Jaakko A Puhakka

Jaakko A Puhakka
Tampere University | UTA · Faculty of Engineering and Natural Sciences

Ph.D.

About

429
Publications
36,954
Reads
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8,972
Citations
Introduction
Environmental Engineering and Biotechnology Professor, Tampere University, FINLAND
Additional affiliations
September 2018 - December 2018
Tampere University of Technology
Position
  • President
January 2015 - July 2017
University of Eastern Finland
Position
  • Academic Rector
January 2014 - December 2014
Tampere University of Technology
Position
  • Vice President
Education
January 1988 - April 1990
University of Helsinki
Field of study
  • General Microbiology

Publications

Publications (429)
Article
Full-text available
This study reports the tolerance of chemolithoautotrophic biotransformation of sulphurous compounds towards pulp and paper (P&P) mill wastewaters (primary filtrate of bleaching (PFB) and composite wastewater (WW)) and their constituents under haloalkaline conditions. The effects of organic compounds (methanol, acetate, D(+)-xylose, phenol and benze...
Article
Full-text available
This study reports the effects of metal extraction liquors that are used for production of electric vehicle batteries on biological iron and sulfur oxidation. These liquors include ammonium sulfate and organic solvent constituents, and thus are potentially or inhibitory for heap bioleaching microorganisms. The effects of the liquors and their poten...
Article
Full-text available
Successful heterotrophic bioleaching with high metal yields requires an efficient leaching agent production and minimization of secondary reactions such as precipitation of leached metals with growth medium components. In this study, the role of the secondary reactions on bioleaching of spent nickel-metal-hydride batteries was investigated. Substit...
Article
Full-text available
The aim of this study was to investigate the potential for elemental sulphur recovery from sulphurous solutions under aerobic and anoxic conditions by haloalkalophilic Thioalkalivibrio denitrificans at 0.8-19.6 g S2O32--S L-1 and 0.2-0.58 g NO2 L-1, respectively. The experiments were conducted as batch assays with haloalkaline (pH 10 and ≥ 14 g Na+...
Article
In the Seto Inland Sea, Japan, chemical oxygen demand has increased over recent decades, while average dissolved oxygen concentrations in the bottom water have increased. In this study, we investigated responses of organic carbon (OC) in hypoxic sediment to changes of redox conditions using experimental columns containing sediment and overlying wat...
Article
Full-text available
Concentrated sulphurous and saline streams, produced for example by pulp and paper and petrochemical industries, pose challenges for both environmental and processes management. In this study, the potential of biological recovery of S° from haloalkaline thiosulphate solution in a Thioalkalivibrio versutus amended continuous-flow fluidized bed biore...
Article
Acid mine drainage (AMD), generated in the active and abandoned mine sites, is characterized by low pH and high metal concentrations. One AMD treatment possibility is biologically oxidizing Fe²⁺ followed by precipitation through pH control. As compared to autotrophic iron oxidizing microbial community, a microbial community enriched in the presence...
Article
Gluconate is known to mediate metal leaching. However, during bioleaching by e.g., Gluconobacter oxydans, gluconate can be oxidized to 2-ketogluconate and 5-ketogluconate. The impact of bio-oxidation of gluconate on metal leaching has not been investigated. Therefore, the aim of this study was to investigate leaching of rare earth elements (REEs) a...
Article
Jarosite precipitates formed in iron oxidising bioreactors have been shown to harbour iron-oxidisers. The aim of this study was to develop an iron oxidising bioprocess where microorganisms are retained solely on biogenic jarosite particles. Based on preliminary experiments using a fluidised-bed bioreactor (FBR), the formed jarosite particles starte...
Article
Biotransformation of thiosulphate by Thioalkalivibrio versutus was studied under haloalkaline conditions (pH 10, 0.66-1.2 M Na⁺) using batch assays and modelling tools for possible sulphur recovery from haloalkaline industrial streams. The thiosulphate was fully biotransformed to sulphate or to sulphate and elemental sulphur at initial S2O3²⁻-S con...
Article
Start-up of bioelectrochemical systems (BESs) fed with brewery wastewater was compared at different adjusted anode potentials (-200 and 0 mV vs. Ag/AgCl) and external resistances (50 and 1000 Ω). Current generation stabilized faster with the external resistances (9 ± 3 and 1.70 ± 0.04 A/m3 with 50 and 1000 Ω, respectively), whilst significantly hig...
Article
This study reports effects of elevated pressures on the oxidation of a soluble ferrous iron and low-grade sulphidic ore as little is known about biological iron and sulphur oxidation under these conditions. Pressure effects were studied in a pressurised batch-operated stirred tank reactor using acidophilic enrichment cultures. The oxidation of solu...
Article
The aim of this study was to determine an optimal anode material for electricity production and COD removal from xylose containing synthetic wastewater in an up-flow microbial fuel cell (MFC), and assess its suitability for treatment of thermomechanical pulping (TMP) wastewater with an enrichment culture at 37 °C. The anode materials tested include...
Article
Fluidized bed reactors (FBR) are characterized by two-phase mixture of fluid and solid, in which the bed of solid particles is fluidized by means of downward or upward recirculation stream. FBRs are widely used for multiple environmental engineering solutions, such as wastewater treatment, as well as some industrial applications. FBR offers many be...
Article
This study demonstrates (bio)electrochemical tetrathionate (S4O62 −) degradation with simultaneous elemental copper recovery from simulated acidic mining water. The effect of applied external voltage on anodic tetrathionate removal, cathodic copper removal and current density was studied using two-chamber flow-through bioelectrochemical (MEC) and a...
Article
Starting up a microbial fuel cell (MFC) requires often a long-term culture enrichment period, which is a challenge after process upsets. The purpose of this study was to develop low cost storage for microbial fuel cell enrichment culture to enable prompt process recovery after upsets. Anolyte of an operating xylose-fed MFC was stored at different t...
Article
Aerobic wastewater management is energy intensive and thus anaerobic processes are of interest. In this study, a microbial fuel cell was used to produce electricity from xylose which is an important constituent of lignocellulosic waste. Hydraulic retention time (HRT) was optimized for the maximum power density by gradually decreasing the HRT from 3...
Article
The effect of poised anode potential on electricity production and tetrathionate degradation was studied in two-chamber flow-through electrochemical (ES) and bioelectrochemical systems (BES). The minimum anode potential (vs. Ag/AgCl) for positive current generation was 0.3 V in BES and 0.5 V in the abiotic ES. The anode potential required to obtain...
Article
In the present study, six process liquors (PL1 - PL6) originating from heap bioleaching of a complex sulphide ore were examined to reveal factors limiting microbial activity in the bioheaps. PL4 had the lowest iron oxidation activity even though its indigenous iron-oxidising community was diverse (Acidithiobacillus, Leptospirillum, Acidiferrobacter...
Article
Pyrometallurgical processes for sulfide concentrates produce slag waste materials that contain multiple metals as carry-over impurities. Varied quantities of the metal content can be solubilized from the slag through chemical acid leaching or bioleaching. In this study, copper smelter slags were leached with and without iron- and sulfur-oxidizing b...
Article
Slags from metallurgical processes represent a potential resource of metals but also waste materials that have not been successfully beneficiated to date. For this study, a bulk slag sample from a copper smelter was evaluated under chemical and bacterial leaching conditions to test the solubilization of Cu and Zn in acidic, sulfate-rich solutions....
Article
To prevent uncontrolled acidification of the environment, reduced inorganic sulfur compounds (RISCs) can be bioelectrochemically removed from water streams. The long-term stability of bioelectricity production from tetrathionate (S4O62-) was studied in highly acidic conditions (pH <2.5) in two-chamber fed-batch microbial fuel cells (MFCs). The maxi...
Article
In bioelectrochemical systems (BES), the catalytic activity of anaerobic microorganisms generates electrons at the anode which can be used, for example, for the production of electricity or chemical compounds. BES can be used for various purposes, including wastewater treatment, production of electricity, fuels and chemicals, biosensors, bioremedia...
Article
The purpose of this study was to assess the dissolution of Si, Fe, Cu and Zn from a smelter slag sample under acidic chemical and bacterial leaching conditions. The Cu-containing solid phases were Cu-sulfides (57% distribution), fayalite (18%) and metallic Cu (16%). Zn was mostly associated with fayalite, magnetite and Na-silicate phases (Σ94%). Tw...
Article
The results on the effects of different anode potentials on current densities, coulombic efficiencies and microbial communities are contradictory and have not been studied with xylose, an important constituent of lignocellulosic materials. In this study, the effects of different anode potentials (+0.2, 0 and -0.2V vs. Ag/AgCl) on current generation...
Article
Microbial oil production combined with wastewater management is one option for a more sustainable future. Micrographs of microbial cultures enriched from palm oil mill effluent (POME) showed lipid inclusion in the eukaryotic cells, indicating the cells can accumulate lipids. However, enriching the culture did not increase the total lipids. Therefor...
Article
Piggery wastewater is a potent nutrient source for microalgal lipid production. Wastewater has been usually sterilized when used for microalgal cultivation. This is uneconomical in large-scale applications. Therefore, lipid productivity of Chlorella vulgaris CY5 using sterilized and non-sterilized diluted anaerobically pretreated piggery wastewater...
Technical Report
Full-text available
Nitrogen released from explosives or from mining processes and ending up in the water system can have negative environmental effects. The report aims for improved understanding on the nitrogen issue in the extractive industry. Essential data on nitrogen compounds present in the environments of mines and quarries has been collected, and based on the...
Article
Copper and iron dissolution of Zijinshan low-grade copper sulfide ores was investigated in ore-packed columns. At 60°C and pH 1.0, 37.1 g Fe(III) L-1 permitted effective copper dissolution and inhibited the activity of iron-oxidizing microorganisms. At 30°C, microorganisms stimulated Fe(II) and pyrite oxidation, resulting in 85 and 54% of copper an...
Article
The aim of this study was to select a potential microalgal strain for lipid production and to examine the suitability of anaerobically treated piggery wastewater as a nutrient source for production of lipid-rich biomass with the selected microalga. Biomass and lipid productivity of three microalgal strains (Chlorella sorokiniana CY1, Chlorella vulg...
Article
Inorganic sulfur compounds, such as tetrathionate, are often present in mining process and waste waters. The biodegradation of tetrathionate was studied under acidic conditions in aerobic batch cultivations and in anaerobic anodes of two-chamber flow-through microbial fuel cells (MFCs). All four cultures originating from biohydrometallurgical proce...
Article
The dispersion of nitrogenous compounds and heavy metals into the environment is frequent during mining activities. The effects of nickel (Ni) and cobalt (Co) on denitrification of simulated mine waters were investigated in batch bioassays and fluidized-bed reactors (FBRs). At pH 7, batch tests revealed that Co did not exhibit inhibition on denitri...
Article
Mining often leads to nitrate and metal contamination of groundwater and water bodies. Denitrification of acidic water was investigated in two up-flow fluidized-bed reactors (FBR) and using batch assays. Bacterial communities were enriched on ethanol plus nitrate in the FBRs. Initially, the effects of temperature, low-pH and ethanol/nitrate on deni...
Article
UML based software design use is presented to implement a simulation environment. Simulation environment will be a software application which will provide a playground for researchers to simulate bioreactor experiments involving microbial species and predict the products of the experiment. Four subsystems namely: Feed system, Bioreactor system, Mic...
Article
Lipids in wastewaters are potential raw material for renewable diesel, but may complicate biological treatment of wastewaters. The lipid composition of palm oil mill effluent (POME), chemithermomechanical pulp mill (CTMP) wastewater and municipal wastewater (MWW) was studied with a combination of thin-layer chromatography and nuclear magnetic reson...
Article
Full-text available
The spreading of nitrogenous compounds into the environment is a common challenge during mining industries. Typical explosives used in mining are N-based compounds which lead to nitrogen contamination of groundwater and water bodies. In gold extraction, cyanide used as lixiviant is also another source of nitrogen pollution. The present work aims to...
Article
This study is prompted by the high leaching efficiency of Zijinshan copper bio-heap leaching industrial plant. Bioleaching columns with 100 mm diameter and 1 m height were used to investigate copper bioleaching at different operating conditions. Elevated temperature, high total Fe concentration and high acidity significantly increased copper leachi...
Data
Full-text available
An exoelectrogenic culture was enriched on 1.0 g/L xylose from a compost sample in two-chamber microbial fuel cells (MFCs). Electricity production was optimized by changing mixing type, external resistance, xylose concentration and pH. Furthermore, the changes in microbial communities after each optimization step were monitored with PCR-DGGE. Elect...
Article
Full-text available
Oxidative dissolution of chalcopyrite at ambient temperatures is generally slow and subject to passivation, posing a major challenge for developing bioleaching applications for this recalcitrant mineral. Chloride is known to enhance the chemical leaching of chalcopyrite, but much of this effect has been demonstrated at elevated temperatures. This s...
Article
Full-text available
Changes in temperature, pH, moisture, C/N ratio, and bacterial community were monitored in Istanbul full-scale composting plant. C/N ratio steadily decreased during composting and final mature compost products had a C/N ratio of less than 20. During the composting process, temperature was mostly above 55 °C and decreased to mesophilic conditions in...
Article
Conifer and birch pulp fermentation to hydrogen and methane was studied using dry and wet pulps with a compost enrichment culture at a pH range from 6 to 9. Hydrogen was produced at each pH, whilst methane was produced at all other pH values except pH 6 with dry conifer pulp and pH 9. Hydrogen and methane yields were generally higher with birch tha...
Conference Paper
Full-text available
BioelectroMET is a collaborative research project between Magneto special anodes (NL), MAST Carbon International ltd (UK), Centre de Recherche Public Henri Tudor (Lux), Universitat Jaume I (ES), Linnaeus University (SE), Tampere University of Technology (FI) and Wetsus, centre of excellence for sustainable water technology (NL). The project is fund...
Article
Full-text available
Anaerobic hydrogen producing mesophilic and thermophilic cultures were enriched and studied from an intermediate temperature (45 °C) hot spring sample. H2 production yields at 37 °C and 55 °C were highest at the initial pH of 6.5 and 7.5, respectively. Optimum glucose, iron and nickel concentrations were 9 g/l, 25 mg/l and 25 mg/l both at 37 °C and...
Conference Paper
Full-text available
Microalgae have high photosynthetic efficiencies, high growth rates, and no need for external organic carbon supply and are, therefore, promising feedstocks for biofuel and bioenergy (e.g. hydrogen, methane, ethanol and biodiesel) production. Carbon dioxide from industrial flue gases can be used as a carbon source to increase the efficiency of micr...
Article
Concentrated acid hydrolysis of cellulosic material results in high dissolution yields. In this study, the neutralization step of concentrated acid hydrolysate of conifer pulp was optimized. Dry conifer pulp hydrolysis with 55 % H(2)SO(4) at 45 °C for 2 h resulted in total sugar yields of 22.3-26.2 g/L. The neutralization step was optimized for sol...
Article
In this study, grass silage was used both as a source of bacteria and as a substrate for dark fermentative hydrogen production. Silage is produced by lactic acid fermentation controlled by end point pH (<4.0). In this study, the fermentation of silage was successfully continued and directed to hydrogen production by neutralizing the pH. Highest hyd...
Article
Full-text available
Mass culture of microalgae is a potential alternative to cultivation of terrestrial crops for bioenergy production.However, microalgae require nitrogen fertiliser in quantities much higher than plants, and this has important consequences for the energy balance of these systems. The effect of nitrogen fertiliser supplied to microalgal bubble column...
Article
Dark fermentative hydrogen production by a hot spring culture was studied from different sugars in batch assays and from xylose in continuous stirred tank reactor (CSTR) with on-line pH control. Batch assays yielded hydrogen in following order: xylose > arabinose > ribose > glucose. The highest hydrogen yield in batch assays was 0.71 mol H2/mol xyl...
Article
This review discusses anaerobic production of methane, hydrogen, ethanol, butanol and electricity from microalgal biomass. The amenability of microalgal biomass to these bioenergy conversion processes is compared with other aquatic and terrestrial biomass sources. The highest energy yields (kJg(-1)drywt. microalgal biomass) reported in the literatu...
Article
In the present work the microbial community of a low grade nickel ore demonstration-scale bioheap was examined under varying weather (outside air temperature between + 30 and − 39 °C) and operational conditions over a period of three years in Talvivaara, Finland. After the start-up of heap irrigation, oxidation of pyrrhotite and pyrite increased th...
Article
Full-text available
Chlorella vulgaris (a freshwater microalga) and Dunaliella tertiolecta (a marine microalga) were grown for bulk harvest, and their biomass was tested as feedstock for electricity production in cubic two-chamber microbial fuel cells (MFCs) at 37°C. The anode inoculum was anaerobic consortium from a municipal sewage sludge digester, enriched separate...
Article
The aim of this study was to test three flat-plate photobioreactor configurations for cultivation of marine green alga Dunaliella tertiolecta under non-axenic growth conditions and to characterize and quantify the associated bacteria. The photobioreactor cultivations were conducted using tap water-based media. Static mixers intended to enhance mixi...