Maapuhdistamoilla tarkoitetaan jätevesijärjestelmiä, joissa jätevedet puhdistetaan maaperässä.

Soil treatment/­septic tank

An efficient and simple solution for large sites

Infiltration fields are simple and natural ways of handling domestic wastewater wherever it is created. The only requirements are space for a purification field and a professional design to implement it. Infiltration plants are wastewater treatment systems in which wastewater is purified in the soil. The infiltration package includes a septic tank and a purification field, which can be an infiltration plant or sand filter plant, depending on the type of soil on the site.

Infiltration is an excellent solution when

  • an efficient and simple solution is required for treating the domestic wastewater created by a single family
  • the plot is large and is not located near a body of water or in a groundwater area

Infiltration solutions are divided into two groups according to wastewater type. Infiltration plants intended for grey water can only process domestic wastewater from showers and washing. Infiltration plants intended for all types of water can accept all domestic wastewater: both grey water and sewage.

With infiltration

Sludge separator with subsequent infiltration

In an infiltration plant the wastewater cleans the existing soil by flowing through the natural soils and spreading through the ground to the groundwater.that is, the sewage is filtered through the soil layers. In the transition between the dispersion layers (macadam) and the underlying soil layers a biofilm is formed, where a biological reduction of organic matter and contaminants occur before the wastewater reaches groundwater.

Traditional infiltration with sparge and macadam

The most common type of subsequent purification to sludge separators is traditional infiltration, which is built by spreader tubes and macadam

Constructed infiltration with infiltration modules

Works as a regular infiltration facility, but the biological purification occurs in the infiltration module. This option is usually used when it is difficult to get macadam or when the location of the plant makes it impossible to carry heavy masses.

With sand filter
A land bed is basically based on the same process as an infiltration facility. The plant type is used when the soil layers consist of silt or clay. Meaning, you can replace the dense soil layers with an "artificial" earth type (soil bed sand). In order to be able to build a groundbed facility, an outlet type is required: dike or watercourses that can receive the purified water.
With phosporous removal

In case of extra purification of phosphorus

When the requirements for reduction of phosphorus are high or when laying a soil bed, the plant must be supplemented with phosphorus precipitation. The precipitate takes place in the sludge separator and is flow controlled. After the precipitation, the wastewater is led to an infiltration or a soil bed for further treatment.

Solutions for grey water

Domestic wastewater from showers, washing up and personal washing is purified by the soil using a sand filter or infiltration system. The 1 m³ infiltration package is intended for cleaning the grey water produced by one family. The infiltration plant can complement a sand filter using a 2 x 15 m collection pipe pack.

If the space is limited, an infiltration module solution can be selected instead of a traditional field. Such a solution only requires around 10 m² space. Infiltration modules made from mesh pipes replace the infiltration field's distribution layer while purifying wastewater more effectively than a traditional layer of macadam.

When the purification field is higher than the septic tank or if the height difference is not sufficient for gravity sewerage, a Uponor pump chamber can be added to the system if required. The pump chamber is located after the septic tank. Grey water septic tanks generally need to be emptied once every two years at holiday homes and once every year at permanent residences.

Solutions for all types of water

A single-family leaching field for all wastewater consists of a 2 m³ septic tank, a divider drain and an absorption or infiltration field. Larger septic tanks and fields can be used to build infiltration systems for two or three families.

On small plots the purification field can be built using absorption modules, which require less space. Infiltration modules made from mesh pipes replace the infiltration field's distribution layer while purifying wastewater more effectively than a traditional layer of macadam.

Additional phosphor removal can be obtained using a separate phosphor removal chamber, which is installed between the septic tank and the leaching field. The septic tank is ordinarily emptied twice annually.