scholarly journals Biotechnological Production of Polyhydroxyalkanoates: A Review on Trends and Latest Developments

2014 ◽  
Vol 2014 ◽  
pp. 1-18 ◽  
Author(s):  
Baljeet Singh Saharan ◽  
Anita Grewal ◽  
Pardeep Kumar
Keyword(s):  
Extracellular Polymeric Substances ◽  
Continuous Process ◽  
Industrial Effluents ◽  
Paper Mill ◽  
Integrated System ◽  
Ecological Niches ◽  
Pulp And Paper Mill ◽  
Biotechnological Production ◽  
Dairy Wastes ◽  
By Products

Polyhydroxyalkanoates (PHA) producers have been reported to reside at various ecological niches which are naturally or accidently exposed to high organic matter or growth limited conditions such as dairy wastes, hydrocarbon contaminated sites, pulp and paper mill wastes, agricultural wastes, activated sludges of treatment plants, rhizosphere, and industrial effluents. Few among them also produce extracellular by-products like rhamnolipids, extracellular polymeric substances, and biohydrogen gas. These sorts of microbes are industrially important candidates for the reason that they can use waste materials of different origin as substrate with simultaneous production of valuable bioproducts including PHA. Implementation of integrated system to separate their by-products (intracellular and extracellular) can be economical in regard to production. In this review, we have discussed various microorganisms dwelling at different environmental conditions which stimulate them to accumulate carbon as polyhydroxyalkanoates granules and factors influencing its production and composition. A brief aspect on metabolites which are produced concomitantly with PHA has also been discussed. In conclusion, exploring of capabilities like of dual production by microbes and use of wastes as renewable substrate under optimized cultural conditions either in batch or continuous process can cause deduction in present cost of bioplastic production from stored PHA granules.

scholarly journals Production of Biopolymer from Bacteria - A Review

2021 ◽  
Vol 8 (2) ◽  
pp. 91-96
Author(s):  
Ranganadha Reddy Aluru ◽  
Sravani Koyi ◽  
Sanjana Nalluru ◽  
Chandrasekhar Chanda
Keyword(s):  
Continuous Process ◽  
Industrial Effluents ◽  
Optimal Growth ◽  
Paper Mill ◽  
Growth Conditions ◽  
Integrated System ◽  
Pulp And Paper Mill ◽  
Dairy Wastes ◽  
Polymeric Compounds ◽  
By Products

Polyhydroxyalkanoates (PHA) producers have been found in a variety of ecological niche’s that are naturally or unintentionally exposed to high organic matter or growth limiting substances such as dairy wastes, hydrocarbon contaminated sites, pulp and paper mill wastes, agricultural wastes, activated sludges of treatment plants, rhizosphere, and industrial effluents. Few of them also create extracellular byproducts such as rhamnolipids, extracellular polymeric compounds, and biohydrogen gas. These microbes can use waste materials of various origin as substrates while producing valuable bioproducts such as PHB. As a result, these microbes are industrially important candidates for production; Implementation of an integrated system to separate their by-products (intracellular and extracellular) could be an economical method. In this study, we reviewed several microorganisms that live in diverse environmental situations and are stimulated to collect carbon as polyhydroxyalkanoates granules, as well as variables that influence their production and composition. Ultimately, the current cost of bioplastic manufacture from stored PHA granules can be decreased by investigating capabilities such as dual generation of microorganisms and utilization of wastes as renewable substrate under optimal growth conditions in either a batch or continuous process.

Options for the conversion of pulp and paper mill by-products in Western Canada

2018 ◽  
Vol 26 ◽  
pp. 83-92
Author(s):  
Maryam Akbari ◽  
Adetoyese Olajire Oyedun ◽  
Siddharth Jain ◽  
Amit Kumar
Keyword(s):  
Paper Mill ◽  
Pulp And Paper ◽  
Western Canada ◽  
Pulp And Paper Mill ◽  
By Products

Anaerobic treatment of pulp and paper mill effluents – status quo and new developments

2007 ◽  
Vol 55 (6) ◽  
pp. 223-230 ◽  
Author(s):  
Leo Habets ◽  
Willie Driessen
Keyword(s):  
Paper Industry ◽  
Industrial Effluents ◽  
Paper Mill ◽  
Anaerobic Treatment ◽  
Pulp And Paper ◽  
Pulp And Paper Mill ◽  
Widespread Application ◽  
Paper Mills ◽  
Paper Mill Effluents ◽  
Pre Treatment

Since the early 1980s, anaerobic treatment of industrial effluents has found widespread application in the pulp and paper industry. Over 200 installations are treating a large variety of different pulp and paper mill effluents. Amongst various anaerobic systems the UASB and IC are the most applied anaerobic reactor systems. Anaerobic treatment is well feasible for effluents originated from recycle paper mills, mechanical pulping (peroxide bleached), semi-chemical pulping and sulphite and kraft evaporator condensates. The advantages of anaerobic pre-treatment are (1) net production of renewable energy (biogas), (2) minimized bio-solids production, (3) minimal footprint and (4) reduced emission of greenhouse gases. Via in-line application of anaerobic treatment in closed circuits (paper kidney technology) further savings on cost of fresh water intake and effluent discharge levies are generated.

scholarly journals Viscosity dynamics and the production of extracellular polymeric substances and soluble microbial products during anaerobic digestion of pulp and paper mill wastewater sludges

2019 ◽  
Vol 43 (2) ◽  
pp. 283-291
Author(s):  
Eva-Maria Ekstrand ◽  
Bo H. Svensson ◽  
Luka Šafarič ◽  
Annika Björn
Keyword(s):  
Anaerobic Digestion ◽  
Extracellular Polymeric Substances ◽  
Paper Mill ◽  
Pulp And Paper ◽  
Organic Loading Rate ◽  
Foam Formation ◽  
Soluble Microbial Products ◽  
Pulp And Paper Mill ◽  
Sludge Bulking ◽  
Microbial Products

Abstract The production processes of the pulp and paper industry often run in campaigns, leading to large variations in the composition of wastewaters and waste sludges. During anaerobic digestion (AD) of these wastes, the viscosity or the production of extracellular polymeric substances (EPS) and soluble microbial products (SMP) may be affected, with the risk of foam formation, inefficient digester mixing or poor sludge dewaterability. The aim of this study was to investigate how viscosity and production of EPS and SMP during long-term AD of pulp and paper mill sludge is affected by changes in organic loading rate (OLR) and hydraulic retention time (HRT). Two mesophilic lab-scale continuous stirred tank reactors (CSTRs) were operated for 800 days (R1 and R2), initially digesting only fibre sludge, then co-digesting fibre sludge and activated sludge. The HRT was lowered, followed by an increase in the OLR. Reactor fluids were sampled once a month for rheological characterization and analysis of EPS and SMP. The production of the protein fraction of SMP was positively correlated to the OLR, implicating reduced effluent qualities at high OLR. EPS formation correlated with the magnesium content, and during sulphate deficiency, the production of EPS and SMP increased. At high levels of EPS and SMP, there was an increase in viscosity of the anaerobic sludges, and dewatering efficiency was reduced. In addition, increased viscosity and/or the production of EPS and SMP were important factors in sludge bulking and foam formation in the CSTRs. Sludge bulking was avoided by more frequent stirring.

Cellular biopolymers and molecular structure of a secondary pulp and paper mill sludge verified by spectroscopy and chemical extraction techniques

2010 ◽  
Vol 62 (12) ◽  
pp. 2846-2853 ◽  
Author(s):  
Maryam Edalatmanesh ◽  
Mohini Sain ◽  
Steven N. Liss
Keyword(s):  
Extracellular Polymeric Substances ◽  
Wood Fiber ◽  
Soxhlet Extraction ◽  
Paper Mill ◽  
Pulp And Paper ◽  
Chemical Extraction ◽  
Pulp And Paper Mill ◽  
First Order Kinetics ◽  
Secondary Sludge ◽  
Similar Chemical

For proper treatment, recycling, or disposal of the pulp and paper mill secondary sludge qualitative and quantitative determination of its characteristics are necessary. Chemical extraction, quantitative characterization, and spectroscopic experiments have been performed to determine the molecular composition and chemical functionality of a pulp and paper mill secondary sludge. In order to extract the low-molecular-weight substances, soxhlet extraction with polar and non-polar solvents was performed where most of the target substances (17 ± 1.3%.) were extracted after 2 hours. Over time, this extraction followed a first-order kinetics. Fiber analyses have shown 12 ± 3% lignin, 28 ± 3% cellulose, and 12 ± 4% hemicelluloses content. The ash content was about 17 ± 0.5%. In this work, 7 and 16% intra- and extracellular polymeric substances, respectively, were extracted from the secondary sludge. EPS and mixture of intra- and extracellular biopolymers have shown similar chemical functionalities. These analyses confirmed that the paper secondary sludge consisted mainly of wood fiber, i.e. lignocellulosic substances, along with proteins and polysaccharides originated from microorganisms.

scholarly journals Production of extracellular polymeric substances by isolate consortia obtained from mesophilic aerobic granules from the treatment of paper mill effluent

BioResources ◽  
2019 ◽  
Vol 14 (3) ◽  
pp. 5845-5861
Author(s):  
Natalino Perovano Filho ◽  
Ismarley Lage Horta Morais ◽  
Lívia Carneiro Fidélis Silva ◽  
Claudio Mudadu Silva ◽  
João Carlos Teixeira Dias ◽  
...  
Keyword(s):  
Extracellular Polymeric Substances ◽  
Granular Sludge ◽  
Industrial Effluents ◽  
Paper Mill ◽  
Aerobic Granular Sludge ◽  
Aerobic Granules ◽  
Granulation Process ◽  
Paper Mill Effluent ◽  
The Subject ◽  
The Relationship

Aerobic granules are large, compact microbial aggregates when compared to flocculent sludge, and they can be used in wastewater treatment. The application of aerobic granular sludge in bioreactors for the treatment of industrial effluents is still considered innovative and has been the subject of several recent studies. In the present study, 19 microbial isolates from mesophilic aerobic granules, obtained from a previous study, were evaluated in co-aggregation tests. The extracellular polymeric substances (EPS) produced, such as carbohydrates, proteins, and humic acids, were determined. The aim was to evaluate the relationship between the amount of EPS produced and the contribution of each isolate in the granulation process. The results of EPS production were used to analyze the polysaccharide / protein (PS / PN) ratio. The consortia with an absence of isolates 4, 8, 11, 14, 19, and 25 presented a PS / PN ratio <0.5. These isolates, identified as belonging to the genera Staphylococcus, Agrobacterium, Enterobacter, and Rhodococcus, were considered effective for the production and stability of the mesophilic aerobic granules.

Improvement of COD Elimination in Activated Sludge Treatment Plant for Pulp and Paper Mill Waste Waters

1988 ◽  
Vol 20 (1) ◽  
pp. 121-132 ◽  
Author(s):  
C. H. Möbius
Keyword(s):  
Activated Sludge ◽  
Treatment Plant ◽  
Industrial Effluents ◽  
Paper Mill ◽  
Operating Conditions ◽  
Waste Waters ◽  
Pulp And Paper Mill ◽  
Sludge Treatment ◽  
Paper Mill Waste ◽  
Mill Waste

In recent years, authorities have issued more stringent COD regulations for industrial effluents in addition to BOD limitations. Optimization of operation in the activated sludge treatment plant can be an effective way to meet those regulations without increasing treatment cost. A well dimensioned aerobic or anaerobic plus aerobic treatment plant for pulp or paper mill waste waters is capable of reducing BOD effluent concentrations to values below 25 mg/l. If the aerobic plant is just big enough to meet this limit, COD elimination will be found to be in a certain ratio to BOD elimination, which has become well known in recent years. If this COD elimination is not sufficient to meet official requirements for COD concentration in the effluent, improvement of COD elimination by optimizing the operating conditions of the activated sludge plant may be possible. Lowering BOD sludge loading and increasing hydraulic retention time to more than 8 hours generally are the ways to do this. Concentration of dissolved oxygen has no effect on COD elimination above 1 mg/l. The best COD elimination can be obtained in optimized aeration cascade reactors and two stage aeration reactors.

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