16TH April 2023
Attn: Mr. Ramsey
Dear Sir,
RE: A PROPOSAL SOLUTION TO YOUR SEWERAGE TREATMENT AND DISPOSAL
With reference to our understanding at ENB Fluid Solutions, we are aware your adoption of Sewage
Tanker Trucks to often empty your Septic Tanks. This is a costly approach in the long run and it does
not offer a complete solution to the underlying problem. Our expertise would like to propose a simple,
affordable and efficient way to mitigate this issue permanently
At ENB Fluid Solution we always offer customize our solutions based on client needs and importantly
clients budget without compromising on delivery. Our performance track record has covered mainly
Somalia and Kenya, some of our satisfied customers in Somali include the military camps at the Airport
vicinity.
Background Idea on Proposed Solution.
An estimate of about 70%-85% of the total matter in a septic tank comprises of liquid waste i.e. Grey
water (wash water, washrooms water, kitchen water) and Black water (toilet water, urinal waste water,
urine).
The constituents of both grey and black water is further changed due to introduction of detergents,
shampoos and other washing chemicals. With their introduction they affect the operation of the septic tank
as an Anaerobic Digester as they hinder microbial life and activity in the septic tank by increasing the
COD (Chemical Oxygen Demand). This leads to slow digestion in septic tank and due less matter
breakdown reducing septic tank holding tank capacity overtime. This means with time the septic tank shall
tend to hold less matter as compared to the initial volumetric design purpose.
From above removal of grey and black water with an integrated disinfection unit before disposal to a leach
field can be adopted with automated and sustainable design. This will reduce grey water accumulation
levels and may significantly reduce the COD levels, giving a chance the microbes to continue with digestion
of the solid faecal matter.
Upon a site visit, which will enable us to do the tank sizing, dosing rates and pump selection calculations.
The client is also required to identify a selected unused and probably unplanned piece of land for the Leach
Field. Other advanced treatment methods maybe included after the client feels the need for further
treatment.
The mixed grey and black water shall follow the stages;
 The grey and black water shall be pumped from the Septic tanks using specified cutting impellertype sub-pumps to a constructed holding/settling tank. Prior to reaching the holding/settling tank a
gravity/electric/mechanical inline dosing Cl-65 unit shall introduced along the line to disinfect the
water
 Also an inline dosing Floc unit shall be induced to increase the settling rate in the holding/settling
tank. The design of the tank and the positioning of the pump shall be optimized to allow for up to 80%
settling before being transferred to the Dosing chamber.
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The dosing chamber shall allow for a steady flow towards the leaching field to allow for optimal
leaching before the next batch of waste water is pumped, this is done by a calibrated interlock
switching of septic tank pumps, holding tank pumps and rate of leach field dosing
In the final stage the waste water is allowed to undergo leaching in the special constructed leach
field. The Leach Field is excavated with the determined depth and filled with gravel, as per the
volume load correctly sized pipes are selected and are perforated before being laid out in the field.
The Leach field area is finally covered with excavated soil, leveled and blends with the
environment. The field is usually chosen outside the camp on unused land.
Finally, the whole process is automated and requires no human intervention unless on periodic checks
regarding addition of dosing chemicals and sound operations of the pumps.
Fig 1: Process Flow Diagram.
Conclusion
We hope to hear from you soon in regards to the above and incase of other water based projects.
Yours faithfully,
Edwin Jamenya.
TEL: +252-610-660-242
:+254-794-432-341
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