New Role of Sulfuric Acid
In Production of Multicomponent Fertilizers From
American Journal of Agricultural and Biological Sciences
process in the food and agriculture industry has an
impact on the environment and there is much concern
about environmental pollution.
Branches of industry produce wastes of different
quality and quantity, which, if not treated, could lead
to increasing disposal problems and severe pollution.
Agricultural and food industry systems generate
by-products, wastes and air emissions with possible
impact on the environment
. Waste resources include wood and wood wastes,
agricultural crops and their waste by products,municipal
solid wastes (MSW), animal wastes,wastes from food
processing, aquatic plants and algae.
. Utilization of
various organic wastes in agriculture (e.g. as a
fertilizers) depends on several factors, including the
characteristics of the waste such as nutrient and heavy
metal content, energetic value, odor generated by the
waste, availability and transportation costs, benefits
to agriculture, and regulatory considerations.
. Application of wood ashes, feather, bones and
litter in agriculture (e.g. fertilizers production) is a
way to recycle nutrients and to limit consumption of
Large livestock and poultry farms produce considerable
quantities of wastes – renewable sources of nutrients.
A part of the wastes is directly applied into the soil,
producing leachates witch contaminate ground waters.
Using the waste as a raw material for biofertilizers
would be a sustainable alternative.
Recently, a number of
States in the USA and several countries in Europe are
considering the collection, processing, and re-use of
waste in order to increase the amount of materials
recycled and to reduce the amount of organic matter
reaching final disposal sites.
The main goal is to make
the “waste” a renewable resource that can be utilized
and not discarded.
In the literature it is
reported that organic wastes could be re-used (1) as
fertilizers and soil amendments, (2) in the processes of
energy recovery (heat, liquid fuels, electricity)[2-4],
and (3) in the production of chemicals (volatile organic
acids, ammonium products, alcohols).
technologies for utilizing wastes could be classified
into four categories: direct combustion, thermochemical
processes, biochemicalprocesses and agrochemical
processes . The first method - direct combustion is
the easiest and the mostly popular. Ashes – the waste
product from combustion are proposed to be used as
MATERIALS AND METHODS
Studied material: Poultry feather, animal bones
and wood for the combustion originated from Lower
Silesia region in south-west Poland (high capacity of
metallurgy industry – copper industry). Sulfuric acid
used for mineralization of slaughter wastes was from
POCH S.A. Gliwice.
Analytical methods: The basic components of NPK
fertilizer: P2O5, K2O and micronutrients, and N were
determined by colorimetric analysis, ICP-AES method and
Kjeldahl method, respectively.
Mercury was analyzed with Mercury analyzer AMA 254
atomic absorption spectrometry. The samples were
mineralized with concentrated mineral acids of supra
pure grade (from Merck) according to the procedure
described previously in a microwave oven (type
Milestone MLS-1200 MEGA ).
The solution after cooling was filtered trough medium
paper filter and diluted with demineralized water to the
volume 75 ml. The solution was analyzed in three repeats
by ICP-OES and ICPMS to determine the concentration
of metal ions (Al,As, B, Ca, Cd, K, Mg, Na, Pb, Zn). For
the preparation of standard solution (1.0, 10, 100
mg.l-1) the multielemental standard was used (UltraScientific
Mercury was analyzed with Mercury analyzer AMA 254
atomic absorption spectrometry (Czech Republic ).
Sulphur was determined by ICPOES .
Determination of total nitrogen: The total
nitrogen content was determined by the Kjeldahl
method. The method consists of three basic steps: 1)
digestion of the sample (0.2 g of solution after
digestion of feathers) in 20 ml sulfuric acid (95 %)
with a catalyst (K2SO4 and CuSO4 in the ratio 20:1),
which resulted in conversion of nitrogen to ammo nia;
2) distillation - after addition of the base(NaOH), the
ammonia was distilled from an alkaline medium and
absorbed in boric acid and 3) determination of ammonia
by titration with a standard solution (0.1 mol.l-1) HCl.
For the determination of nitrogen, digestion apparatus (Büchi
Digestion Unit K-424) and distillation apparatus (Büchi
Distillation Unit B-324) were used.
RESULTS AND DISCUSSION
New standards of organization of wastes disposal and
management in developed countries enforce on industry,
in particular agricultural food industry with the
particular consideration of slaughterhouses and
implementation of new technological solutions which will
enable wastes utilization with recovery of fertilizer
This idea enables not only to avoid problems with wastes
but simultaneously gives the possibility to save money
on import of expensive fertilizer raw materials (natural
gas, phosphate raw materials,potassium salts). In this
paper, we propose a special solution of using the
properties of sulfuric acid for the digestion of poultry
feather and cattle, swine and poultry bones.
Taking into account the content of nitrogen in keratin
substances (feather), phosphorus (bones) and wood ash
(potassium, calcium, magnesium), we have the possibility
of composing various complex fertilizers dedicated for
special fertilization purposes – potatoes,sugar beets,
maize crops and special vegetables according to
The content of micronutrients, micronutrienta and
undesirable elements in various renewable resources was
The average results of measurements of N=6 samples are
presented in Table 1, 2 and 3, that show the content of
the main fertilizer nutrients, micronutrients and other
elements, in particular, four elements (Pb, As, Hg and
Cd) the content of which is limited by fertilizer
recommendations is presented.
The samples originated from the region of Lower Silesia
in which non-ferrous metallurgical industry is
As an example of preparation of mineral-organic
fertilizer produced by the utilization of the renewable
sources, the new fertilizer technology solution is
presented for obtaining the suspension NPKS fertilizer
for nutrition of oil seed rape.
This fertilizer can be obtained using poultry feather as
the raw material,sulfuric acid, potassium carbonate and
non-litter poultry manure. We present a procedure
directed to fertilization of 1 ha arable land for the
cultivation of oil seed grain.
The new type of fertilizer was composed of the liquid
product of mineralization of poultry feathers by
sulfuric acid (A) and crude non-litter poultry husbandry
manure (B).The component (A) was prepared by
mineralization of 1125 kg of poultry feathers by 2025 kg
of 60 % sulfuric acid in the temperature 85-90 oC during
4 hours of retention time.
During the process of acidic digestion, protein-nitrogen
from keratin is decomposed into ammonia form of nitrogen
which is bioavailable to plants.
The post-reaction liquid product was partially
neutralized by the addition of 1.863 kg K2CO3. According
to the agricultural recommendations for oil seed rape
nutrition, we added 13.5 kg of sodium borate Na2B4O7*10
H2O (borax) and 5.22 kg of manganese sulfate monohydrate
MnSO4*H2O as necessary micronutrients.The composition of
the obtained product, NPKS fertilizer component.
Presented technological solution of utilization of
renewable source of fertilizer nutrients enable to
protect environment from undesirable emissions of
ammonia and sulphur volatile organic compounds. Such a
solution should enable to reduce many times (8-10)
emission of odor gases .
This concept and new technological solution is the aim
of development project with the co-operation with large
poultry slaughterhouse with daily production 7-10Mg of
waste poultry feather. The obtained fertilizer will be
used in local farms. The process is going to be
implemented on technical scale.