Life cycle assessment of refurbishment scenarios to confined tank structures at a waste water treatment plant

EasyChair Preprint no. 4233

Abstract

Sewers and confined tanks in waste water treatment plants often suffer from biogenic corrosion in their areal zones. This biogenic corrosion occurs because of the transformation of the sulfates present in domestic waste water into hydrogen sulfide gas and then subsequently into sulfuric acid by different strains of bacteria.

The sulfuric acid attacks all types of mineral substrate severely. Traditionally, concrete repair systems with reactive resins are used, but these require defect-free conditions and application, which are often impossible to achieve in such difficult environments.

In the last 20 years, 100% calcium aluminate based mortars (cement & aggregates) have been used to successfully renovate these structures. The unique feature of this technology is its ability to block the transformation of hydrogen sulfide into sulfuric acid, and this has already been explored in various published papers.

The paper will show a Life Cycle Assessment (LCA of three different refurbishment scenarios in confined structures – one using a traditional Portland cement based repair mortar, one combining this cement repair mortar with a reactive protective coating, and one using 100% calcium aluminate based repair mortar technology.

In order to evaluate the sustainability and potential environmental impact of each of the three scenarios, the Life Cycle Assessments (LCA) were performed, which included Cumulative Energy Demand (CED), Global Warning Potential (GWP) and Photochemical Ozone Creation Potential (POCP). The results are compared and analyzed in this paper. Comparison in relation to extending the structural service life also shows how innovative systems can give advantages to designers and contractors for the benefit of their customers.

Keyphrases: Biogenic corrosion, Calcium Aluminate Mortar, Concrete protection, Sewer Refurbishment, Waste Water Treatment Plants

@Booklet{EasyChair:4233,
  author = {Michel Donadio and Catrina Heider and Zeno Dan},
  title = {Life cycle assessment of refurbishment scenarios to confined tank structures at a waste water treatment plant},
  howpublished = {EasyChair Preprint no. 4233},

  year = {EasyChair, 2020}}