The degradation of highly concentrated organic wastewater by the sand layer method

1997 ◽  
Vol 35 (8) ◽  
pp. 223-229
Author(s):  
Masatomo Nakayama ◽  
Keijiro Enari
Keyword(s):  
Waste Water ◽  
Organic Waste ◽  
Lower Layer ◽  
Removal Rate ◽  
Column Experiment ◽  
Sand Layer ◽  
Biological Degradation ◽  
Sand Column ◽  
Methanogenic Activity ◽  
Seed Sludge

The osmotic action of highly concentrated organic waste water through soil was investigated by a column experiment. In this experiment, 50cm high sand-filled columns were used. The experiment included to estimate the toxic effects of mercury on the biological degradation of highly concentrated organic waste water. By adding seed sludge to the top of the sand column, 90% of the TOC was removed. The TOC was removed within the first 20-30cm of the sand layer. Though the removal rate of T-N was low, the T-P removal rate was over 86%. The effect of mercury on the removal of TOC, T-N, and T-P was not marked in either case. Both the acidogenic activity and the methanogenic activity were measured, and they showed higher values in the upper layer compared with the lower layer. The values of these activities were low in the column experiment with mercury.

Application of the UASB-Reactor for Anaerobic Treatment of Paper and Board Mill Effluent

1985 ◽  
Vol 17 (1) ◽  
pp. 61-75 ◽  
Author(s):  
L H A Habets ◽  
J H Knelissen
Keyword(s):  
Waste Water ◽  
Water Treatment ◽  
Energy Savings ◽  
Hydraulic Retention Time ◽  
Waste Water Treatment ◽  
Anaerobic Treatment ◽  
Raw Material ◽  
Uasb Reactor ◽  
Seed Sludge ◽  
Uasb Reactors

Within the holding of Bührmann-Tetterode NV, 7 Dutch paper and board mills are operating, all of them using mainly waste paper as raw material. While three of them completely closed their watercircuits, two other mills put into practice biological waste water treatment namely anaerobic and anaerobic/aerobic. Number 6 is realising an anaerobic plant this year and for number 7 research is still being carried out, dealing with several unfavourable aspects. In September 1981 research for anaerobic treatment (UASB reactors) was started. After good results had been achieved on laboratory scale (301), further investigations were started on semitechnical scale (50 m3). In both cases the anaerobic seed sludge granulated after a while and loadings up to 20 kg COD/m3.d could be handled. COD-removal was 70 per cent, even when the hydraulic retention time was only 2.5 hours. In April 1983 a 70 m3 practical scale UASB reactor was started up at the solid board mill of Ceres. In October 1983 a full scale plant was started up at Papierfabriek Roermond. This plant consists of a 1,000 m3 UASB reactor and a 70 m3 gasholder. It has been designed and constructed by Paques BV and is used for pretreatment of effluent, in order to reduce the loading of the activated sludge plant. Besides energy savings on the oxygen input, about 1 million m3/year of biogas is being generated and is used for steamproduction. Both plants are working satisfactorily. Investment costs appeared to be relatively low. At Ceres, pay-out time is 1.5 year, while at Papierfabriek Roermond waste water treatment is cheaper than before, although capacity is doubled.

Analysis of environmental factors affecting methane production from high-solids organic waste

1997 ◽  
Vol 36 (6-7) ◽  
pp. 493-500 ◽  
Author(s):  
J. J. Lay ◽  
Y. Y. Li ◽  
T. Noike ◽  
J. Endo ◽  
S. Ishimoto
Keyword(s):  
Moisture Content ◽  
Methane Production ◽  
Organic Waste ◽  
High Solids ◽  
Methanogenic Activity ◽  
Factors Affecting ◽  
Bacterial System ◽  
Sludge Cake ◽  
Production Curve ◽  
Ph Range

A simple model developed from the Gompertz equation was used to describe the cumulative methane production curve in the batch culture. By using this model, three key parameters, namely methane production rate, potential and lagphase time, in a cumulative methane production curve were exactly estimated based on the experimental data. The results indicate that each gram of dry organic waste of a sludge cake, meat, carrot, rice, potato and cabbage had a methane production potential of 450, 424, 269, 214, 203 and 96 mL, respectively. The methanogenic activity of these digesters decreased with a decrease in the moisture content. The moisture content threshold limit, at which the methanogenic activity dropped to zero, was found to be 56.6% for the sludge cake, but greater than 80% for meat, carrot and cabbage. In the high-solids sludge digestion, the relative methanogenic activity dropped from 100% to 53% when the moisture content decreased from 96% to 90%. The rate of methane production at moisture contents of 90% to 96% functioned in a pH range between 6.6 and 7.8, but optimally at pH 6.8, and the process may fail if the pH was lower than 6.1 or higher than 8.3. On the other hand, the methanogenic activity was dependent on the level of ammonium, NH4+, but not free ammonia, NH3, indicating that the NH4+ was the more significant factor rather than the NH3 in affecting the methanogenic activity of a well-acclimatized bacterial system. In the wide pH range of 6.5 to 8.5, the methanogenic activity decreased with the increase in the NH4+; dropped 10% at the NH4+-N concentration of 1670-3720 mg·L−1, 50% at 4090-5550 mg·L−1 and dropped to zero at 5880-6600 mg·L−1. However, the lagphase time was dependent on the NH3 level, but not on NH4+, and when NH3-N was higher than 500 mg·L−1, a notable shock was observed. This suggests that the NH3 level was the more sensitive factor than the NH4+ level for an unacclimatized bacterial system.

scholarly journals Methods to Improve nZVI Adsorbance on Silicates Surface for Nitrate Reduction

2021 ◽  
Author(s):  
◽  
Handayani Fraser
Keyword(s):  
Silica Fume ◽  
Western Australia ◽  
Column Experiment ◽  
Exchangeable Cation ◽  
Sand Column ◽  
Silica Surfaces ◽  
Pure Silica ◽  
Acid Washing ◽  
Silicate Surface ◽  
Aluminium Silicate

<p>Efforts to remove excess nitrate in the groundwater typically involves expensive ion-exchange membranes or slow reacting bio-reactors. Nano-sized zero valent iron (nZVI) has been used successfully to reduce nitrate into ammonia in various sites in USA and Europe. However, nZVI has a number of major setbacks associated with it, namely the tendency to agglomerate due to magnetic properties, and the possible toxicity due to the nano-sized material.  To circumvent these two setbacks, nZVI could be adsorbed onto solid support. In this research, geothermal sediment microsilicate 600 (Misi) was utilised as a support. Initial results suggested that Misi has potential as a support for nZVI, however modifications were required to improve the adsorbance of nZVI onto Misi surface. Calcination, activation, acid wash and iron oxyhydroxide coating were used as surface modifications for Misi. It was found that the two most important modifications for nZVI adsorption was calcination at either 400 or 600 °C and acid washing in 5.6 M HCl.  Equipped with this knowledge, other silica and silicates were also used to adsorb nZVI. For pure silica surfaces, 3-APTES and 3-TPTMS ligands and pore enlarging methods of calcination of porogen and salt wash were also used. nZVI was not able to be fully adsorbed on pure silica surfaces. Four other silicates were examined: Rice husk ash, Western Australia silica fume, Mt Piper fly ash, and precipitated aluminium silicate. Of these, only Western Australia silica fume and precipitated aluminium silicate showed potential as nZVI support. Based on the SEM-EDS XRD data of all the silica and silicates, it could be tentatively concluded that nZVI requires an aluminium silicate surface for successful adsorption. Aluminium silicate surfaces typically has an exchangeable cation present, and this cation might play a part in nZVI adsorption.  The nZVI/Misi surface was then utilised to reduce nitrate. It was discovered that even though activation and FeOOH did not play a part in nZVI adsorption onto Misi surface, these two steps were important in reduction of nitrate, as the presence of activation and FeOOH increase the reduction of nitrate significantly within 60 minutes. The Misi-supported nZVI were also shown to be more stable in dispersion, and less agglomerated as shown in a sand column experiment.</p>

Experimental Research of Decoloring Treatment on Vitamin B12 Wastewater

2013 ◽  
Vol 295-298 ◽  
pp. 1209-1214 ◽  
Author(s):  
Si Hang Shan ◽  
Peng Fei Fan ◽  
Yi Xing ◽  
Geng Qiao
Keyword(s):  
Waste Water ◽  
Vitamin B12 ◽  
Experimental Research ◽  
Removal Rate ◽  
Color Removal ◽  
The Other ◽  
Vitamin B ◽  
Reaction Conditions ◽  
Pharmaceutical Factory

Two kinds of vitamin B12 waste water from a pharmaceutical factory were treated separately by methods of combining micro-electrolysis with physiochemical and O3 oxidation. Effects of the reaction conditions on the removal rate of color were investigated. Results showed that the color removal rate of vitamin B12 waste water, which was treated by combined micro-electrolysis and physiochemical treatment reached 71.25%, while the color removal rate of the other waste water which treated by O3 oxidation reached 68.80%. The decolorizing treatment of those different natures of vitamin B12 waste water effectively provides a useful reference for this kind of waste water.

An experimental study of vertical infiltration into a structurally unstable swelling soil, with particular reference to the infiltration throttle

Soil Research ◽  
1973 ◽  
Vol 11 (2) ◽  
pp. 121 ◽  
Author(s):  
BJ Bridge ◽  
N Collis-George
Keyword(s):  
Soil Column ◽  
Soil Surface ◽  
Fine Sand ◽  
Coarse Sand ◽  
Sand Layer ◽  
Wetting Front ◽  
Sand Column ◽  
Swelling Soil ◽  
Potential Gradients ◽  
Moisture Potential

The infiltration phenomena associated with a structurally unstable swelling soil are compared with those of a two-layer stable system of a fine sand layer over coarse sand, the fine sand simulating a slaked layer at the soil surface. Water content and bulk density are measured using dual source gamma ray attenuation, pore water pressures by means of individual tensiometer-transducer systems, and soil temperatures by means of individual thermistor-bridge systems. Analysis of the sand column using well-established principles shows that after the wetting front has passed the texture boundary, infiltration is controlled by Kmax of the fine sand layer and the negative moisture potential in the coarse sand at the texture boundary. After the wetting front penetrates the column, the moisture potential at the texture boundary becomes steady and is unaffected by the development of a capillary fringe and outflow at the base of the column. The negative moisture potentials at the texture boundary give rise to potential gradients up to 6.0 in the simulated slaked layer, and an infiltration rate several times that of Kmax. The low flow rates caused by the fine sand layer give rise to an unstable wetting front in the coarse sand and severe 'fingering' occurs. In the swelling soil column, with aggregates of the same size as the coarse sand, the infiltration throttle occurs immediately below the visibly slaked layer and not at the ground surface. Potential gradients through the throttle reach a maximum of 5.9 similar to that in the layered sand column, but the infiltration behaviour of swelling soil differs from the latter in other respects. Infiltration into the former does not occur under isothermal conditions, a 'hot front' 3�C above ambient occurring 2-3 mm ahead of the wetting front, and infiltration does not reach a constant rate because of changes in the hydraulic properties of the throttle with time. Moisture profiles in the swelling soil column during infiltration show the various zones described by Bodman and Colman (1944) for non-swelling soils. An enlarged apparent transition zone extend to 12 cm below the soil surface. Other properties such as density, moisture content, and total potential suggest that much of this apparent transition zone is really part of a transmission zone made up of layers of soil which have different properties because of swelling.

Microplastics and earthworms in soils: A case study on translocation, toxicity and fate

2020 ◽  
Author(s):  
Nils Dietrich ◽  
Daniel Wilkinson ◽  
Florian Hirsch ◽  
Magdalena Sut-Lohmann ◽  
Antonia Geschke ◽  
...  
Keyword(s):  
Organic Waste ◽  
Soil Column ◽  
Column Experiment ◽  
Lumbricus Terrestris ◽  
Natural Soil ◽  
Arable Soils ◽  
Different Types ◽  
Soil Column Experiment ◽  
Illegal Waste

&lt;p&gt;Microplastics are not only found in marine and lacustrine environments but also in soils. Microplastics enter natural soil environments from legal or illegal waste deposition. In arable soils, microplastics often stem from the decomposition of plastic sheeting. The accumulation of (micro-)plastic from garbage bags in which biological waste is often disposed, is also a significant problem for the recycling and composting of organic waste. Commercially available compostable bags are advertised as degradable. Thus, these compostable bags ought to accumulate less in soils than non-compostable bags. We present a pilot study to determine the preference of earthworms (Lumbricus terrestris and Eisenia hortensis) for taking up and translocating different types of microplastic in soils. Our initial findings from the soil column experiment suggest that the earthworms show a strong tendency for the uptake of microplastic.&amp;#160; We also observed direct and indirect transport of microplastic by earthworms from the surface to deeper parts of the soil columns.&lt;/p&gt;

Rapid start-up of a nitrifying reactor using aerobic granular sludge as seed sludge

2012 ◽  
Vol 65 (3) ◽  
pp. 581-588 ◽  
Author(s):  
Naohiro Kishida ◽  
Goro Saeki ◽  
Satoshi Tsuneda ◽  
Ryuichi Sudo
Keyword(s):  
Removal Rate ◽  
Granular Sludge ◽  
Ammonia Removal ◽  
High Rate ◽  
Aerobic Granular Sludge ◽  
Nitrite Accumulation ◽  
Ammonia Oxidizing Bacteria ◽  
Continuous Stirred Tank Reactor ◽  
Start Up ◽  
Seed Sludge

In this study, the effectiveness of aerobic granular sludge as seed sludge for rapid start-up of nitrifying processes was investigated using a laboratory-scale continuous stirred-tank reactor (CSTR) fed with completely inorganic wastewater which contained a high concentration of ammonia. Even when a large amount of granular biomass was inoculated in the reactor, and the characteristics of influent wastewater were abruptly changed, excess biomass washout was not observed, and biomass concentration was kept high at the start-up period due to high settling ability of the aerobic granular sludge. As a result, an ammonia removal rate immediately increased and reached more than 1.0 kg N/m3/d within 20 days and up to 1.8 kg N/m3/d on day 39. Subsequently, high rate nitritation was stably attained during 100 days. However, nitrite accumulation had been observed for 140 days before attaining complete nitrification to nitrate. Fluorescence in situ hybridization analysis revealed the increase in amount of ammonia-oxidizing bacteria which existed in the outer edge of the granular sludge during the start-up period. This microbial ecological change would make it possible to attain high rate ammonia removal.

Anaerobic biodegradation of 2,4,6-trichlorophenol by methanogenic granular sludge: role of co-substrates and methanogenic inhibition

2009 ◽  
Vol 59 (7) ◽  
pp. 1449-1456 ◽  
Author(s):  
D. Puyol ◽  
A. F. Mohedano ◽  
J. L. Sanz ◽  
J. J. Rodríguez
Keyword(s):  
Volatile Fatty Acids ◽  
Removal Rate ◽  
Granular Sludge ◽  
Anaerobic Biodegradation ◽  
Methanogenic Activity ◽  
The Third ◽  
Specific Methanogenic Activity ◽  
Methanol Yeast ◽  
Complete Dechlorination

The influence of several co-substrates in the anaerobic biodegradation of 2,4,6-trichlorophenol (246TCP) by methanogenic granular sludge as well as in methanogenesis inhibition by 246TCP has been studied. 4 g-COD·L−1 of lactate, sucrose, volatile fatty acids (VFA) acetate:propionate:butyrate 1:1:1, ethanol, methanol, yeast extract (YE), and 2 g-COD·L−1 of formate and methylamine were tested. Two concentrations of 246TCP: 80 mg·L−1 and 113 mg·L−1 (this last corresponding to the EC50 for acetotrophic methanogenesis) were tested. Three consecutive co-substrate and nutrient feedings were accomplished. 246TCP was added in the second feed, and the 246TCP removal rate increased considerably after the third feed. Accumulated metabolites after ortho-dechlorination, either 4-chlorophenol (4CP) (when methanol, ethanol or VFA were used as co-substrates) or 2,4-dichlorophenol (24DCP) (with lactate) avoided the complete dechlorination of 246TCP. With methylamine and formate this compound was degraded only partially. Monochlorophenols biodegradation was partially achieved with YE, but both 24DCP and 2,6-dichlorophenol (26DCP) were accumulated. In the presence of sucrose para-dechlorination was observed. 246TCP was better tolerated by methanogens when ethanol and methanol were added because of the highest specific methanogenic activity achieved with these co-substrates. Methanol and ethanol were the best co-substrates in the anaerobic biodegradation of 246TCP.

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