Energy saving in the chemical industry - ERCROS

Showcase project. Investment

Project description

Replacement of mercury technology in the production of chlorine and potash by a technology based on membrane electrolysis in the factory which Ercros SA has in Sabiñánigo (Huesca).

Technical data

Installation of two membrane electrolysers with a maximum production of 3.9 tonnes chlorine/hour. Ercros has this equipment available at no cost as a consequence of the research being carried out jointly with Asahi Kasei.

Incorporation of secondary purification in the brine circuit.

Reconditioning of the chlorine circuit.

Installation of equipment for potash concentration to obtain commercial potash at 50%.

Financial and energy data

Completed in 2010, the project has achieved average energy savings of 6,043 MWh/year. The financial saving through reduction in energy consumption and reduction of treatments, maintenance etc reaches 2.6 million euros/year.

IDAE investment and expected income

The investment made by the IDAE, through Commercial Financing and a contract of service leasing has been 18.42 million euros. 

The return on investment for the Institute is estimated at 26.58 million euros.


The substitution of mercury cells by membrane cells can be translated to the manufacture of chlorine and caustic soda. The project will therefore be replicable in INIVYN ESPAÑA (Martorell), SOLVAY QUIMICA (Torrelavega), ELNOSA (Lorizán factory), ERCROS S.A. (Vilaseca factory) and Electroquímica Onubense (Palos de la Frontera).