Septic tanks are classic ‘bio-digestors’ that rely on anaerobic bacteria to break down human sewage wastes over a period of (at least) 21 days.
Septic systems are used to treat sewage from (usually) single dwellings in districts where municipal Wastewater Treatment Works are not available. Larger systems are also used by rural industries to cater for the disposal of staff effluent.
Conventionally ‘in-the-ground’ septic tanks will run smoothly for many years when they are respected and not overloaded
To perform satisfactorily septic tanks must be:
The septic tank is thought to have originated in France during the early 1800s where it was developed to deal with human wastes generated in the new towns that expanded rapidly to support the industrial revolution following the regime of Napoleon Bonaparte. Until that time, the wealthy used buckets in an ablution room within their house and the staff (chambermaids) emptied the contents when necessary into the same cesspit latrine adjoining the house that they used themselves.
Some larger buildings, country houses, abbeys etc. had quite sophisticated sewers that drained from within the house to a cesspit and associated reed bed in the grounds. Faecal solids were flushed along the pipes (by household staff) using random buckets of wash water.
Large cities had networks of brick or stone built gravity sewers that drained all effluent to the river around which the town had developed. Such disposal methods – along with the vermin that flourished upon the discarded refuse – gave rise to frequent outbreaks of illness, because rivers, such as the Thames and Seine, became contaminated with sewage.
Septic systems have two parts:
A septic tank has three main functions:
Natural anaerobic bacteria and associated microorganisms living within the septic tank adapt to degrade human sewage to simple biogasses, water and inorganic radicals (for example, trace minerals in food).
For this to happen the tank must be:
Also known as a French drain, drainage field or leach field, the soakaway is an integral part of the septic tank system. It allows partially treated effluent from the septic tank to ‘soak away’ into the surrounding soil where it is progressively ‘polished’ back to potable quality as it seeps ever further downwards through the ground towards the natural water table.
A soakaway under construction
The efficiency of the soakaway depends upon:
1) Where soil conditions do not favour soakaways there are two alternatives:
2) Older publications, pre circa 1990, advocate the inclusion of grey water in the septic tank. That was when tanks were larger and generally before the ‘off-the-shelf’ roto-moulded plastic tanks that are commonly installed today, were freely available. Also, in those times the excess N and P, found in laundry water especially, were seen as advantageous to the development of the faecal-degrading biomass in the primary chamber of the tank. However, modern (post 1990) foodstuffs frequently contain high levels of refined micro-nutrients, which fulfill the same task in the smaller volume tanks that economy usually dictates the builder installs today. Many of the elements in modern food contain complex molecular structures which, emulsified in waste water, take time to break down. Many elements resist degradation which is why high performance biological additives (such as our BIO-SYSTEMS STR) are becoming ever more important in balancing the equation.
Diagram of a typical septic tank
Septic tanks rely on naturally-occurring anaerobic microbes that degrade organic wastes (faeces and urine) into simpler organic compounds: natural gasses, water and inorganic radicals. They work without input of energy other than that provided by gravity (water flow).
Source: Bio-Systems SA (contact Bob Hadley for more technical information: info@biosystemssa)
In addition to a vast range of plastic water tanks and other polyethylene products, JoJo Tanks (South Africa) also manufacture a range of plastic conservancy tanks and septic tanks, from 1250 litres to 6000 litres capacity. These tanks are of robust construction and are easy to install. Contact us for a free quote on a JoJo Tanks septic tank or conservancy tank or click on the links below to see JoJo Tanks’ range of chemical tanks, silo tanks, water tanks and steel tank stands.
JoJo Tanks South Africa offer a wide range of plastic water tanks and chemical tanks to suit every household, business or agricultural need, including silo tanks and silo tank stands. See JoJo Tanks VERTICAL TANKS, HORIZONTAL TANKS (transporter tanks), STEEL TANK STANDS and OTHER JOJO PRODUCTS. Also see JoJo Tanks’ NEW 6000 LITRE UNDERGROUND TANKS. Also see our FAQ and WATER TANK PRICES.
JoJo’s superior polyethylene plastic water tanks and steel water tank stands make JoJo Tanks the leaders in plastic water tank technology and the quality, affordability and guarantee on these water tanks make JoJo products the best choice in South Africa. JoJo’s water tanks and chemical tanks come standard with a number of features that are often lacking on cheaper/inferior plastic tanks made by other companies in South Africa.
We are authorised JoJo Tanks dealers in South Africa and dispatch orders directly from JoJo Tank depots to save on transport costs. Full range of JoJo Tanks products and JoJo water tanks for sale. CONTACT US for a quote on the right JoJo water tank or other JoJo product for you. Special discounts are available on multiple orders of chemical tanks and water tanks and to our commercial and government customers.
SPECIAL ON MULTIPLE ORDERS OF 10000 LITRE JOJO WATER TANKS…CONTACT US FOR A FREE QUOTE!
(15000 litre and 20000 litre JoJo vertical water tanks also available on order)