Two-Stage High Rate Digestion and Phosphorus Recovery

2007 ◽  
Vol 2 (1) ◽  
Author(s):  
Bernd Heinzmann ◽  
Gerd Engel
Keyword(s):  
Pilot Plant ◽  
Gas Production ◽  
Phosphorus Recovery ◽  
High Rate ◽  
Two Stage ◽  
Digestion Process ◽  
Volume Load ◽  
Sludge Disposal ◽  
Plant Trials ◽  
Degree Of Degradation

Improved sludge disposal can be achieved by intensified digestion. With the reduction of the hydraulic retention time and by higher dried solid matter of the sludge, the volume load increases. In the WWTP Waßmannsdorf the digestion could be intensified by higher DSM of the mixed sludge. Furthermore, by application of a two-stage high rate digestion process in first tests in 2002 a degree of degradation of around 50 % organic DSM was achieved. A high organic volume load of around 3.2 kg/m3 per day and a degradation rate of around 50 % were results of first pilot plant trials over a time period of more than 3 month with the two-stage high rate digestion process without usage of a rotating membrane disk filter and showed a stable and safe operation. By using the RMD in the next phase of the pilot plant trials more water will be extracted from the digested sludge and so the digestion time can be extended and the organic volume load can be increased, in order to achieve further improvements (degree of degradation and improved gas production). Furthermore, there is a high potential for P-recovery in the highly digested (mineralised) sludge. First trials show in principle that precipitated MAP could be separated by using the hydro-cyclone technique.

Highly Efficient Anaerobic Digestion with Thermal Pretreatment

1985 ◽  
Vol 17 (4-5) ◽  
pp. 529-539 ◽  
Author(s):  
M. Hiraoka ◽  
N. Takeda ◽  
S. Sakai ◽  
A. Yasuda
Keyword(s):  
Fatty Acids ◽  
Anaerobic Digestion ◽  
Pilot Plant ◽  
Molecular Size ◽  
Gas Production ◽  
Thermal Pretreatment ◽  
Anaerobic Digestion Process ◽  
Digestion Process ◽  
Before And After ◽  
Pilot Plant Study

The effectiveness of an anaerobic digestion process with thermal pretreatment at a comparatively low temperature was examined. The waste activated sludge was thermally pretreated in the process. A laboratory scale experiment and a pilot plant study were conducted. Changes in volatile acids concentration, in major constituents of sludge and in molecular size distribution were examined before and after thermal pretreatment and anaerobic digestion. Thermal pretreatment resulted in an increase of more than 30 percent in digestion gas production. The major substrates decomposed were fats in the pilot plant study. Glyceride fatty acids are decomposed with thermal pretreatment and produce volatile acids such as acetic and propionic acids. The volatile acids are directly utilized by anaerobes to produce methane. Organic matter such as fats and carbohydrates are depolymerized with thermal pretreatment and produce soluble intermediate compounds such as higher fatty acids. The intermediates are utilized in the anaerobic digestion process. These two major effects facilitate the methane production process.

High rate nitrifying trickling filters

1994 ◽  
Vol 29 (10-11) ◽  
pp. 47-52 ◽  
Author(s):  
B. Andersson ◽  
H. Aspegren ◽  
D. S. Parker ◽  
M. P. Lutz
Keyword(s):  
Nutrient Removal ◽  
Pilot Plant ◽  
Single Stage ◽  
High Rate ◽  
Control Methods ◽  
Predator Control ◽  
Trickling Filter ◽  
Two Stage ◽  
Trickling Filters ◽  
Pilot Plant Study

A two year pilot plant study has been performed in order to evaluate a nitrifying trickling filter (NTF) process within an upgrading project for increased nutrient removal. The operation of the filters was very stable without upsets due to predators. The filter microfauna was dominated by worms and the presence of filter fly larvae was limited. Suggested predator control methods like flooding or varying the flushing intensity did not affect the identified microfauna. By operating the filters in a two stage alternating series filtration mode, higher nitrification rates and lower effluent ammonia concentrations could be reached simultaneously in comparison to operating the filters in a single stage filtration mode.

scholarly journals Start-up of a decentralized pilot plant for the anaerobic treatment of domestic wastewater

2017 ◽  
Vol 12 (2) ◽  
pp. 386-395
Author(s):  
L. Fröba ◽  
M. Vega ◽  
F. Groß ◽  
A. Delgado
Keyword(s):  
Removal Efficiency ◽  
Pilot Plant ◽  
Municipal Wastewater ◽  
Domestic Wastewater ◽  
Synthetic Wastewater ◽  
Two Stage ◽  
Ammonium Removal ◽  
Digestion Process ◽  
Start Up ◽  
Service Water

This paper is about the set-up and start-up of a decentralized anaerobic pilot plant for producing domestic service water from domestic wastewater. The plant consists of a two-stage anaerobic digestion process for degrading organic matter and a third-stage for ammonium removal using the Anammox process. Each reactor was started independently with synthetic wastewater of stage-specific composition. They were then fed incrementally with municipal wastewater (MWW). The average removal efficiency of the two-stage digestion process operated with 100% MWW was 62% with 24-hour retention time. The Anammox stage achieved a maximum ammonium removal efficiency of 95% with 100% MWW, if the NO2-N to NH4-N ratio was set at 1.14. The plant was operated for 200 days. The average removal efficiencies were 81% for COD and 96% for NH4-N, with average treated effluent concentrations of 39 mg-COD/l and 1 mg-NH4-N/l. Thus the self-defined service water limits of 75 mg-COD/l and 10 mg-NH4-N/l were achieved easily.

Reduce odor and NH3 emission: condensation of the carbonatation vapors

2017 ◽  
pp. 534-537
Author(s):  
Nico Antens ◽  
Jan L.M. Struijs
Keyword(s):  
Direct Contact ◽  
Waste Heat ◽  
Pilot Scale ◽  
Sugar Production ◽  
Two Stage ◽  
Indirect Contact ◽  
Nh3 Emission ◽  
Emission Limits ◽  
Plant Trials ◽  
Contact Condensation

At beet sugar production, vapors from first and second carbonatation contain a significant amount of odor components, NH3 and waste heat, which are normally directly released into the environment. Due to sustainability motivations, obligations regarding odor nuisance and expected stricter regulations regarding NH3 emission limits, Suiker Unie decided to take measures to reduce emission via the carbonatation vapors. During the 2015 beet campaign, pilot scale plant trials have been performed to investigate the effectiveness of indirect contact and direct contact condensation of these vapors. Based on this experimental work a two-stage gas scrubbing concept was designed: in the first stage main goal is condensing the vapors and reuse the heat of condensation to heat up limed juice, while the actual scrubbing takes place in the second scrubber. This two-stage gas scrubbing installation has been built at the Vierverlaten factory and was started up in the 2016 beet campaign. The background, pilot scale trials, concept of design and achieved reductions in odor and NH3 emission at industrial scale are discussed.

Deep Shaft High Rate Aerobic Digestion: Laboratory and Pilot Plant Performance

1981 ◽  
Vol 16 (1) ◽  
pp. 71-90 ◽  
Author(s):  
F. Tran ◽  
D. Gannon
Keyword(s):  
Retention Time ◽  
Oxygen Transfer ◽  
Pilot Plant ◽  
High Rate ◽  
Plant Performance ◽  
High Solids ◽  
Aerobic Digestion ◽  
Volatile Solids ◽  
Solids Content ◽  
High Solids Content

Abstract The Deep Shaft process, originating from ICI Ltd. in the U.K., has been further developed by C-I-L Inc., Eco-Technology Division into an extremely energy efficient, high rate biological treatment process for industrial and municipal wastewaters. The Deep Shaft is essentially an air-lift reactor, sunk deep in the ground (100 - 160 m): the resulting high hydrostatic pressure together with very efficient mixing in the shaft provide extremely high oxygen transfer efficiencies (O.T.E.) of up to 90% vs 4 to 20% in other aerators. This high O.T.E. suggests real potential for Deep Shaft technology in the aerobic digestion of sludges and animal wastes: with conventional aerobic digesters an O.T.E. over 8% is extremely difficult to achieve. This paper describes laboratory and pilot plant Deep Shaft aerobic digester (DSAD) studies carried out at Eco-Research's Pointe Claire, Quebec laboratories, and at the Paris, Ontario pilot Deep Shaft digester. An economic pre-evaluation indicated that DSAD had the greatest potential for treating high solids content primary or secondary sludge (3-7% total solids) in the high mesophilic and thermophilic temperature range (25-60°C) i.e. in cases where conventional digesters would experience severe limitations of oxygen transfer. Laboratory and pilot plant studies have accordingly concentrated on high solids content sludge digestion as a function of temperature. Laboratory scale daily draw and fill DSAD runs with a 5% solids sludge at 33°C with a 3 day retention time have achieved 34% volatile solids reduction and a stabilized sludge exhibiting a specific oxygen uptake rate (S.O.U.R.) of less than 1 mgO2/gVSS/hour, measured at 20°C. This digestion rate is about four times faster than the best conventional digesters. Using Eco-Research's Paris, Ontario pilot scale DSAD (a 160 m deep 8 cm diameter u-tube), a 40% reduction in total volatile solids, (or 73% reduction of biodegradable VS) and a final SOUR of 1.2 mg02/gVSS/hour have been achieved for a 4.6% solids sludge in 4 days at 33°C, with loading rates of up to 7.9 kg VSS/m3-day. Laboratory runs at thermophilic temperatures (up to 60°C) have demonstrated that a stabilized sludge (24-41% VSS reduction) can be produced in retention time of 2 days or less, with a resulting loading rate exceeding 10 kg VSS/m3-day.

A Mathematical Model for the Anaerobic Digestion Process Applied to a Mixture of Night Soil and Septic Tank Sludge

1986 ◽  
Vol 18 (7-8) ◽  
pp. 239-248 ◽  
Author(s):  
Sung Ryong Ha ◽  
Dwang Ho Lee ◽  
Sang Eun Lee
Keyword(s):  
Mathematical Model ◽  
Anaerobic Digestion ◽  
Biomass Concentration ◽  
Gas Production ◽  
Septic Tank ◽  
Volatile Acid ◽  
Hydraulic Residence Time ◽  
Anaerobic Digestion Process ◽  
Digestion Process ◽  
Proposed Model

Laboratory scale experiments were conducted to develop a mathematical model for the anaerobic digestion of a mixture of night soil and septic tank sludge. The optimum mixing ratio by volume between night soil and septic tank sludge was found to be 7:3. Due to the high solids content in the influent waste, mixed-liquor volatile suspended solids (MLVSS) was not considered to be a proper parameter for biomass concentration, therefore, the active biomass concentration was estimated based on deoxyribonucleic acid (DNA) concentration in the reactor. The weight ratio between acidogenic bacteria and methanogenic bacteria in the mixed culture of a well-operated anaerobic digester was approximately 3:2. The proposed model indicates that the amount of volatile acid produced and the gas production rate can be expressed as a function of hydraulic residence time (HRT). The kinetic constants of the two phases of the anaerobic digestion process were determined, and a computer was used to simulate results using the proposed model for the various operating parameters, such as BOD5 and volatile acid concentrations in effluent, biomass concentrations and gas production rates. These were consistent with the experimental data.

scholarly journals Adjustment of Olive Fruit Temperature before Grinding for Olive Oil Extraction. Experimental Study and Pilot Plant Trials

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 586
Author(s):  
Eddy Plasquy ◽  
José María García Martos ◽  
María del Carmen Florido Fernández ◽  
Rafael Rubén Sola-Guirado ◽  
Juan Francisco García Martín
Keyword(s):  
Heat Treatment ◽  
Pilot Plant ◽  
Heating System ◽  
Oil Extraction ◽  
Warm Up ◽  
Precise Adjustment ◽  
Olive Cultivars ◽  
Plant Trials ◽  
Washing Water

Harvesting at high temperatures and bulk transport can negatively influence the quality of olives and lead to undesirable alterations in the extracted oil. Cooling the fruit in the field would be the most logical solution, but it means that the olives arrive too cold at the mill for immediate processing. In this work, the use of warm water in the washing tub to warm up the fruit before grinding instead of flash heat treatment on the paste was assessed in two experiments. In the first one, at the laboratory level, the temperature after milling was determined in three olive cultivars, previously stored at 5 or 10 °C, and then submerged at different water temperatures (25, 30, and 35 °C) for 15, 30, 45, and 60 s. In the second one, two batches of olives were cooled in the field at 5 °C and then conditioned with washing water to obtain a paste at the entrance of the pilot plant malaxer at 27 °C. The temperature of the olives was measured at five points from the discharging up to their entering, as paste, into the malaxer. The results demonstrated the feasibility of the method as the temperature of the ground olives was kept at the desired temperature (28 ± 1 °C). The trials highlight the potential for automating an even more precise adjustment of the temperature of the olives before milling once the washing tub is equipped with a safe heating system.

scholarly journals Continuous production of biohythane from hydrothermal liquefied cornstalk biomass via two-stage high-rate anaerobic reactors

2016 ◽  
Vol 9 (1) ◽  
Author(s):  
Bu-Chun Si ◽  
Jia-Ming Li ◽  
Zhang-Bing Zhu ◽  
Yuan-Hui Zhang ◽  
Jian-Wen Lu ◽  
...  
Keyword(s):  
Continuous Production ◽  
High Rate ◽  
Two Stage ◽  
Anaerobic Reactors

Effects of phosphorus recovery requirements on Swedish sludge management

2002 ◽  
Vol 46 (4-5) ◽  
pp. 435-440 ◽  
Author(s):  
E. Levlin ◽  
M. Löwén ◽  
K. Stark ◽  
B. Hultman
Keyword(s):  
Phosphorus Removal ◽  
Agricultural Land ◽  
Treatment Plant ◽  
Phosphorus Recovery ◽  
Molar Ratio ◽  
Toxic Substances ◽  
Biological Phosphorus Removal ◽  
Sludge Management ◽  
Small Stream ◽  
Sludge Disposal

Expected requirements of phosphorus recovery, restrictions on sludge disposal on landfill, and difficulties in obtaining consensus on sludge use on agricultural land has led to several development works in Sweden to change sludge management methods. Especially sludge fractionation has gained interest including following steps to recover products and separate transfer of toxic substances into a small stream. Commercial systems are offered based on technology by Cambi/KREPRO and BioCon and other companies and many other methods are under development. Iron salts are widely used in Sweden as precipitation agents for phosphorus removal and this technology has some disadvantages for phosphorus recovery compared with the use of biological phosphorus removal. The amount of chemicals needed for a KREPRO or a BioCon system was calculated for a treatment plant which has an addition of iron salt resulting in 1,900 mole Fe per tonne DS. The result was compared with the chemical consumption of recovery systems installed at plants with lower use of iron for precipitation. The chemical consumption in equivalents per tonne DS was found to be 5,000 + 6,000 * (molar ratio iron to phosphorus).

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