Removal of heavy metals and phosphates from

wastewater by bioparticles.

The 2nd International Symposium “Vera Johanides” BIOTECHNOLOGY IN CROATIA BY 2020

Zagreb, 10 – 11 May, 2013

Lucija Nuskern, mag. oecol.Jasna Hrenović, PhD

1. IntroductionNeed for wastewater treatment prior to

release into receiving environment◦Heavy metals – toxic activity, bioacumulation◦Phosphates – eutrophication

BIOPARTICLE – particle composed of inorganic carrier and biofilm of bacteria◦higher density of bacterial population,

bacteria protected from biotic and abiotic stresses, no bacterial wash-off better treatment efficiency

Aim of the studyDesign bioparticles able to:

1) tolerate exposure to high concentrations of Cu2+, Zn2+ and Ni2+

2) Simultaneously remove those heavy metals and phosphates (PO4

3-) from wastewater

2. Materials and methodsNatural zeolitic tuff (Vranjska Banja,

Srbija) – carrier material

Bacteria: Acinetobacter junii DSM 1531 ◦ P - accumulationPseudomonas aeruginosa DSM 15980◦ Heavy metal tolerance

Mineral composition (wt %): clinoptilolite (72.6), plagioclase (14.6), quartz (12.8)

Particle size: 0.063 – 0.121 mm

Bacterial immobilisationIncubation of zeolitic tuff with

pure bacterial culture of A. junii or P. aeruginosa in liquid medium, 24 h/30 °C with aeration

Wet bioparticles with immobilised A. junii

(AJBP)

Wet bioparticles with immobilised P.

aeruginosa

(PABP)

Experimental procedure1. Planctonic bacteria

2. Immobilised bacteria (bioparticles - BP)

1 mLA. junii or

P. aeruginosa

C1 – C5:1, 5, 10, 25 and 50 mg Cu2+/L1, 5, 10, 35 and 70 mg Zn2+/L1, 5, 10, 25 and 50 mg Ni2+/L

100 mL P -

medium+

1 g wet AJBP or PABP

100 mL P -

medium+

C1, C3 and C5:1, 10 and 50 mg Cu2+/L1, 10 and 70 mg Zn2+/L1, 10 and 50 mg Ni2+/L

Experimental procedure 3. Mixed AJBP and PABP in synthetic wastewater

4. Mixed AJBP and PABP in real wastewater

0.5 g wet AJBP and0.5 g wet

PABP

100 mL P -

medium+

0.5 g wet AJBP and0.5 g wet

PABP

100 mL efluent +

C1, C3 and C5:1, 10 and 50 mg Cu2+/L1, 10 and 70 mg Zn2+/L1, 10 and 50 mg Ni2+/L

C1, C3 and C5:1, 10 and 50 mg Cu2+/L1, 10 and 70 mg Zn2+/L1, 10 and 50 mg Ni2+/L

3. RESULTS - Heavy metal tolerance PLANCTONIC vs. IMMOBILISED bacteria

Control C1 C3 C50.02.04.06.08.0

10.0Planctonic Immobilised

c (Cu2+)/ mg dm-3

log

CFU

Control C1 C3 C50.02.04.06.08.0

10.0

c (Zn2+)/ mg dm-3

log

CFU

Control C1 C3 C50.02.04.06.08.0

10.0

c (Ni2+)/ mg dm-3

log

CFU

A. junii

Control C1 C3 C50.02.04.06.08.0

10.0Planctonic Immobilised

c (Cu2+)/ mg dm-3

log

CFU

P. aeruginosa

Control C1 C3 C50.02.04.06.08.0

10.0

c (Zn2+)/ mg dm-3

log

CFU

Control C1 C3 C50.02.04.06.08.0

10.0

c (Ni2+)/ mg dm-3

log

CFU

3. RESULTS - Heavy metal removal PLANCTONIC vs. IMMOBILISED

bacteria

Highest heavy metal removal was achieved with PABP: 84,1 % Cu2+, 100 % Zn2+ and 83,7 % Ni2+

C1 C3 C50.020.040.060.080.0

100.0Cu, PABP % Cu removed planctonic

% Cu removed immobilised

% C

u2+

rem

oval

C1 C3 C50.020.040.060.080.0

100.0Zn, PABP % Zn removed planctonic

% Z

n2+

rem

oval

C1 C3 C50.020.040.060.080.0

100.0Ni, PABP % Ni removed planctonic

% Ni removed immobilised%

Ni2

+ r

emov

al

3. RESULTSMixed AJBP and PABP in real wastewater

AJBP and PABP survived, multiplied and removed heavy metals and phosphates when in the same system

Control C1 C3 C50.0

20.040.060.080.0

100.0

Cu

P in P-medium P in efluentCu in P-medium Cu in efluent

% r

emov

ed

Control C1 C3 C50.0

20.040.060.080.0

100.0Zn

P in P-medium P in efluentZn in P-medium Zn in efluent

% r

emov

ed

Mixed AJBP and PABP removed heavy metals and phosphates from real wastewater more efficiently than from synthetic wastewater

4. CONCLUSION

Bioparticles composed of immobilised bacteria A. junii and P. aeruginosa on natural zeolitic tuff could be used to simultaneously remove heavy metals and phosphates from wastewater

THANK YOU FOR YOUR ATTENTION!