A Comparison of the Efficiency of Five Agitator Designs for Solids Suspension Duties at High Solids Concentrations

1992 ◽  
pp. 117-130 ◽  
Author(s):  
N. I. Heywood ◽  
S. Rehman ◽  
R. G. Whittemore
Keyword(s):  
High Solids ◽  
Solids Suspension

Corrosion monitoring and root cause identification in high solids concentrators

TAPPI Journal ◽  
2016 ◽  
Vol 15 (7) ◽  
pp. 467-477
Author(s):  
PASI NIEMELAINEN ◽  
MARTTI PULLIAINEN ◽  
JARMO KAHALA ◽  
SAMPO LUUKKAINEN
Keyword(s):  
Paper Industry ◽  
Black Liquor ◽  
Construction Materials ◽  
Open Circuit ◽  
Process Conditions ◽  
Potential Range ◽  
Corrosion Monitoring ◽  
General Corrosion ◽  
High Solids ◽  
Passive Area

Black liquor high solids (about 80%) concentrators have often been found to suffer from aggressive corrosion. In particular, the first and second effect bodies are susceptible to corrosion attacks resulting in tube leaks and wall thinning, which limit the availability and lifetime of evaporator lines. Corrosion dynamics and construction materials have been studied extensively within the pulp and paper industry to understand the corrosion process. However, it has been challenging to identify root causes for corrosion, which has limited proactive measures to minimize corrosion damage. Corrosion of the first phase concentrator was studied by defining the potential regions for passive area, stress corrosion cracking, pitting corrosion, and general corrosion. This was achieved by using a technique called polarization scan that reveals ranges for the passive area in which the equipment is naturally protected against corrosion. The open circuit potential, also known as corrosion potential, and linear polarization resistance of the metal were monitored online, which allowed for definition of corrosion risks for stainless steel 304L and duplex stainless steels 2205 and SAF 2906. An online temperature measurement added insight to the analysis. A process diagnostics tool was used to identify root causes of the corrosion attacks. Many of the root causes were related to process conditions triggering corrosion. Once the metal surface was activated, it was difficult to repassivate the metal naturally unless a sufficient potential range was reached.

High solids concentration of black liquor.

1985 ◽  
Vol 39 (1) ◽  
pp. 65-69 ◽  
Author(s):  
Tatsuo Nakano ◽  
Shuichi Nagato ◽  
Michihiro Nakura
Keyword(s):  
Black Liquor ◽  
High Solids ◽  
Solids Concentration

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.

High solids nanobinders

2007 ◽  
Vol 2007 (6) ◽  
pp. 4-5
Keyword(s):  
High Solids

scholarly journals Viability of Lactobacillus casei ATCC 393 and properties in Andean blackberry suspensions with probiotic and prebiotic characteristics

DYNA ◽  
2019 ◽  
Vol 86 (210) ◽  
pp. 179-186
Author(s):  
Zaira Tatiana Marin Arango ◽  
Misael Cortés Rodriguez ◽  
Olga Ines Montoya Campuzano ◽  
Julio Cesar Arango Tobón
Keyword(s):  
Zeta Potential ◽  
Mass Fraction ◽  
Lactobacillus Casei ◽  
Food Industry ◽  
Functional Foods ◽  
Total Solid ◽  
Dependent Variables ◽  
Solids Suspension ◽  
Probiotic Microorganism ◽  
Spray Dried

Food industry has grown in recent years mainly due to the supply of functional foods with probiotics and prebiotics. The viability of Lactobacillus casei and the properties of blackberry suspensions added with inulin were evaluated using a central design composed of the following factors: mass fraction of total solid blackberry concentrate (XTSBC) (0.103-0.120), [McFarland] (6-10), inulin (2.78-3.68%), and mass blackberry concentrate (BC)/mass inoculum (R) (5-20); and the dependent variables: moisture (M), pH, acidity, °Brix, total solids suspension (TSS), viscosity (μ), zeta potential (z), and Log CFU/g. Results of the experimental optimization of multiple responses were: XTSBC (0.103), [McFarland] (10), inulin (3.12%w/w), and R (18.5); being the dependent variables: M=86.7±0.0%, pH=2.74±0.01, acidity=3.1±0.0%, °Brix=11.0±0.1%, TSS=13.3±0.0%, µ=1288.0±20.1 cP, z=-13.3±0.3 mV and Log CFU/g=7.8±0.5. The probiotic microorganism Lb. casei ATCC 393 presents an adaptability in suspensions based on BC and inulin, which guarantee its viability and a possible use for obtaining an innovative spray-dried product.

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