ZLD Sewage: 0% discharge & energy surplus


In the best of cases, human sewage from WWTP plants ends up in being transported from the plant to a landfill or incinerator. In both cases, transport and the service of a waste manager add a significant additional cost, apart from the environmental problems they cause.

In the worst of cases, sewage ends up in rivers, seas or directly in subsoil, presenting even greater problems for human health as well as for the environment.

Essentially, up to the present moment in time, there has been no technology that ensures the revalorisation of human sewage, presenting the world population with a constant problem.


With the IKERA RD8 technology, two solutions are provided for the management of human sewage.

In both solutions, the solid part is free of all types of pathogens.

The first solution is the reuse of the solid part as biomass energy on site.

By doing this we obtain highly pure water which can be reused and on site biomass.

The second solution is the reuse of the solid part as fertiliser, reusing the water according to requirements and parameters.

Most importantly, preventing sewage from being transported to incinerators or landfill benefits both economically and environmentally.


With the IKERA RD8 technology we offer 2 different proposals.

In the first proposal, we transform the sludge from the original 80% water – 20% solid, to a combustion-friendly biomass by reducing the concentration of water to less than 10% and also reducing the nitrogen concentration.

In this process the solids can be reused as an on site source of energy,  making the Ikera RD8 plants energy surplus.

Another of our specialities is combustion of biomass. We apply our own “know-how” and patents on our burners which allow us to successfully combust sewage and many other organic wastes where conventional systems can not.

The second proposal involves reusing the solid part as fertilizer. The energy consumption would have to be satisfied with renewable energies such as CSP, mini-CSP, geothermal, local biomass or a combination of them. Alternatively, non-renewable energies can be used solely or in combination with renewable energies.

In both cases, the solid as well as the water are free of pathogens due to the same process of separating the water and solid.

The process begins by introducing in-continuous sewage into a tank in which we ensure homogenisation after which the process continues through the  IKERA RD8 physical reactor. Here only H2o is evaporated and subsequently condensed.

This water is of great purity and depending on its final use will go through a final  process involving traditional water mineralization methods or will be directly used or stored.

The solid part is taken from the reactor and stocked in its dry state for use as biomass or as fertiliser.

In both cases, during the internal process, pathogens such as typhoid, cholera, hepatitis or helminths implode.

The nitrogen can be left in the water, left in the solid part or separated, depending on the final use of the solids and the water.


We have carried out feasibility studies into over more than one hundred organic types of waste waters including sewage from WWTP, chicken manure and pig slurry.

As well as having experience using the process of dehydration we also have extensive expertise in combustion and poly-combustion, having managed to combust orange peel, coffee grounds, slurry, manure and many others with humidity levels between 3% and 10%,  leaving the ashes at a humidity level of less than 1%.

We are looking for industrial partners or venture capital for industrial scaling.

Readings of interest

American Chemical Society
Sewage Sludge as a Biomass Resource for the Production of Energy: Overview and Assessment of the Various Options†
Wim Rulkens

Hunan Academy of Forestry, Changsha, China
Co-pelletization of sewage sludge and biomass: The energy input and properties of pellets
Author: HuiLiabLong, BoJiangacChang, ZhuLia1JieLiangc, Xing-Zhong, YuancZhi-, HuaXiaoc, Zhi-HongXiaoa, HouWangc

IOP Science
Wastewater sludge to energy production. A review
N Vatachi1

Sewage sludge gaining attention as biomass resource