Poster (Scientific congresses and symposiums)
Environmental Product Declaration of purified and defluorinated phosphoric acid – difficulties and limitations of the methodology
Belboom, Sandra; Szöcs, Carl; Léonard, Angélique
201319th SETAC Europe LCA Case Studies Symposium
 

Files


Full Text
Poster SBelboom_Rome_Prayon_AL.pdf
Publisher postprint (1.2 MB)
Request a copy

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
Environmental product declaration; Life Cycle Assessment; Phosphoric acid; Limitations
Abstract :
[en] The awareness of environment and the development of environmental product declarations (EPDs) are increasing through years. EPD becomes a need for producers in both B to B and B to C relations. EPD elaboration process is not without difficulties. Such a declaration requires a considerable amount of time and information, a full comprehension of the applied methodology but it also causes confidentiality problems. All these difficulties can lead to the use of simpler tools, as Carbon Footprint, which only focuses on a single impact and misses a part of the message. This case study is based on the production of phosphoric acid in Belgium using PCR for inorganic chemicals. It takes into account the use of raw materials as phosphate rocks or chemicals, their transportation to site and the manufacturing of defluorinated and purified phosphoric acid. This process also requires steam, electricity, demineralised water and sulphuric acid. These inputs are produced on site and their modelling is taken into account in this study. The first step of this process is the production of weak phosphoric acid with transformation of phosphate rocks into 30% phosphoric acid using sulphuric acid attack. The particularity of this process is the production, in this company, of a recoverable coproduct, called gypsum. The amount of this product is about 1.6 t per t of weak acid. A stoichiometric relation connects both products and is used as allocation factor, as recommended by the PCR. Through next concentration steps, fluosilicic acid is produced, also linked to the production of phosphoric acid by a stoichiometric relation. For facilities production plant, repartition of impact between coproducts is not so easy. As mentioned before, the production of steam, electricity, demineralised water and sulphuric acid are performed on site. Sulphuric acid is produced by the combustion of liquid sulphur provided by oil refineries. Two different units produce both sulphuric acid and steam through the combustion of liquid sulphur but only one of them transforms a part of steam into electricity. Repartition of impact between sulphuric acid and steam can be achieved using a physical relation based on thermodynamic values which can be transformed into mass relation. For repartition between electricity, steam and sulphuric acid, the main difficulty is that electricity does not have a weight and a transformation into steam shall be achieved to use the same relationship that previously. This way of allocating is not very obvious for producers, even if it is the one recommended by the PCR. As electricity and steam are coproduced, an energetic allocation is also relevant and gives completely opposite results for repartition of impact of each product. In that case, sulphuric acid impact achieves a non-negligible part of the impact which modifies greatly results of phosphoric acid production. This is a problem when you know that environmental product declarations are used to compare products on environmental criteria, using mainly values of climate change or energy impacts. Producers are then reticent to publish such a value which can lead to a loss of customer confidence, even more when they occupy a leading position on the market and taking into account that a comparison with other producers is quite impossible. More specific guidelines should be set to indicate the best way to perform an environmental product declaration in specific fields using a specific way of allocation.
Disciplines :
Energy
Chemical engineering
Author, co-author :
Belboom, Sandra ;  Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Procédés et développement durable
Szöcs, Carl;  Prayon sa
Léonard, Angélique  ;  Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Procédés et développement durable
Language :
English
Title :
Environmental Product Declaration of purified and defluorinated phosphoric acid – difficulties and limitations of the methodology
Publication date :
November 2013
Event name :
19th SETAC Europe LCA Case Studies Symposium
Event organizer :
SETAC
Event place :
Roma, Italy
Event date :
11 - 13 novembre 2013
Audience :
International
Available on ORBi :
since 04 December 2013

Statistics


Number of views
163 (5 by ULiège)
Number of downloads
1 (1 by ULiège)

Bibliography


Similar publications



Contact ORBi