6.5.11 Substrate Composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
6.5.12 Environmental Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
6.6 Applications in Hydrocarbon-Rich Wastewater Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
6.7 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
Abstract Petroleum industry alone is regulating a major part of the world economy.
Everyday million litres of hydrocarbon-rich wastewater is generated from oil refineries, which is one of the major drawbacks of oil industries. Oily wastewater is
carcinogenic for humans and animals, and oils can cause ground seepage and can
reduce oxygen solubility in water which further affects the marine ecosystems.
Among the treatment processes, biological techniques are more suitable to provide
eco-friendly results.
The current research trends in hydrocarbon-rich wastewater treatment suggest
aerobic granulation as one of the modern biological remedies for oily wastewater.
Aerobic granules are densely packed microbial aggregates containing millions of
different bacteria. They offer cost-effective and simultaneous degradation of carbon,
nitrogen, phosphorus and hydrocarbons in a single reactor system. This technology
has been successfully employed in treating petrochemical, coal gasification and palm
oil meal effluents. About 1–3.5 mm-sized aerobic granules containing extracellular
polymeric substances of 200–300 mg/g volatile suspended solids with 30–70 m/h
settling velocity provided almost 90% chemical oxygen demand and 70–90% oil
removal while treating 5.6–320 mg/L of hydrocarbon containing wastewater. Above
5 g/L of granule biomass and below 50 mL/g sludge volume index indicated granule
stability and compactness throughout oil removal process. This chapter focuses on
the mechanisms, effecting factors, characteristics and characterization techniques of
aerobic granulation with its detailed application in hydrocarbon-rich wastewater
treatment.
Keywords Hydrocarbon-rich wastewater · Poor biodegradability · Aerobic granular
reactor · Granulation mechanism · Characterization · Parameters · Factors · Oil
degradation
6.1 Introduction
Hydrocarbon-rich wastewater is generated from crude oil reservoirs, palm oil meals,
petroleum refineries and fuel manufacturing companies. Oily wastewater can impose
hazardous effects on water bodies, aquatic lives, crop production and also on animal
and human health (Biswal et al. 2009). Residual crude oil can cause groundwater
pollution (Novaković et al. 2012) and ecotoxicity of polyaromatic hydrocarbons
were also investigated by researchers (Manzetti 2012). According to the standards
for Effluent Discharge Regulations of Environment Protection Act 2002, the permissible limit of oil and grease in effluent is 10 mg/L and according to the Indian
174
S. Ghosh and S. Chakraborty
6.5.12 Environmental Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
6.6 Applications in Hydrocarbon-Rich Wastewater Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
6.7 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
Abstract Petroleum industry alone is regulating a major part of the world economy.
Everyday million litres of hydrocarbon-rich wastewater is generated from oil refineries, which is one of the major drawbacks of oil industries. Oily wastewater is
carcinogenic for humans and animals, and oils can cause ground seepage and can
reduce oxygen solubility in water which further affects the marine ecosystems.
Among the treatment processes, biological techniques are more suitable to provide
eco-friendly results.
The current research trends in hydrocarbon-rich wastewater treatment suggest
aerobic granulation as one of the modern biological remedies for oily wastewater.
Aerobic granules are densely packed microbial aggregates containing millions of
different bacteria. They offer cost-effective and simultaneous degradation of carbon,
nitrogen, phosphorus and hydrocarbons in a single reactor system. This technology
has been successfully employed in treating petrochemical, coal gasification and palm
oil meal effluents. About 1–3.5 mm-sized aerobic granules containing extracellular
polymeric substances of 200–300 mg/g volatile suspended solids with 30–70 m/h
settling velocity provided almost 90% chemical oxygen demand and 70–90% oil
removal while treating 5.6–320 mg/L of hydrocarbon containing wastewater. Above
5 g/L of granule biomass and below 50 mL/g sludge volume index indicated granule
stability and compactness throughout oil removal process. This chapter focuses on
the mechanisms, effecting factors, characteristics and characterization techniques of
aerobic granulation with its detailed application in hydrocarbon-rich wastewater
treatment.
Keywords Hydrocarbon-rich wastewater · Poor biodegradability · Aerobic granular
reactor · Granulation mechanism · Characterization · Parameters · Factors · Oil
degradation
6.1 Introduction
Hydrocarbon-rich wastewater is generated from crude oil reservoirs, palm oil meals,
petroleum refineries and fuel manufacturing companies. Oily wastewater can impose
hazardous effects on water bodies, aquatic lives, crop production and also on animal
and human health (Biswal et al. 2009). Residual crude oil can cause groundwater
pollution (Novaković et al. 2012) and ecotoxicity of polyaromatic hydrocarbons
were also investigated by researchers (Manzetti 2012). According to the standards
for Effluent Discharge Regulations of Environment Protection Act 2002, the permissible limit of oil and grease in effluent is 10 mg/L and according to the Indian
174
S. Ghosh and S. Chakraborty