Note: Descriptions are shown in the official language in which they were submitted.
i77
P:ROCESS AND APPA.RAqUS FOR U~ILIZA~ION O~` PRODUCTS
OF VITAL AC~IVI~Y OF ANIMA3~S
~ he present invention relates to the process of treat-
ment of ~astes resulting from a~imal ~reeding such as m~nure,
vege-table remnants and mixtures thereof, as ~ell as to an
apparatus for performin~ this process~
'rhe process according to the present invention c~n be
used fOI- processing of` organic wastes resul-ting ~rom agricul-
tural producticn, mainly in animal breeding farms and in
other artificial ecological sys-tems with a closed circu.it of
~i.oconversion of nutrient subst~nces ~nd energy.
Known in the ar-t are a number of processes associated
with the -treatrnent of orga~ic wastes. These processes are
exempli~ied by such processes as manure compos~ing, aerobic
microbiological treatment, use of liquid manure lor irrigation
of ields, metl~ne fermen-tation; treatment by fly larvae, uti-
lization for fertilizers and/or as a ~eed stuf after a spe-
cial biochemical processing, alld the like
The basic requirement imposed on these processes under
commercial production conditions is -the possiblity of ob
taining the processing products (fertilizers or feedstuffs)
~,Ji~ ~,~jjt~D7
of a required quality at minimal losses of nutrient proper-
ties of manure, minimal rate of time- and money consumption
per unit of the final product.
Quality of the resulting products of such treatment is
defined b~ the degree of retention of that fertilizing ca-
pacity or protein content v~hich is characteristic o~ the start-
ing marlure1 and by the fulness of conversion of the nutrient sub-
stances contained therein to a feedstuff product ~egetable~
microbial or other protein-containing biomass).
To achieve the maximum value of this characteristic at
required process speed, it is necessary, first of all, to
nimize losses o-f ni-trogen and organic matter inavoidable
upon its uncontrollable decomposition v~hich is acco~panied
by an intensive dissipation of the volatile matters result-
ing frorn the decomposition of organics in the form of nitro-
en- and carbon-containing gases, as well as to ensure a ra-
id and e~ficient (from the economic standpoint) conversion
of the organic mass of manure to a feedstuff
Known process for treatment of products of vital activity
of animals feature different limiting speed and efficienc~
while the resulting products feature a aifferent degree of
compliance with the sanitary and zootechnical norms~ Ho~ever,
by the present moment none of these prior art pr~cesses satis~
fies adequately the requirements of intensified animal breed-
ing~ economic efficienc~ and environment protection. In this
respect, manure and manure liquids still remain one the main
- 4 -
sources of pollution of soil9 air and water basins in thearea of location of large-size animal-breeding farms and
enterprises~
~ he absence of suitable technological innovations in
the art of manure processing hampers a co~mercial-scale anlmal
breeding development and does not make it possible to intensify
the manufacture of animal-breeding products in compliance with
the modern requirements of economic ef~iciency, zoo-hygiene
and protection of the environments.
Particular advantages and drawbacks of the prior art pro-
cesses are demonstra-ted by modern technologies for processing
of animal-breeding wastes employed in large-size animal-breed-
ing farms and enterprises.
'~he principal process for treatment of liquid manure
is its utilization as an organic fertilizer. ~he most wide-
spread operation for its preconditioning before application
employed hitherto is keeping thereof in a system of basins
and a subsequent application onto soil by sprin~ling or
spraying. ~he basins are mainly arranged in the form of open-
settling ponds, wherein a biological degradation of a portion
of liquid manure and stall dung runoff ta~es place with the
formation of an organic fert~i~er sui~able ~or application.
In these ponds liquid manure is kept for quite a long
time (abou~ 100 days), aerated by means of statio~ary or
floating turbins; the solid fraction of manure settling onto
the pond bottom is cleaned-out once in two or three years~
5 --
r~his simple 3 th-~ugh extensive, method for m~nure processing
features considerable losses of nu~rient mattersO Losses
of ammonium nitrogen in a conventional aerobic pond are as
high as 90% of its initial content.
The aerobic fermentation stops at a temperature of e~en
~18~, wherefore during winter time such basins are mere dung
storesO They are unsatisfac-tory as regards -the sani-tary and
hygienic conditions due to the survival of salmonellae therein
at the above-mentioned temperature during the entire storage
period~
~ he basin-storage method is sometimes combined wi-th
the processing in a system of oxidation trenches. In oxida-
tion t'enches located under slit-perf'ora~ed floors of cattle
houses aerators are provided made as rota-ting wheels with
vanes ensuring agi-tation of the manure mass, saturation there-
of with oxygen and transpor-tation along a manure cha~lel. In
this method of manure processing an aerobic degradation occurs
even in the winter period~ though the speed of the process is
not high; the system of oxidation trenches necessitates high
capital investment and features great losses of nutrien-t mat-
ters f'rom manure. Among operation disadvantages of -this method
are: ~apid wear of the a~ration means and abundant foaming which
may even break through into the premises. ~his disadvantage,
in view of lack of adequately reliable modes of control under
these conditions, constitutes a serious technical problem.
It should be also noted that taking in~o consideration a high
- 6 - !
density of population in industrially developed countries7 an
essential disadvantage of all modifications of the basin-type
method of manure processing resides in the risk o~ pollution
of underground waters especially in the case of light soils,
an intensive odour evolu-tion, especially in spring~ as well
as -the necessity o~ using large areas o~ soil ~or the arrange-
ment of such basin~ or ponds.
Other methods for manure processing contemplating u~i-
lization thereof only for fex-tilizers are based on separation
of manure to the li~uid and solid fractions. ~he solid frac-
tion enriched with nutrient substances is stacked into stor-
age piles, -then dried or compos-ted and afterwards applied
onto the soil~
In general, separation into fractions makes it possib-
le to reduce the size and urli-t capacity of the equipment,
to shorten the duration of the subsequent processing of the
liquid phase; makes it also possible to use it in the return
cycle~ thus lowering the total wat_er consumption. ~owever,
this process has but a limited application, since it necessi-
tates vast soil area to ensure a harmless u-tilization o~ con-
siderable amounts of liquid manure by way of a direct i~t-
roduction thereof into the soil.
~ urthermore, as it is demonstrated by the available data
of agrochemical investigations, losses o~ ni-trogen and orga-
~ic compounds during the bio-thermal treatment upon compost-
ing axe ve~y high and in certain cases exceed 30% of their con-
-- 7
tent in the solid fraction. ~osses of nitrogen upon the di~
rect application of the liquid phase of manure in-to soil are
as high as 95% of its initial content.
Recently a method of aerobic -treatment o~ manure to
obtain fertilizers in sllo-type storage houses has acQuired
a large scale application In contrast -to the basin-type pro-
cess 9 liquid ~anure from the cattle house is no-t immedia-tely
pumped to the storage. ~irst of all, it is delivered into
one or several -tanks provided with aerators, wherein it is
kept for several days,gellerally 7-10 days. ~nder -the condi-
tions of aeration microorganism intensively degrade organic co-
mpounds and, as a result, the product temperature is increased-
to 42-65C. This causes desinfection of the mixture, whereaf-
ter liquid manure is pumped to the storage.
Transportation of manure to the field and application
onto the soil is effected by means of lar~e-size truck-tanks
provided with means for under-soil introduc-tion of man~e and
pumps ~his method makes it possible to reduce the -time of
treatment of manure to 7 days, i.e. it is the most intensive
among -the above-described prior art methodsO However, losses
o~ nutrient substances from manure still remain high (ammonia
nitrogen even at the sta~e o~ aeration is lost substantially
completely, while the content of organic compounds is reduced
by 50-55~0 due to biothermal degradation). ~he most efficient
irom the economic standpoint, as regards the conservation of
-- 8 --
the fertilizing capaci-t~ of manure and a re~uired degree o~
its desinfection, is the method of anaerobic (methane) fer-
mentation of manure in closed vessels.
In kno~un methane t~lks manure is kept at the temperature
of 56C for 25-28 days, ~hereafter it is transported to the
Yield or delivered to storage.
~ his method, however, features a disadvantage residing
in a high rate of power consum~tion associated with the ne-
cessity of maintaining thermophilic conditions in the reactor,
'lS causing, under -the above-mentioned ~ermentation condi-
ons and process duration, considerable power consump-tion
or necessitating consumption of a substan-tial portion of -the
evolving metharle-containing gas for heating of the methane
tank. As a result, at substantially total conservation of
ammonium ni-trogen, losses of the organic mat-ters in the form
of -the combusted bio-gas are as high as 30 '~0~0~
Furthermore, this process necessi-tates for its realiza-
tion considerable initial investments of capital and, for
this reason~ at low rates of anaerobic treatment it is genera-
lly non-profitable.
Another group of processes for utiliza-tion of wastes
resulting from animal breeding stipulates treatment thereof
with the production of not only organic fertilizers, but a
feedstuff protein as well. Direct processing of manure to
a feedstuff avoiding plant-growing makes it possible to sub-
_ g _
stantially reduce -the traditional cycle of bioconversion of
nutrient substances (constituting 3-4 years under natural
conditions) and ensures their return to the ~eedstuff within
several days~
Due to biological specificity of the alimentary tract of
animals, up to 40% of protein from the feedstuff pass to manuxe;
in cattle's manure there is presen-t a so-called "single-cell"
protein from ~icroorganisms of rumen containing aminoacids, i.e.
more valuable protein, than vegetable protein contained in ~the
feedstuff.
Consequently, a number of rnethods f'or processing manure
are directed to the provision OI' a protein component direct-
1~ from manure for the utilization thereof in an animal feed-
stuf'f~ As to the type of processes on which said methods of
manure treatment are based, they may 'be classified into
ermophysical, thermochemical and biochemical processes with
a single-stage or multi-stage biochemical filtration of harful
substances. ~he most popular process based on thermophysical
technology for recover~ of non-digested proteins from manure
is a so-called "Cereco"-process.
This process consists in the following: the manure
collected from a farm is diluted with water to the moisture
content of 80% and, after passing a number of separators, is
divided into three fractions. ~he fibrous fraction (product Cl -
non-digested vegetable remnants) is ensilaged and fed to feeder
bulls. The liquid fraction is e~aporated7 dried and granulated.
The resulting product (C2) contains up to 30% of proteins, 4%
of fats, 25% of ash; the product in the form of granules lS
employed for feeding pigs and poultry.
~ he ash residues and non-assimilated feedstuff components
recovered upon separation are employed as a fertilizer tproduct
C3). The process makes it possible to recover, within a short
period (up -to 6 ~ays), non-di,gested nutrient subs-tances from
manure on a commercial production scale at a high degree of the
product sterilization~ relatively low power consumption and
reauced degree of the environment pollution. However~ the thus-
obtained products have no-t been approved by national medical
control authorities of any country for their extensive
utiliza-tion as an animal feedstuff. This is due to the fact
that ha~mful substances (mycotoxins, heavy metals, pes-ticides
and the llke) in such treatment process are not fully withdrawn
from the feeding cycle and accumulated in the animal organism
As a result, after 3-4 recirculations this causes ca-ttle di-
seases (hepatocirrhosis) and, accordingly, affects quali-ty
characteris-tics of meat products.
~ urthermore, in the product C~ employed as a fertilizer
the organic mat-ter is absent almost completely, wherefore the
fertilizing capacity of` manure is substantially fully lost
for field-crop cultivation.
~ hermochemical processes for recovering feedstuffs from
manure may be exemplified by so-called t'Witingham process'l.
In this process, the manure collected from an open feeding
-- 11 --
'7~7
ground is dilu-ted with water to a 85% moisture content. Hav-
ing passed a~set-tling aerator, wherein heavy sedi~ents are
separated (sand ar1d the like) 7 the manure runoff is separated
in a centrifuge, the main portion of the nutrient substances
(especially Yat~ and proteins) still remains in the liquid
frac-tion which is then treated vrith ferric chloride to form
a ~ellow precipitate. 'rhe resulting precipitate is reco~ered,
dried and granulated to particles containing 30 to 50% of
crude protein. The solid fraction of the manure is l~ydrolyzed
by means of a~ alkali to give a product corresponding, as to
its energy pote~ial, to molasses.
'~he advc~ntages of this method, in addition to those of
thermophysical treatment methods, include the possibility of
~-ln accelerated incorpora-tion, into the feeding cycle o~
nimals, of addition~l mineral elements from manure (apart
from non-digested components).
The thermochemical "Witingham process" has not enjoyed
a wide application due to the same disadva~tages as those in-
herent in the thermophysical "Cereco-process".
The single-stage bioche~ical filtration of manure may be
exempli~ied by the "Bellami process" contempla-ting treat-
ment of manure for the production of a feedstuff comprising
a biomass of thermophylic bacteria on the manure substrate.
The process is based on an aerobic degradation of che-
mically treated manure cell-ulose t~sue and soluble nutrient
mat-ter by means of special bacteria capable of splitting cel-
- 12 -
lulose and lignin The process is effected in a series-connec-
ted fermenters, whereinto oxygen is fed to intensi~y the pro-
cess and a constant te~perature is maintained.
~ he resulting biomass slurry is collected, fil-tered and
dried to a consistence of a soft powder.
~ he product contains up to 55% of crude protein; the
process en_ahles utiliza-tion of up 9 % of the initial amount of
the manure e~ployedO
The use of processes of manure treatment by way of a single-
s-tage filtration of harmful substances makes it possible to
obtain a high yield of protein-containing products from manu-
re at a hi~h protein content.
However, the protein product obtained from the single-
stage -treatlnent of manure with bacteria incorporates al] the
harmful subs-ta~lces which have been present in -the star-ting
manure (myco-toxins, pesticides, heavy metals and the like).
In addition, the process of treatment using thermophilic
bacteria is rather power-consuming,
~ he fines-t biological ~iltration of harm~ul subs-tances
in processing of manure to a ~eedstuf~ is ensured by biologi-
cal processes such as traditional field-crop cultivation,
biological ponds, piscicultural ponds and the like.
Eowéver, hitherto known processes of biological puri~i
cation are substantially uncontrollableg necessitate large
areas (fields, ponds, basins), depend to a considerable ex-
tent on weather-climate conditions; they can be a source o~
- 13 -
pollution Df the envirDnments and ground waters. The dura-
t!ioa of the process required ~or obtaining Df the prDtein
prDduct is substantiallg increased (in field-crDp cultiva-
tion the yield is prnduced, as a rula, once a year; fish
breeding alsD lasts fDr several mDnths). Therei`ore, m~dern
prDcess Df multi-stage biDlogical filtration are least suitable
fDr the use thereof in the system of an intensive animal-
-breeding.
Apart from tb~ abDve-described methDds there have been
efforts tD prDduce a prDtein feedstuff Dn the basis Df products
from manure prDce~sing bD wa~ Df an aerobic puriLicatiDn nvt in-
tended specifically to the production of feedstuf~s from ma-
nure.
It is well known that durin~r aerDbic microbiDlogical
processing oY manure ~he nutrient substances there~f are cDn-
verted tD protein of single-cell bacteria and infusoria which
precipitate, after death, Dnto the bDtt~m Df aerotanks in the
fDrm Df a sD-called active DDze. It has been found in the
course of investigations that the cDntent Df protein in the
active ooze does not exceed 42%. The dry sDlids concentra-
tion in the active oDze dDes nDt exceed 6%. The prvcess ~f
treatment of the active DDze tD Dbtain prDtein feed additives
comprises cDncentratiDn Df the active DDze, its disintegra-
tiont tbermal sterilizatiDn and drying.
The use of this process fDr the prDduction Df proteins
frDm manure makes it possible to somewhat increase the pro-
- 14 -
fitability of such expensive purifica~ion systems as aero-
tankS. However, this process feature essential disadvc~ltages,
namely:
1. Since the content o~ dry solids in -the starting ac-
tive ooæe is at most 6~ot a complicated, power-consuming
equipTnent is necessary for its thickenin~.
2~ The process of ther'nal s-terilization can be carried
out at a very small e~posure (of the order of some decimal
l`ractions of a second) simu]ualeousl~ v~ith R hlgh concen-tra-
-tion of -tnerlnal energy (so-called ~Iheat shockl') 9 otherwise
ar.~inoacids ~ld single-cell proteins contained in the ac-tive
ooze are (3ecomposed alol~ wi-th k~lminth eg~s .~1d o-ther
patho~e:rls to be killed, whereby -the feeding capaci-ty OI -the
active ooze is decreased. ~he process equipment employed for
sucll operations is ra-tker e~pensive and unreliable in opera-
tion.
3. The protein product ob-tained by this process is IlOt
exempted of the harmful substances present in -the s-tarting
manure.
It is an object of the present invention to overcome
the above-mentioned disadvantages.
It is -the main object of the present invention to pro-
vide a process ~or an intensive treatment and utilization of
animal~breeding wastes which would ensure, along with the
production of organic fertilizers, also a feedstuff protein
complying with the modern requirements of medicine and zoo-
techny at the highest possible level of implication of the
nutrient substances contained in the wastes into the feeding
cycle of the agricultural production and at a full-fledged pro-
tection o~ the environments from pollution with animal-breeding
refusals both at the site of their processing and d~ing use
thereof in the plant growing.
I-t is another object of the preseMt invention to provide
a process ~or treatment o~ other organic wastes resulting
from agriculture and industry.
Still another object o~ -the present invention is to
provide a con-tinuous-action apparatus which would ensure an
intensive carrying-out of microbiolgical processes and a quick
separation o~ the fermented mass into the liquid and solid frac-
tions simultaneousl~ with the conversion of the latter ~raction
to a complex organo-mineral fertilizer.
~ hese and ~ther objects o~ the present inven-tion are ac-
complished b~ that in a process ~or utilization of the pro-
ducts of vital activity of animals comprising anaerobic fer-
menta-tion of manure under continuous stirring, separation o~
the fermented mass into the liquid and solid fractions empl-
oyed for fertilizing and separation of a biogas, in accord-
ance with the present invention, manure prior to the anaero-
bic ~ermentation is subjected to the treatment by decompression
and the anaerobic fermentation is conducted under the con-
- 16 -
ditions of controllable decompression and the resulting bio-
gas and other ni-tr~gen- and carbon-containing components
after -their evolution from air exhausts from the cattle hous-
es and from the liquid fraction o~ manure are employed as
trophic elements o~ the culture ~edium in the aerobic pro
cess~ wherein they are subJected to t~e ~reatmen-t with proto-
trophic bacteria; the biomass of the latter is disintegrated
and used as a feed component; the gas mixture effluent from
the treatmerlt \~ith prototrophic bacteria is used as a heat-
transfer agent in the system of the anaerobic fermentation,
while the fermented mass is precipitated by means o~ a m:lne-
ral-organic suspension prior to separation into fractions~
~ o improve disintegration and dispersing of mallure, as
well as to accelerate the beginning of the process of anaero-
bic fermentation of manure and subsequently intensify the
same, said decompression treatment of manure should be pre-
ferably e~fected by way of saturation thereof with a gas
under pressure of from 50 to 120 kg/cm2, followed by decomp-
ression (or pressure rlease) to 0 - ~-1,200 mm H20).
~ o prevent the manure mass subjected to the decompres-
sion treatment, from saturation with oxygen which is an inhibitor of
the anaerobic process, it is advisable to use biogas as a gas
for saturatio~ of the manure mass.
~ o accelerate withdrawal of gaseous products of metabo-
lism from the culture medium containing methane bacteria7 it
- 17 -
is advisable that the decompression in the fermentation cham
ber be maintained within the range of from 0 to (-1,200) mm
E20 along with cyclic agitationj each agitation c~cle being
started upon the achievement of the decompression of -100 ~o
(-900) mm H20.
~ o ensure the biosynthesis of protein, in the process
use may be made of methane-oxidizin$ microorganisms of the
following species, predominantly:
Methilococcus capsulatus;
Methilosinus trichosporium;
.
Me-thilosinus sporium.
~o intensify the process oI protein biosynthesis, it is
advisable ~hat the aerobic process be conducted under an over-
atrnospheric pressure of the gas mixture; the following process
conditions for cul-turing are preferred:
culture medium temperature 30 -to 45C;
acidity (pH) 5~5 to 7~o;
pressure of oxygen-containing gas. 101-40 kg/cm2
(abs);
content of carbon dioxide up to 30%.
To intensi-fy the process of separation of the fermellted
mass into the liquid and solid fractions, as well as to ba-
lance the composition of the resulting organic fertilizer as
to the principal fertilizing comp~nents (~itrogen9 phosphor-
us, calciu~), it is possible to use, as the precipitating
agent, a suspension of the following composition:
_ 18 -
t/~7
monoammonium phosphate (N~4H2P04) 5 -to 15~;
calcium chloride (CaCl~) 5 to 15%;
dilue~t (liquid fraction of manure~ the balance,
the volume ratio between the suspension ~nd the mass being
precipitated is varied within the range of from 1:1 to 2:2.
~ he object of the present invention is also accomplish-
:~d by that in an apparatus for utilization of the wastes
resulting from animal breeding and comprising an anaerobic
microbiological reactor having a fermentation and accumula-
tion vessels provided wi-th a heating system, as well as with
means for supplying ma~ure and withdrawing the fermented
mass, -the lat-ter means being communicated to the means for
separation of the fermented mass into -the liquid and solid
fractions 7 and the accumu].ation vessel has the means for
withdrawal and purification o~ the biogas, in accordance
with the present invention, the accumulation vessel is con-
nected, through ~eans for withdrawal of the biogas and puri-
fication unit, with an aerobic microbiological reactor pro-
vided with a biomass disintegrator, concentrator~ a piping
for the removal of the spent biogas to the heating system of
the fermentation vessel, while the anaerobic microbiological
reactor is equipped with means for automatic control and moni-
toring of intensity of the fermentation process.
It is advisable tha-t said means for automatic control
and monitoring of the fermentation process in-tensity be pro-
--19
vided with me~ns for maintaining a predetermined decompressi-
on (reduced pressure) inside the accumulation vessel and a
flow meter of the biogas quantity interconnected during the
adjustment of the pred.etermined fermentation in-tensity.
The means for ~aintaining a predetermined reduced pres--
sure should be preferabl~ made in the form of a bellow pump
consisting of a pressure chamber, bellows, generator of cyc-
les, pressure presetting means, pneumatic comparison eleT~ent
and pneumatic valves, two of which are comlected with -the
bellows, accumulation vessel and gas chamber, while the other
valves are connected wi-th the pressure chamber, pressure se-t-
ter and pneumatic comparison element one input of which is
cor.~ected to the bellows and the other - to the pressure set-
ter; the flow meter of the biogas aulount is connected wi-th
the cycle generator connected ~ith the pneumatic valves.
~ o increase reliability of operation and ensure a simple
structural arrangement at a required accurac~ of dispensing
of the manure supplied into the reactor, the means for supply-
ing -the manure and withdrawal of the ~ermented mass should
be preferabl~ made in the form of at least three non-commu-
nicating pneumatic chambers with ~uilt-in inlet, intermediate
and outlet insertions of a resilient ma-terial.connected with
socket pipes and be provided with a pneumatic pulse genera-
tor with its input directly connected to the chamber of the
outlet section, ~hile with the chambers of the inlet and in-
termediate sections it is connected through time delay elemen-tsO
_ 20 -
The present invention consists in the followings
On the ba~is of extensive studies and theoretical analy-
sis of regularities of processes of microbiological process-
ing of organic substrates it has been found that their in-
tensity d~pends on the accessibility of the substrate to a
microbiological degradation (homogenous character, absence
of competitive ~icroflora, low leve~ of a reduction-oxidation
potential), as well as on the conditions of supply of trophic
ele~ents into the culturi~g medium and with-drawal of
the metabolism products -therefrom.
It is known that in every cubic centimeter of manure
supplied for the treatment -there is about 6 bln of various
microorganisms among which, in addition to methane bac-teria
effectuating the process of anaerobic fermentation, there are
considerable amounts of microbes useless for the process
and competing with the working population for the common
substrate. ~or this reason, there takes place a susbstantial
delay in the normal process of methane fe~mentation of about
2-3 days as compared to the control (no competition).
~ 'he effect of the competing popula~ion on the process
pace is cl~aracterized by the following equation describing
the variation in quantity of the working population (y) with
time (t):
(l/y) (dy/dt) = r - ky - pz (1)
wherein r, k and p are positive constants corresponding to
specific conditions of growth of the population
habitant in a given medium;
- 21 -
z is the quantity of the competing population.
It follows from equa-tion (I) that elimination of the com-
petitive population ~z = O), all other factors being equal,
increases the pace o~ increasing the quantity of methane-
orming bacteria and, hence, the rate of the process of methane
:~ermen-tation.
It has been found in the course of experimen~al in-vesti-
ga-tiolls that the decompression treatment of the material en-
suring its sterilization prior to the supply into the cultur-
ing medium can reduce the process duration of methane-fermenta-
tion of manure by at least two da~s.
It has been also found that the rate of the process of
anaerobic decomposition o:f organic refusals can ~e restricted
not only by -the presence o~ competing populations of micro-
organisms, but by accumulation o~ the metabolism product i.
the culturing medium as well.
In this case such products are methane and carbon di-
oxide. It has been theoretically proven that the character
of the inhibiting effect of products of metabolism on -the
growth rate (M) of the working population is defined by the
expressi on
M = Mmax kp. S
(ks + S~ (kp~Pe) (2)
herein P is the concentration of the inhibiting metabolism
products in the medium;
kpis a constant characterizing the concentration o
metabolism products at M~p) = Mo/2
- 22 -
ks is a constant characterizing the substrate con-
cen-tration at ~(s) = Mo~2;
S is the concentration o~ the organic portion of the
substrate (manure or other wastes).
From this equation it follows that to increase the pro-
cess intensity, it is necessary (all other factors being
equal) to lower -the expression (~ + Pe) in the denominator
of the ri~ht part, i.e. to ensure a continuous withdrawal of
the metabolism produc-ts from the culturing medium.
It has been found by investigations that this can be
ensured by carrying-out the process under a reduced pressure
in the gas collector within the ran$e of ~rom 100 to 900 mm
H20 in combination with -the bulk agitation of the entire mass
being fermented.
Since the fermen~ed mass produced in the anaerobic ~ic-
robiological treatment of manure comprises a stable colloidal
solution ~`or a subsequent separation into the solid and li-
quid fractions~ it is advisable precipitate this massO
In the course of investigatior~ it has been found that
the most efficient for -this prupose is coagulation of the
fermented mass by means of electrolytes which do not stain
soil, are good precipitating agents and add to the fertilizing
capacity of manure. For electrolyte coagulation it is necessa-
ry that concentration of electrolytes be above a certain value
(coagulation treshould, mmol in g/l) defined by the expression:
- 23 -
~ = G ~2~kT)z5 (3
wherein C is proportionality coefficient;
D is dielectric cons-tant of the precipitated medium
(40 to 80 for -the fermented mass);
k ls Boltzmann constant;
e i~ electron charge;
T - te~perature, K
A Van der Vaals at-traction constant;
z - charge value of the dominating ion.
Therefore, pressure elevation in -the culturing system
is one of the me-thods for increasing the substrate concent-
ration (CH49 2) in the culture liquid. Since the process in~
tensity depends on the substrate (CH~ 2) concentration,
a higher pressure in the cul-turing system is one of the effi-
cient ways of increasing the process productivity.
In accordance with the present invention, the biogas
evolving in the anaerobic fermenta-tion of manure should be
utilized in the bacterial biomass in the aerobic process of
intensive fermentation.
~ ccording to Henry's law, Pa = ~ x, where y is Henry con-
stant, Pa - partial vapour tension above the liquid, x lS the
concentratio~ of a me-tha~e-containing gas in the liquid. ~he
concentra-tion of dry solids in the culturing medium and the
process productivity depend, substantially linearily, on the
pressure under which the culturing process is effected. In view
of this fact it has been experimentally shown that the aerobic
- 24 -
process of a microbiological oxidation of the biogas should bepreferably carried ou-t under a pressure of the gas phase in
the fermenter vJithin the range of fro~ 1~1 to 40 kg/cm~
(absol. atm.).
~ he above-mentioned principal relationships (1), (2) and
(3) have been chosen as the basis for the provision of a
process for treating the products of vital ac-tivity o~ animals
~o give organo-mineral fertilizers and a feedstuff protein,
as well as for designil~ large-capacity ~mits ~or anaerobic pro-
cessing of or~anic refusals on a commercial scale.
In accordance with the present invention, for precipi-
tation of a ~ermented mass use is made of` a suspension con-
SiStillg of 5 to 15% o-f monoammonium phosphate~ 5 to 15~ of
calcium chloride and a solven-t; as the latter use is made
of the liquid fraction of manure introduced illtO the preci-
pita-ted mass in the volume ratio thereto of 1:1 to 2:2.
The above-specified operations are combined by the pro-
cess for utilization of wastes resulting from animal breed-
i~g which is efficien-tly performed on the basis of controlled
microbiological processes occurring at a higher speed and
ensuring a hIgher efficiency of utilization of refusals o
the vital activity of animals as cornpared to the prior art
processes.
~ he process according to the present invention can be
performed only in an apparatus ensuring maintaining -the re-
- 25 -
quired process parameters. The coefficient of transformation
of the product~ of vital activity of animals to a feedstuff
actually attained in practice of the present invention ~this
coefficient means the ratio of the amount of nutrient sub-
stances and the products o~ their decomposition con-tained
in wastes resulting from the vital activity of ani~als to
-the amo~t of these substances transformed into a feedstu~f
complying with all zoo-sanitary requirements) is e~ual to
0.9 for plants with a working chamber volume of above 20 m3.
~ he experiments have shown that the use of the process
for utilization o-f-` the products resul-ting from the vital ac-
tivity of ani~als according to the present invention ensures
the produc-tion of concentrated org~lo-mineral fertilizers
without losses of nutrient substances. At the same time, a
higher level of involvement of nutrient subs-tances contained
in the products of the vital activity of animals is ensured
in the feeding cycle o~ the agricultural produc-tion.
The tr~lsformation of nutrien substances ~rom manure to
a feedstuff by mears of utilization thereof in ~ield-crop
cultivation proceeds but very slowly (within 2-3 years from
the moment of manure application onto soil~. The process accor-
ding to the present invention makes it possible to produce a
protein-rich feedstuff already a-fter 1-2 days since the sup-
ply of manure to processing.
From the products of the anaerobic treatment there can be
obtained more than 60 kg o-f proteins per every ton of absolu-
- 26 -
tely dry solids of manure. ~his means that from man~re ob-
tained from a feeding cat-tle enterprise per 10,000 capitae
-there can be produced about 600 tons of pro-tein annually (about
1,7 -ton o-f protein daily) without lowering the ou-~put of pro-
duc-tion of organic fertilizers and impairing their quality.
The experiments performea for feeding, to ~ni~alsg o~
a protein-vitamirl concentrate produced from the biomass ol
me-thane-oxidation bacteria pro~ed to cause no ~egative con-
sequences of a feed~s-tuff use of this product.
~ he effec-t obtained from -the use of the protein-vitarmin
concentrate of the microbial orgin as a feedstuff ~dditive
is similar to the effect ob-tained from the use, for the same
purpose, of conventional vitamin-protein ad~itives of the same
concentration.
~ 'he process according -to the present invention rn~es
it possible to accelerate, in an animal-breeding enterprise,
the cycle of bioconversion of feeding substances in parallel
to the traditional way of regeneration thereof in the field-
crop cultiva~tion, thus providing real opportunities for
maintaining animal-breeding enterprises as waste-free produc-
tio~ meeting all the requirements imposed by the environ-
ment protection control..
~ or a better understanding of the present inven-tion,
a further detailed description thereof is given ~Tith referen-
- 27 -
ce to the accompanying drawin~s sho~ing a process flow-sheet
and specific embodiments o~ certain indi~idual means, wherein
Fig.l is ~ schematlc ~lo~:-sheet of the process ~or uti-
lization of the products of the vi~al activi-ty of animals
according -to the present invention;
~ ig.2 is a diagra~ illustrating the arr~ngement of -the
appara-tus for dispensin~ ~anure;
~ 1~.3 is a schematic viev~ of the arrangement of the appa-
ratus ~or decompression treatment OI manure;
~ ig.4 is a schematic vie1.~ o~ the device for automatic
control and moni-tori.ng of lntensity of the manule ~ermen~a-
tion prGcess;
~ ig.5 is Q schematic vie~ of ~ ~oduclion line -for de-
hy-dra-tion o~ the fer1nel1ted m~nure mass;
Fig.6 illustrates in-tensit~ o~ precipita-tion of -the
fermented mass without treatmen~ (curves 1, 2 and 3) and with
the trea-tmen-t ol the fermented mass with a N, P, and Ca-con-
taining suspension (curves 1, 2 and 3).
'~he apparatus shown in the accompanying drawi~$ (~ig~2, 3,
5, 6 and 7) are incorporated in the plant (Fig l) ~or per-
i`orming the process according -to the present invention. '~his
plan~t incorporates an apparatus 1 for dispensing manure, a
disintegrator-homogenizer 2, an apparatus 3 ~or decompression
processing, an anaerobic microbiological reactor 4 comprising
- 28 -
a fermentation vessel 5 provided with a heating system 6, a
withdrawal 7 and recirculation means 8 for the fermented mass
and an accumula-tion vessel 9 provided ~ith means 10 for wlth-
drawal of the biogas and a devlce 11 for automatic con-trol
and monitoring of` the fermentation process intensity and a
purificatlon unit 12. 'rhe lat-ter is con~1ected with an aerobic
microbiologlcal reactor 13 ~Jith its inlet connec-ted, through
a concentrator-s-terilizer 14, with a ven-tilation sys-tem 15
of the cattle house 16 and provided ~ith a feeder 17 supplying
mineral components. 'rhe outlet of the aerobic microbiolo-
gical reactor 13 is connec-ted with a concen-tra-tor 24 of -the
biomass, while the latter is communicating with an appara-
tus for i-ts disintegra-tion 25. A pipe 2~ for the off-gases
effluen-t ~rom the aerobic microbilogical reactor 13 is con-
nected with the heating system 6 of -the anaerobic reactor 4
through a purification unit 27~ while a pipe 28 for the sup
ply of the oxidizing agent is connected with a source of an
oxygen-containing gas; as the latter gas use is made of air
from an air-blower 29 or oxygen from a cylinder 30.
'rhe appara-tus 1 for dispensing manure is schematicall~
shown in ~ig.2~
According to this ~igure, apparatus 1 consists of a tight
housing incorpora-ting sections of a resilien-t duct: inlet
section 31, intermediate section 32 and outlet section 33
made, for example, of a rubber pipe or hose. 'rhe air--tigh-t
- 29 -
housing is par-titioned, by means of mebranes 35 with socket
pipes, into three pneumatic chambers corresponding to -the
above-mentioned sections of the material duct.
These pneumatic chambers are connected through dela~
lines 34 and 35 consisting of rela~s formin$ a repetition
circuit and a cho~e 37 with a pulse generator 38. ~he variable
choke 37 ensures frequenc~ variation of the pulse sequence.
The apparatus 3 along ll~ith the anaerobic microbiological
reactor 4 iS schematically shown in Fig.3. It consists of an
inlet valve 39, a decompression cha~ber 40 provided with a
pressure indicator 41, an outlet valve 42 connected with an
injector 43.
A gas line 44 of the decompression chamber 40 iS connec-
ted, by means of valves 45 and 46, with a source 47 of comp-
ressed gas (at the moment of` start-up of -the apparatus) or
with means for compression of the gas 48 during normal opera-
tion~
~ he device 11 for auto~atic control and monitoring of
the intensity of the manure fermentation process is schematic-
ally shown in Fig~4 and comprises means 49 for maintaining a
predetermined reduced pressure in the accumulation vessel 9 by
means of a forced withdrawal of the biogas formed during fer-
mentation fro~ the accumulation vessel 9, said means having
form of a controlled bellows-type pump consisting of bello~s
509 pressure chamber 51, pressure se~ter 52, pneumovalves 53, 54,
55 and 56 and a pulse generator 57 ~ith a trigger 58; a con-
- 30 -
s~
trolled throt-tle valve 59, pneumatic vessel 60, pneumofvalve
61, comparison element 62 with one of its inputs connected
with a setter 63 of the extreme reduced pressure and the other -
-to the bellows 50 connected, through valve 55 with a gas
vessel 64, while the output is connected, through pneumovalve
56, to the pressure chamber 51; a meter 65 for recording qu-
antity of the withdrawn biogas consisting of a magne-t~controlled
contact 66, electropneumatic transducer 67 and a digital in-
dica-tor 68.
~ he apparatus for precipitation of the fermen-ted mass is
schematically shown in Fig.5~ It consists of a unit 69 for
preparation of the settling susper-sion with a con-troller 70
for feeding -the suspension, means 22 for recycling the liquid
fraction of manure, coagulator 71 provided with an impeller 72,
a se-ttling chamber 73, a separa-tor-granulator 74 and metering
means 21 and 23.
'rhe above-described plant and appara-tus inc~rporated
therein operate in -the following manner.
Manure from the cattle house 16 (Fig.l) is supplied by
means of apparatus 1 for dispensing (Figs 1-2) to disinteg-
rator-homogenizer 2, ~herein it is finely divided to partic-
les with a size not exceeding 1-2 mm and homogenized to a
uniform mass. After the disintegrator-homogeniæer the m~nure
is fed to apparatus 3 for the treatment by decompression re~
sulting in beaking of shells of the competing microorganisms
_ 31
5~
and helminth eggs. The biologically active substances evolv-
ing during this treatment into the manure mass accelerate the
process of metha~e fermen-tation in the fermentation vessel 5
of the anaerobic reactor 4, whereinto manure after the decomp-
ression -treatment is injected along v~ith an active leaven
containing the working association of methane bacteria. ~he
process is carried out at a tel~perature wi-thin the range of
from 50 to 56C, pH - 6.5 -to 7 a-t a reduced pressure in cha~-
ber 9 maintained within the range of from O to -1,200 mm H20.
Durir~ methane fermentation in the fermentation vessel 5
there occurs an intensive transforma-tion of -the organic pcr-
-tion of manure accompanied by conversion of vola-tile (mainly
ammoniacal) forrns of nitro~en to the stable (upon storage and
applica-tion) ammonium L orm and evolution of -the biogas con-
sisting of 65% CH4 (methane) and 35% C02 (carbon dioxide).
~ he fermented mass is withdrawn from the fermen-tation
vessel 5 by means of apparatus 7 for its withdrawal and deli-
vered to separator 18, whereinto the precipitating suspension
is also fed consisting of the liquid fraction 19 of manure
and coagulant~ i.e. mineral components having fertilizing
propelties, namely: 5 to 15% of monoammonium phosphate
~H4H2P04 and the same amount of calcium chloride CaCl20 ~he
precipita-ting suspenslon is mixed with the precipita-ted fer-
mented mass in the ratio therebe-tween of from 1~1 to 2:2.
Owing thereto, the precipitation rate is increased by doze~
- 32 -
iFP7
times as compared to natural sedimentation and, consequently,
power consumption for the recovery of the solid fraction 20
is reduced~
The biogas evolving during fermentation o~ manure is
removed from the accumulation vessel 9 by means of apparatus
10 for withdrawal of the biogas operated by means o~ a cont-
rol unit 11 i~corporated into the device for control and mo-
nitoring of the process OI methane fermentation. (~igs 1, 4).
~ hen the biogas passes through the purification unit
12 and further to the aerobic microbiological reactor 13,
whereinto wa-ter, sources of nitrogen~phosphorus, potassium,
magnesium and txace elements are fed by means of feeder 17
along with an oxygen-containing gas (air ~ and/or o~ygen from
cylinder 2~ or compressor 29, as well as nitrogen- and carbon-
containing gases adsorbed in apparatus 14 from the vent exhausts
from the cattle house 16.
As the strain producing protein substances use is made
o~ a mixed culture of microorganisms of the species:
Methilococcus capSulatus,
Methilosinus trichosporium,
Methilosinus sporium.
Op-tional methylotrophics incorporated in the mixed cul
ture of microorganisms and capable of assimilating methane
homologues pertain to the species Flavobacterium ~asotypicum.
~ he aerobic process of culturing is carried out at a
temperature within the range of from 36 to 50C; pH of the
- 3~ -
culture medium is kep-t within the range of from 4.0 to 6,0,
concentration of ammonia nitrogen - of ~rom 50 to 150 mg/l,
concentration of phosphorus - of from 50 to 100 mg~l.
~ he culturing process is carried out under an over-
atmospheric pressure of the gas within the range of from 1.1
to 40 kg/cm2. The recycled gas mixture is passed throuOh the
purification ~7nit 27, wherein it is e~empted from the excess-
ive a~oun-t of gaseous carbon dioxide, maintaining its con-tent
at a constant level. The continuous fermentation by means o~
the mixed culture is carried out a-t a dilution coe~ficient
of from 0~15 to 0.25 hr 1. The suspension o~ microorganisms
from the culturing stage in the aerobic reactor 13 is fed to
apparatus 24 for preliminar~ thickening, v~herein the strea;m
pressure is released, wherefore the gases dissolved in -the
cul-ture medium are desorbed from the liquid phase ~nd partly
from microorganism per seO Due to a high rate of pressure
release, shells of a certain portion o~ the cul-tured bacteria
get broken. As a resul-t, biologically active substances con-
tained inside the cells pass into the cult~lre medium; a por-
tion thereof, after said preliminary thickening in apparatus
24, is recycled to the aerobic reactor 13 and used for promo-
tion of the growth of microorganisms.
Carbon dioxide absorbed in the stage of purification
(in unit 27) evolved during biosynthesis and accompanying
componen-ts o~ the spent gas phase ~rom the cul-turin~ stage in
reactor 13, as well as the gas desorbed in thick~ener 24, are
- 34 -
~i1l5~7
mixed with atmospheric air and combusted in the heating system
of heat-exchange.r 6 through which heat-exchanger the fermen-
ted mass is passe~ by recirculating means 8 at i~tervals de-
pending on varia-tion of teMpera-ture iQ the fermentation vessel
5.
~ he resulting biomass of methane-oxidizing bacteria
thick_ened to a concen-tration of from 180 to 200 kg AC~/m3
is delivered to disintegra-tor 25, wherein bacteria shells are
broken, whereafter the thus-obtained concentrate is d.elivered
to feedstu.~ production shop 75, wherein it is admixed to
a feedstuff as a pro-tein additive, mainly in the liquid form.
'~he princi.ple of operation of the apparatus incorporated
in the plant scheme is illustrated by Figs 2,314 and 5.
Shown in ~ig.2 is the apparatus for dispensing manure.
It is employed both for the supply of manure into the fermenta-
tion vessel 5 and for withdrawal of the fermented mass there-
from, feeding the filtrate into the precipitation apparatus 18
and pumping the mass being fermented through heat-exchanger 6
~ he apparatus operates in the followqng manner.
~ he metered or dispensed medium (liquid manure, cul-ture
li~uid or filtrate) fills sectio~l3 31, 32 and 33 of the ma-
terial duct, whereafter under the effect of pnuma-tic pres-
sure form.ed at the ou-tlet of pulse generator 38 the final
section 33 of the material duct is compressed thus closing
the outlet of the me-tered medium
~ 35 -
P7
At the nex* moment the inlet section 31 of the material
duc-t is closed under the e~fect of pneumatic pressure at the
outlet o~ the delay line 35 and the entire volume of the
medium being -transfexred aild filling ~he resilient material
~uct becomes enclosed in the intermediate sec-tion 32. ~here-
a~terq the output of pulse generator 38 is zero, the ter-
minal section 33 ls opened, while the i~termediate section
32 controlled through line 36 is compressed, thus expelling
the medium enclosed therein towards the terminal section 33,
which af-terwards îs compressed under the effect of -the nex-t
pneumatic pulse as -the output o~ genera-tor 38, -thus with-
drawi.ng this particular por-tion of the medium ou-t of the appa-
ratus. Since, a~`terwards, pressure in pneuma-tic chambers of sec-
tions 31, 32 and 33 is again released, these sections become
opened and are prepared for the following cycle o~ filling
of -the resilien-t material duct with the medium to be metered
(or dispensed)
Prior to supply into the anaerobic microbiological reac-
tor 4, manure, accordin~ to the present invention, is sub-
jected to the treatment by decompression with the view to
enhance accessibility of this coarsely dispersed medium to
~icrobial degradation and suppress the accompanying micro-
flora inhibi~ing the gro~th o~ the working population of methane-
oxidizing bacteria.
According to the diagra.m shown in Fig.3, m~ure is ~ed
- 36 -
~L~ 7
through the inlet valve 39 i~to the decompression chamber 40;
biogas is delivered through line 44. The biogas is formed
during methane fermentation in vessel 5 and is pumped~ by
means of the high-pressure pump 48, through valve 45 to line
44, or through valve 46 to the accumulation receiver 47 re-
quired :Eor storage of the excessive biogas and for operation
of -the decompression chamber ~0 during the start-up of the
anaerobic reactor when no biogas is evolved yet~
When the biogas pressure in the decompression chamber
reaches 50 to 120 kg/cm2, valve 40 is closed, ou~let valve
42 is opened, whereby the gas-liquid mix~ure is injected
into -the fermentation vessel of the anaerobic reactor through
the injector 43.
Due to a sharp pressure drop, the microor~anisms,and
vegetable particles are broken at the moment of discharge
from the ~leco~pression chamber thus subs-tantially enhancing
the access'ibility of the s-tarting substrate (manure) ~or the
treatment by microorganisms of the working population.
Control and monitoring of the anaerobic fermentation
process is ef~ected by means of device 11 schematically shown
in ~ig.4. ~his device ensures automatis adjustment of such a
reduced pressure in the anaerobic reactor under which the pro-
cess intensity is maximal. ~he amount of biogas evol~ing per
unit time corresponds to the process intensity.
The device operates in the following manner. The ferment-
ed mass is discontinuously fed to the fermentation vessel 5,
~ 37 -
wherein condi~io~s required for the normal vital activity ofmethane bacteria are provided. As ~he biogas produced by these
bacteria evolves from the mass being fermented, -this gas passes~
through pneumovalve 54, to the variable-volume pneumatic
vessel 50 con~ected wi-th a controlled actuator. ~wing thereto,
simultaneously with intermixing of the fermented mass there
occurs an intensive re~oval of the gaseous products of meta-
bolism of methane bacteria in -the form of a methane-containing
gas at a pressure drop in the fermentation vessel from 0 to
(-1,20~) mm H20. 'rhis results in a substantially increased
intensity of the fermenta-tion process. Vacuum over the fermented
mass is preset by means of a vacuum setter 63 connected with
one of -the chambers of the comparison element 62. In this
manner a proportional flo~ rate of air frQm the pressure cha-
mber 51 of apparatus 8 (Fi~.l) is ensured for a forced removal
o~ the formed biogas from the fermentation vessel 5 under
vacuum, at a given value of vacuum in bellows 50 depending on
the supply oY the biogas.
When bellows 50 occupy their upper most position thus
hinderin~ its full filling with the biogas, contacts of -the
magnet-controlled sensor 66 are actuated, the supply circuit
oY the electropneumotransducer 67 and digital indicator 68 is
energized. At the same time, air pressure is admitted into
trigger 58 oY the tact generator 57. ~ith air pressure incre-
ased -to the value of pressure ol the highest headt the trigger
(flip-flop) 58 is switched over. Simultaneously pneumovalves 53,
- 38 -
54~ 55~ 56 and 61 are also switched. A~ i pressure necessary
for deformation o~ bellows 50 is admit-ted -to the pressure
chamber 51 -throu~h the pressure set-ter 520 The blogas from
bellows 50 -through pneumovalve 55 ls e~Ypelled to -the gas vessel
64. At this moment pneu~ovalve 56 prevents from the admission
of excessive pressure to th~ comparison member 16, while
pnellmovalve 54 excludes backward feed of the bio~as into the
accumùlation vessel 9. ~hen the bello~i~rs 50 come ~rom -their
uppermost position to the lowermost one, -the contacts of the
magne-t-controlled transmitter 67 are opened; the elect,ropneumo-
tra,lsducer 67 is swqtched to -the ini-tial pOSitiOIl and at i~s
outpu-t the "zero" signal is produced.
The f`lip-flop 58 is s~itched to the normal position af-
ter the time ;nterval equal to the time required I`or filling
pneumo,vessel 60 and emptying bello~Js 50, -thus connecting
the control chambers OL pneumovalves 53, 54, 55, 56 and 61
to the atmosphere. In the pressure chamber 51 the preset
pressure is memorized, the accumulation vessel 9 is connect-
ed with bellows 50, the pressure chamber 51 - ~ith the com
parison element 62, and pheumovessel 60 - with -the atmosphere.
The line connecting bellow 50 with the gas vessel ~4 is dis-
connected. ~hen the cycle is repeated.
The time of full emptying of bellows 50 is set by means
of a controlled throttle val~e 59.
This device makes it possible to intensify the process
of-anaerobic treatment of manure due to an intensive removal
- 39 ~
of the product of bac-terial metabolism in the form of biogas
bubbles evolving from the fe~mented liquid at a pressure
drop over it from 0 to (-1,200) mm H20.
Furthermore, the device enables a strict automatic
control of the fermentation process intensit~.
After anaerobic treatment of manure a fermented mass
is obtained in the 1orm OI a colloidal solution. ~Q ensure
its efficien-t dehydration, it is necessary to precipitate
or~anic colloids, wherefor the use of conventional methods
of precipita-tion using metal-containing coagulants is unde-
sirable due to their high cost and danger of contamination
o~ soil a~d ground water with harTnf`ul compounds.
In this connection, instead of a metal-containing co-
agulant in the process according to the resen-t invention
use is made o~ a precipitating suspension consisti~ of mi-
neral fertilizers - monoammorlium phosphate ~H4H2P04) - 10
and calcium chloride (CaC12) or lime - l~/o~ As the liquid
phase of the dispersing medium use is made o~ the liquid
fraction of ma~ure obtained therefrom during separa-tion. ~he
precipitating solution in the volume ratio of 1 1 or 2:2
is introduced into manure having temperature v/ithin the ra~ge
of from 50 to 55C (-the manure temperature a-t the outle-t
of the methane tank) and intensively stirred, ~hereafter it
is subjected to settling for 10-15 minutes; during this time
the mix-ture is rapidly separated into fractions in the ratio
o~
-- 40 --
y~
~ he liquid fraction is drained and the residue is ~ed
to mechanical separation.
Af-ter treatment of manure b~ the process according to
the present invention, the ~r`il-tration time is reauced `oy 10
times and more; as a result9 a complex organomineral fer-ti-
lizer is produced which is balanced in respect of the con-
tent of N, O and Ca. An example of the process according to
the present invention is illustrated by the flo~r-sheet of
one of its embodiments as shown in.~ig.5. According to thi.s
flow~sheet, a fermented manure mass at the -temperature of
55C ~rom the fermentation vessel 5 is delivered to the coa-
gula-tion chamber 71 provided v~ith stirrer 72; into said cham-
ber a preliminarily prepared precipitating suspension i~ fed
through the charging rneans 70 in the ra-tio of 1:1 -to 2:2
(two parts by volume of the solution per two parts by vo]ume
o~ manure) and intensively mixed with manure. The thus-pre-
pared liquid manure is charged into the sedimentation cham-
ber 73, wherein it is intensively strati~ied to the liquid
fraction and -the residue; the latter is ~ed to means 74 for
dehydration an~ granulation, ~1ile a portion of the liquid
fraction is passed, through line 22, -to chamber 69 for the
preparation of the liquid pre.cipitating suspension, whereinto
monoammonium phosphate (~H4~2P04) is fed through the metering
device 21 ln an amount of from 5 -to 15~ and calcium chlorlde
CaC12 or lime in an amount of from 5 to 15%.
- 41 -
During the start-up period, until the liquid mamlre fil-
trate is ob-tained, as the dispersing medium use is made of
conventional process water~
'rhe process accQrding to the present inven~ion, due to
a reduced -time required for separation of manure to fractions
7~akes i-t possible to increase, by more th~ 10 -times, the
productivity o~ separating apparatus. Furthermore, in the
liquid fraction of manure there are substa~tially no suspen-
ded l~articles. In ~ig.6 curves 1, 2, 3 and 4 illustrate na-tu-
ral precipitation of liquid manure: 1 - fresh manure; 2 -
fer~nelted manure; 3 - fresh manure in combina-tion with the
prGcipitating solution; 4 - fermented manure in comb.ination
with -the precipitating solution.
~ o plot the curves, into measurin~ cylinders there are
poured 60 ml of the test mallure and the vol.ume of -the preci-
pitate is recorded after specified time periods (as percen-
tage of the total volume). From the obtained relationships
it is clear tha-t it takes about 50 hours to obtain 20% of
precipitate in fresh manure, whereas ~ermented manure is
substantially not stratifiedO A~ter mixing o fresh or fer-
mented manure.with the precipitating solution 50% of preci-
pitate are formed within 10-12 minu-tes, whereaf-ter volume
increase is stopped, i.e. the rate of natural precipitation
is increased by about 300 times; the liquid phase has a yel-
lowish colour and contains no suspended particles, ~Ihereas
in fresh manure the liquid phase has a dark colour an~ in
- 42 -
its upper part a crust is present con~isting of suspendedparticles. Curves 1, 2, 3 and 4 illustrate relationships
of the rate of filtra-tion of the same volume ~50 ml) of the
test manure, all conditions being equal (temperature, reduced
pressure, ~iltra-tion area, filtering paper); these curve~
demonstra-te that ferinen-ted manure is not filtered substantial-
ly, while fresh manure is filtered by 60% within 14 minutes
and the filtration is the~ stopped. Filtration of the total
volume (60 ml) of the same kinds of manure ~ixed with the
precipitating solution takes 50-60 seconds, i.e. the rate of
filtration is increased proportionally to the rate of na-tu~
ral precipitation.
The filtrate of liquid manure produced from the feImen-t-
ed mass ncessitates no desinfec~ion, thus making it posslble
to apply it by means of sprinklin~ uni-ts or units for sub-
soil application.
'~he solid fraction of manure produced in -this case in
the form of ecapsulated granules with a shell of mineral compo-
nents comprises a compleæ organo-mineral fertilizer which
can be in~troduced into soil by e~isting sprayers or mineral
~ertilizers or locally for plaLlt nutrition The necessity of
providing special ~achines for scattering organic fertilizers
is thus avoided. ~he economic effect from t~e use of this process
is obtained mainl-~- due to a considerabl-g increased crop yield,
higher productivity of separa~ing apparatus (resulting in
considerable savings in expenditures for processing of one ton
of manure) and due to a reduced number of` machines required for
scattering of organic fertilizers.
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