12 Awesome Facts You Need To Know About Bio Digesters in 2019

Bio digester toilets (biofil) are bio degradable systems that break down human solid waste for safe and easy disposal in the environment.

These toilet waste digesters address the liquid and solid waste water treatment issues at both residential and public or commercial  facilities.

This is in sharp contrast to septic tanks and traditional manholes that requires periodic dislodging of the human solid waste by a truck.

Before explaining how this is done, it’s worth noting that the kind of bio digesters here are NOT those that supposedly produce gas for domestic purposes.

DreamHouse Standard Family Size Bio Digester
DreamHouse Standard Family Size Bio Digester

We have answered the most frequently asked questions by our prospective customers here.

1. History of Bio Digester Toilets in Ghana 

The history of bio digesters in Ghana is not clear but they became prominent after the 2014 severe cholera outbreak in some parts of Accra.

The Government of Ghana and the World Bank then decided that considering the sanitation situation especially in low income households here in Accra, bio digester toilets were our best bet. This was considered and compare to what Ghana as nation is used to in terms its methods of human solid treatments disposals.

We are used to using septic tanks which is a large holding tank designed to store human waste materials which must be periodically removed from by pumping.  

The Government through the GAMA Project has since been implementing this policy through the installation of  low cost bio digester toilets.

In fact using bio digesters as an integrated toilet waste water management system is nothing new.

In some parts of New Zealand, Samoa Islands and Papua New Guinea these eco-friendly biodegradable waste toilet digesters are used effectively to solve waste water treatment issues and the organic manure that comes out are used to enrich their soil for organic farming.

This technology has proven to be a better option than traditional foul smelling septic tanks in Ghana.

Large Family Size Bio Digester: Ideal for 5-8 bedroom houses
Large Family Size Bio Digester: Ideal for 5-8 bedroom houses

2. How do bio digesters work?

Bio digesters eliminate toilet waste water odors by over powering the natural occurring bacteria mostly found in septic tanks and man holes.

For example in biofil digesters, the waste water from the flush unit (water closets) is organically filtered through a porous slab, allowed to penetrate a small rock-filled soak hole from which it leaches into the soil.

In places where there are gutters, the black water is organically filtered out of the bottom of the digester and drained into them.

Bio degradable toilet waste digesters have established themselves as the modern day answer to KVIPS, pit latrine and septic tanks as toilet treatment systems in Ghana.

3. Where does the waste water from a bio digester go?

There are a lot of misconceptions around bio digesters as an effective toilet waste water management system.

One of the most asked questions is where does the flushed water from a water closet goes.

Usually people are not sure how such a small box can contain all these water and serve a whole household with out getting full.

But because bio digester toilets are used as part of the process of treating bio degradable toilet waste water and sewage sludge, the process often referred to as aerobic digestion is adopted.

Natural composting organic manure are introduced to treats all organic bio degradable materials through the natural process of aerobic decomposition.

Flushed water and solid waste enter at the top of the DreamHouse bio-digester where immediate separation of solids and liquid contents of the waste occurs.

All liquids will then be organically filtered out of the bottom of the digester and drained into the soil where further and final decomposition occurs.

Other solids (toilet rolls & all degradable cleaning materials) are decomposed and converted into rich & safe soil for easy disposal.

Typical soak hole construction for a bio digester
Typical soak hole construction for a bio digester

Now the final effluent (waste water) produced is a clear odorless liquid suitable for discharge either into a waste watercourse, through a customized soak hole trenches or a drain filled system.

4. Waste Water Soak Hole Construction

We fill the bottom of the soak hole with a layer of rocks. With each rock about 3” in diameter.

The layer of large rocks we determine how many inches high they should be based on how the depth of the soak hole is.

A typical construction of a soak hole must ensure that the bottom of the soak hole is 2’6” below the bottom of the leachate pipe hole.

The depth of the soak hole from the surface of the ground will depend on the water table for the toilet site.

Regardless of how deep the digester bed hole is, we maintain the bottom of the soak hole at the above given specifications.

5. What Becomes Of The Solid Waste In A Bio Digester?

Because the bio digester is a simple compact onsite organic waste treatment system it essentially uses a biological filter consisting of a fiber, medium of black soil and in some cases porous concrete. The bacteria and other organisms generated through this technology then bio degrades solid waste.

So for the lay person the immediate question that comes into mind is “what becomes of the human remains in a bio digester and how does it look like”?

When the digesters get the maximum per day uses, it will take at least 5 years and as much as 15 years in some cases for the toilet waste box to get filled up and ready for dislodging which involves scooping out the human remains (manure) with a shovel for easy disposal.

The solids waste and human waste remains are harvested as pure compost which can be used for agricultural purposes after years of usage. The harvesting time depends on the number of users in a given facility and type of soil on which the bio digester was installed.

This is totally new to what we have been accustomed to over the years whereby a tanker shows up to collect solid waste which often find its way into the sea.

In highly developed countries, the process is used for industrial or domestic purposes to manage waste and reduces the emission of landfill gas into the atmosphere.

6. Reasons why people choose bio digester toilets in Ghana

Even though bio digester toilets cost has come up lately for public discussions, there’s no doubt they have become the choice for most home owners in Ghana today.

Whiles there are no concrete research available that shows the exact percentage currently adopting these waste water treatment method, there is no doubt that they are effectively helping to help improve the sanitation situation in most homes.

7. Cost less to install 

They are cheaper to install (as compare to digging a manhole or buying culverts for septic sewage tanks).

Even the idea of digging all those feet’s and doing all those concrete works makes bio digesters your best bet any day.

Bio digester under construction on site
Bio digester under construction on site

8. Eco friendly technology

Bio digesters are the most environmentally safe and highly improved means of treating toilet waste water in Ghana today.

The use of locally sourced materials means that they are safe for the environment

They are easy to maintain and do not come at any additional cost to the home owner.

9. No more dislodging

There have been some misconception about this saying.

But what we are simply saying is that with DreamHouse bio digesters, you don’t need a typical truck to show up saying they are there to empty your tank.

Because digesters uses an aerobic digestion process, solid waste after a cycle (which usually last between 5 to 8 years) changes into sand (manure) which can easily be disposed of at your backyard.

As a result, no septic sludge is stored and as a result the bio digester product has a unique ‘odour free’ operation guarantee.

10. Ground water not affected

Water is directed into top soils where microbial activities are most active.

Nutrients are removed by soil bacteria decomposition.

Digesters are designed above ground and typically has no more than a week of decomposed contents in them.

11. Internationally approved 

Not only do bio digester toilets in Ghana have governmental approval (you can check from the nearest District Assembly), they have also received worldwide acceptance by the World Bank.

In fact over the last 5 years the Government of Ghana has received over $150 million in grant  from the World Bank as part of a project complementing efforts to provide low-income households with increased access to improved sanitation and water supply.

Simply put our bio digesters are safe for everyone; private homes, offices and public needs.

Newly installed bio digester for a five bedroom house in Accra
Newly installed bio digester for a five bedroom house in Accra

12. Customer guarantee and support service

Because bio digesters are new to Ghana, some of our clients are not sure about their effectiveness in terms of its waste water management prowess.

Others are also not sure of how long they will last after installation.

That’s why at DreamHouse we provide a customer guarantee and all year round support services.

Installation of a bio waste digester plus a soak-hole pit can all be done in a day if precast slabs are used. Two days if blocks are used.

Except plumbing works, the cost of a bio digester toilet installation is inclusive in the total digester cost.

Call or WhatsApp us today on +233(0)556398805 and +233(0)245424644 for FREE estimates and quotes.