Sodium inhibition and sulphate reduction in the anaerobic treatment of mussel processing wastewaters

Abstract

An anaerobic filter treating high saline wastewaters from a sea food processing industry was subjected to sodium and sulphate shocks. Sodium concentrations ranging from 5 to 12 g dm−3 had no significant influence on the methane production rate, with maximum value of 15 kg COD CH 4 m−3 day−1. The sulphate‐reducing capacity of the filter was estimated at 2.2 kg SO42‐ m−3 day−1. When using propionic or acetic acid as substrates, the sulphate‐reducing activities were 0.021 and 0.006 g SO42‐ g−1 VSS day−1 respectively. Determination of the methanogenic activity of the sludges indicated that sodium concentrations of 14 g dm−3 caused a 50% inhibition of the methanogenic activity from the anaerobic filter. However, when using the anaerobic filter effluent as the assay medium, the sodium concentration giving the same percent inhibition was 17.7 g dm−3, indicating a beneficial effect probably due to the antagonism caused by the presence of other sea salts. The sludge showed a higher tolerance to sodium toxicity than that reported in previous literature, which can be explained as a consequence of sludge adaptation.

Effect of fluctuations in salinity on anaerobic biomass and production of soluble microbial products (SMPs)

“…This shows that the rate of biodegradation by the propionic utilizers was significantly decreased in the presence of NaCl. This finding is in agreement with Soto et al (1993) who found that an increase in the sodium concentration from 5 to 12 gNa + l -1 resulted in an increase in the propionate to acetate ratio from 0.7 to 1. However, Feijoo et al (1995) using granular non-adapted biomass found that nbutyrate utilisers were the most sensitive group of bacteria.…”

A comprehensive review on operating parameters and different pretreatment methodologies for anaerobic digestion of municipal solid waste

“…As a result, the specific surface area is increased, the substrates are easily accessible to anaerobic microbes [83,106,107]. [83,109] 7 Lignocellulosic biomass Acid pretreatment is an expensive process due to high cost of acids and the additional cost for neutralizing the acidic conditions prior to the AD process [106,112,113] 8 Waste water Sodium is more toxic to propionic acid utilizing bacteria as compared to other VFA degrading bacteria [114] 9 Sludge…”

Organic Fraction of Municipal Solid Waste: Overview of Treatment Methodologies to Enhance Anaerobic Biodegradability

“…Kim et al (2000) contemplated hindrance because of the sodium particle dose on the AD bioreactor running on thermophilic zone of FW and stated that sodium at a concentration of >5 g/L brought about decrease in biogas generation. Sodium is more lethal to propionic acid utilizing microorganisms when contrasted with other VFA debasing microorganisms in the AD system (Soto et al, 1993). The inhibitory effect of potassium begins at the level of 400 mg/L.…”