Environmental performance of a full-scale wastewater treatment plant applying Life Cycle Assessment

Thaís Andrade De Sampaio Lopes,Asher Kiperstok,Luciano Matos Queiroz

doi:10.4136/ambi-agua.2216

Thaís Andrade De Sampaio Lopes, Asher Kiperstok + Show 1 more

Open Access

https://doi.org/10.4136/ambi-agua.2216

Copy DOI

Abstract

Life Cycle Assessment (LCA) was applied to estimate and analyze the environmental impacts from the construction and operation phases of a full-scale wastewater treatment plant (WWTP) located in the municipality of Lauro de Freitas, Bahia, Brazil. The WWTP process consists of the association of an Upflow Anaerobic Sludge Blanket (UASB) reactor followed by four constructed wetlands (CWL) and a disinfection step. The functional unit was defined as one cubic meter of treated effluent during the useful life of this WWTP (20 years). The LCA was carried out using SimaPro® software and the Centre of Environmental Science (CML) assessment method. The environmental impacts during construction phase were mainly from the wooden forms for concrete and the use of reinforcing steel. During the operation phase, the chlorine used as effluent disinfectant caused the greatest impacts in the abiotic depletion and acidification categories. Macronutrient concentrations present in the treated effluent and the methane generated also caused significant environmental impacts during the WWTP’s useful life. The results obtained highlight the importance of the application of a methodology like LCA to assist in decision-making with regard to the implementation, construction and operation of a WWTP.

Highlights

Wastewater treatment plants (WWTP) are designed to protect public health and minimize the environmental impacts of discharging untreated wastewater into natural aquatic systems
Consists of an Upflow Anaerobic Sludge Blanket (UASB) reactor followed by four constructed wetlands (CWL) and a disinfection step with the application of sodium hypochlorite solution (NaOCl) in a contact basin
Life Cycle Assessment (LCA) applied to a wastewater treatment plant (WWTP), a process comprised of anaerobic digestion in a UASB reactor followed by four constructed wetlands and a final effluent disinfection step, allowed concluding that:

Summary

Introduction

Wastewater treatment plants (WWTP) are designed to protect public health and minimize the environmental impacts of discharging untreated wastewater into natural aquatic systems. Different WWTP have distinct performances and generate direct environmental impacts like any process that uses natural resources. The goals set for a specific WWTP need to move beyond the protection of human health and surface waters to include minimizing the loss of scarce resources, reducing the energy, water use and waste generation, besides enabling the recycling of water and macronutrients. Using a whole-process approach and addressing all relevant environmental impacts over the WWTP’s useful life, the LCA allows an assessment that goes beyond the usual trade-off between treatment efficiency and effluent quality standards (Corominas et al, 2013; Risch et al, 2014; Zang et al, 2015)

Objectives

Methods

Results

Conclusion