Integral Management of Organic Matter


Oil Palm

The African Oil Palm is the crop with the highest oil yield per hectare. This explains why the Oil Palm industry is growing significantly around the world to provide fats and oils needed mostly by the food industry.
The sector is currently under pressure to ensure more sustainability to its practices. BIOTEC is part of this dynamic, providing relevant and tailor-made solutions at environmental, agricultural, energy and social levels.

Each palm oil mill generates liquid by-products known as Palm Oil Mill Effluent (POME). This effluent holds large amounts of organic matter, equivalent to those generated by densely populated cities; by the way they pose a significant risk of environmental contamination.

On the other hand, these by-products have a high fertiliser value and energy potential. The bio-digestion of the “POME” in bio-digesters of the BIOTEC RAC model generates an average of 15 m3 of CH4 and 60 kWh per ton of fruit (FFB).

EFB fertilizer value is around 3 US$ per T FFB and POME fertilizer value is between 4 and 5 US$/T FFB.

Under the BIOTEC approach, there is no reason to send raw or treated POME to the river. These nutrients and this organic matter must go back to the soils.

BIOTEC developed the concept of the Zero Discharge Milling (ZDM) and developed several technologies to achieve it:

  • Open ponds and open biodigesters + liquid fertilization.
  • Biodigestion + liquid fertilization.
  • Bio-evapo-drying to produce a powdered biofertilizer.
  • Co composting with EFB (4 meters high heap / lateral turning / no roof requirement).
2nd     POME biodigester in the world

(Palmeras del Llano, Colombia, 1988)



1st      POME ferti-irrigation system using micro-sprinkler

(Palmar Santa Elena, Colombia 1992)



1st      Covered lagoon Biodigester for POME

(Palmeiras, Colombia, 1999)



1st      CDM Project (Gold Standard) for POME in the world

(Eecopalsa, Honduras, 2007)



1st    Dosed and monitored POME fertigation system (FORLIM)

(Exportadora del Atlántico, Honduras, 2010)



1st      Combined POME and biodiesel plant effluents biodigester

(MANUELITA, Colombia, 2014)



1st     POME bio-evapo-drying (pilot) plant.

(Pilot plant, Faridabad , India, 2018)


BIOTEC also implements the SSP technology of raw POME to animal feed factory when sufficient steam is locally available for the evapo-drying.


Cane is the most important source of sugar in the world and, together with corn, the most important source of bio-ethanol.

While cane production is approaching 50 tons of dry matter per hectare per year, sugar and bioethanol production account together for 15 tons. The difference between these two numbers are the by-products (leaves, tops, bagasse, sludge, wastewater and vinasses) which contain the nutrients exported by the crop.

Bagasse is an attractive biomass used as source of steam and electricity and in some cases as raw material for paper. Vinasses represent an environmental (pollution) and agricultural challenge (potassium concentration + salinization). Sugar mud (filter cake) and vinasses represent the major amount of nutrients. Sugar mud, raw or composted, is usually spread on the crops. Good management of these by-products is an opportunity for agribusiness to obtain added-value for its core business and ensure long-term sustainability.

BIOTEC brings knowledge and experience in the handling of sugar mud, wastewater and vinasses, like:

  • Wastewater treatment and valorization
  • Sugar mud composting
  • Vinasses and sugarmud co-composting
  • Sugar mud biodigestion
  • Vinasses biodigestion
  • Vinasses + sugarmud co-digestion
  • Vinasses bio-evapo-drying (up to powder)
  • Vinasses + sugarmud bio-evapo-drying (up to powder)

Finally, BIOTEC promotes the organic fertilisation of sugarcane plantations with: filter mud cake, compost, purged sludge of biodigesters and raw or treated vinasses. For the sugarcane industry, these technologies represent additional business opportunities. This set of solutions ensures a sustainable business management.


  • Zero Discharge Milling (ZDM).
  • Renewable Natural Gas (RNG) production.
  • Powdered biofertilizer production for cane fertilization or rather for sale to fertilizer companies (to avoid potassium concentration in the nearby land).


Currently, consumers increasingly worry about what they consume, and are aware of the importance of a healthy lifestyle that also respects the environment. It generates a significant increase of the consumption of fruits and derivatives such as citrus fruit juices. As the production increases to meet this demand, so does the generation of solid by-products (pulps and peels) and liquids (effluents). 

Acidic effluents from the process of lemon and orange, as well as the husks, skins and seeds are used to generate biogas to meet steam and/or electricity demand replacing fossil fuels. Additionally, the treated effluents / biodigestate are recycled to fertilize the plantation.

With the experience of BIOTEC, these by-products (usually considered as waste) are converted in raw materials for renewable energy and fertilization.

1st Large-scale digester in the world for lemon effluent treatment

  • Citrusvil, Argentina, 2009:

11,000 m3 of effluent/day x 11,000 ppm COD
Biogas generation for boiler of 6 and 10 T of steam per hour + ferti-irrigation 600 ha. 

  • Citrusvil, Argentina, 2014:

Implementation of an additional 10.000 m3 RAFAC biodigester (Up-flow-contact model).

  • Citrusvil, Argentina 2018-2019:

R&D on biogas generation during inter-harvest months with husks, skins and lemon seeds. Engineering of this “solid waste to gas” project.

    • R&D on biogas generation during inter-harvest months with husks, skins and lemon seeds.
    • Engineering of this “solid waste to gas” project.


BIOTEC offers customised solutions for many types of effluents and organic waste.

BIOTEC has a long track record with UASB biogas plants for these effluents, with concrete or metallic reactors (welded or bolted). In all the cases, the main objective remains the same: ZERO DISCHARGE, with effluents and by-products valorization through animal feed, liquid or solid biofertilizer and biogas.

Such as:


Energy Crops

Major activity of BIOTEC is to transform the agro-industrial by-products into main raw materials, fertilizer and energy (biogas), adapting to the Tropic the European experience in biodigestion. However, the world needs much more renewable energy than by-products and agro-industrial effluents can produce. Many regions of the world which do not have any electricity, or which only have diesel power plants, are coincidentally located in tropical areas, with high availability of land and few opportunities to market agricultural products. For this reason, BIOTEC has decided to focus its efforts on the production of energy (biogas) from tropical grasses and forages (“energy” crops for the Tropics and for the “Southern Cone” of Latin America).

The generation of biogas from biomass, for later use in power plants, differs completely from the combustion of biomass in boilers for generation of steam and electricity with steam turbines. This second option, relatively common in the world, takes advantage of the Rankin cycle, and is limited by two key constraints:

  1. It burns the organic matter required by tropicals oils (as well as N and S).
  2. Large power plants are required (over 40 MW) to have acceptable electrical performance, economies of scale and a minimum return on investment.

Compared with diesel power plants or LPG supply, the biogas generation with grasses and forage can be profitable at medium and large scale (500 kW to 5 MW). This technology recycles all the fermented organic matter (digestate = organic fertiliser) to the soils, achieving the highest yields without the necessity of chemical fertilization.

The generation of biogas and electricity from grasses and forages is not a new concept: it is the energy source of most of the biogas produced today in Europe (in around 10.000 farms). Farmers initially added maize silage and grass to their manure; nowadays they process much more silage than manure.

BIOTEC put all its R&D capacity to adapt this European concept to the Tropics with the support of SAUTER, its German technology partner (

This concept allows:

  • Achieving rural electrification in remote areas, based on renewable energy.
  • Generating energy at competitive prices: gas and electricity production costs are already lower than their diesel or LPG equivalent (average 2019 prices).
  • Producing at the same time electricity and gas for household use.
  • Social development in tropical rural areas.

Our scope: