B-ZONE Biodigester Wastewater (sewer) Treatment Plant

BiodigesterOur trademark B-Zone biodigester plant offers an extremely efficient and unobtrusive means of sewage management disposal. It is a three-stage sewage treatment plant manufactured entirely from robust and corrosion free materials. The bioreactor incorporates unique features to ensure simplicity and efficiency of operation. It meets the standard of environmental impact assessment (E.I.A), a requirement for all construction projects. Available in a range of sizes to suit virtually any application from a single residential property, camping site, hotel and restaurant or a major industrial/commercial complex, it meets the specific requirements of each individual situation.


The bio-digester is a far more environmentally friendly way of storing and treating effluent waste compared to the septic tank. It works on a similar basis of a septic tank, however, it does not need to be emptied regularly because the waste that comes out of the ‘Bio-digester’ has been treated so much so that it can be released into the local environment

The bio-digester occupies a small construction area. i.e. 1 square meter for domestic purposes and only 2 square meters for commercial purposes hence leaving greater space for other construction purposes.

It employs anaerobic digestion which is a collection of processes by which microorganisms break down biodegradable material in the absence of oxygen. Human waste is largely organic. This can be degraded by bacteria thus reducing the mass of the waste. The water can then be recycled

It is a system where the treatment of excreta or sewage takes place at the same location where it is generated. This is due to the high cost of installation of a sewerage system. hence the sewage is dealt with where it is generated, offering a hygienic, affordable and cost-effective solution.

The new modern Blueflame limited biodigester system holistically provides the following client and environmental advantages.

  • It is eco-friendly.
  • Does not require frequent exhaustion and drainage.
  • Avoids the problem of dumping and environment pollution.
  • Its effluent is clean water that can be recyclable for cleaning or use in the garden.

What are the current problems in schools that don’t have biodigesters?

  • Latrine system that currently is full and is in need of replacement. The current latrine is in very poor conditions. It occupies an area of 10 m2 and has three rectangular shaped inlets, so human faeces are mixed with urine and other watered materials which have shortened the latrine’s lifespan. There is no doubt that schools need an improved sanitation system to overcome this problem. Moreover, the untreated human and animal waste contains high concentrations of viruses and bacteria, which can cause infection and disease when in direct contact with people, or  when water supplies are contaminated
  • The treatment process in septic tanks attached to toilets also does not break down the waste completely.
  • Thus, sulphuric acid is produced which causes a foul smell.
  • Sewage from the rest flows in open drains, causing river contamination.
  • Untreated waste is responsible for several diseases like dysentery, diarrhoea, amoebiasis, viral hepatitis, cholera, typhoid etc.

What are the advantages of using a biodigester?

  • Use of phenyl is permitted up to 84 ppm
  • The zero-waste biodigester technology breaks down human excreta into usable water and gas through an anaerobic process.
  • The bacteria can work for a lifetime, thus, no need for replacement or cost of purchasing bacteria or enzymes to work in the project.
  • Reduction in pathogens by 99%
  • Reduction in organic matter by 90%
  • Reduces the cost of emptying latrines, once the tanks or pits are full.
  • Reduces river pollution in areas where the water table is high.
  • No need for removal of solid waste
  • No maintenance required, thus cost saving
  • No infestation of cockroaches & flies
  • No clogging of the biodigester
  • No bad smell in toilets from the tanks
  • Methane can be used for cooking while water for irrigation,
  • It does not have any geographical or temperature limitation
  • Faecal matter in the tank not visible
  • Employs microorganisms such as Clostridium and Methanosarcina that can break down excreta.
  • Effluent is free from off odour and solid waste
  • Does not require the set up of large sewerage networks.
  • The slurry is rich in various plant nutrients such as Nitrogen, phosphorus and potash. Well-fermented biogas slurry improves the physical, chemical and biological properties of the soil resulting in qualitative as well as the quantitative yield of food crops.
  • Underground construction minimizes land use
  • Can be built and repaired with locally available materials
  • Can accommodate a wide variety of organic wastes including animal manure, night soil, crop stalks, straw, slaughterhouse wastes, biodegradable garbage and wastewater.
  • Positive use of organic waste materials reduces land and water pollution. 

Social Assessment 

In most biodigester developments, designers and administrators pay enough attention to the construction process, however, if effective final users training, follow up management, operations, daily maintenance and repair work are not well designed and carried out, it will result in inadequate technical services and support. This can result in the paradoxical situation of progress with the biodigester’s construction because of the school being unable to actually benefit once projects are completed.

Health improvement

A biodigester development improves the health of community members by providing proper sanitary conditions by efficient use of human and animal waste into the biodigester, reduction of indoor air pollution by using biogas for cooking as well as water quality and sanitation by handling human and animal waste as key elements to improve the health of the community

Water quality and sanitation

When there is a lack of efficient human and animal waste disposal, water bodies can easily be contaminated. This can bring negative consequences to the community. For example, many large agricultural farms in Kenya, water their crops with contaminated water, which can cause an important number of diseases such as, diarrhoea, cholera, typhoid, and amoebiasis among the consumers of these crops. Children die of diarrhoeal diseases due to inadequate sanitation facilities. Provision of safer water, sanitation and hygiene practices could prevent about 90 per cent of those deaths”.

Economic Analysis

Economic benefits are calculated taking into account the social and environmental benefits discussed previously as well as the capital cost, operations,  maintenance costs and time-saving.