Natural Freezing-Thawing and Its Impact on Dewaterability and Anaerobic Digestibility of Biosludge

2017 ◽  
Vol 34 (5) ◽  
pp. 357-366 ◽  
Author(s):  
Torsten Meyer ◽  
Xu Chen ◽  
Honghi N. Tran ◽  
D. Grant Allen ◽  
Elizabeth A. Edwards
Keyword(s):  
Anaerobic Digestibility ◽  
Natural Freezing

scholarly journals Microwave and Ultrasound Based Methods in Sludge Treatment: A Review

2021 ◽  
Vol 11 (15) ◽  
pp. 7067
Author(s):  
Zoltán Jákói ◽  
Balázs Lemmer ◽  
Cecilia Hodúr ◽  
Sándor Beszédes
Keyword(s):  
Wastewater Sludge ◽  
Process Efficiency ◽  
H2o2 Treatment ◽  
Treatment Conditions ◽  
Appropriate Treatment ◽  
Scientific Papers ◽  
Health Related ◽  
Scientific Results ◽  
Treatment Procedures ◽  
Anaerobic Digestibility

The amount of waste activated sludge (WAS) is increasing annually, and since it presents potential environmental and health-related risks, an appropriate treatment and stabilization process is needed. It has been shown in numerous studies in the past few decades that amongst the advanced treatment methods of sludge, microwave and ultrasound-based processes offer promising and effective alternatives. The main advantage of these physical methods is that they are energy-efficient, easy to implement and can be combined with other types of treatment procedures without major difficulties. In this review article we would like to present the recent scientific results of the microwave, ultrasound and combined (microwave-alkaline, microwave-H2O2, ultrasound-alkaline and ultrasound-H2O2) treatment of wastewater sludge, in terms of different process-efficiency indicators. Although the obtained results somewhat vary between the different scientific papers, it can be undoubtedly stated that both MW and US—either individually or in combination with chemical treatments—can enhance several aspects of sludge processing, like increasing the SCOD/TCOD rate, disintegration degree (DD), or the anaerobic digestibility (AD), but the extent of these increments clearly depends on the treatment conditions or parameters.

Mechanical freezing of alum sludge

1994 ◽  
Vol 30 (8) ◽  
pp. 177-184 ◽  
Author(s):  
C. James Martel
Keyword(s):  
Thin Layer ◽  
Basic Concept ◽  
Thin Layers ◽  
Ice Crystals ◽  
Patent Office ◽  
Operational Parameters ◽  
Average Production ◽  
Alum Sludge ◽  
Natural Freezing ◽  
The U.S

This paper presents a new mechanical freezing concept for freezing alum or other hydroxide sludges as a conditioning step for dewatering. The basic concept is to freeze a thin layer of sludge on a continuously moving fabric belt. Sludge is attached to the belt by a vacuum drum belt filter which also removes one-half of the water and thus reduces the amount of sludge to be frozen. Filter leaf tests were conducted to determine the operational parameters and approximate production rates of this concept. These tests show that freezing alum sludge in thin layers will separate out the water as ice crystals and transform the solids into the same type of granular material produced in natural freezing beds. The average production rate of frozen sludge was 6.5 kg/hr.m2 at −20°C. The belt area needed for a 10,000-m3/day plant was estimated to be 48 m2. This concept has been patented by the U.S. Patent Office.

Natural freezing survival by painted turtles Chrysemys picta marginata and C. picta bellii

1992 ◽  
Vol 262 (3) ◽  
pp. R530-R537 ◽  
Author(s):  
T. A. Churchill ◽  
K. B. Storey
Keyword(s):  
Freeze Tolerance ◽  
Chrysemys Picta ◽  
Painted Turtle ◽  
Survival Times ◽  
Painted Turtles ◽  
Ice Content ◽  
Total Body ◽  
Natural Freezing ◽  
Free Amino Acid Pools ◽  
Continuous Freezing

Hatchlings of both the Midland (Chrysemys picta marginata) and Western (C. picta bellii) subspecies of the painted turtle tolerate the freezing of extracellular body fluids while overwintering in terrestrial nests. Fall-collected hatchlings survived 3 days of continuous freezing at -2.5 degrees C, with ice contents of 43.5 +/- 1.0% of total body water (SE; n = 24) for C. picta marginata and 46.5 +/- 0.8% (n = 32) for C. picta bellii. Survival times dropped to 4-5 h when temperature was lowered to -4 degrees C, correlated with ice contents of greater than or equal to 50%. However, C. picta marginata tested immediately after excavation from nests in the spring showed greater freeze tolerance, with survival extending to 11 days at -2.5 degrees C and a higher mean ice content of 50.2 +/- 1.2% (n = 6). Spring hatchlings also had high supercooling points, -1.07 +/- 0.13 degrees C (n = 8), that dropped within 3 days to -4.83 +/- 0.83 degrees C (n = 4), suggesting a breakdown of endogenous ice-nucleating agents when hibernation ended. A search for possible cryoprotectants showed that both subspecies accumulated glucose and lactate in liver during freezing (net increase = 3-13 mumols/g wet wt); both also maintained large free amino acid pools in organs, with taurine making up 21-47% of the total.

scholarly journals Utilization of Dynamic and Physical Properties of Ice in Underground Mining Operations

1977 ◽  
Vol 19 (81) ◽  
pp. 672 ◽  
Author(s):  
Henning Fangel
Keyword(s):  
Underground Mining ◽  
Complete Recovery ◽  
Extraction Process ◽  
Wall Material ◽  
Mining Operations ◽  
Left Behind ◽  
Winter Temperatures ◽  
Extraction Processes ◽  
Natural Freezing ◽  
Lateral Walls

Abstract In sub-level caving mining operations, the lateral walls cave in. This results in dilution of the mineral content of the produced ore by 15%-20% waste rock. Also 15%-20% of the valuable ores are lost in the caved wall material that is left behind in the mined-out rooms. Placing ice, in the form of a small glacier, in the mine-room before the lateral walls start to cave, permit complete recovery of ore reserves without dilution. The glacier will advance at a rate permitted by ore extraction processes, in accordance with glaciological theories and laws. Volumes of ice that are required may be calculated from ore extraction rates, power consumed in the mine, ventilating air volumes and temperatures, specific heat and thermal conductivity of the lateral rock. The required ice volumes can be produced through natural freezing of water, where the winter temperatures regularly fall below 0°C for a predictable period every winter. Use of ice as a mining aid reduces costs of the ore extraction process by about one-third and increases value of the produced ore by about 20%. Thus, the value of a given orebody is increased by about 30% relative to the values experienced in the most efficient mines of today.

scholarly journals Impact of ozone assisted ultrasonication pre-treatment on anaerobic digestibility of sewage sludge

2015 ◽  
Vol 33 ◽  
pp. 29-38 ◽  
Author(s):  
Xinbo Tian ◽  
Antoine Prandota Trzcinski ◽  
Li Leonard Lin ◽  
Wun Jern Ng
Keyword(s):  
Sewage Sludge ◽  
Pre Treatment ◽  
Anaerobic Digestibility

Anaerobic digestibility of two processed municipal-solid-waste materials

Biomass ◽  
1990 ◽  
Vol 23 (3) ◽  
pp. 201-214 ◽  
Author(s):  
Christopher J. Rivard ◽  
Todd B. Vinzant ◽  
William S. Adney ◽  
Karel Grohmann ◽  
Michael E. Himmel
Keyword(s):  
Municipal Solid Waste ◽  
Solid Waste ◽  
Waste Materials ◽  
Anaerobic Digestibility

Desalination by natural freezing

Desalination ◽  
1973 ◽  
Vol 13 (2) ◽  
pp. 147-157 ◽  
Author(s):  
Phillip C. Wankat
Keyword(s):  
Natural Freezing

Anaerobic digestibility and fiber composition of bulrush in response to steam explosion

2010 ◽  
Vol 101 (17) ◽  
pp. 6610-6614 ◽  
Author(s):  
Jin Wang ◽  
Zheng-Bo Yue ◽  
Tian-Hu Chen ◽  
Shu-Chuan Peng ◽  
Han-Qing Yu ◽  
...  
Keyword(s):  
Steam Explosion ◽  
Fiber Composition ◽  
Anaerobic Digestibility
Sign in / Sign up

Export Citation Format

Share Document