Waste water in the septic tank
What types of wastewater are discharged?
A septic tank can contain different types of water. These types of wastewater are differentiated according to the waste products that end up in the water.
A distinction is made between the following types of water in septic tanks:
- Black water
- Grey water
What is black water?
This is the case when only toilets are connected. Black water is toilet flush water that consists of flush water, urine and faeces. Black water owes its name to the colour it usually gets from the waste products it contains.
This type of wastewater contains the following substances, among others:
- organic substances
- fertilisers
- drug residues
- toilet paper
- hormones
- Pathogenic bacteria from urine and faeces
- Large quantities of flushing water
What is grey water?
Grey water consists of a collection of bath water, shower water, washing machine water, dishwasher water and water from the kitchen sink. In practice, this means all the water that is flushed away in the house (except for the toilets). Grey water has a very different composition compared to other wastewater. This is of course due to the fact that many different systems are connected to it. In terms of wastewater treatment, it is important to know that there is soap in the water.
This water can consist of the following substances, among others
- Soap residue
- Metal particles from the pipes
- Copper particles from the pipes
- cosmetics
- hair
- Skin flakes
- grease
- cleaning agents
- Food waste
- Detergents/dishwasher detergents
In short, a large number of different substances that can ultimately give grey water its name.
Other types of wastewater
You may also come across the terms yellow water and brown water, although these are not often used. Yellow water is urinal water that contains only urine. Brown water consists only of faeces. This type of wastewater is only produced when only urine is channelled into the tank. Every septic tank consists of bacteria (microorganisms) that break down the waste in the drainage water so that it complies with the drainage regulations. However, each type of wastewater is different. For example, bacteria have a much harder time breaking down black and grey water than yellow and brown water. This is because this wastewater also consists of chemical substances. Substances that are much more difficult for bacteria to break down. It is therefore advisable to have the septic tank serviced regularly and to add extra bacteria to improve the function of the septic tank in the event of unpleasant odours/clogging. Prevention is better than cure? That’s why we have a range of (maintenance) products to improve and maintain the performance of the septic tank.
