Direct and continuous dissolved CO2 monitoring in shallow raceway systems: From laboratory to commercial-scale applications

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Maria Teresa Borges (Author) FCUP; Jorge O Domingues (Author) Other; Joao M Jesus (Author) Other; Carlos M Pereira (Author) FCUP

Journal

Title: Aquacultural Engineering

Vol. 49

Pages: 10-17

ISSN: 0144-8609

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 5 Citations

Scopus - 6 Citations

Scientific classification

FOS: Agrarian Sciences > Agricultural biotechnology

Other information

Authenticus ID: P-002-8GC

DOI: 10.1016/j.aquaeng.2012.01.003

Abstract (EN): Direct and continuous measurement of dissolved CO2 (dCO(2)) is crucial for intensive aquaculture, especially in shallow raceway systems (SRS). In this work the performance of a portable dissolved CO2 probe analyzer was tested for the effects of different aqueous solutions, pure oxygen injection and agitation. Laboratory results showed significant (p < 0.05) solution effects on probe performance for low (10-20 mg L-1) and high (30-50 mg L-1) dCO(2) concentrations. Globally performance was better in deionized water, followed by marine fish farm water and artificial seawater. Accuracy and response time were the parameters most affected by the type of solution tested. Linearity was always observed (R-2 = 0.995-0.999). The probe was sensitive to 1 mg L-1 dCO(2) increments for concentrations <6 mg L-1 in artificial seawater. Pure oxygen injection did not affect probe readouts, and agitation was needed for better accuracy and response time. In real marine SRS with tanks in series dCO(2) dynamics was revealed using the probe coupled to a developed flow cell. A prototype SRS was built and used to study dCO(2) dynamics without endangering cultivated fish. Generally, results obtained indicate that the probe tested although precise, is better suited for discrete, single-point dCO(2) monitoring, being a limited resource for the special needs of shallow raceway systems. As SRS represent a paradigm change in aquaculture, new water quality monitoring strategies and instrumentation are needed, especially for dCO(2). Fiber optic sensors can be a solution for continuous, multipoint monitoring, thus contributing to the understanding of water quality dynamics in hyperintensive aquaculture systems.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8