed and dynamic layer of sorbent is successfully applied for the purpose of wastewater treatment in industrial sectors. Also sorption filters are productively used for water purification in country houses, cottages. Sorption filters are cartridge and backfill types.

2 Types of sorption filters

2.1 Sorption filters with cartridges

Carbon filters with replaceable cartridges are the most popular design. The carbon is inside an outer mesh shell, which can be made of polypropylene, polystyrene or polyethylene. Thanks to the mesh shell, the filter media is retained inside the housing and large mechanical particles are filtered.
Sorption carbon cartridges are able to purify water from most pollutants, such as inorganic and organic suspended solids, petroleum products, heavy metals, free chlorine and others. Silver may be added to give bactericidal properties. The size of the body is one of the important parameters of carbon cartridges. There are two series, differing in diameter and filtering resource: Slim Line and Big Blue.

Fig. 1 - Connection diagram of the cartridge sorption filter

2.1.1 Trunk sorption filters with Slim Line type carbon cartridges

The diameter of Slim Line cartridges ranges from 61 to 73 mm. These cartridges are designed to treat a small volume of water and are suitable for use in drinking filters (flow and RO) and are also found in relatively small mainline filters. They have a transmitting capacity of up to 1.5 m3/hour. Universal - applicable with filters of most manufacturers. The operation of the filtration system is carried out as follows - the initial water falls on the outer plane of the cartridge, then passes through the wall. As a result, contaminants are trapped on the surface and wall of the filter element. After that, the already purified water, having risen through the channel located inside, gets to the filter outlet.

Fig. 2 - Slim Line 10" carbon cartridge

2.1.2 Trunk sorption filters with Big Blue type carbon cartridges

Big Blue cartridges vary in diameter from 112 to 117 mm. They are used for purification of a larger volume of liquid, as their capacity is higher than that of Slim Line cartridges (due to the larger diameter) and is up to 6 m3/hour. They are most widely used in mainline sorption filters. Big Blue cartridges can be of different heights, which also characterizes the increase or decrease of throughput capacity.

Fig. 3 - Big Blue 20" carbon cartridge

2.2 Backfill type sorption filters with activated coconut or birch charcoal

2.2.1 Description
Sorption filters of the backfill type successfully cope with the task of improving the organoleptic characteristics of water due to the adsorption properties of activated carbon and the discharge of suspended solids into the drainage by backwashing. The backfill type filter is a volumetric tank loaded with a filtering substance. The composition of the backfill and the construction of the filter may vary according to its purpose. The undoubted advantage of backfill filters is that they can be operated for a long time without replacement due to regular washing (regeneration).
Sorption filters are divided into two types depending on the regeneration of the filter media:

• Backwashing with a reverse flow of water, without additional use of chemicals.
• Regeneration of the cleaning capacity with the use of special chemicals.

2.2.2 Construction of the backfill filter

Structurally, a sorption filter includes three main elements: a housing with a distribution system, a filter medium and a control unit. Due to adsorption properties of activated carbon (filtering medium), when water passes through a layer of loading, the contaminants present in it are absorbed.

The material of the housing is usually fiberglass or stainless steel. The housing has a cylindrical shape with a dome-shaped top and bottom, which creates the best hydraulic parameters of the filter during operation. Stable installation is guaranteed by a ring base. Charcoal loading is carried out through a special opening in the upper part of the housing.

The control unit is a multi-way valve with hydraulic or electromechanical actuator and automatic control (there are also variants with manual control). The main purpose of the control unit is to initialize the regeneration process, i.e. the systematic switching of water flows according to the set program. There are control units with time and flow regeneration, which include a timer or a water meter respectively. There are also control units with regeneration based on the analysis of water quality characteristics.

The filter medium, as well as its quantity, is selected and calculated based on the parameters of the source water, as well as the purposes in which this water will be used after treatment. The backfill may consist of one or several types of filter media.

Fig. 4 - Design of backfill sorption carbon filter

2.2.3 Principle of operation of the sorption filter of the backfill type.

When water passes through the filter, contaminant molecules are transported on the surface of the filter medium and are trapped in the pores of the activated carbon. As the upper layers of the backfill become saturated, filtration is transferred to the layers below. There comes a condition when the whole thickness of the filter medium is saturated with particles of contaminants and the required quality of water purification is no longer achieved. When this happens it is required to carry out regeneration, i.e. washing of the loading layer by reverse water flow, which is carried out, as a rule, in automatic mode with the help of control unit. After flushing, the flushing water is transferred to the drain. Despite this measure, periodically the filter media needs to be completely replaced, as it loses its cleaning properties over time.

  (1)(2)

Fig. 5 Operating principle of backfill type filters (1) - filtration mode (2) backwashing mode

3. Comparison of technical and economic indicators of sorption filters

To understand the feasibility and cost-effectiveness of using different sorption filters, and therefore to make the right choice taking into account the purpose of purification, below is a comparison table of devices offered by Wagner-Ural.

Table 1 - Comparison of characteristics of cartridge and column type sorption filters

Conclusions: Thus, we can conclude that for an apartment with a small amount of water consumption is most suitable cartridge-type filters, while for a private house with high water consumption or enterprise it is advisable to use filters of the backfill type, preferably with coconut charcoal despite its higher cost. Since the service life, sorption capacity of coconut coal is many times higher than similar volume of birch coal.