Simultaneous carbon reutilization for primary sludge and stable nitrite production in a hydrolytic acidification coupled with partial denitrification system to treat nitrate contaminant

Abstract The importance of phosphorus as a nutrient in the eutrophication of lakes and rivers has been well established (Fruh 1967). It has been shown in addition that a significant amount of this phosphorus arises from the discharge of treated and untreated municipal wastewater (Task Group Report 1967). Consequently, measures are being taken, notably in the Province of Ontario, for removal of phosphorus from wastewater by means of chemical precipitation. Chemicals exhibiting satisfactory phosphorus removal include lime, iron compounds and aluminum compounds (Leckie and Stumm 1970; Schmid 1968; Wuhrman 1968).

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Reuse of Sludge from Pulp and Paper Industry Pilot and Full Scale Applications

Water Science & Technology ◽

10.2166/wst.1993.0069 ◽

1993 ◽

Vol 28 (2) ◽

pp. 17-26 ◽

Cited By ~ 6

Author(s):

V. Eroǧlu ◽

A. M. Saatçi

Keyword(s):

Economic Analysis ◽

Paper Industry ◽

Pulp And Paper Industry ◽

Pulp And Paper ◽

Full Scale ◽

Primary Sludge ◽

Recent Advances ◽

Made In

Recent advances made in the reuse of pulp and paper industry sludges in hardboard production are explained. Data obtained from pilot and full-scale plants using primary sludge of a pulp and paper industry as an additive in the production of hardboard is presented. An economic analysis of the reuse of pulp and paper primary sludge in hardboard manufacturing is given. The quality of the hardboard produced is tested and compared with the qualities of the hardboard produced by the same plant before the addition of primary sludge. The hardboard with primary sludge additive has been used in Turkey for about a year in the manufacturing of office and home furniture. The results are very satisfactory when the primary sludge is used at 1/4 ratio.

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Biosludge Incineration in a Recovery Boiler

Water Science & Technology ◽

10.2166/wst.1999.0712 ◽

1999 ◽

Vol 40 (11-12) ◽

pp. 195-200 ◽

Cited By ~ 6

Author(s):

P. Harila ◽

V.-A. Kivilinna

Keyword(s):

Black Liquor ◽

Pulp Mill ◽

Effluent Treatment ◽

Attractive Alternative ◽

Net Energy ◽

High Moisture ◽

Primary Sludge ◽

Start Up ◽

Combustion Emissions ◽

Recovery Boiler

An activated sludge process is an effective tool against effluent emissions in a pulp mill. It has only a few features which can be regarded deficiences. One of them is that effluent treatment of a modern pulp mill creates some 10-20 tonnes dry solids of biosludge per day. This sludge is difficult to burn due to its high moisture content. The most common way is to mix biosludge with primary sludge, to dewater the mixture in presses and finally to burn it in a solid fuel boiler. This type of sludge treatment incurs rather high costs and does not produce any net energy. Also combustion emissions vary depending on the boiler type. The Metsä-Botnia Kemi Pulp Mill was the first mill in the world to burn biosludge in a recovery boiler. The system start-up was in 1993 and it has been in operation ever since. Mechanically dewatered biosludge is mixed with weak black liquor and concentrated in a conventional evaporation plant equipped with a pressurized superconcentrator unit. In a modern recovery boiler, firing conditions are well controlled and monitored. Better emission control than in most bark fired boilers is achieved. Accumulation of nonprocess elements, corrosion, plugging, scaling and some other operational problems were expected. A lot of experience has been gathered during the years of operation and reviewed in this presentation. The achieved benefits of the system are discussed. Disposal of biosludge in a recovery boiler offers an economically and environmentally attractive alternative. Probably the best evidence from this is the fact that Metsä-Botnia has applied the same process solution in the recent reconstruction of the recovery departments at the Jouteno Mill.

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Organic matter release from primary sludge by mechanical cutting

Journal of Water Process Engineering ◽

10.1016/j.jwpe.2020.101896 ◽

2021 ◽

Vol 40 ◽

pp. 101896

Author(s):

Xianbao Wang ◽

Tiantian Chen ◽

Xuefei Qi ◽

Yudi Zhang ◽

Chuyue Gao ◽

...

Keyword(s):

Organic Matter ◽

Primary Sludge ◽

Mechanical Cutting

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Differential Effects of Toll-Like Receptor Activation and Differential Mediation by MAP Kinases of Immune Responses in Microglial Cells

Cellular and Molecular Neurobiology ◽

10.1007/s10571-021-01127-x ◽

2021 ◽

Author(s):

Jaedeok Kwon ◽

Christos Arsenis ◽

Maria Suessmilch ◽

Alison McColl ◽

Jonathan Cavanagh ◽

...

Keyword(s):

Map Kinase ◽

Microglial Activation ◽

Map Kinases ◽

Mrna Level ◽

Cell Types ◽

Receptor Activation ◽

Microglial Cells ◽

Toll Like Receptor ◽

Disease States ◽

Nitrite Production

AbstractMicroglial activation is believed to play a role in many psychiatric and neurodegenerative diseases. Based largely on evidence from other cell types, it is widely thought that MAP kinase (ERK, JNK and p38) signalling pathways contribute strongly to microglial activation following immune stimuli acting on toll-like receptor (TLR) 3 or TLR4. We report here that exposure of SimA9 mouse microglial cell line to immune mimetics stimulating TLR4 (lipopolysaccharide—LPS) or TLR7/8 (resiquimod/R848), results in marked MAP kinase activation, followed by induction of nitric oxide synthase, and various cytokines/chemokines. However, in contrast to TLR4 or TLR7/8 stimulation, very few effects of TLR3 stimulation by poly-inosine/cytidine (polyI:C) were detected. Induction of chemokines/cytokines at the mRNA level by LPS and resiquimod were, in general, only marginally affected by MAP kinase inhibition, and expression of TNF, Ccl2 and Ccl5 mRNAs, along with nitrite production, were enhanced by p38 inhibition in a stimulus-specific manner. Selective JNK inhibition enhanced Ccl2 and Ccl5 release. Many distinct responses to stimulation of TLR4 and TLR7 were observed, with JNK mediating TNF protein induction by the latter but not the former, and suppressing Ccl5 release by the former but not the latter. These data reveal complex modulation by MAP kinases of microglial responses to immune challenge, including a dampening of some responses. They demonstrate that abnormal levels of JNK or p38 signalling in microglial cells will perturb their profile of cytokine and chemokine release, potentially contributing to abnormal inflammatory patterns in CNS disease states.

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Sulfite pretreatment enhances the biodegradability of primary sludge and waste activated sludge towards cost-effective and carbon-neutral sludge treatment

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.146634 ◽

2021 ◽

pp. 146634

Author(s):

Feixiang Zan ◽

Hao Huang ◽

Gang Guo ◽

Guanghao Chen

Keyword(s):

Activated Sludge ◽

Cost Effective ◽

Waste Activated Sludge ◽

Sludge Treatment ◽

Primary Sludge ◽

Carbon Neutral

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Evidence for enhanced eNOS function in coronary microvessels during the second window of protection

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00326.2006 ◽

2007 ◽

Vol 292 (5) ◽

pp. H2152-H2158 ◽

Cited By ~ 11

Author(s):

Song-Jung Kim ◽

Xiaoping Zhang ◽

Xiaobin Xu ◽

Alice Chen ◽

Joaquin B. Gonzalez ◽

...

Keyword(s):

Ace Inhibitors ◽

Calcium Ionophore ◽

Left Ventricular ◽

Wall Thickening ◽

No Production ◽

Ionophore A23187 ◽

Nitrite Production ◽

Hoe 140 ◽

Enos Protein ◽

Second Window Of Protection

Nitric oxide (NO) derived from endothelial NO synthase (NOS) (eNOS) has been identified as a trigger for the second window of protection (SWOP), but its role as a mediator during the SWOP is a matter of debate. Eighteen mongrel dogs were chronically instrumented to measure left ventricular function, coronary blood flow, and wall thickening. Myocardial preconditioning was induced by 10 min coronary artery occlusion. After 24 h of reperfusion (during the SWOP), the hearts were excised. Coronary microvessels were isolated and incubated in presence of 1) the endothelium-dependent agonists carbachol and bradykinin, 2) the calcium ionophore A23187, and 3) the angiotensin-converting enzyme (ACE) inhibitors enalaprilat and ramiprilat. Nitrite, a metabolite of NO, was measured. Under baseline conditions, nitrite production in microvessels from SWOP was 30% higher than that from normal (96 ± 4 vs. 74 ± 3 pmol/mg, P < 0.01, respectively). Nitrite production in response to carbachol, bradykinin, and A23187 was also enhanced in microvessels from SWOP ( P < 0.05). These enhanced responses were abolished by NG-nitro-l-arginine methyl ester (l-NAME) or the endothelial receptor-specific antagonists atropine and HOE-140. The level of eNOS protein in the SWOP myocardium was twofold higher than that in the non-SWOP myocardium. Nitrite production in response to the ACE inhibitors was greater in microvessels from SWOP. These effects were blocked by l-NAME, HOE-140, or dichloroisocoumarin (which inhibits kinin formation). We found that a brief ischemic episode induced delayed, enhanced NO production in coronary microvessels and an upregulation of eNOS protein. These findings suggest that eNOS is a mediator during the SWOP. The ability of ACE inhibitors to enhance NO release during the SWOP points to an additional clinical application for these drugs.

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