scholarly journals A study of activated sludge dewatering in experimental reed-planted or unplanted sludge drying beds

1995 ◽  
Vol 32 (3) ◽  
pp. 251-261 ◽  
Author(s):  
A. Liénard ◽  
Ph. Duchène ◽  
D. Gorini
Keyword(s):  
Dry Matter ◽  
Matter Content ◽  
Second Phase ◽  
Dry Matter Content ◽  
Oxidation Ditch ◽  
Mineralization Process ◽  
Sludge Dewatering ◽  
Second Growth ◽  
Sludge Drying ◽  
Solids Content

The study was performed over the period from June 1989 to December 1992 on 3 experimental concrete beds of 20 m2 each, constructed close to an extended aeration plant. Beds 1 and 2 were planted with reeds, bed 3 was considered as an unplanted control bed. During the first phase (June 89-May 90), most of the reeds in bed 2 died in spite of the influent sludge dose of 70 g of SS m−2 d−1. During the second phase (917 days) the 3 beds were naturally aerated from the bottom and fed with sludge that was directly extracted from the oxidation ditch (Dry Matter content 0.3%). The influent sludge load varied between 120 and 160 g of SS m−2 d−1 after the second growth season (with peak values of up to 215 g of SS m−2 d−1 in the summer of 1991). Even if bed 3 didn’t clog, the major contribution of the reeds to maintaining a high and regular liquid conductivity in the sludge has been proven, allowing easier and higher dosing of the planted beds. Monitoring of the percolation flow emphasised a high mineralization process in the rhizosphere. The accumulated sludge (Total Solids content ≈ 11%) can be dug out together with the reeds using a mechanical digger and spread on fields with a manure spreader. A regrowth of reeds occurs directly from rhizomes remaining in the drainage layer and in a few centimetres of sludge at the bottom of the bed.

Simulation of sludge dewatering on belt filters

2010 ◽  
Vol 61 (12) ◽  
pp. 3162-3168 ◽  
Author(s):  
Morten Lykkegaard Christensen ◽  
Rasmus Rosenlund Petersen ◽  
Lars Bjerg Jørgensen
Keyword(s):  
Dry Matter ◽  
Matter Content ◽  
Model Fit ◽  
Dry Matter Content ◽  
Sludge Dewatering ◽  
Optimum Load ◽  
Belt Speed ◽  
Drainage Time ◽  
Biological Sludge ◽  
Load Rate

A mathematical model for belt filters was developed to determine optimum load rate and belt speed during drainage of flocculated biological sludge. Numerical simulations were performed for belt filters with and without plows, and the model fit experimental data well. Experiments showed that highly compressible cakes were formed during drainage, which was important. Due to cake compression, the final sludge dry matter content increased with load rates as long as the drainage time was sufficiently long. The dry matter content could be increased by stacking the cake at the end of the process. An optimum load rate was found. At high load rates, the drainage time was too short and the dry matter content decreased with load due to high cake resistance. The resistance could be lowered by mixing cake and suspension during the process.

Key parameters in sludge dewatering: testing for the shear sensitivity and EPS content

2002 ◽  
Vol 46 (10) ◽  
pp. 105-114 ◽  
Author(s):  
L.H. Mikkelsen ◽  
T. Mascarenhas ◽  
P.H. Nielsen
Keyword(s):  
Laboratory Test ◽  
Dry Matter ◽  
Extracellular Polymeric Substances ◽  
Process Development ◽  
Matter Content ◽  
Dry Matter Content ◽  
Sludge Dewatering ◽  
Shear Sensitivity ◽  
Test Reactor

The fraction of extractable extracellular polymeric substances (EPS) and the shear sensitivity (kSS) are key parameters with respect to sludge dewatering, affecting the dry matter content of dewatered sludge and the dewatering rate and conditioner demand, respectively. Methods are described for determination of the two key parameters by use of the same laboratory test reactor. The implications of such characterisation with respect to dewatering are discussed based on examples of application to sludge processing and novel process development for sludge minimisation.

scholarly journals Sludge drying reed beds: full- and pilot-scale study for activated sludge treatment

2009 ◽  
Vol 60 (5) ◽  
pp. 1145-1154 ◽  
Author(s):  
S. Troesch ◽  
A. Liénard ◽  
P. Molle ◽  
G. Merlin ◽  
D. Esser
Keyword(s):  
Dry Matter ◽  
Loading Rate ◽  
Rest Period ◽  
Matter Content ◽  
Full Scale ◽  
Dry Matter Content ◽  
Loading Frequency ◽  
Reed Beds ◽  
Hydraulic Behaviour ◽  
Sludge Drying

Sludge drying reed beds have been used for dewatering and mineralization of sludge since the beginning of the 90s, but their insufficient performances in terms of Dry Matter [DM] content and mineralization of the sludge have made necessary new studies. Therefore, 8 pilots of 2 m2 each and a full-scale plant (13,000 p.e, 8 beds of 470 m2 in operation for 4 years) have been monitored to examine the influence of the sludge loading rate, the sludge quality and the loading frequency on the dewatering and mineralization efficiencies. Two filtration layers and two loading rhythms were tested on pilots which were fed at a loading rate of 25–30 kg DM m−2 yr−1 during the first year of operation (commissioning period). Hydraulic behaviour (infiltration rate, outflow), O2 and CO2 relative concentrations in the filtration media, redox potential, pollutants removal and dry matter content were assessed during all the study. The rheological quality of the extracted sludge from full scale beds was assessed and showed that its mechanical behaviour exceed those of sludge of comparable dry matter content, making its spreading easier. Therefore, this sludge could easily claim the status of solid and stabilized sludge according to the French regulation. Design and management recommendations (number of beds, loading rates, feeding/rest period) gained from the experiments results are suggested.

Integrating Vis-SWNIR spectrometer in a conveyor system for in-line measurement of dry matter content and soluble solids content of durian pulp

2021 ◽  
Vol 181 ◽  
pp. 111640
Author(s):  
Wanphut Saechua ◽  
Sneha Sharma ◽  
Natrapee Nakawajana ◽  
Kritsanaphon Leepaitoon ◽  
Rashphon Chunsri ◽  
...  
Keyword(s):  
Dry Matter ◽  
Matter Content ◽  
Soluble Solids ◽  
Dry Matter Content ◽  
Soluble Solids Content ◽  
Conveyor System ◽  
Line Measurement ◽  
Solids Content

scholarly journals Possibilities of using dairy compounds exposed to different treatments in dairy cow feeding

2011 ◽  
Vol 49 (No. 5) ◽  
pp. 205-210
Author(s):  
B. Z Saricicek
Keyword(s):  
Milk Yield ◽  
Tannic Acid ◽  
Feed Efficiency ◽  
Milk Fat ◽  
Dry Matter ◽  
Latin Square ◽  
Matter Content ◽  
Dry Matter Content ◽  
Positive Effects ◽  
Solids Content

This study was conducted to investigate the effects of untreated dairy compound feeds; DCF (control) and DCFs subjected to 2% fat (F); 2.5% tannic acid (TA); 2% fat + 2.5% tannic acid (F + TA) on the milk yield and composition. In the study, 4 cows of Jersey breed were used and 4 × 4 Latin square experimental design was applied. Normal milk yield, 4% fat corrected milk yield (FCM), dry matter content of milk, non-fat solids content of milk, CP content of milk, fat content of milk, lactose content of milk, crude ash content of milk, daily DM consumption of cows, feed efficiency according to normal milk yield of cows, feed efficiency according to the FCM of cows were 11.96, 12.14, 10.89 and 11.94 kg/day (P < 0.05); 14.16, 14.50, 13.06 and 13.70 kg/day (P < 0.05); 13.37, 13.34, 13.54 and 13.41% (P > 0.05); 8.12, 8.00, 8.35 and 8.19% (P > 0.05); 3.67, 3.70, 3.87 and 3.63% (P < 0.05); 5.25, 5.34, 5.19 and 5.22% (P > 0.05); 4.97, 4.812, 5.01 and 5.042% (P > 0.05); 0.75, 0.73, 0.74 and 0.73% (P > 0.05); 15.97, 15.84, 15.94 and 15.59 kg/day (P > 0.05); 1.34, 1.31, 1.46 and 1.31 kg feed DM/kg milk (P > 0.05); 1.13, 1.09, 1.22 and 1.14 kg feed DM/kg milk (P > 0.05), respectively. According to the results it can be stated that 2.5TA and 2F treatments had positive effects on FCM milk yield and milk protein yield.  

Sludge drying reed beds

2003 ◽  
Vol 48 (5) ◽  
pp. 101-109 ◽  
Author(s):  
S. Nielsen
Keyword(s):  
Activated Sludge ◽  
Dry Matter ◽  
Wastewater Treatment Plants ◽  
Regional Climate ◽  
Matter Content ◽  
Dry Matter Content ◽  
Digested Sludge ◽  
Anaerobically Digested Sludge ◽  
Sludge Drying ◽  
Full Operation

Sludge reduction occurs by dewatering (draining, evapotranspiration) and mineralization. Sludge from wastewater treatment plants (2,500-125,000 PE) is treated in sludge reed basin systems with 1-18 basins with loading rates of 25-2,200 tons dry matter/year for 10 years. In general, the sludge type is surplus activated sludge or a mix of mesophile digested sludge and surplus activated sludge. Dimensioning and design of reed basin systems for 10-year periods of operation depends on how the sludge is produced, rate of production (tons of dry matter/year), sludge type, quality and regional climate. Loading cycles are related to the sludge type and the age of the sludge reed systems. The period can be divided into a number of operating phases: commissioning, full operation, emptying and re-establishment of the system. Experience shows that efficiency makes special demands on the design of the systems and on the operational control in order to obtain a final dry matter content in the sludge residue of approximately 40% and the number of operating years. Sludge loadings with surplus activated sludge and surplus activated sludge mixed with anaerobically digested sludge amount to a maximum of 60 and 50 kg dry matter/m2.year, respectively.

CHANGES OF ACTINIDIA KOLOMIKTA FRUIT TEXTURE DURING STORAGE IN CONTROLLED ATMOSPHERE CHAMBERS

2015 ◽  
Author(s):  
Aurelija PAULAUSKIENĖ ◽  
Viktoras PRANCKIETIS ◽  
Toma BARČYTĖ ◽  
Živilė TARASEVIČIENĖ
Keyword(s):  
Yield Point ◽  
Dry Matter ◽  
Matter Content ◽  
Soluble Solids ◽  
Dry Matter Content ◽  
Controlled Atmosphere ◽  
Soluble Solids Content ◽  
Flesh Firmness ◽  
Texture Parameters ◽  
Solids Content

Investigations were carried out in 2013. A. kolomikta cv. ‘Laiba’, ‘Lankė’, ‘Landė’, ‘Paukštės Šakarva’ fruits were picked at the technical maturity stage. The amount of dry matter, soluble solids and texture parameters were established in fruits after harvesting and during storage. Fruits stored for 8 weeks in controlled atmosphere chambers with different air parameters (No. 1–21 % O2, No. 2–0.5 % O2, No. 3–1 % O2, No. 4–1 % O2 and 1 % CO2). Dry matter, soluble solids and texture analysis were done biweekly. The amount of dry matter was determined by drying the samples to the constant mass at the temperature of 105 ºC. Soluble solids content was determined by the refractometric method. Fruit texture parameters were analysed by Texture analyser. The results of chemical analysis at harvest time showed that the biggest amount of dry matter and the highest value of flesh firmness were in ‘Laiba’ fruits, soluble solids in ‘Landė’ fruits. The highest value of bio-yield point was established in ‘Paukštės Šakarva’ fruits. Results of analysis showed that dry matter content as well as soluble solids content of A. kolomikta fruits increases during storage in controlled atmosphere chambers. The highest increase in soluble solids content was in chamber No. 4 and the highest increase in dry matter content was in chamber No. 2 compared with fruits at harvest time. A. kolomikta fruits texture changes during fruit ripening with bio-yield point and flesh firmness declining. The largest decrease of bio-yield point and flesh firmness of fruits occurred in two weeks of storage.

Optimum harvest date of maize for biogas and silage purposes

2009 ◽  
Vol 57 (2) ◽  
pp. 119-125
Author(s):  
G. Hadi
Keyword(s):  
Dry Matter ◽  
Biogas Production ◽  
Weather Conditions ◽  
Vegetation Period ◽  
Dry Mass ◽  
Matter Content ◽  
Harvest Date ◽  
Dry Matter Content ◽  
Dry Matter Yield ◽  
Vegetative Organs

The dry matter and moisture contents of the aboveground vegetative organs and kernels of four maize hybrids were studied in Martonvásár at five harvest dates, with four replications per hybrid. The dry matter yield per hectare of the kernels and other plant organs were investigated in order to obtain data on the optimum date of harvest for the purposes of biogas and silage production.It was found that the dry mass of the aboveground vegetative organs, both individually and in total, did not increase after silking. During the last third of the ripening period, however, a significant reduction in the dry matter content was sometimes observed as a function of the length of the vegetation period. The data suggest that, with the exception of extreme weather conditions or an extremely long vegetation period, the maximum dry matter yield could be expected to range from 22–42%, depending on the vegetation period of the variety. The harvest date should be chosen to give a kernel moisture content of above 35% for biogas production and below 35% for silage production. In this phenophase most varieties mature when the stalks are still green, so it is unlikely that transport costs can be reduced by waiting for the vegetative mass to dry.

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