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Odorous Compounds (odorous + compound)
Selected AbstractsOdorous compounds in paperboard as influenced by recycled material and storagePACKAGING TECHNOLOGY AND SCIENCE, Issue 4 2001Gottfried Ziegleder Abstract Many volatile compounds can be identified in unprinted paperboard by means of steam distillation in combination with capillary gas chromatography, mass spectrometry and olfactometry. Paperboards produced with recycled material exhibit additional volatiles which partly contribute to off-odours. Using sniffing techniques, benzaldehyde, acetophenone, 1-octen-3-ol, 1-octen-3-one, 2-nonenal, methylguajacol, butanoic and 3-methyl butanoic acid were identified as the most odorous volatiles. The aromatic substances mainly exude from inks and printing solvents in waste materials used for paperboard manufacturing. During storage under controlled conditions, the microbial load of paperboard decreased slightly, and no odorous metabolic products were generated. Copyright © 2001 John Wiley & Sons, Ltd. [source] Treatment of paper and pulp wastewater and removal of odorous compounds by a Fenton-like process at the pilot scaleJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2006José L Tambosi Abstract A Fenton-like process, involving oxidation and coagulation, was evaluated for the removal of odorous compounds and treatment of a pulp and paper wastewater. The main parameters that govern the complex reactive system [pH and Fe(III) and hydrogen peroxide concentrations] were studied. Concentrations of Fe(III) between 100 and 1000 mg L,1 and of H2O2 between 0 and 2000 mg L,1 were chosen. The main mechanism for color removal was coagulation. The maximum COD, color and aromatic compound removals were 75, 98 and 95%, respectively, under optimal operating conditions ([Fe(III)] = 400 mg L,1; [H2O2] = 500,1000 mg L,1; pH = 2.5; followed by coagulation at pH 5.0). The biodegradability of the wastewater treated increased from 0.4 to 0.7 under optimal conditions and no residual hydrogen peroxide was found after treatment. However, partially or non-oxidized compounds present in the treated wastewater presented higher acute toxicity to Artemia salina than the untreated wastewater. Based on the optimum conditions, pilot-scale experiments were conducted and revealed a high efficiency in relation to the mineralization of organic compounds. Terpenes [(1S)-,-pinene, ,-pinene, (1R)-,-pinene and limonene] were identified in the wastewater and were completely eliminated by the Fenton-like treatment. Copyright © 2006 Society of Chemical Industry [source] Biofiltration of nuisance sulfur gaseous odors from a meat rendering plantJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 12 2002Zarook Shareefdeen Abstract This paper presents a case study of a commercial biofilter, treating air streams contaminated with several odorous compounds including dimethyl sulfide, ammonia, methanethiol, hydrogen sulfide and ethylamine. The biofilter is packed with a proprietary wood-based (BIOMIXÔ) medium which is designed to provide a good biological environment, pH buffer capacity, low pressure drop and resistance to compaction. This commercial biofilter treats a contaminated air volume of 15,000 actual cubic feet per minute (acfm) from a meat rendering and wastewater treatment operation with a 30-s empty bed residence time. The case study includes a novel gas sampling procedure and characterization of biofilter air streams through a mobile Fourier transform infrared system and olfactometer analysis. The results confirmed the good distribution of air, moisture and bacterial population across the medium. Four years of consistent performance of this commercial biofilter with >99% removal of 24,500 odor units demonstrates that biofilters can be successfully applied for the removal of highly odorous gaseous sulfur compounds. © 2002 Society of Chemical Industry [source] EVALUATION OF OLFACTORY INTENSITY: COMPARATIVE STUDY OF TWO METHODSJOURNAL OF SENSORY STUDIES, Issue 4 2004BORIANA ATANASOVA ABSTRACT Two experimental procedures recommended for the evaluation of the psychophysical characteristics of odorous compounds, olfactory matching with the 1-butanol scale and cross-modality matching with the finger span are compared. The intensity of ethyl butyrate and guaiacol solutions presented at four different concentration levels was evaluated by a panel of sixteen subjects over five repetitions using the two methods. Each stimulus was delivered to the subject from a Teflon bag through a nose-shaped glass sniffing port. The discrimination ability, repeatability, panel homogeneity and within-subject variability of the methods were assessed. Results indicate that with both methods, subjects were able to highly discriminate the presented concentration levels of the odorants. There were no great difference in repeatability and the same individual variability was observed between both methods. However, the smaller within-subject variability highlighted for the 1-butanol scale method suggested that this method is potentially more powerful than finger-span method. [source] | ||||||||||