A proposed index to assess quality of waters from desalination plants

Francisco P De S Antas,Nildo Da S Dias,Jair J R De Freitas,André M De Oliveira,Osvaldo N De Sousa Neto,Alexandre De O Lima

doi:10.1590/1807-1929/agriambi.v22n10p667-672

Abstract

ABSTRACT Reverse osmosis is the technology commonly used to produce fresh water from brackish groundwater. Due to the reject brine generated in desalination plants by reverse osmosis, vulnerability assessment to define critical areas to monitor waters from desalination has been an important tool for delineating the monitoring networks required for surveillance of potential salinization sites. The objective of this study was to assess the quality of waters sampled in desalination plants by a quality index, which provides a relative assessment of water vulnerability to potential salinization. The present study proposes an index to assess the quality of waters from desalination plants initially using the chemical parameters electrical conductivity, sodium adsorption ratio, Mg2+/Ca2+ ratio, and the ions sodium, chloride and bicarbonate. The index to assess quality of waters from desalination plants showed good performance and can include additional parameters referring to the soil and crop exploited. High values of the relative index of quality of waters from desalination plants are considered as possible indicators of risk of soil salinization and groundwater contamination. The highest level of land use impact on the quality of waters from desalination plants was found in reject brine samples followed by well water samples.

Highlights

IntroductionMaterial and MethodsIn the semi-arid region, due to the irregular rainfall regime, agricultural production is limited because the low rainfall levels do not meet crop water needs; the adoption of irrigation becomes necessary (Andrade et al, 2012; Silva et al, 2014)
Material and MethodsIn the semi-arid region, due to the irregular rainfall regime, agricultural production is limited because the low rainfall levels do not meet crop water needs; the adoption of irrigation becomes necessary (Andrade et al, 2012; Silva et al, 2014)
Applying the technology of desalination by reverse osmosis allows the utilization of saline and brackish waters, which can be used for human consumption (Dias et al, 2010), despite the production of reject brine as a limiting factor (Bush et al, 2016; Khanzadaa et al, 2017)

Summary

Introduction

Material and MethodsIn the semi-arid region, due to the irregular rainfall regime, agricultural production is limited because the low rainfall levels do not meet crop water needs; the adoption of irrigation becomes necessary (Andrade et al, 2012; Silva et al, 2014). Tyagi et al (2013) claim that quality indices aim to provide a single value for the quality of a water source, because it reduces the number of parameters in a simple expression, resulting in easy interpretation of water quality monitoring data. Despite this advantage, no index has been universally accepted and they need to be adapted to the local specific conditions (Rodrigues et al, 2007)

Objectives

Results

Conclusion