Production of feed from potato pulp loss 1. Method of preserving potato pulp. Use of potato solubles

Potatoes are not only a valuable food crop and feed product used in livestock farming, but also one of the most common types of raw materials for a number of industries Food Industry, in particular alcohol and starch paste. Nitrogen-free extractives are represented in potatoes by starch, sugars and some amount of ientosan. Depending on the storage conditions of potatoes, the sugar content in them changes noticeably. in some cases may exceed 5%. Potato nitrogenous substances consist mainly of soluble proteins and amino acids, which account for up to 80% total number protein substances. According to the conditions of starch production technology, soluble substances are usually lost with wash waters. The production waste at potato starch factories is pulp, which after partial dehydration (humidity 86-87%) is used as livestock feed.

The starch content in the pulp depends on the degree of potato grinding. According to M.E. Burman, in large, well-equipped plants, the coefficient of starch extraction from potatoes is 80-83%, and in low-capacity plants it is 75%. Its increase is associated with a significant increase in the energy capacity of the enterprise, and, consequently, capital costs. Currently, at some leading enterprises of the starch and syrup industry it reaches 86% and higher. Pulp used as feed is a low-value and perishable product. 1 kg of pulp contains 0.13 feed units, while fresh potatoes contain 0.23. Feeding fresh pulp to livestock should be limited. When processing potatoes in specialized starch factories, 80-100% of the pulp by weight of the potato is obtained, and a significant part of it often remains unsold.

Use of potato solubles

Many years of experience in the starch industry have shown that the problem of using potato solubles is one of the most difficult. It is still not permitted either at domestic starch factories or at foreign enterprises. Even in pre-revolutionary Russia, with the goal of more effective use Potato pulp began to be processed at distilleries located near starch factories. However, according to G. Fota, such processing turned out to be unprofitable due to the low alcohol content in the mash. Some distilleries in Czechoslovakia used combined processing of potatoes into starch and alcohol, in which they used not only potato pulp, but also part of the concentrated washing water.

This technique not only increased the utilization rate of starch, but also made it possible to partially use the soluble substances of potatoes. Below is a diagram of the balance of potato dry matter during the combined production of starch and alcohol at a pilot plant in Norway. In the USSR, M.E. Burman and E.I. Yurchenko proposed combining starch and alcohol production on a fundamentally new basis. It is recommended to extract only 50-60% of starch from potatoes, which makes it possible to transfer more than rich in starch pulp, as well as simplify the process of starch extraction, eliminating the operations of repeated washing of the pulp and secondary grinding.

With this method of potato processing, production efficiency is ensured by the following factors: almost complete use of the starch contained in potatoes for the production of main products (starch and alcohol); receiving stillage instead of low-value pulp -. very valuable nutritious feed for livestock; the use of most of the soluble substances of potatoes in the alcohol workshop or for microbiological production organized at distilleries; reduction of transport and general plant costs; savings on capital investments in the construction of a starch shop according to a simplified scheme at an existing plant.

The method of combining the production of starch and alcohol based on a distillery has found wide application in industry. By 1963, more than 60 potato starch shops were put into operation at distilleries. Technological diagrams starch production is based on the above-mentioned principle, however, in the hardware design they are somewhat different from each other. Below is a diagram proposed by M.E. Burman and E.I. Yurchenko for the Berezinsky plant. It provides for the use in alcohol production of not only potato pulp, but also soluble potato substances. The latter are released in the form of cell sap on a shaking sieve when the potato porridge is slightly diluted with water.

To separate the starch, the cell juice is sent to a sedimentation centrifuge, after which it is sent to a collection of products transferred to the alcohol workshop. The pulp is washed on a two-tier extractor or shaking sieve and sent to a pulp press, then enters the collection. Mud starch from traps is also supplied to the distillery for processing. Starch milk is purified from soluble substances in a sedimentary centrifuge, and from fine pulp - in refining sieves.

Its final cleaning takes place on the gutters. The separation of potato soluble substances is provided before the starch is washed out from the porridge, in order to obtain potato cell sap in a slightly diluted form and not to reduce the concentration of dry substances in the mixture of products entering the distillery. However, as factory experiments have shown, a shaking sieve is an unsuitable apparatus for isolating concentrated cell sap. According to the author's research, on a sieve with an area of ​​2.5 m2 with twill mesh No. 43, with a potato productivity of 1.0 thousand per 1 m2 of sieve and a vibration frequency of 1000-1200 per minute, cell juice from undiluted porridge is released in small quantities. In table Table 1 shows data characterizing the release of cell sap when potato porridge is diluted with water.

Abstract of the dissertation on the topic "Technology and dehydrator of potato pulp for livestock feed"

RYAZAN AGRICULTURAL IZHGUT NAMED AFTER PROFESSOR P.A KOSTSHEV

As a manuscript

ULYANOV Vyacheslav Mikhailovich

Uda 631.363,285:636.007.22 -

TECHNOLOGY AND POTATO PRODUCER GOES TO ROOT CATTLE

Specialty 05.20.01 - mechanization of agricultural production

dissertation for the degree of candidate of technical sciences

Ryazan - 1990

The work was carried out at the Department of Mechanization of Livestock Husbandry of the Ryazan Agricultural Institute named after Professor P.A. Kostycheva,

Scientific supervisors: Doctor of Technical Sciences, Professor V.F. Nekrashavich, Candidate of Technical Sciences, Associate Professor M.V. Oreshkina,

Official opponents - Doctor of Technical Sciences, Professor Terpilovsky K.F., Candidate of Technical Sciences Mestyukov B.I.

The leading enterprise is the All-Russian Research and Design and Technological Institute of Livestock Mechanization (SHIIMZH), Podolsk.

The defense will take place on “II” October 1990 at a meeting of the regional specialized Council K.120.09.01 of the Ryazan Agricultural Institute at the address: 390044, Ryazan* st. Kostycheva, d. I.

The dissertation can be found in the library of the Ryazan Agricultural Institute.

Scientific secretary of the regional specialized council, candidate of technical sciences, associate professor

I.E. Liberov

:department ertats&z

GENERAL DESCRIPTION OF WORK

1.1. Relevance of the topic. In "Main directions of economic and social development USSR as of 1986.-. .1990 and for the period 10 2000" provides for a significant increase in livestock production. Of major importance for solving these problems is the expanded strengthening of the feed base through the use of by-products (waste) of the food and processing industry, including potato and starch production

In the country, up to 1.5 million tons of potatoes are processed annually into starch, while $40 of potato dry matter goes into production by-products - pulp and potato juice. Potato pulp and juice, containing starch, protein, fiber, fats and other substances, represent the most valuable raw material resource for meeting the feed needs of livestock farming. However, at present, waste from potato starch production is not completely sold for feed purposes, so in the country the loss of potato pulp amounts to more than $15, and loss of juice - $80. This situation with the use of by-products of starch production is mainly due to their high humidity (94...96$) and a very large volume of formation. The lack of special equipment for concentrating waste leads to the fact that starch factories are forced to dump part of the pulp and carton juice into wastewater. Wastewater, which has high biological activity, enters water bodies and pollutes the water, which causes environmental damage to the environment.

The most promising technologies for processing production waste into livestock feed are the use of mechanical dehydration, which ensures the concentration of potato pulp and solves the problem of producing food protein contained in juice.

However, the practical implementation of mechanical dehydration of potato pulp and technology for preparing feed from waste from potato-starch production is hampered due to the lack of necessary equipment for their implementation. Therefore, theoretical and experimental research aimed at modernizing the technology of preparing feed from by-products of potato-starch production and developing a reliable waterproofing system: kzr?e£elye0l pulp yael.t?)? .channnnx tasks

1.2. Purpose and objectives of the research. The goal of the work is to improve the technology for preparing feed from by-products of potato starch production and to develop a potato pulp dehydrator with justification of parameters and operating modes. To achieve this goal, the following research tasks were set: 1 - to develop technology and a design and technological scheme for a potato pulp dehydrator; 2 - study the physical and mechanical properties. potato pulp; ,3 - justify the criterion for assessing the working process of dehydrators of dispersed moisture-containing materials; 4 - develop mathematical model squeezed liquid from the pulp in a screw press; 5 - justify the parameters and operating modes of the dehydrator; 6 - test the dehydrator under production conditions and evaluate the economic efficiency of its use.

1.3. Objects of the study."The objects of the study were: potato pulp with different juice contents, a laboratory model of a double-sided compression screw press," technology and a pilot production sample of a potato pulp de-hairing machine.

1.4. Research methodology. Theoretical and experimental studies were used in the work. Theoretical research consisted of a mathematical description of the physical essence of the process of squeezing potato pulp in a screw press and analysis of the resulting equations.

When conducting experiments, standard and private methods, instruments and installations were used. Friction coefficients and the influence of basic parameters on the dehydration process were determined using specially designed instruments and installations. In this case, the forces were measured by strain gauges. Laboratory studies of the process of extracting juice from potato pulp in a double-sided compression screw press were carried out using mathematical method planning experiments. Processing of experimental data was carried out using methods of mathematical statistics,

1.5. Scientific novelty. The use of mechanical dehydration to concentrate potato pulp is justified. The physical and mechanical properties of potato pulp were determined. A scheme for the technical process of preparing feed from by-products of starch production and the design of a pulp dehydrator have been proposed (positive decisions of the BNSYALE on applications for inventions K- 4297260/27-30, * 4605033/27-33, "5 4537442/31- 26 and

a.s. L 1512666). ¡"[compiled equation that describes the process of dehydration of cargo Whole?s meegle in gnzhevs1" press: double-sided compressed,

theoretically substantiated its main design parameters and ■ identified optimal technological operating modes.

1.6. Implementation of work. Based on the research results, a pilot production sample of the pulp dehydrator was manufactured. Tests carried out in the production conditions of the Ibrad starch and syrup plant Ryazan region demonstrated its performance. The developed decompressor is recommended for installation in the potato pulp recycling line at starch factories. The research results can be used by design and engineering organizations. tions in the development and modernization of machines for dehydrating potato pulp and other materials with high moisture content. The technical documentation for the developed decontaminator was transferred to the Ryazan experimental plant TOSSSH.

1.7. Approbation. The results were reported and approved at scientific conferences Ryazan Agricultural Institute (1987...1990), Bryansk Agricultural Institute (1988), Leningrad Order of the Red Banner of Labor Agricultural Institute (1989), at the All-Union Scientific and Practical Conference "The Contribution of Young Scientists and Specialists to the Intensification of Agricultural Production "(Alma-Ata, 1989), at the All-Union Scientific and Technical Conference" Contemporary issues agricultural mechanics" (Melitopol, 1989), at the scientific and technical council of NGOs on starch products (Korea, 1989).

1.8. Publication. The main content of the dissertation was published in 5 scientific articles, two descriptions of inventions (a.s. I5I2666 ti I4I99I4) and three applications for inventions (positive decisions of the Vnzhgae on applications 4297280/31-26, 4605033/27-30, 4657442/31-26).

1.9. Workload. The dissertation consists of an introduction, 5 sections, conclusions and recommendations for production, a list of references of 105 titles and 5 appendices. The work is presented on 221 pages, including 135 pages of main text, 35 drawings and

II tables.

The introduction contains a brief rationale for the relevance of the topic.

2.1, In the first section " Modern methods and means for preparing feed from potato starch by-products. bodstee" based on published works, the main sections are presented

information about the composition and types of by-products of potato-starch production, issues of the effectiveness of their use in animal husbandry are considered. Marked various ways preparation of feed from potato starch production waste. The basis of all technologies is the mechanical dehydration of potato pulp. Technologies using mechanical dehydration make it possible to concentrate potato pulp and work to solve the problem of food protein contained in juice.

The analysis of patent and scientific and technical literature showed that despite the wide variety of dehydrator press designs, there is no reliable equipment for dehydrating potato pulp. Effective work dehydrators largely depends on the right choice their main parameters based on the study of physical and mechanical properties and the dehydration process of the processed material. Significant experience in theoretical and experimental research on the mechanical release of liquid from dispersed materials has been accumulated in soil mechanics, wet fractionation of green plants, chemical, food and other industries. These issues are discussed in the works of H.H. Gersevanova, V.A. Florina, K.F. Terpilovsky, V.I. Fomina, I.I. Iodo, V.A., Nuzhikova, N.I., Gelperina, T.A. Malinovskaya, A.Ya. Sokolova, A.A. Gelgera, A.B. Ivanenko and a number of other researchers. An analysis of theories on the dehydration of dispersed materials showed that the process of dehydration of potato pulp has been extremely insufficiently studied.

The process of potato pulp dehydration can be described on the basis of various theoretical approaches. If we consider the process of dehydration of potato pulp as two combined stages, the first is the thickening of the original pulp to 85...90%, and the second is the mechanical pressing of the condensed mass, then in principle, in its essence, the first stage corresponds to the laws of filtration, and the second - the laws of filtration consolidation .

In accordance with the stated purpose of the work and based on the results of the review and analysis of the literature, research objectives are formulated at the end of the section.

2.2. The second section, “Physical and mechanical properties of potato pulp,” outlines the program, methodology and results of research into the physical and mechanical properties of potato pulp. The study of these properties is necessary for the development of technology and equipment for dehydration of potato pulp. Therefore, the task of the research was to determine the numerical indicators of the main properties at high

viyas corresponding to dehydration regimes.

In accordance with the task, the following were determined: the density of solid particles of potato pulp, the change in friction coefficients, lateral pressure and filtration-compression characteristics from the squeezing pressure. The density of solid particles of potato megts lies in the range of 1026...1040 kg/m3. It has been established that the numerical values ​​of the coefficients of friction of potato pulp on a smooth steel surface decrease from 0.135 to 0.10, and on a perforated brass surface - from 0.37 to 0.24 with increasing spin pressure from 0.35 to 2.0 MPa. The coefficient of internal friction of the pulp decreases from 0.66 to 0.24 with an increase in squeezing pressure from 0.40 to 2.83 MPa, and the coefficient of lateral pressure decreases from 0.9 to 0.68.

It has been established that the process of filtration of juice from squeezed pulp is significantly influenced by filtration and compression characteristics. When the spin pressure increases from 0.20 to 2.60 MPa, the filtration coefficient decreases from 60 "НГ9 to 0.73 * 10 ~ 9 m/s, the compressibility coefficient - from 5.13 * 10"® to O^bTO "6 and the modulus of press-suosity - from 1.56 to 0.17. The porosity coefficient of the brain when the humidity decreases from 90 to 52.36% decreases from 9.0 to 1.1.

2.3. In the third section, “Theoretical prerequisites for substantiating the parameters of a double-sided compression screw pulp press,” the existing criteria for assessing the working process of dispersed materials dehydrators are considered, the design of a potato pulp dehydrator is proposed, the process of squeezing the pulp in a double-sided compression pulp press is theoretically studied, and a generalized model is obtained that describes the dehydration process . Analytical expressions are proposed to determine the basic geometric parameters of a double-sided compression screw press.

The proposed criterion for assessing the dehydrator’s work process is:

Pv (\Usr-\ChT)- (SO O- W/i)-(40Q-Wg) ■ Wu, j

Co ~ fWp- Wil) ■ (Wu - Wr)*- ü- JOO > ^ 1 >

where £a is the generalized criterion, kW"h"?! /T;

Py - power consumption, kW;

Wu, W

This criterion characterizes the specific energy consumption per unit reduction in moisture content of the pressed product. Yari po-

The power of the generalized criterion revealed that promising designs are presses with screw working bodies, working in conjunction with devices that provide filtering of liquid during the movement of the suspension.

The proposed potato pulp dehydrator (Fig. I) consists of two interconnected devices - a thickener I and a double-compression screw press 2. The pulp thickener contains a vertical cylindrical-conical body 3 with a tangential pipe 4 for supplying the suspension, a pipe 5 for the filtrate outlet and a pipe b for the removal of the thickened sediment . On pipe 5, the surface of which is perforated, an inertial cleaner 7 is installed coaxially. The inertial cleaner is a paddle wheel with scrapers located along the perforated pipe and rotating together with the paddle wheel around the pipe. The screw press consists of a frame 8, a perforated cylinder 3, at the ends of which there are necks 10 for receiving material from the thickener. Inside the perforated cylinder there is a screw II with a variable shaft diameter, increasing towards the middle. The screw is made of two symmetrical parts with opposite directions of spirals and a constant pitch. In the middle of the perforated cylinder there is a window 12 for the exit of the boiled pulp and a device for regulating the degree of dehydration, made of two conical disks 13 located on both sides of the window and capable of symmetrical movement along the perforated cylinder. Filtrate collectors 14 are installed under the cylinder.

The design features of the dehydrator include the following. Pulp thickeners are installed above the source material bins. The neck press at opposite ends of the perforated cylinder has loading necks for the product, and in the middle there is a double-sided compression section. The screw is made symmetrical relative to the middle with an opposite spiral and a gap in the area of ​​the outlet window for removing the pressed product. This design of the press allows the material to be compacted on both sides with uniformly distributed pressure, thereby increasing the degree of dewatering of the pulp and increasing productivity theoretically by two times compared to single-sided pressing presses. The radial output of the pressed product contributes to the stable: *: holding of the “plug” of devolved material in the area of ​​the exit window, which stabilizes the working process of the press, - In the snack: press with sserle forces smm"/etrich -

Design and technological diagram of a potato pulp dewatering machine: I - thickeners; 2-screw press, double-sided compression; 3- cylindrical-conical body; 4- tangential pipe; o - pipe for drainage of iltrate; 6 - outlet pipe for condensed sludge; 7- shtrtsnonshl cleaner; 8- bed; 9- perforated cylinder; 10- receiving necks; II- auger; 12-output, window; 13- conical helmets; 14 - filtrate collections.

Their sides of the screw are directed towards each other and theoretically cancel each other, and this makes it possible to abandon special thrust bearings.

Due to the greater knowledge of thickening devices and the limited scope of the dissertation, the task of the research was to theoretically and experimentally substantiate a double-sided compression screw press.

The process of dehydrating potato gas in a double-sided compression screw press has two characteristic zones. From the loading necks of the press to the end of the last turns of the screw is the spin zone, from the end of the last turns to the discharge window is the compaction zone. By studying the process of pulp dehydration in the squeezing zone of a screw press, a general formula was obtained. A quantitative equation described this process. It looks like this:

Rice. 2. Design diagram of a double-sided compression screw press.

Humidity of the squeezed pulp; £ - spin time;

2 - coordinate directed along the axis of the screw; "O. - theoretical coefficient. The theoretical coefficient A. is determined from the expression:

where szb is the taper angle of the auger shaft, degrees; /Sdz - filtration coefficient, m/s; /ts - compressibility coefficient, m?/N; ^ - total mass of potato juice, kg/m3; ^ - free fall acceleration, m/s.

Coefficient a. reflects the relationship of both design parameters and physical and mechanical properties of the pressed pulp.

In order for the solution of equation (2) to be completely definite, the function ¿) must satisfy the boundary conditions corresponding to the physical conditions of the problem. For the process of squeezing liquid from potato pulp in the device being developed (Fig. 2), we select the following initial and boundary conditions:

(9th law of change in moisture content of squeezed pulp along the length

shock press; U/0 - initial moisture content of potato pulp.

The solution to equation (2) is found by the method of separation of variables.

De. Yk is the coefficient of the Fourier series; k - 1,2,3,

The length of the press spin zone, and; e is the base of the natural logarithm; £ - spin time, s."

The stability of the proposed press depends on the formation and holding of a “plug” from the pressed material in the area of ​​the outlet window. The stability of the “plug” primarily depends on the length of the compaction zone located between the ends of the last turns of the screw.

Since the ice press of double-sided compression is symmetrical relative to the H-H axis, we consider that in this section there is a conditional partition, to the right and left of which the same pressure is applied. This allows us to consider both parts of the press separately (Fig. 3). To determine the optimal length of the compaction zone, consider the equilibrium of the elementary layer s/g. at a distance of 2 from the H-H axis. Under the influence of force factors arising during the compaction process; axial pressures Pr and (Pas^P^), lateral pressures, the equilibrium equation will have the form:

Rg-R-rg + MgUR+uh-r + (8)

where P is the cross-sectional area of ​​the selected layer; tR;

Friction coefficients on the inner surface of the perforated cylinder and the screw shaft; T), c1 - respectively, the diameter of the perforated cylinder and the monk shaft, m.

After appropriate substitutions, transformations and solving the differential equation (8), we obtain φ<тулу для определения длины

seal zone: / p „ , "

/ (/g T) + -¿gsr, about 5

Rice. 3. Schemes for calculating the length of the sealing zone (a) and the width of the outlet window (b) of a double-sided compression w-pulley press: I - perforated cylinder; 2- auger; 3- exit window.

where, P is the pressure in the cross section of the last turn of the auger, N/m2;

Ra is the pressure in the suction at a distance of /2 from the H-H.N/m2 axis; - lateral pressure coefficient; th-, - width of the outlet window, m. Due to the fact that the pressed product is removed from the press in the diametrical direction, then in the area of ​​the outlet window where the axial movement of the pulp changes to radial, the layers of pulp move relative to each other, which must be taken into account by input coefficient of internal friction /th. Therefore, let’s draw up a differential equation for the equilibrium of a selected element of material with thickness с|_р at a distance £ from the axis of the screw shaft at the moment of its shift in the direction of the outlet window (Fig. 36):

0 (10) where is the cross-sectional area of ​​the elementary layer, m^;

£ - pershetr of the transverse layer of pulp, m. Having solved the equation, we obtain the value for determining the lateral pressure C,0 at the surface of the auger shaft:

e/r (b-s*) , (I)

where is the backing pressure on the tach from the window, N/m^.

From Eyrakpng.ya (II) it follows that the lateral pressure increases in the near future as it approaches the screw shaft and at the same time

it reaches its maximum value.

Let us modify expression (II) in some way, i.e. add to both sides of this ratio and divide by two, we obtain:

where ^c is the average lateral pressure in the shear zone, N/m2. .

Replaced the pressure through Ra. and substitute it into expression (9.).” we obtain a formula for determining the optimal length of the compaction zone:

Analyzing expression (13), it can be noted that the length of the compaction zone of a double-sided compression screw press with known diameters of the perforated cylinder and screw shaft depends on the force factor (), the physical and mechanical properties of the pulp

design parameter (.¿?/).

Solving expressions (7) and (13) together after transformations and substitutions, we obtain a generalized model of dehydration of potato pulp in a double-sided compression shock press:

vol. t""pVg",\rg*" 14)

where C) is an empirical coefficient;

1Lo - compressibility modulus; . .

nyaol coefficient of the Fourier series; A is a coefficient equal to u~ ;

/i ■(£>-(()

Coefficient equal to ^--

Cr - coefficient equal to SoSh-^-TsU- s.Qi))>

P - screw rotation speed, r/s; C - angle of elevation of the screw helix, degrees; Ш - angle between the direction of movement of the material and the plane

side surfaces of the auger winding, deg; EU<- среднее значение коэффициента пористости мезги. Выражение (14) описывает процесс обезвоживания картофельной мезги в шоковом пресса двухстороннего сжатия и может быть использовано при расчете пресса.

Productivity of a double-sided compression screw press.ta-

no be determined from the expression:

where X is the thickness of the pulp layer in the compaction zone, m;

- £ - screw pitch, m; £ - width of the screw channel, m; - - pulp density in the area of ​​the first turn of the auger, kg/m3.

"Analytical expressions were also obtained to determine some parameters of the screw working body.

■ 2.4. The fourth section, “Experimental study of the process of dehydrating potato pulp in laboratory conditions,” ■ presents the program, methodology and results of research into the process of dehydrating potato pulp on a laboratory model of a double-sided compressed screw ■ press.

Experimental studies using the experimental planning method have produced adequate regression models that make it possible to determine, within the limits of varying factor levels, the moisture content of the pressed pulp and the energy intensity of the pressing process in a screw press, which in named quantities have the form: for the moisture content of the pressed pulp. ...

127.73 - 2.341 - 0.247a< - 4,330л. +■ + 0,024 V/о[ц + 0,075 + 0,027а, -Л +

0.0155 UIOg - 0.043 a/ -0.119 pe (16 ^

bottom of the energy intensity of the spin process

E(/g = 62.145. - 1.0536 --0.9957 a y.- 1.0267 P + . . ". + 0.0065\K/o-a, + 0.0086 Mo-ya 0.005 a- n +

0.0046 ^ + o.oyu a* + o.oyu p& (I?)

"where is the initial moisture content of the initial pulp, %; D1 is the width" of the press exit window, we; P - screw rotation speed, rpm.

The analysis of regression models was carried out using two-dimensional sections (Fig. 4) and at the same time a complex problem was solved, in which it was necessary to find the values ​​of factors that provide a minimum of energy costs. spinning, with a high degree of dehydration of potato pulp. As a result, the following optimal parameters were obtained: initial moisture content of the pulp 90$, output window width 0.,011..,0.015 m, spinning frequency 4.0...6.0 rpm. In this case, the moisture content of the pressed material is in the lengths of 58...65$, and the energy intensity is only about

The extraction process is 0.6...0.3 kWh/t.

To check the convergence of the results of theoretical and experimental studies, Figure 5 shows partial dependencies obtained from the theoretical< 14) и экспериментальной.

window O.) and the rotation speed of the screw P. on the moisture content of the squeezed pulp and the energy intensity of the spinning process. With an initial moisture content of the pulp of 90$: --- - moisture content of the squeezed pulp; - - - - energy intensity of the spinning process.

(16) models - dehydration of potato pulp in a double-sided compression screw press. Theoretical dependencies were constructed taking into account the empirical coefficient C^ = 1.27. As can be seen from the figure, the moisture content of the squeezed potato pulp increases with increasing width of the outlet window and screw rotation speed. The presented graphical dependencies show that the convergence of the results of theoretical and experimental studies is quite high, the error does not exceed 5.0%. Therefore, the theoretical model (14) can be used to substantiate the parameters of a double-sided stack press.

Rice. 5. Dependence of the humidity of the pressed potato pulp W on the width of the exit window of the press (a) and the rotation speed of the screw P. (b): I-W0 = 90%, n = 4.25 rpm: 2- Wo "= n. = 4.25-rpm: 3-VD = SC$, OC = 0.015 m; 4-

Wo = BQ%, Ctj = 0.025 m;

Theoretical dependence;

" " - experimental dependence.

compression of it.

During the experimental studies, the dependences of the productivity of the screw press for the initial pulp, liquid and solid pressed fractions on the width of the outlet window and the screw rotation speed were also revealed.

,■ 2.5. The fifth section “Production tests, implementation of research results and their economic efficiency” presents the program, methodology and test results, provides a proposed technological scheme for the preparation of feed from by-products of potato-starch production, as well as the methodology and results of calculating the economic effect from the implementation of the developed ■ dehydrator as part of a line for recycling potato pulp for livestock feed.

Tests of a pilot production sample of a potato pulp dehydrator were carried out at the Ibred starch and syrup plant (Ryazan region). The stump press of the dehydrator had a diameter of pgepa of 0.205 and the total for the perforated cylinder was 2.0 and, on

in the loading necks of which two thickeners were installed with an internal diameter of the cylindrical part of the body of 0.04 m. During the tests, the productivity of the dehydrator, the energy intensity and the moisture content of the pressed potato pulp were determined.

Figure 6 shows the results of production tests of the dehydrator. As can be seen from the figure, when the width of the press exit window increases, the productivity of the dehydrator increases and the energy intensity of the process decreases, but at the same time the moisture content of the pressed material increases.

Analysis of the results of production tests of the dehydrator made it possible to recommend dates for obtaining dehydrated pulp with a moisture content of 70...75% at a feed pressure of the initial mixture of 0.3...O.35 Sha and a screw rotation speed of "6.,O rpm, regulation range and irin. output o;sha 0.015...O.02 and, in this case, the productivity will be 5.2...6.0 t/h,

Rgs. 6. Change in the productivity of the dehydrator (2d, the moisture content of the pressed pulp V/ and the energy intensity of the process E from

press exit window width

and the specific energy intensity is 1.6...1.25 kWh/t.

We propose to improve the technology for the production of dry and raw feed and by-products of potato-starch production in two ways, depending on the capacity of the processing plants (RLS.7). According to the first option

The suspension (a mixture of pulp and potato pulp) is divided into two fractions by mechanical dehydration: tvorda and liquid. Solid - used for feeding livestock as a substitute for root crops, and liquid is taken for further disposal. According to the second option, the takhe suspension is divided into two fractions. From the gldksya dutsi too-footnote "coagulation" a protein is released, which is gteaalaetsya in "^lztp"l-vated, and then after obzzBozyavaya ostz^tst z tze^doy g-ya::::.;:", which is Mrzhtsya in ksyolsgg a vnsupagletgya 2 where:.-"■ s,-

Fig""" 7" Scheme of the technological process of preparing feed from. by-products of potato starch production: I- pump? 2- collection; 3- pipeline; 4- dehydrator; 5- coagulator; 6-belt filter; 7- monolith former; 8- drying unit; 9- conveyor; Yu-collection-" "nick-drive.

file to a moisture content of 12...133?. The result is a complete

concentrated protein feed.

The economic effect from the introduction of the developed dehydrator as part of the line for recycling potato pulp for livestock feed will be 6,786 rubles when producing 6,000 * dehydrated feed with a moisture content of 75%. The economic effect is calculated without taking into account the reduction

reducing transport costs for delivering potato pulp to the consumer.

and production

I. Feed preparation process

It is recommended to carry out the production of by-products from potato medicinal production using two technologies. The first technology includes the separation of the initial mixture of pulp and potato juice into solid and liquid fractions, thermal coagulation of the pulp in the liquid fraction, its thickening and mixing with the original mixture, solid enrichment; irada with protein during mechanical

dehydration of the resulting mixture, formation of monoliths from the solid fraction and drying them, which ensures the production of a feed product with a high protein content. The second technology involves separating the initial mixture of meegi with potato juice using mechanical dehydration into liquid and solid fractions, removing the liquid fraction from production and using the solid fraction for livestock feed, resulting in a feed product in the form of potato pulp with a moisture content of 70$ and a content of 0. 3 k.vd. in one kilogram. The basis of these technologies is the mechanical dehydration of potato pulp.

2. A comparative assessment of dehydrators of various designs should be carried out according to a generalized criterion that takes into account the specific energy consumption to reduce a unit of moisture content of the product being squeezed. Using a generalized criterion, it was revealed that promising designs are presses with screw working bodies, operating in conjunction with devices that ensure “liquid filtration” during the movement of the suspension,

3. The design and technological scheme of the potato pulp dehydrator should include a double-sided compression screw press and centrifugal thickeners with a self-cleaning filtering surface installed on its loading necks, which ensures dewatering of the pulp in two stages by thickening and mechanical squeezing, which allows you to remove up to b from the dehydrated product % moisture. G"

The press must be made with a working body consisting of two screws with conical shafts, connected by large bases in the area of ​​the outlet window by means of a cylindrical insert that does not have a winding. Both screws must be enclosed in perforated cylinders with slots for filtering juice with dimensions of 0.25 x 5.0 mm. Between the cylinders it is necessary to place a window with an adjustable cross-section for the exit of the pressed product, and at the opposite ends there are loading necks. This design of the press allows the product to be compacted on both sides with evenly distributed pressure, thereby increasing the degree of pulp dewatering by 15% and increasing productivity by approximately two times compared to single-sided compression screw presses.

The developed generalized model of dehydration shows that the moisture content of pressed potato pulp in a double-sided compression shock press depends on the design and kinematic parameters

press unit and physical and mechanical properties of the removed product.

4. It has been established that the numerical values ​​of the coefficients of friction of potato pulp on a smooth steel surface decrease from 0.135 to 0.10, and on a perforated brass surface - from 0.37 to 0.24 with increasing spin pressure from 0.35 to 2.0 Sha. When the spin pressure increases from 0.40 to 2.83 Sha, the coefficient of internal friction of the pulp decreases from 0.66 to 0.24, and the coefficient of lateral pressure decreases from 0.9 to 0.68.

It has been established that the process of filtration of juice from squeezed pulp is significantly influenced by compression and filtration characteristics. When the spin pressure increases from 0.2 to 2.6 MPa, the filtration coefficient decreases from 60 to 0.73 * 10 ~ 9 m/s, the compressibility coefficient - from 5.13 "KG5 to 0.06" 10-6 m^/N and the press capacity module - from 1.56 to 0.17. The pulp porosity coefficient when the humidity decreases from 90 l to 52.38? decreases from 9.0 to 1.1.

5. Laboratory studies of a model of a double-sided compression screw press have shown that its design is efficient and can be used for pressed potato pulp.

Optimization of the working process of a screw press using the method of two-dimensional sections of the obtained multifactor regression models made it possible to establish that with an initial moisture content of the initial product of $90, to obtain pressed pulp with a moisture content of $58...65, the following parameter values ​​are required: screw rotation speed 4.0...6, 0 rpm; width of the press exit window 0.011...0.015 m; energy consumption only for the waste process is 0.6...0.3 kW*h/t.

6. Production tests of a pilot production sample of a potato pulp dehydrator, developed on the basis of theoretical studies and a laboratory model of the press, showed that1 the regulation of the technological parameters of the process must be carried out by changing the width of the outlet window of the screw press. With its increase from 0.01 to 0.03 m at a supply pressure of the initial mixture of pulp with potato juice of 0.30...O.35 Sha, productivity increases from 4.9 to 6.63 t/h, and the humidity of the squeezed pulp increases from 63 .37 to 77.07^, and the energy intensity of the dehydration process decreases from 1.94 to 0.8 kRT h/t.

7. For stable operation of the dehydrator in production systems for the production of potato juice and potato juice with an initial moisture content of 0, 30... 0.3? ".:~a, frequency watt;?cue screw 6.0 rpm, width of the output window

ecca O.015...0.020 m. The productivity in this case will be 5.2... O t/h, the humidity of the pressed product is 70...1Ъ% and the energy intensity of the dehydration process is 1.60...1.25 kW* h/t.

8. The economic effect of the introduction of the developed dehydrated gel as part of the line for recycling potato pulp for livestock feed Yutavit is 6,786 rubles when producing 6,000 tons of dehydrated feed with a cost of $75.

1. Hydrocyclone dehydrator. - Positive decision of the ShSE on application 4297280/31-26 dated 02.26.90, (co-authors V.F. Nekrazvich and M.V. Oreshkina).

2. Inekovny press. - Positive decision of VNIIGOZ on application BO5033/27-30 dated 10.23.89, (co-author M.V. Oreshkina).

3. Filter for separation of suspension, - Positive decision of ShZhPE on application-4657442/31-26 dated 09.22.89, (co-author M.V. Orei-ana).

4. A.o. I5I2666 B04G 5/16. Dewatering agent for suspensions, - Publ. I B.I., 1989, No. 37, (co-author M.V. Orepkina).

O. A.c. I4I99I4 CALL 9/20. Press for extracting liquid from substances - Publ. in B.I., 1988, JK32, (co-authors M.V. Oreyakina and P.I.]vetsov).

6. Justification of technologies for recycling waste from potato starch production for livestock feed // Improvement of agricultural technology used in cattle breeding. Sat. nzuch. tinder - Gorky, 1990, - P.42,..45, (co-author M.V. Oreshkina).

7. Technology and dewatering; shvatol gartotelnok pulp for feeding livestock // Contribution of young people and specialists to the intensification of agricultural production / Material of the All-Union Scientific-Pgoktyaskol Conference. ~ Alma-Ata, 1939, - P. 106.

8. Dehydration of potatoes.”lzga osadi tey.chsh dentrdfugiro-ranlem // Improvement of agricultural machinery used in livestock farming. Sat. scientific works, - Gorky, 1990.- P.29...31.

The article is devoted to a comprehensive study of the chemical composition and safety indicators of potato production waste. The main indicators that control the quality and safety of products include: the content of dry substances, ash, crude protein, starch, sugars, humidity, as well as toxic elements and microbiological indicators. Determination of physicochemical parameters was carried out in accordance with GOST 7698-78. "Sampling and methods of analysis." When processing potatoes, about 20% of the dry matter of the raw material is lost in the form of potato juice and 20% in the form of pulp. Complete recycling of secondary products helps to use potatoes more rationally and economically as an industrial raw material, and also helps to solve the problem of providing feed and significantly reduces the pollution of water bodies with wastewater from potato processing production. Based on the conducted studies, it was shown that the amount of dry substances in potato pulp and cell juice contains 14.6 and 1.5%, respectively. In addition, the chemical composition is also supplemented by vitamins such as C, PP, B9, carotene, pantothenic acid, minerals, monosaccharides and others. At the same time, the limits of change in potato moisture content in laboratory and production conditions are 86.65±4.6% and 97.4±0.85%, respectively. The content of toxic substances, as well as microbiological indicators in the pulp and cell sap do not exceed the current permissible levels. Safety indicators, including the moisture content of potato pulp and cell juice, prove that this type of product is perishable and cannot be stored for long. The results showed that the composition of potato production waste largely depends on the quality of the feedstock, thereby establishing the possibility of their use as feed for farm animals.

potato production waste

chemical composition

safety indicators

recycling

feed additive

1. Anisimov B.V. Potato growing in Russia: production, market, problems of seed production // Potatoes and vegetables. – 2000. – No. 1. – P. 2-3.

2. Anisimov B.V. Potatoes 2000-2005: results, forecasts, priorities // Potatoes and vegetables. – 2001. – No. 1. – P. 2-3.

3. Gapparov A. M. The problem of food supply for the population of Russia // Food Industry. – 2001. – No. 7. – pp. 13-14.

4. Goncharov V. D. Raw materials resources of the processing industry of the agro-industrial complex / V. D. Goncharov, T. N. Leonova // Storage and processing of agricultural raw materials. – 2003. – No. 4. – pp. 14-16.

5. Kokina T.P. Quality control and certification of seed potatoes / T.P. Kokina, B.V. Anisimov // Potatoes and vegetables. – 2001. – No. 2. – P. 6-7.

6. Kolchin N.N. Potato complex of Russia: state and development prospects // Potatoes and vegetables. – 2000. – No. 4. – P. 2-3.

7. Poznyakovsky V. M. Hygienic fundamentals of nutrition, quality and safety of food products: textbook. – 5th edition, corrected. and additional – Novosibirsk: Sib. Univ. publishing house, 2000. – 480 p.

8. Prosekov A. Yu. Market capacity of the Kemerovo region for semi-finished potato products / A. Yu. Prosekov, Ya.M. Karmanova // Food industry. – 2005. – No. 6. – P. 76.

9. Pshechenkov K. A. Suitability of varieties for processing depending on growing and storage conditions / K. A. Pshechenkov, O. N. Davydenkova // Potatoes and vegetables. – 2004. – No. 1. – pp. 22-25.

10. Stepanova V. S. Justification of the needs of the region’s population for food products // Food industry. – 2004. – No. 7. – pp. 42-43.

Introduction

One of the priority areas of the State Program for the Development of Agriculture and Regulation of Markets for Agricultural Products, Raw Materials and Food for 2013 - 2020 is the development of biotechnology and rational stimulation of growth in the production of main types of agricultural products and food production.

Food industry waste, in most cases, in moderate quantities, can be directly used in agriculture to feed animals. They have high energetic and biological activity, are harmless, hypoallergenic, and are easily amenable to enzymatic and microbiological bioconversion and various types of processing. The limiting factor, in this case, is usually the high content of water in waste, which increases the cost of transportation, limits the amount of this waste in diets and does not contribute to long-term storage of the product.

At most potato processing plants, due to the lack of recycling shops for waste processing, only a small part of it is rationally used for feed purposes. At the same time, the amount of waste is constantly growing. It is known that when processing potatoes, by-products are formed that have an increased amount of moisture. In Russia alone, the following waste from potato production is generated per year: pulp - 60-70 thousand tons, waste from the production of dry mashed potatoes - up to 10 thousand tons, wastewater - 100-120 thousand tons.

In the Kemerovo region alone, up to 600 thousand tons of potatoes of various varieties are processed daily to produce various types of products, and during the processing process, up to 30-50% of potato waste remains, from which starch can be obtained.

Despite the fact that the chemical composition and properties of potatoes and their production waste are covered in sufficient detail in the reference literature, they vary significantly in relative figures depending on various factors.

Based on the above, the purpose of this work is to study the chemical composition and safety indicators of potato production waste.

Objects of research appeared: waste from potato production (potato pulp, cell juice, starch).

When performing the work, we used standard, generally accepted and original research methods, including physicochemical: spectrophotometry, polarimetry, microscopy, refractometry. Determination of physicochemical parameters was carried out in accordance with GOST 7698-78. "Sampling and methods of analysis." The results obtained were compared with the standards and requirements for the quality of potato starch according to GOST R 53876-2010 “Potato starch. Technical conditions".

Research results

When using potato pulp and cell sap for food or feed purposes, knowledge of their chemical composition and other indicators that evaluate their technological properties is necessary. Therefore, to clarify the chemical composition of potato pulp and cell sap, research was carried out to assess their quality and safety.

Table 1 presents the limits of change in the physical and chemical properties of potato pulp and cell sap.

Table 1

Chemical composition of potato pulp and juice

Table 2 shows data on changes in the moisture content of potato pulp and cell sap obtained in laboratory and production conditions. During the research period, the limits of change in moisture content (average value) of potatoes in laboratory and production conditions were equal to 86.65±4.6% and 97.4±0.85%, respectively. The high humidity of the resulting by-products does not allow them to be stored for a long time.

table 2

Changes in the moisture content of potato pulp and cell juice

The pH value of the juice is 5.6-6.2. The high acidity of the cell sap is due to the presence of a significant amount of organic acids in the tubers. Among them are citric, malic, oxalic, pyruvic, tartaric, succinic and some other acids. There is especially a lot of citric acid in tubers (up to 0.4-0.6%).

Believing that the technological properties of biological objects are determined by the content of protein substances and amino acids contained in them, potato juice could therefore become one of the promising sources of natural plant protein. When studying cell sap in this direction, at least 12 free amino acids were found, among which there are vital amino acids: valine, leucine, methionine, lysine, arginine.

Fresh potato juice and pulp also contain vitamins such as C, PP, B9, carotene, and pantothenic acid. However, upon contact with iron parts of equipment, the content of some vitamins, especially vitamin C, in potato juice is significantly reduced compared to their content in tubers.

The ash elements of juice are widely represented. About 60% of the ash is potassium oxide. The ash of the juice contains almost all microelements. It was noted that there were no significant differences in the amount of minerals in the studied samples.

A study of cell sap carbohydrates showed that they are mainly represented by monosaccharides: glucose, mannose, fructose. The content of reducing sugars depends on the variety, degree of maturity of the tubers, growing and storage conditions. When the content of reducing sugars in tubers increases to 0.5%, the potato product acquires a brown color and a bitter taste, which are unacceptable for the final product.

During the research, the content of toxic elements, nitrates, pesticides and radionuclides in the studied samples was studied. The research results are presented in tables 3-4.

Table 3

Safety indicators of potato pulp and cell juice

Table 4

Microbiological parameters of potato pulp and cell juice

It was noted that the content of radionuclides in the pulp and cell sap does not exceed the current permissible levels. The presence of toxic substances and pathogenic microorganisms in the studied samples of raw materials and by-products of their processing was not detected. Mercury, arsenic, mycotoxins and pesticides were not detected in potato pulp and cell sap. The nitrate content in potato pulp and cell juice is on average 89.75 mg/kg.

It has been established that controlled potentially hazardous chemicals are contained in the product in concentrations not exceeding established standards and comply with the requirements of SanPin 2.3.2.1078-01 “Hygienic requirements for the safety and nutritional value of food products” and the technical regulations of the Customs Union “On the safety of feed and feed additives” "

Thus, an analysis of the literature and our own experimental data showed that the chemical composition and indicators characterizing the physicochemical and technological properties of potato pulp and cell sap are largely dependent on the quality of the feedstock. This predetermines further research on use in the food industry. The chemical composition of potato processing by-products indicates the possibility of their use as components of food products. At the same time, the main indicators of the technological properties of by-products indicate the need to use special methods for their processing or preparation.

With the introduction of innovative processing technologies and changes in demand for manufactured products, food production waste can change its social utility and become the starting material for obtaining new high-quality feed.

Reviewers:

Kurbanova M.G., Doctor of Technical Sciences, Associate Professor, Head of the Department of “Technology of Storage and Processing of Agricultural Products” of the Kemerovo State Agricultural Institute, Kemerovo.

Popov A.M., Doctor of Technical Sciences, Professor, Head of the Department of Applied Mechanics at the Kemerovo Technological Institute of the Food Industry, Kemerovo.

Bibliographic link

The method relates to feed production. The method consists of adding granulated sulfur or sodium hypochlorite solution to the crushed pulp at a consumption of 1.8-2.3 g and 420-25 ml per 1 kg of silage mass, respectively. The method allows to reduce nutrient losses. 1 table

The invention relates to livestock farming, specifically to methods for preserving feed, and can be used for silage.

Feed canning is widely used in feed production to increase the safety of feed.

Various chemicals are used as preservatives - acids, salts, organic substances. Chemical preservatives, as a result of transformations in feed, help lower the pH of the environment, inhibit undesirable microflora and produce high-quality feed.

In starch-molasses production, potato pulp is formed as a by-product - a watery, poorly transportable product, which is immediately used as livestock feed, because it quickly deteriorates or is subjected to ensiling. Due to the presence of carbohydrates in the pulp, fermentation occurs, and silage is obtained, suitable for feeding to farm animals. However, relatively high nutrient losses occur.

The technical result is the use of available preservatives to reduce nutrient losses. This is achieved by the fact that in the proposed method for preserving potato pulp, locally produced chemical preservatives are used - granulated sulfur - a waste product from the purification of petroleum products (TU 2112-061-1051465-02) at a consumption of 1.8-2.3 g/kg or sodium hypochlorite - the preparation "Belizna" after dilution with water in a ratio of 1:9 at a consumption of 20-25 ml/kg of weight.

Composition of potato pulp, wt.%:

Granulated sulfur is a hemispherical yellow granule with a diameter of 2-5 mm containing the main substance - sulfur - at least 99.5% wt. organic acids 0.01% with a bulk mass of 1.04-1.33 g/cm3.

The drug "Belizna" is a commercial product - a solution of sodium hypochlorite with a concentration of up to 90 g/l.

Under silage conditions, under the influence of enzymes and potato pulp juice, chemical transformations of sulfur occur with the formation of hydrogen sulfide, sulfites and sulfates. These compounds, as well as sodium hypochlorite, have bactericidal properties and suppress the development of unwanted microflora. At the same time, the activity of lactic acid bacteria is practically not inhibited, the silage mass is acidified, resulting in good-quality silage. The available literature contains no data on the use of chemical preservatives when ensiling pulp.

Example. In laboratory conditions, crushed potato pulp with a humidity of 80.0% is loaded into sealed containers layer by layer, granulated sulfur is added - a waste product from the production of petroleum products at the rate of 2 g/kg, in the second option - diluted preparation "Belizna" (1:9) at the rate of 20 ml /kg, in the third option - without preservatives, compacted, hermetically sealed and left for storage at room temperature. After 35 days, the containers are opened and the quality of the silos is assessed. They obtain high-quality silage with the smell of pickled vegetables with a pH of 3.9-4.1.

Zootechnical analysis showed the following results

Thus, the use of chemical preservatives - granulated sulfur or sodium hypochlorite solution - makes it possible to improve the quality of potato pulp silage and reduce nutrient losses compared to the known method.

INFORMATION SOURCES

1. Taranov M.T. Chemical preservation of feed. M.: Kolos, 1964, p.79.

2. Muldashev G.I. The influence of sulfur and the sulfur-urea complex on the quality of winter rye silos and the productivity of bull calves during fattening. Author's abstract. diss. for the job application Candidate of Science Degree agricultural sciences Orenburg, 1998.

3. Gumenyuk G.D. and others. Use of industrial and agricultural waste in animal husbandry. Kyiv, Harvest, 1983, p.15.

A method of preserving potato pulp, characterized by the fact that the pulp is crushed and chemical preservatives are added to it: granulated sulfur - a waste product from the purification of petroleum products or a solution of sodium hypochlorite - the drug "Belizna" after dilution with water in a ratio of 1:9 with a consumption of 1.8-2, respectively, 3 g and 20-25 ml per 1 kg of silage mass.

Similar patents:

When processing potatoes, a large amount of waste is generated. In potato starch production, the main wastes are potato pulp and cell juice.

The high moisture content in potato pulp (over 90%) makes it difficult to transport, which makes it difficult to sell. In favorable years, potato pulp is not completely used as fresh livestock feed and is stored in pits, which leads to large losses of nutrients (up to 30 – 35% dry matter). On farms located next to starch and syrup enterprises, fresh and ensiled pulp is fed to cattle, pigs, and poultry.

Potato pulp is sold as livestock feed in its raw form (fluid, with a moisture content of 86 – 87%). In order to facilitate transportation and disposal, it is advisable to dehydrate it. To reduce losses and increase transportability, the pulp is dried. In this case, all substances are completely preserved. 100 kg of dried pulp contains 95 feed units. It is used as a component of mixed feed. Potato cell juice contains up to 6% dry matter. However, it is hardly used. Cell sap makes up about 50% of the mass of processed potatoes.

Currently, a scheme for recycling waste from potato-starch production to produce carbohydrate-protein hydrolyzate and protein feed is being introduced into production. It allows you to use potato dry matter by 97% and reduce the consumption of fresh water for technological needs. Enriching the pulp with cell sap increases the nutritional value of the feed. Protein feed (coagulated cell sap protein) is absorbed by animals by 80%.

Full sale of raw potato pulp and juice is possible only in small factories that process up to 200 tons of potatoes per day. At larger factories, it is advisable to build recycling workshops to produce concentrated and dry feed.

When processing potatoes in the alcohol industry, the bulk of the stillage containing 3.2 – 4.1% dry matter, fed to animals. Stillage is a valuable, but watery and poorly transportable feed. Transporting it to farms by road is ineffective, as the cost of this feed increases significantly. Therefore, feedlots should be located near distilleries.

The most rational way to utilize potato stillage is to process it into feed yeast and use it in livestock farming in dry form as part of compound feed, as well as in the form of a liquid feed product. Many distilleries experience difficulties in selling stillage in the spring and summer, when the need for it due to the availability of green fodder sharply decreases.

Much attention is paid to the issue of producing liquid feed yeast, since their addition to feed rations enriches them with highly digestible protein.