Waste Treatment Generated during Silicon Based Solar Cells Production Towering a Complete LCA Processing

  1. Cendagorta, M.
  2. Friend, M.
  3. Guerrero-Lemus, R.
  4. Hernandez-Rodriguez, C.
  5. González-Pérez, S.
  6. Jarabo, F.
  7. Llarena, E.
  8. Montes, C.
  9. Linares, A.
  10. Segredo-Morales, E.
  11. González-Díaz, B.
Actas:
29th European Photovoltaic Solar Energy Conference and Exhibition

Editorial: WIP

ISBN: 3-936338-34-5

Año de publicación: 2014

Páginas: 3409-3414

Tipo: Aportación congreso

DOI: 10.4229/EUPVSEC20142014-5DV.3.42 GOOGLE SCHOLAR lock_openAcceso abierto editor

Resumen

In this work, the multiple liquid and gas waste stream products derived from the fabrication of monoand multi-crystalline silicon based solar cells in a standard 120 MW/year production line are evaluated. The data are obtained from the Ecoinvent database, and some additional assumptions are made in relation to the current state of the technology and costs of the consumables. The aim of the work is to reach zero environmental impact for the different waste streams chemically treating all of them to recover consumables for their reuse or transferring the products to other industrial activities. In this regard, six waste streams have been identified: (i) two liquid waste streams of HF/H2SiF6/HNO3 and NH3; (ii) three gasses waste streams of NH3/SiH4, HCl, and H2/HF//KOH/HNO3/NOx/SiF4; and (iii) a solid waste stream of KNO3. The purification of the water inside the liquid lines is analyzed for being reused inside the production line. Also, some purification processes allow the recovering of gases used in the fabrication steps. The new products derived from the chemical treating are NaNO3, CaF2, N2SiF6, NH4Cl, and they are attractive for being transferred to the industry as fertilizers and electrical insulators for transformers. Some important sensitive curves related to variations in consumable costs and demands are also included.