Technical Aspects and Cost Estimations for Anaerobic Systems Treating Vinasse and Brewery/Soft Drink Wastewaters

Abstract

Anaerobic digestion of industrial and domestic wastewaters is an effective way of alleviating pollution problems. The treatment of vinasse, a residue of ethanol fermentation, and brewery/soft drink wastewaters was investigated by IPT for several years. This paper presents data and discusses the technical and economical feasibility of treating these wastewaters using UASB reactors. With vinasse, it is possible to operate industrial plants with organic loading rates exceeding 15 kg COD m−3 day−l, removing 95% of the initial BOD. The produced gas can be used as a substitute for diesel oil in vehicles and also to produce steam, replacing bagasse. The pay-back period of the capital investment is estimated at around 4 to 5 years. For brewery/soft drink wastewaters, it is possible to operate UASB reactors with a HRT of 6 hours, removing more than 90% of the initial BOD. The reactor showed a good capacity to handle temperature shocks. Capital investments for both cases are presented in terms of total investment per kg of COD and m3 of reactor installed.

Relationships between chemical oxygen demand (COD) components and toxicity in a sequential anaerobic baffled reactor/aerobic completely stirred reactor system treating Kemicetine

“…In conclusion, the total estimated operational cost was 3.1 USD for treating 30 m 3 /day pharmaceutical industrial wastewaters containing 125 mg/l Kemicetine with removal efficiencies higher than 95%. This cost was very competitive when considering the operational cost of treated vinasse wastewater (a residue of ethanol fermentation) (1000 USD for 500 m 3 /day)) [64]. The operational cost was very similar to that of Sreekanth et al [57] and Sreekanth et al [65] treating synthetic wastewater containing phenolic compounds and drug anatibiotic wastwater in the hybrid upflow anaerobic sludge blanket reactors (2.6 USD for a flow rate of 50 m 3 /day).…”

Anaerobic digestion of vinasse from sugarcane ethanol production in Brazil: Challenges and perspectives

“…Regardless of its origin, the main organic compounds present in sugarcane vinasse reported in the literature consist of organic acids (mainly lactate and acetate), as well as alcohols (mainly glycerol and ethanol) and a minor amount of carbohydrates [14,[54][55][56][57]. Table 3 compiles studies in which vinasse characterization was performed, presenting the main parameters that define its composition according to the fermentation feedstock [47,48,[58][59][60][61][62].…”

“…The simple design and low capital/operational costs have made such technology a ubiquitous starting point for the treatment of wastewaters with a high organic load [84]. In the case of sugarcane vinasse, business processes were developed in the late nineteenth century but found no interest from the sugarcane sector due to the low economic viability of electricity generation from biogas [58,60,85]. This technological possibility is now being reconsidered due to the need to reduce the organic load of the effluent to the soil while maintaining the nutrient and mineral content, as well as to the interest in optimizing the energy balance of sugarcane biorefineries [82][83][84].…”

Bioenergy from stillage anaerobic digestion to enhance the energy balance ratio of ethanol production

“…Table 2 depicts the energetic potential for stillages from the three different feedstocks evaluated in this paper. Particularly, the energetic potential of sugarcane stillage was also calculated based on data regarding the biogas production in pilot-to-large scale (volume > 10 m 3 ) anaerobic reactors reported elsewhere (Costa et al, 1986;Craveiro et al, 1986;Bories et al, 1988;Karhadkar et al, 1990;Souza et al, 1992;Driessen et al, 1994). In this case, the term effective energetic potential was used, as the calculations were based on real operating scenarios.…”