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Bio digester toilets are bio degradable systems that turns solid waste into organic manure for a safe disposal into the environment.

These toilet waste digesters aim to address the liquid and solid waste water treatment issues associated with traditional means of waste water treatment methods that we have become accustomed to and grew up using.

Some of these methods included the use of pit latrine, ventilated pits (KVIP) and more modern waste treatment means like cesspit, culvert tanks and septic tanks.

What is different from these other toilet waste management systems in Ghana?

Unlike the cesspit and septic tanks that requires periodic emptying, biofil waste toilet bio digesters as the name suggest are biodegradable and does not require emptying (dislodging) the way septic tanks require trucks to do that.

Before explaining how this is done, the bio digesters described in this article are NOT those that produce gas for domestic purposes that have come up lately in Ghana.

Here are the Eleven facts about biodegradable digesters that you need to know:

FACT 1: Where do they come from: 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 Ghana Government with the aid of the World Bank agreed that considering the sanitation situation especially in low income households in Accra, these biodegradable waste digesters from the test of the effluent level would avert the problems we have in the way human waste is managed traditionally in Accra and its environs.

The Government through the GAMA Project has since been constructing these digesters for home owners in low income areas. This technology has proven to be a better option than traditional foul smelling cesspits and septic tanks in Ghana and has since helped considerably in reducing the problems brought about by the lack of effective human waste management systems

FACT 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 waste treatment systems in Ghana.

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

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 anaerobic digestion is adopted.

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

Flushed water and solid waste enter at the top of the 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 in the environment.

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 or can simply be stored in a tank through enhanced filtration and the waste water can be reused to water flower plants flowers on your compound .

A typical soak hole pit under construction for use by a bio digester

FACT 4: Waste Water Soak Hole Pit 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 going to be.

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 to allow for easy filtration of the waste water into the digester.

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

FACT 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 provides an enclosed space where the activities of the self-perpetuating population of earthworms and micro-organisms are optimized and used together with porous or wire mesh filtration are used to facilitate the rapid solid-liquid separation as well as to serve as attachment site for the micro-organisms in addition to coconut fibre which is used as the bulking material. 

it 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.

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 emptying.

FACT 6: Reasons why people choose bio digester toilets in Ghana

The cost and pricing of bio digesters in Ghana has become a tussle point for some home owners interested in digester waste toilet construction. Even though some have claim they are too expensive, in comparison to septic tanks there’s no doubt they have become the choice for most home owners in Ghana today.

FACT 7: Bio digesters Cost less to construct (install) 

The cost and pricing of bio digesters in Ghana has become a tussle point for some home owners interested in digester waste toilet construction. But the truth is they are cheaper to install (as compare to digging a manhole or buying culverts for septic sewage tanks). The land space needed, the material list needed for construction all goes to attest to their low pricing as compare to other waste management systems.

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

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.

FACT 8: Biodigesters are the most eco friendly biodegradable 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.

Biodigester toilet tank designed for use as a waste water management option for home owners in Ghana

FACT 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.

FACT 10: Ground water not affected

Water is directed into top soils where microbial activities are most active. Nutrients are removed by soil bacteria decomposition. Because of the depth of the digester (about 3 feet depth) ground water is not affected.

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

FACT 11: Biodigesters have international approval

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

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