Objectives and results

Our objectives

The main objective of this proposal is to reduce the concentration of nitrates in the integral water cycle, implementing an integrated, innovative, simple, economical, sustainable and transferable system, based on the use of an adsorption bed manufactured with Active silica from the ash produced by the controlled burning of rice straw.

Expected Results

1. To construct and validate a prototype (I) for the purification of water with a high nitrate content by means of an adsorption bed of active silica, obtained from the controlled incineration of rice straw in a fluidised bed boiler of the Spouted Bed type adapted for this purpose.
2. Develop a pedagogical guide to promote the reduction of at least 20% in the use of nitrogen fertilisers among farmers.
3. To reduce by at least 30% the nitrate concentration of an effluent of 130L/day of water in:
     1. in direct well water from 65-75 ppm below 50 ppm in drinking water to facilitate compliance with the European Nitrates Directive 91/676/EEC;
       2. in the reject effluent from the reverse osmosis plant, 120-180 ppm.



Validate a PROTOTYPE to obtain active silica from the controlled incineration of rice straw to obtain silica-rich ash.

To obtain the objetives:

Validate a prototype for the preparation and implementation of active silica beds to reduce the concentration of nitrates in the water cycle by acting:
1. On the headwater (from groundwater) and rejection in an osmosis plant.
2. On well water for human consumption in small municipalities to reduce the nitrate concentration below 50 ppm, without the use of an osmosis plant.

In addition, we aim to:


a comprehensive system of awareness among farmers to promote the use of fertilizers with low environmental impact.

Incardinate ...

the project in the general policies of the EU and promote a plan of political intervention that promotes specific lines of financing in the Operational Programs

assess ...

the impact of the project in environmental, social and economic terms.

boost ...

the sustainability, replicability, transferability and transnationality of the proposed strategies and innovations in the EU as a whole.

Spread and publicize ...

the results obtained for users, clients, territorial agents and society in general.

Results Obtained

  • A prototype adsorption bed with active silica has been constructed and validated, which is capable of retaining an average of 23.63% of nitrate content in water flows of up to 26,000 litres/day.
  • The process for obtaining the active silica used in the adsorption beds has been granted two patents: Spanish Patent No. E2727673 B2 / European Patent No. EP3929161A1.
  • The economic and environmental viability of using slow-release nitrogen fertilisers in citrus, persimmon and rice fields has been demonstrated.
  • Educational guides (in Spanish, English, Italian and Dutch) have been produced for farmers, aimed at reducing the use of nitrogen fertilisers. 
  • A MOOC course on fertilisation in Nitrate Vulnerable Zones has been created.


You can consult and download, documentation elaborated in the process of implementation of the expected objectives, as well as final documentation of the objectives achieved in the LIFE LIBERNITRATE project:


.- Layman Report (english version)

.- MOOC course on fertilisation of nitrate-vulnerable areas

.- Didatic guide for the reduction of nitrogen fertilisers

.- Report on the development of industrial protection rights

.- Information and comunication material: