Principles of Municipal Sewage Sludge Bioconversion into Biomineral Fertilizer

The efficiency of heavy metals removal from sewage 
sludge in bioleaching processes with heterotrophic, chemoautotrophic 
(sulphur-oxidizing) sludge cenoses and chemical leaching (in 
distilled water, weakly acidic or alkaline medium) was compared. 
The efficacy of heavy metals removal from sewage sludge varies 
from 83 % (Zn) up to 14 % (Cr) and follows the order: Zn > Mn > Cu 
> Ni > Co > Pb > Cr. The advantages of metals bioleaching process 
at heterotrophic metabolism were shown. A new process for 
bioconversation of sewage sludge into fertilizer at middle 
temperatures after partial heavy metals removal was developed. This 
process is based on enhancing vital ability of heterotrophic 
microorganisms by adding easily metabolized nutrients and synthesis 
of metabolites by growing sludge cenoses. These metabolites possess 
the properties of heavy metals extractants and flocculants which 
provide the enhancement of sludge flocks sedimentation. The process 
results in biomineral fertilizer of prolonged action with immobilized 
sludge bioelements. The fertilizer satisfies the EU limits for the 
sewage sludge of agricultural utilization. High efficiency of the 
biomineral fertilizer obtained has been demonstrated in vegetation 
experiments.

• K. V. Kalinichenko
• G. N. Nikovskaya

• Fertilizer
• heavy metals
• leaching
• sewage sludge.

[1] P. A. Vesilind, and L. Spinosa, "Sludge production and characterization.
Production and regulations” in Sludge into Biosolids. Processing,
Disposal and Utilization, L. Spinosa, P. A. Vesilind, Ed. London: IWA
Publishing, 2001, pp 3–18.
[2] A. Berbecea, I. Radulov, and F. Sala, "Agricultural use of sewage sludge
pros and cons”, Research Journal of Agricultural, vol. 40, no. 2, pp. 15–
20, Apr. 2008.
[3] L. Constantinescu, "Fertilizing agricultural fields with the sludge
resulted from sewage water treatment stations”, Research Journal of
Agricultural, vol. 40, no. 2, pp. 41–44, Apr. 2008.
[4] G. N. Nikovskaya, K. V. Kalinichenko, and Z. R. Ulberg, "Changes in
the surface properties and stability of biocolloids of a sludge system
upon extraction of heavy metals,” Colloid Journal, vol. 75, no. 3, pp.
274–278, May-June 2013.
[5] G. N. Nikovskaya, K. V. Kalinichenko, and Y. P. Boyko, "The change
in activated sludge surface properties after heavy metals leaching”,
Journal of Water Chemistry and Technology, vol. 35, no. 4, pp. 177–
182, July 2013.
[6] G. N. Nikovskaya, K. V. Kalinichenko, and Z. R. Ulberg, "Heavy metals
in sludge sediment after biochemical purification of municipal
wastewaters”, Journal of Water Chemistry and Technology, vol. 33, no.
5, pp. 333–338, October 2011.
[7] G. N. Nikovskaya, Z. R. Ul’berg, and L. A. Koval’ "Colloidochemical
processes in biotechnology of heavy metal removal from the soil,”
Colloid Journal, vol. 63, no. 6, pp. 820–824, Nov.-Dec. 2001.
[8] L. Diels, M. De Smet, and L. Hooyberghs "Heavy metals bioremediation
of soil” Molecular Biotechnology, vol. 12, no. 2, pp. 149–158, June
1999.
[9] F. Shooner, and R. D. Tyagi, "Thermophilic microbial leaching of heavy
metals from municipal sludge using indigenous sulphur-oxidizing
microbiota”, Appl. Microbiol. Biotechnol., vol. 45, no. 3, pp. 440–446,
Apr. 1996.
[10] J.-Y. Wang, O. Stabnikova, S. T. L. Tay, V. Ivanov, and J.-H. Tay,
"Biotechnology of intensive aerobic conversion of sewage sludge and
food waste into fertilizer”, Water Sci. Technol., vol. 49, no. 10, pp. 147–
154, Oct. 2004.
[11] K. V. Kalinichenko, G. N. Nikovskaya, and Z. R. Ulberg "Bioextraction
of heavy metals from colloidal sludge systems”, Colloid Journal, vol.
74, no. 5, pp. 553–557, Sep.-Oct. 2012.
[12] G. N. Nikovskaya, Z. R. Ul’berg, E. N. Borisova, and A. G. Savkin,
"The influence of different reclamation agents and microorganisms on
the aggregative stability of the colloidal fraction of meadow chernozem
soil”, Colloid Journal, vol. 68, no. 3, pp. 345–349, May-June 2006.
[13] F. D. Dakora1, and D. A. Phillips, "Root exudates as mediators of
mineral acquisition in low-nutrient environments”, Plant and Soil, vol.
245, no. 1, pp. 35–47, Aug. 2002.