Molasses Alcohol Wastewater Research Articles

Improving the efficiency of anaerobic digestion of Molasses alcohol wastewater using Cassava alcohol wastewater as a mixed feedstock

Cassava alcohol wastewater (CAW) was utilized as a mixed feedstock to explore whether the addition of CAW could improve the anaerobic digestion of Molasses alcohol wastewater (MAW). The result showed that the rate of removal of the soluble chemical oxygen demand in the M treatment mixed with CAW was 70.13 ± 0.16%, which was significantly higher than that of the C treatment (only MAW), which was 61.23 ± 0.36%. Co-digestion in the M treatment resulted in higher methane production, achieving 23.89% increase in methane yield compared to C treatment. The addition of CAW helps to alleviate the accumulation of volatile fatty acids (397.06 ± 141.82 mg·L-1), enhance the stability of system and promote the establishment of stable and active microbial communities. Microbial community structure analysis indicated that hydrolytic bacteria such as Bacteroidetes, Firmicutes, and Proteobacteria, and acetoclastic methanogens, including Methanosaeta and Methanosarcina were more abundant in the co-digests.

Decolorization of molasses alcohol wastewater by thermophilic hydrolase with practical application value

The aim of this work was to explore the ability of cutinase in the decolorization of molasses wastewater. Thermophilic cutinase from Thermobifida alba eliminated 76.1–78.2% of colorants and exhibited the highest decolorization efficiency amongst all of the cutinases tested. Cutinase from Thermobifida alba was immobilized on an affordable and efficient modified chitosan carrier and achieved a decolorization yield of 79.3–81.2%. This cutinase removed 66.3–71.1% of pigments and lasted continuously for 5 days. Importantly, it was also shown to continuously and effectively remove COD and BOD5. Compared to other enzymes, the immobilized cutinase from Thermobifida alba had the advantage of being low-cost and had a high expression level and activity. The results confirmed the decolorization occurred by destroying the conjugated system of melanoidins via an addition reaction by cutinase from Thermobifida alba. Thus, this study contributes a more practical and efficient approach to enzymatic decolorization of molasses wastewater.

Using pig manure to promote fermentation of sugarcane molasses alcohol wastewater and its effects on microbial community structure

Molasses alcohol wastewater (MAW) is difficult to be bio-treated and converted into biogas. In this study, MAW mixed with pig manure (PM) in different ratios was co-digested. Biogas production, chemical oxygen demand (COD) removal and the structure of microbial communities were monitored in the process. Our results showed that under the optimal COD ratio of PM:MAW (1.0:1.5), CODremoval and biogas yield were the highest. And in fermentation tanks with different PM to MAW ratios, the structure and composition of bacterial communities varied in the early and late stage. Furthermore, the type of main bacterial operational taxonomic units (OTUs) have no differences, yet the relative abundance of OTUs varied. The current research showed that there was a good potential to the use of PM as a co-digested material to anaerobic treatment of MAW and provided references for further improving bio-treatment of MAW.

Changes in microbial community structure in two anaerobic systems to treat bagasse spraying wastewater with and without addition of molasses alcohol wastewater

This study investigates the microbial community and structure in the internal circulation (IC) reactors that treat wastewater from bagasse spraying, with (reactor B) and without (reactor A) addition of molasses alcohol wastewater (MAW). The V3 regions in the 16S rRNA of bacteria were sequenced using illumina sequencing to characterize the microbial community structures. The results showed that there were approximately 34.8% more microorganisms were reduced, while the proportions of the three most predominant bacterial populations especially some sulfate-reducing bacteria increased in reactor B. The archaeal community composition was measured by PCR-DGGE (denaturing gradient gel electrophoresis) analysis and sequencing some clones from the 16S rRNA gene library. The results showed that numerous, mostly uncharacterized, archaeal genera are present in reactors A and B; the genus Methanomethylovorans was only detected in the samples that received MAW. This study demonstrated the significant effect of MAW on microbial communities in the wastewater treatment bioreactor.

Leaching Kinetics of Pyrolusite by Macromolecular Melanoidins of Molasses Alcohol Wastewater in H2SO4

The kinetics of reductive leaching of manganese from low grade pyrolusite using melanoidins of molasses alcohol wastewater as reducing agent in dilute sulfuric acid was investigated. The shrinking core model was applied to quantify the effects of reaction parameters on leaching rate of manganese. The leaching rate increases with the increase of the leaching temperature, sulfuric acid concentration and melanoidins concentration and the decreases of the particle size of pyrolusite. The leaching process follows the kinetics of a shrinking core model and the apparent activation energy is 56.2 kJ·mol-1. The experimental results indicate a reaction order of 0.54 for sulfuric acid concentration and 0.93 for melanoidins concentration. It is concluded that the reductive leaching of pyrolusite with macromolecular melanoidins of molasses alcohol wastewater is controlled by the diffusion through the ash/inert layer composed of the associated minerals.

Kinetics of Reductive Leaching of Low-grade Pyrolusite with Molasses Alcohol Wastewater in H 2SO 4

The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the effects of reaction parameters on leaching rate. The leaching rate increases with reaction temperature, concentrations of H 2SO 4 and organic matter in molasses alcohol wastewater increase and ore particle size decreases. The leaching process follows the kinetics of a shrinking core model and the apparent activation energy is 57.5 kJ·mol −1. The experimental results indicate a reaction order of 0.52 for H 2SO 4 concentration and 0.90 for chemical oxygen demand (COD) of molasses alcohol wastewater. It is concluded that the reductive leaching of pyrolusite with molasses alcohol wastewater is controlled by the diffusion through the ash/inert layer composed of the associated minerals.

Leaching of pyrolusite using molasses alcohol wastewater as a reductant

Extraction of manganese from a pyrolusite ore was investigated using molasses alcohol wastewater as a reducing agent in dilute sulfuric acid medium. The effects of molasses alcohol wastewater dosage, concentration of sulfuric acid, leaching temperature and reaction time were studied. High manganese recovery, coupled with relatively low Fe and Al extraction yields, was obtained with this leaching process. The optimal leaching conditions were obtained using 1.9 mol/L H 2SO 4 and 2.0 mL/g ratio of molasses alcohol wastewater to pyrolusite for 120 min at 90 °C. These conditions resulted in leaching yields of 93% for Mn, with relatively low recoveries of 37% for Fe and 25% for Al. These results demonstrate that molasses alcohol wastewater is a low cost resource, containing renewable and non-hazardous reducing agents (when compared to other available reagents) that can be used for manganese leaching under mild acidic conditions. In short, the method provides a good extraction yield while making an economically productive use of molasses alcohol wastewater.

Antioxidant and free radical scavenging activities of pigments extracted from molasses alcohol wastewater

The pigments from molasses alcohol wastewater were extracted by the macroporous resin adsorption method. The antioxidant and free radical scavenging activities of these pigments were also investigated. The adsorptive characteristics of five macroporous resins including HPD-600, HPD-500, D301-R, NKA-II and D296-R were studied and the results showed that the macroporous resin HPD-600 was most appropriate for extracting the pigments from molasses alcohol wastewater. The antioxidant and free radical scavenging activities of pigments extracted from alcohol wastewater were evaluated using nitrate, hydroxyl radical, superoxide anion radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) in vitro model systems. The pigment extract exhibited a concentration-dependent radical scavenging activity in all the systems. Meanwhile, scavenging activity of pigment extract in the DPPH system was found to be significantly ( P < 0.05) higher than that in other systems and the 50% inhibitory concentration (IC 50 value) was about 0.07 mg/ml. The scavenging effect of pigment extract on superoxide anion radical was very weak with IC 50 value greater than 10 mg/ml.