Effect of Two-Stage Treatment on the Biological Treatability of Strong Industrial Wastes

1993 ◽  
Vol 28 (2) ◽  
pp. 145-154 ◽  
Author(s):  
F. Germirli ◽  
D. Orhon ◽  
N. Artan ◽  
E. Ubay ◽  
E. Görgün
Keyword(s):  
Biological Treatment ◽  
Cheese Whey ◽  
Anaerobic Treatment ◽  
Industrial Wastes ◽  
Second Phase ◽  
Acid Plant ◽  
Two Stage ◽  
Effluent Standards ◽  
Biological Treatability ◽  
Very High

Some agro-industries generate wastewaters with very high COD concentrations and require two-stage biological treatment Inert or residual organic constituents of these wastewaters, even at very low ratios, play a major role in the compliance of effluent standards. In this study, two strong wastes, citric acid plant effluent and cheese whey were tested for their inert COD content. The experiments showed that the first-phase anaerobic treatment provided a major decrease in the residual COD, but introduced significant amounts of particulate residual COD to the second phase. A newly developed procedure was used for the assessment of the soluble and particulate residual COD.

The Effect of Residual COD on the Biological Treatability of Textile Wastewaters

1992 ◽  
Vol 26 (3-4) ◽  
pp. 815-825 ◽  
Author(s):  
D. Orhon ◽  
N. Artan ◽  
S. Büyükmurat ◽  
E. Görgün
Keyword(s):  
Biological Treatment ◽  
Treatment Process ◽  
Textile Effluents ◽  
Kinetic Information ◽  
A Value ◽  
Effluent Standards ◽  
Microbial Products ◽  
Biological Treatability ◽  
Activated Sludge Systems ◽  
Textile Wastewaters

Textile effluents often contain an array of chemicals with different biodegradation characteristics. Consequently, it is quite difficult to evaluate and interpret the degree of COD removal that can be attained by biological treatment without identifying COD portions that are resistant to biodegradation. This study evaluates the biological treatability of textile wastewaters generated by the knit and wowen fabric finishing category with specific emphasis on the assessment of different residual COD components. A new method is proposed to experimentally measure the initial particulate inert COD. The method is tested to yield a value of 73 mgl-1 for this COD component, corresponding to 16 % of the particulate COD in the textile sample. A previously developed procedure is used to quantify the initial soluble inert COD and the residual COD generated through microbial metabolism during the treatment process. The ratio of the inert fraction to the soluble COD of the textile effluents is found to vary between 0.076 and 0.22. A similar ratio in the range of 0.04 - 0.09 is calculated for the residual microbial products. The kinetic and stoichiometric constants associated with the biodegradable COD are also experimentally measured. The residual components, together with the kinetic information about biodegradable fractions, are used to simulate the performance of activated sludge systems by means of a relationship between the total effluent COD and the sludge age. The results indicate that the residual components practically dominate the effluent COD and seriously challenge related effluent standards.

Integrated treatment of olive oil mill effluents: effect of chemical and physical pretreatment on anaerobic treatability

1999 ◽  
Vol 40 (1) ◽  
pp. 345-355 ◽  
Author(s):  
M. Beccari ◽  
M. Majone ◽  
C. Riccardi ◽  
F. Savarese ◽  
L. Torrisi
Keyword(s):  
Phase Separation ◽  
Anaerobic Digestion ◽  
Olive Oil ◽  
Biological Treatment ◽  
Intermediate Phase ◽  
Continuous Process ◽  
Anaerobic Treatment ◽  
Integrated Treatment ◽  
Methane Yield ◽  
Very High

Difficulties met in the anaerobic treatment of olive oil mill effluents (OME) suggest the use of a chemico-physical pretreatment for the removal of biorecalcitrant and/or inhibiting substances (essentially lipids and polyphenols) as selectively as possible before anaerobic digestion. Laboratory scale experiments were carried out in order to identify pretreatment type and conditions capable of optimizing OME anaerobic digestion in terms both of kinetics and methane yield. Ultrafiltration, even if it allowed very high removals of lipids and polyphenols, was affected by poor selectivity (indeed, large amounts of biodegradable COD were also removed). Centrifugation turned out to be preferable to sedimentation owing to smaller volumes of separated phase. Results of great significance were obtained by adding Ca(OH)2 (up to pH 6.5) and 15 g/l of bentonite, and then feeding the mixture to the biological treatment without providing an intermediate phase separation. Indeed, the biodegradable matter adsorbed on the surface of bentonite was gradually released during the biotreatability test, thus allowing the same methane yield (referred to the total COD contained in untreated OME) both in scarsely diluted (1 : 1.5) pretreated OME and in very diluted (1 : 12) untreated OME. Application of a continuous process combining pretreatment (with Ca(OH)2 and bentonite) and anaerobic digestion without intermediate phase separation is suggested.

Two-stage chemical-biological treatment at Thessaloniki greater area WWTP - experiences and potentials

1995 ◽  
Vol 32 (9-10) ◽  
pp. 75-84 ◽  
Author(s):  
A. D. Andreadakis ◽  
G. H. Kristensen ◽  
A. Papadopoulos ◽  
C. Oikonomopoulos
Keyword(s):  
Biological Treatment ◽  
Treatment Plant ◽  
Cost Effective ◽  
Primary Treatment ◽  
Effective Control ◽  
Two Stage ◽  
Effluent Quality ◽  
Filamentous Microorganisms ◽  
Sludge Settling ◽  
The City

The wastewater from the city of Thessaloniki is discharged without treatment to the nearby inner part of the Thessaloniki Gulf. The existing, since 1989, treatment plant offers only primary treatment and did not operate since the expected effluent quality is not suitable for safe disposal to the available recipients. Upgrading of the plant for advanced biological treatment, including seasonal nitrogen removal, is due from 1995. In the mean time, after minor modifications completed in February 1992, the existing plant was put into operation as a two-stage chemical-biological treatment plant for 40 000 m3 d−1, which corresponds to about 35% of the total sewage flow. The operational results obtained during the two years operation period are presented and evaluated. All sewage and sludge treatment units of the plant perform better than expected, with the exception of the poor sludge settling characteristics, due to severe and persistent bulking caused by excessive growth of filamentous microorganisms, particularly M. Parvicella. Effective control of the bulking problem could lead to more cost-effective operation and increased influent flows.

The anaerobic treatment of a ligno-cellulosic substrate offering little natural pH buffering capacity

1998 ◽  
Vol 38 (4-5) ◽  
pp. 29-35 ◽  
Author(s):  
C. J. Banks ◽  
P. N. Humphreys
Keyword(s):  
Ph Control ◽  
Anaerobic Treatment ◽  
Buffering Capacity ◽  
Single Stage ◽  
Stable Operation ◽  
Reactor Performance ◽  
Two Stage ◽  
Ph Buffering ◽  
Stage System ◽  
The Stability

The stability and operational performance of single stage digestion with and without liquor recycle and two stage digestion were assessed using a mixture of paper and wood as the digestion substrate. Attempts to maintain stable digestion in both single stage reactors were unsuccessful due to the inherently low natural buffering capacity exhibited; this resulted in a rapid souring of the reactor due to unbuffered volatile fatty acid (VFA) accumulation. The use of lime to control pH was unsatisfactory due to interference with the carbonate/bicarbonate equilibrium resulting in wide oscillations in the control parameter. The two stage system overcame the pH stability problems allowing stable operation for a period of 200 days without any requirement for pH control; this was attributed to the rapid flushing of VFA from the first stage reactor into the second stage, where efficient conversion to methane was established. Reactor performance was judged to be satisfactory with the breakdown of 53% of influent volatile solids. It was concluded that the reactor configuration of the two stage system offers the potential for the treatment of cellulosic wastes with a sub-optimal carbon to nitrogen ratio for conventional digestion.

Biotransformation of nitrocellulose under methanogenic conditions

1996 ◽  
Vol 34 (5-6) ◽  
pp. 327-334 ◽  
Author(s):  
David L. Freedman ◽  
Bryan M. Caenepeel ◽  
Byung J. Kim
Keyword(s):  
Biological Treatment ◽  
Enrichment Culture ◽  
Basal Medium ◽  
Anaerobic Biodegradation ◽  
Anaerobic Treatment ◽  
Acid Digestion ◽  
Energetic Compounds ◽  
Nitrate Ester ◽  
Digestion Technique ◽  
Aerobic And Anaerobic

Treatment of wastewater containing nitrocellulose (NC) fines is a significant hazardous waste problem currently facing manufacturers of energetic compounds. Previous studies have ruled out the use of biological treatment, since NC has appeared to be resistant to aerobic and anaerobic biodegradation. The objective of this study was to examine NC biotransformation in a mixed methanogenic enrichment culture. A modified cold-acid digestion technique was used to measure the percentage of oxidized nitrogen (N) remaining on the NC. After 11 days of incubation in cultures amended with NC (10 g/L) and methanol (9.9 mM), the % N (w/w) on the NC decreased from 13.3% to 10.1%. The presence of NC also caused a 16% reduction in methane output. Assuming the nitrate ester on NC was reduced to N2, the decrease in CH4 represented almost exactly the amount of reducing equivalents needed for the observed decrease in oxidized N. An increase in the heat of combustion of the transformed NC correlated with the decrease in % N. There was no statistically significant decrease in % N when only NC was added to the culture, or in controls that contained only the sulfide-reduced basal medium. The biotransformed NC has a % N comparable to nonexplosive nitrated celluloses, suggesting that anaerobic treatment may be a technically feasible process for rendering NC nonhazardous.

scholarly journals Diagnosis and Monitoring of Volatile Fatty Acids Production from Raw Cheese Whey by Multiscale Time-Series Analysis

2021 ◽  
Vol 11 (13) ◽  
pp. 5803
Author(s):  
Antonio Lara-Musule ◽  
Ervin Alvarez-Sanchez ◽  
Gloria Trejo-Aguilar ◽  
Laura Acosta-Dominguez ◽  
Hector Puebla ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Time Series ◽  
Time Series Analysis ◽  
Multiscale Analysis ◽  
Volatile Fatty Acids ◽  
Cheese Whey ◽  
Anaerobic Treatment ◽  
Operating Conditions ◽  
Series Analysis ◽  
Key Variables

Anaerobic treatment is a viable alternative for the treatment of agro-industrial waste. Anaerobic digestion reduces organic load and produces volatile fatty acids (VFA), which are precursors of value-added products such as methane-rich biogas, biohydrogen, and biopolymers. Nowadays, there are no low-cost diagnosis and monitoring systems that analyze the dynamic behavior of key variables in real time, representing a significant limitation for its practical implementation. In this work, the feasibility of using the multiscale analysis to diagnose and monitor the key variables in VFA production by anaerobic treatment of raw cheese whey is presented. First, experiments were carried out to evaluate the performance of the proposed methodology under different operating conditions. Then, experimental pH time series were analyzed using rescaled range (R/S) techniques. Time-series analysis shows that the anaerobic VFA production exhibits a multiscale behavior, identifying three characteristic regions (i.e., three values of Hurst exponent). In addition, the dynamic Hurst exponents show satisfactory correlations with the chemical oxygen demand (COD) consumption and VFA production. The multiscale analysis of pH time series is easy to implement and inexpensive. Hence, it could be used as a diagnosis and indirect monitoring system of key variables in the anaerobic treatment of raw cheese whey.

Using cheese whey for hydrogen and methane generation in a two-stage continuous process with alternative pH controlling approaches

2009 ◽  
Vol 100 (15) ◽  
pp. 3713-3717 ◽  
Author(s):  
Nikolaos Venetsaneas ◽  
Georgia Antonopoulou ◽  
Katerina Stamatelatou ◽  
Michael Kornaros ◽  
Gerasimos Lyberatos
Keyword(s):  
Cheese Whey ◽  
Continuous Process ◽  
Two Stage ◽  
Methane Generation

BIOLOGICAL TREATABILITY OF AMINE LADEN REFINERY WASTEWATER

1994 ◽  
Vol 30 (3) ◽  
pp. 21-28 ◽  
Author(s):  
Nyuk-Min Chong
Keyword(s):  
Activated Sludge ◽  
Biological Treatment ◽  
Flow Reactor ◽  
Treatment Plant ◽  
Petroleum Products ◽  
System Stability ◽  
Refinery Wastewater ◽  
Continuous Flow Reactor ◽  
Biological Treatability

Mono- and Di- hydroxyl amines are used in the desulfuration processes for refined petroleum products. The refinery wastewater treatment plant may be shocked by amine laden wastewater periodically, bringing operation difficulties to the biological treatment units. Data on the treatability, shock load behaviour and on long term system stability of biological treatment of amines are therefore required. Shake-flask test results showed that pure diethanol amine and diisopropanol amines have characteristics of persistent compounds. Each of the two compounds has a prolonged lag time when first inoculated with indigenous activated sludge. Acclimated activated sludge in a continuous flow reactor treated a feed of ethanol amine with a 93 percent COD removal and a 98 percent nitrification, but the system was unstable because amine caused a bulking sludge. By physical retention of the activated sludge, 550 mg/l influent COD of amines was treated to m1 average 50 mg/l effluent COD. Sludge yield was approximately 0.26 mg MLSS per mg COD. The activated sludge system withstood a chm1ge of feed to a real refinery wastewater laden with the; amine. A mean cell residence time above five (5) days should be maintained for safe treatment of; amine.

scholarly journals CONSIDERATIONS ON RECYCLING POSSIBILITIES OF AGRO-INDUSTRIAL WASTES BY ANAEROBIC DIGESTION TREATMENT

1970 ◽  
Vol 63 ◽  
Author(s):  
Maria V. Morar
Keyword(s):  
Anaerobic Digestion ◽  
Biogas Production ◽  
Bacterial Flora ◽  
Waste Water Treatment ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Anaerobic Treatment ◽  
Industrial Wastes ◽  
Waste Water Treatment Plant ◽  
Industrial Processing

In our country, the developments of the measures for the prevention of the environmental pollution are aligning to the UE Directives. The costs for the treatment of the water wastes are continuously increasing, following to the also increasing of the investments costs. Therefore it is necessary to accord attention for the alternatives of cleaning, treating, respective recycling of the agro-industrial wastes and their reintroduction in the natural circuit. At the processing of the food results wastes with high organic charge. The effluents form the processing of dairy products, sugar, starch, beer yeasts as well as breweries or distilleries are getting fast into acids fermentation, finally resulting organic acids. Such process water wastes can be released in the canalization by dilution or by a suitable treating. As an example, for the distillery wastes (distillery slops) with a high dry matter contents (4-20%), the waste water treatment plant shall be designed properly (with mechanical separation step and biological treatment) to ensure the capacity of purifying according to the high flow and increased concentration, due to the high CBOD5 concentration. The treatment of such water wastes can be realized with aerobic processes, which suppose a high energetic consumption. While in the aerobic purifying processes 50 % of the CBOD5 is involved in the forming of biomass and slurry in excess, in the anaerobic treatment processes (anaerobic or methane digestion) a high part of the substrate (until 70 %) is metabolized through the metabolic transformation of bacterial flora, with production of biogas. Therefore, the concentrated water wastes, with potential for the energy production could offer a possibility of energy replacement in the own processing units. The paper presents a review of the anaerobic digestion for different wastes from the agro-industrial processing and their potential for the biogas production. There are presented possibilities of mixture, respectively of co-digestion of different wastes the agro-industrial processing with other wastes from the agriculture (from cereals processing, biomass, manure etc). Simultaneously biogas plants from the praxis with functioning characteristics are presented.

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