Pilot Batch Research Articles

Production of synthetic high-octane gasoline from associated petroleum gas

The article proposes a method for producing high-octane gasoline from associated petroleum gas (APG), which consists of a combination of the processes of direct aromatization of APG and Fischer-Tropsch synthesis (FT). The APG aromatization process was experimentally studied in a flow-through installation at a pressure of 0,1 MPa and a temperature of 450-600 °C on a ZnO/ZSM-5/Al2O3 catalyst. It has been shown that at a temperature of 600 °C the degree of conversion of C3+ hydrocarbons is 27,8%, and the yield of aromatic hydrocarbons is 10,9 %. The synthesis of FT was studied on a hybrid Co-Al2O3/SiO2/ZSM-5/Al2O3 catalyst at a temperature of 250 °C, pressure 1,0 MPa, GHSV 1000 h-1. A pilot batch of synthetic gasoline fraction with a volume of 1 liter was produced at a pilot plant, and its main physicochemical and operational properties were analyzed. It has been shown that compounding the gasoline fraction of the FT synthesis and direct aromatization products of APG makes it possible to increase the octane number from 78,5 to 92,8 units, while the density increases from 710 to 778 kg/m3. The proposed technological solutions can be used for processing APG into high-octane synthetic gasoline using GTL modular units.

Does Air Quality Ecological Compensation Improve Total Factor Energy Efficiency?—A Quasi-Natural Experiment from 282 Cities in China

The impact of air-quality ecological compensation on total factor energy efficiency can help a country to achieve high-quality economic development with the goals of peak carbon emissions and carbon neutrality, and to explore a win–win path for the economy and the environment. This study investigates the impact of air-quality ecological compensation (AQEC) on total factor energy efficiency using the time-varying difference-in-difference model with a sample of 282 Chinese cities from 2004 to 2022. The results show AQEC significantly increases total factor energy efficiency by 1.71% in the pilot areas. This result remains robust after undergoing PSM-DID, considering only the first three pilot batches, an instrumental variable approach, the exclusion of other policies interference, and dual machine learning. The mechanisms analysis indicates that AQEC enhances total factor energy efficiency by promoting industrial structure advancement and green technology innovation. Furthermore, it is noteworthy that heterogeneity exists in the effect of AQEC on total factor energy efficiency, particularly in cities with an old industrial base and small cities. Overall, this study refines the causal relationship between air-quality ecological compensation and total factor energy efficiency, providing empirical evidence and policy insights for China and other countries to enhance energy efficiency and promote urban ecological civilization.

Immunogenicity and safety of boosting with a recombinant two-component SARS-CoV-2 vaccine: two randomized, parallel-controlled, phase 2 studies

ABSTRACT Background Recombinant protein vaccines are vital for broad protection against SARS-CoV-2 variants. This study assessed ReCOV as a booster in two Phase 2 trials. Research design and methods Study-1 involved subjects were randomized (1:1:1) to receive 20 μg ReCOV, 40 μg ReCOV, or an inactivated vaccine (COVILO®) in the United Arab Emirates. Study-2 participating individuals were randomized (1:1:1) to receive 20 μg ReCOV (pilot batch, ReCOV HA), 20 μg ReCOV (commercial batch, ReCOV TC), or 30 μg BNT162b2 (COMIRNATY®) in the Philippines. The primary immunogenicity objectives was to compare the geometric mean titer (GMT) and seroconversion rate (SCR) of neutralizing antibodies induced by one ReCOV booster dose with those of inactivated vaccine and BNT162b2, respectively, at 14 days post-booster. Results Heterologous ReCOV booster doses were safe and induced comparable immune responses to inactivated vaccines and BNT162b2 against Omicron variants and the prototype. They showed significant advantages in cross-neutralization against multiple SARS-CoV-2 variants, surpassing inactivated vaccines and BNT162b2, with good immune persistence. Conclusions Heterologous ReCOV boosting was safe and effective, showing promise in combating COVID-19. The study highlights ReCOV’s potential for enhanced protection, supported by strong cross-neutralization and immune persistence. Clinical Trial Registration Study-1, www.clinicaltrials.gov, identifier is NCT05323435; Study-2, www.clinicaltrials.gov, identifier is NCT05084989.

Use of technogenic raw materials in ceramic technology

Studies have shown that burnt rocks and ash-and-slag materials, as corrective additives, improve the properties of poor-quality clay raw materials. The possibility of using this technogenic raw material in ceramics technology for the manufacture of ceramic products for various purposes is shown. The use of burnt rocks and ash-and-slag materials improves the sintering of the shards, intensifies the crystallization of mullite-like compounds, which has a positive effect on the physical and mechanical properties of ceramic products: strength and frost resistance increase, shrinkage deformations and water absorption decrease. The use of burnt rocks and ash-and-slag materials makes it possible to obtain refractory products on loam instead of refractory clays. The results of laboratory studies are confirmed by tests of pilot batches of ceramic bricks and tiles, thin-walled ceramic products (roof tiles and artistic ceramics).

PURIFICATION OF ARCHAEOLOGICAL LEAD

The study of the complex method of deep purification of archaeological lead, developed at the NSC KIPT, is described. The obtained results on the refining and application of purified ancient lead are presented. Pilot batches of ancient Greek and Roman lead of purity >99.9996...99.998 wt.% were produced for growing perfect crystals of archPbWO4 and archPbMoO4, that are used as scintillation detectors for recording rare events in modern lowbackground experiments. The most interesting experiment is RES-NOVA aimed at detecting neutrinos from astrophysical sources such as supernova (SN) collapse using cryogenic detectors made on the basis of archeological lead (archPbWO4). A method of oxidizing refinement of metals is proposed, which can be used for additional removal of chemical and radioactive impurities U, Th, 40K from lead.

Fast-activating reserve power sources: is lead dead indeed?

The purpose of this research is to improve the performance and reduce the activation time of reserve power sources based on lead-acid systems at lower temperatures, down to –50 °C. Physico-chemical factors affecting the activation speed of reserve power sources based on Pb–HClO4–PbO2 and Zn–HClO4–PbO2 systems are investigated using chronopotentiometry, scanning electron microscopy, and standard contact porosimetry. Two approaches to the improvement of the low-temperature performance of power sources are used. The first one is based on the substitution of lead as anodic material with zinc. This allows the increase in discharge voltage and simultaneous decrease in activation time, but brings about the instability of discharge characteristics and, finally, deteriorates the reliability of power sources. The second approach is based on the use of PbO2 cathode material with enhanced nanoporosity. The chronopotentiometric method in galvanostatic mode is applied to the quality estimation of cathodes. The criterion of applicability of cathodes for reserve power sources consists in the low discharge overvoltage (0.1–0.2 V). Efficient performance of reserve power sources possessing the stable discharge voltage (1.5–1.8 V per cell) and the unprecedentedly short activation time (under 30 ms) even at lower temperatures (down to –50 °C) is achieved. The results are verified by fabrication and testing of pilot batches of miniaturized reserve power sources having microcells’ volume of 0.02 ml. The second approach to the improvement of power sources is transferred into the industrial production.

USE OF BIOLOGICALLY ACTIVE SUBSTANCES IN AGRICULTURAL PREPARATIONS

Introduction. The production and use of growth stimulants, both as single preparations and in combination with traditional organo-mineral fertilizers, is of great scientific interest and practical significance. In this connection, one of the most promising approaches to solving this problem is the development of preparations based on plant growth regulators, including both biostimulants obtained by microbiological synthesis and biostimulants obtained by chemical synthesis. Purpose. To develop a growth-stimulating preparation using non-traditional raw materials and test it in laboratory and field conditions on pilot batches of barley and wheat seeds encapsulated with the preparation being studied, which contained the following components: sodium humate, hydrated fullerenes, an aqueous solution of shungite, microbiological carotene in a certain ratio. Methods. Laboratory and field experiments to study the effect of the application of preparations with different components on the growth and development of barley and spring wheat were carried out on the basis of V. Dokuchaev Kharkiv National Agrarian University at the Department of Plant Growing in 2020. Results. The results obtained during laboratory experiments showed that the application of the preparation "Humyr" had a stimulating effect on the growth of plants. Seedlings in the test variant appeared a day earlier than the control ones, and the plants of the test variant were ahead of the control ones in development. At the end, the average length of seedlings was 9.5 cm in the control, and it was 13.8 cm in the test. The average mass of seedlings was 1.6 g in the test. Thus, in the preliminary laboratory experiments it has been shown that the application of the preparation at the first stages of plant growth had a stimulating effect, ensuring an increase in the length and mass of seedlings in the tests compared to the control ones. Conclusions and perspectives. Research and development of new non-traditional preparations which, along with known plant growth stimulants, increase the productivity of crops in food production were carried out. The developed preparation “Humir”, in addition to increasing the yield of grain crops, had good wettability and a film-forming effect. After spraying, it caused a creation of thin film on the surface of the leaf, which was being absorbed by the plant for several days. Because of this, “Humir” can also be successfully used to combat diseases such as powdery mildew, late blight, bacteriosis, etc.

ВЫПУСК ОПЫТНО-ПРОМЫШЛЕННЫХ ПАРТИЙ КРИОЛИТА С ИСПОЛЬЗОВАНИЕМ ХЛОРИДА И ГИДРОКСИДА НАТРИЯ И ИХ ИСПЫТАНИЯ ПРИ ПРОИЗВОДСТВЕ АЛЮМИНИЯ

The paper presents the results of pilot batch production of cryolite using sodium chloride and sodium hydroxide by hydrochemical method, physical and chemical studies of the obtained products, as well as their testing in aluminium electrolysers with measurements of technological parameters before and after use. The conducted studies have shown that the process of production of a pilot batch of cryolite by hydrochemical method from hydrofluoric acid using aluminium hydroxide, sodium chloride and sodium hydroxide solutions proceeds at a temperature of 25 °C for 30-45 min. In this case, the yield of cryolite according to the first embodiment using sodium chloride is more than 80 %, since during the reaction a side hydrochloric acid is formed, which dissolves more than 15 % of the cryolite. When sodium hydroxide is used, the process proceeds similarly to the first variant with an increase in cryolite yield of more than 90%. According to pilot tests, the first variant produced 600 kg of cryolite and the second variant produced 620 kg of cryolite. The reliability of the process of cryolite production with the use of sodium chloride and hydroxide was confirmed by chemical and X-ray phase analyses using the modernised Dron-2 unit. It was found that the analysed samples correspond to the reference cryolite, indicating the interaction of sodium chloride and sodium hydroxide with fluoroaluminium acid. Also the obtained synthetic products have successfully passed pilot tests in aluminium electrolysers of JSC "TALCO" with control of technological parameters. On the basis of conducted researches the basic technological scheme of cryolite production by hydrochemical method with application of hydrofluoric acid, aluminium hydroxide, sodium chloride and hydroxide was developed. As a result of the research it was found out that the technology of cryolite production with the use of sodium chloride and hydroxide is easy to implement and cost-effective due to low energy consumption of production and the use of local mineral raw materials.

Activities of JSC “The Ukrainian research institute of refractories named after A. S. Berezhnoy” in the field of refractories standardization in 2021—2022

In 2021, JSC “URIR named after A. S. Berezhnoy” institute carried out scientific, scientific­technical, and organizational activities in the field of development, verification of national standards for refractories harmonized with ISO standards, provided scientific, methodological, information, and consulting services to provide regulatory documentation at the request of refractory enterprises of Ukraine.
 The Institute organized and coordinated the activities of the Technical Committee for Standardization “Refractories” (TC 7), prepared work plans and reports on the work performed by the TC 7 in 2021, and submitted them to the National Standardization Body — SE “UkrNDNC”.
 In 2021, JSC “URIR named after A. S. Berezhnoy” institute developed five technical specifications (TSs) for serial refractory products manufactured by refractory enterprises of Ukraine. Six technical specifications and eight changes to the current TSs for pilot batches of refractory products manufactured by the Institute were developed.
 The technical specifications and changes to the technical specifications were developed in accordance with the requirements of the modern standardization system of Ukraine, agreed upon with the enterprises — producers, as well as consumers, and checked for compliance with current legislation, technical regulations, as well as normative documents, and entered into the database “Technical Specifications of Ukraine” — SE “Kharkivstandartmetrologiya”, approved by the Technical Committee for Standardization “Refractories”.

РАЗРАБОТКА БЕЗЗОЛЬНЫХ ПРОТИВОЗАДИРНЫХ ПРИСАДОК

The physicochemical and tribological parameters of the ash-free additives obtained in the laboratory are given. It is shown that they have high extreme pressure properties and low ash content. The results of comparative laboratory tests of tribo-engineering characteristics of new additives of Russian and foreign production are presented. It is found out that the new additives in terms of maximum load capacity are not worse than imported analogues and can be used to increase the extreme pressure properties of lubricants for various purposes (including ash-free ones) instead of their imported analogues. A pilot batch of additives containing 45% sulfur is prepared and tested.

Medical and biological justification for the use of venison in special food products

Data on the biological and nutritional value of venison have been studied. Justification for the use of venison and the development of meat cream using it has been carried out in KubSAU named after I.T. Trubilin. As a result of the research, the venison market in Russia has been analyzed, and to substantiate the biotechnological requirements for the composition and quality of meat cream intended for feeding residents of the Far North have been substantiated; quality characteristics of the main raw material – venison and additional raw materials have been selected and assessed. Using the method of calculating quantitative and qualitative characteristics of the selected ingredients, the combination of formulation components that enrich the developed product with natural biological elements has been determined. The recipe composition of meat cream based on venison has been modeled. Pilot batch of meat cream has been developed with subsequent assessment of nutritional and biological value. A study conducted on the Daily supply of the main nutrients of the developed special-purpose meat cream, provided for the social group of people (residents of the Far North) has been studied and it has been revealed that the body’s energy costs are 15% higher, and the need for protein and fat consumption also increases to 140 g. Moreover, it has been revealed that the product is rich in vitamin B, which fully meet the daily requirement, vitamin A, which provides up to 29.3%, and vitamin C, up to 38% of the daily requirement. The developed meat cream meets the protein content requirements of 15.3%; fat of 19%; salt of 2%.

Development and research of technology for obtaining welding wire from aluminum-silicon alloys using rolling-extrusion

The article presents the results of research that make it possible to solve a significant scientific problem associated with the creation of new technologies for processing hard-to-deform aluminum-silicon alloys. For this purpose, tasks were set and solved for the development of technological schemes for obtaining longish products from AlSi12 and AlSi5 alloys using the methods of electromagnetic crystallization ingots of a small cross-section and the manufacture of deformed semi-finished products in the form of rods and wire using the method of combined rolling-extrusion (CRE) and drawing. To solve these problems, the modeling of the CRE process, theoretical and experimental studies were carried out, the results of which made it possible to obtain pilot batches of welding wire from the AlSi12 alloy, the level of properties of which meets the requirements of current standards. To analyze the combined rolling-extrusion, modeling was carried out using the DEFORM 3D software package. Regularities were established for changing the temperature-rate and force parameters of this process along the deformation zone. Since the use of the proposed technological scheme for the combined processing of aluminum-silicon alloys leads to a decrease in labor intensity and production costs, it can be recommended for use in industry to obtain longish products from them.

Self-Reliance Therapy: Reflections and a New Model

Background: Using the learnings and reflections from their professional and personal journeys, the authors believe that every “Neurosisoriented” mental health concern has four root causes: self-love (a lack of it), fear, grief, and aim (a lack of it). Using this as the premise, the authors have developed a new therapeutic modality that incorporates 12 primary universal formulas that they have conceptualized. Methods: This novel therapeutic model was implemented on 5 pilot batches, and was delivered to a total of 50 clients. The clients were from the upper-middle class section of Indian society, and their ages ranged from 21 to 58. Outcomes: Every participant had their own unique breakthrough moments over the three days of the implementation process. Further qualitative and quantitative research is needed before this new modality can be claimed as beneficial. Interpretation: This modality can be used in both group as well as individual settings, and even implemented in a group, the structure of this modality enables each participant to have a personalized experience.

Validation of a Bovine Viral Diarrhea Virus (BVDV) absolute quantification method by digital droplet PCR (ddPCR).

A increasingly common way for the diagnostics of viral agents is to carry out PCR from biological samples, which can detect their nucleic acid during the acute phase of the disease. Taking into account the need for quality control of PCR tests in laboratories accredited by ISO/IEC 17025:2017, we intend to carry out feasibility studies for the production of Reference Materials (MR) for these molecular tests, using BVDV in the matrix serum as a model. The first step for this goal was the validation of an analytical method for quantification of viral RNA to characterize the material under study. Primers and probe from a commercial qualitative assay kit designed for Real Time RT-PCR (VetMax Gold BVDV - Thermo Fisher) were used for quantification of BVDV by ddPCR. The technique was optimized and a Detection Limit of 13 copies/μL was determined, allowing a Quantification Limit of 38 copies/μL. The method showed to be linear over two orders of magnitude. The method will be used in the homogeneity study and long-term stability tests for the pilot batch of BVDV in Fetal Bovine Serum MR, a model for the production of MR intended for PCR of BVDV and other Flaviviridae.

Synthesis of cellulose nitrates from Miscanthus × giganteus var. KAMIS cellulose obtained under pilot production conditions

The work is devoted to the study of a novel national raw material resource Miscanthus × Giganteus var. KAMIS, which is positioned as one of the most promising natural sources for obtaining high-quality cellulose for the purpose of its further chemical functionalisation. A batch of technical cellulose isolated from raw materials under pilot production conditions using the nitric acid method having a cellulose content of 50.2% was characterized by high α-cellulose mass fraction (92.8%) and degree of polymerisation (1200) values. On the basis of the pilot batch of technical cellulose, a sample of cellulose nitrates offering basic functional properties was obtained: mass fraction of nitrogen – 11.18%; viscosity – 48 MPa·s; solubility – 94%. The synthesised sample is characterized by extremely high solubility in acetone, confirming the production of cellulose nitric acid esters, and a high yield of 150%. IR-Fourier spectroscopy was used to identify the main functional groups in the experimental batch of technical cellulose (3384, 2902, 1639, 1428, 1370, 1319, 1161, 700–500 cm-1) and in a sample of cellulose nitrates (1659, 1278, 834, 746, 683 cm-1). Acorresponding affiliation to cellulose and cellulose nitric acid esters was established. The structural and morphological features of the fibres of the experimental batch of technical cellulose and a sample of cellulose nitrates were characterised using scanning electron microscopy. Combined methods of thermogravimetric and differential thermal analyses were used to establish high initial temperature (197 °C) and specific heat of decomposition (6.92 kJ/g) values at the beginning of intensive decomposition. The obtained results substantiate the possibility to chemically functionalise cellulose isolated from a new alternative source into cellulose nitric acid esters with satisfactory functional properties.

Development of Isotopic Reference Materials for <sup>13</sup>C-Urea Breath Tests

Over 30 standards and certified measurement techniques are currently used in Russia to determine carbon, oxygen, and hydrogen isotope ratios. The techniques implemented in these documents are based on foreign reference materials (RMs). Similar domestically-produced RMs are not available, which makes the use of these techniques limited in the near future. This study aims to develop a certified RM (CRM) for the isotopic composition of carbon dioxide for 13C-urea breath tests. The following objectives were formulated: to develop a technique for obtaining RMs; to manufacture an RM pilot batch; to carry out type approval tests. The RM was manufactured by gravimetric mixing of carbon dioxide of two different isotopic composition from different sources with synthetic air. The mixing ratio was calculated using a specially developed technique. The RM stability was tested by an accelerated aging procedure. Following type approval tests, the developed CRM was included in the Federal Information Fund for Ensuring the Uniformity of Measurements under the registration number GSO 11999–2022. The practical significance of the obtained results is related to the possibility of using the developed CRM for improving the accuracy and validity of 13C-urea breath tests. Compared to the analogs, the developed CRM demonstrates a higher chemical purity.

Simulation of gas dynamics of oxygen flow and hydrodynamics of cooling water flow in tuyere tips with tangential optimized nozzles and results of their pilot tests.

The blowing mode largely determines the technical and economic indicators of BOF smelting, which was confirmed during the technological audit of the BOF shop of Azovstal Iron and Steel Works, carried out in 2021. It was found that the blowing mode of the process using an oxygen lance of the basic design was noticeably shifted from the optimal one in the direction of “hard” blowing. In a significant number of melts this led to an increase in the specific consumption of metal sheets, deterioration of lime assimilation by slag, dephosphorization and desulphurization of the metal. Taking into account that adjustment of the blowing mode by changing the working height of blowing and oxygen consumption did not provide a stable positive result, changes were made in the design of the tuyere tip. The design of the head with tangential arrangement of nozzles is proposed to “soften” the blowing of melts. The advantages and dis-advantages of oxygen lances of this type are considered. Numerical modeling of the gas dynamics of the oxygen flow and the hydrodynamics of the flow of cooling water in a tip with a tangential arrangement of nozzles has been per-formed. On the basis of simulation results, two variants of an improved design of the tips of 350-t LD converters with five (variant 1) and four (variant 2) main peripheral tangentially oriented nozzles and a central nozzle of lower throughput were developed to use them mainly in the second and first periods of the campaign according to the lining of the converters, respectively. It is shown that the design parameters of the nozzle blocks provide an oxygen jet outflow regime close to the design one in the main range of oxygen operating flow rates and a “non-separated” outflow regime with a decrease in the off-design ratio down to 0.8. The design parameters of the cooling system provide both an acceptable loss of water pressure in the head (0.9 MPa), the absence of local low-speed vortex zones of water, and a fairly high average coolant flow rate along the most heat-stressed (the lower) surface of the tip (about 4.5 m/s). As a result of industrial testing of a pilot batch of experimental heads with five main peripheral tangentially oriented nozzles, manufactured at the plant’s own repair and mechanical base, an increase in the resistance of copper tips was found to be 1.2 times, the resistance of lances to removal for cleaning from accretion was found to be 6.8 times, reduction in the specific consumption of metal charge by 0.9–5.6 kg/t, an increase in the dephosphorization and desulfurization coefficients of metal in the converter by 0.7–1.5 and 1.3–3.2%, respectively.

Technological research of process for producing titanium rich slag and complex titanium-containing ferroalloy

This paper demonstrates the results on the experimental smelting of the titanium rich slag and complex titanium-containing ferroalloy under the large-scale laboratory conditions that simulate industrial one. The technological researches of the process were performed on an ore-thermal furnace with 200 kVA transformer power. The titanium rich slag was produced from the low-grade ilmenite concentrate, i.e. the low TiO2 content and the high content of impurities. During the production of the high-grade titanium slag (TiO2 content: 75–80%), the impurity elements are transferred into the associated alloyed metal (cast iron). Thus, it can be used to smelt the steel. As a result, samples of titanium slag have been produced with the content of the main components, %: TiO2 – 80.2; Al2O3 – 4.5; SiO2 – 1.97; Cr2O3 – 1.3 and Fe2O3 – 9.87. Then, in metallurgical practice a complex titanium-containing ferroalloy was first smelted from the previously produced titanium rich slag using a carbothermic approach. The high-ash coal was applied as a carbon-bearing reducing agent. The ash was more 45%. As a result of tests, a pilot batch of the alloy was produced with the following chemical composition, %: Ti - 20–25; Si - 35–45; Al - 10–15; C - 0.2–0.5; P - no more than 0.08; and ferrum. The main component content in the produced alloy suggests that it can serve as an alternative to a mechanical mixture (FeSi45, aluminum shavings, low-percentage ferrotitanium) for steel alloying and deoxidation purposes.

DEVELOPMENT OF TECHNOLOGY FOR OBTAINING EXTRACT OF ZERAVSHAN THYME (THYMUS SERAVSCHANICUS KLOKOV) AND ITS STANDARDIZATION

S.D. Asfendiyarov KazNMU has developed an original technology for obtaining Zeravshan thyme extract. A method for obtaining the extract using ultrasound with a regulated frequency is substantiated, which makes it possible to get the maximum yield of biologically active substances from medicinal plant materials with established pharmaceutical and technological parameters. The technology of three pilot batches was transferred at the pharmaceutical company FitOleum LLP to GMP. Technological process validation was successful. Technological regulations for production, quality specification «Seravshan thyme liquid extract» and a draft regulatory document have been developed. Studies have begun on long-term stability testing of the product. The developed method for obtaining the extract is patented (patent No. 6830 dated February 4, 2022).

Effect of extrusion process parameters on pellet crumbliness in fish feed production

The article presents the results of studying the pellets crumbliness index of a pilot batch of extruded compound feed for pike-perch. The regimes of extruded pellets fish compound feed production with minimal crumbling were defined using a mathematical model. A 3-factorial central composite design was implemented to obtain a mathematical model of the process of extrudate resulting in the second-degree polynomial. The process influencing factors include the feed mixture moisture W (%), extrusion temperature T (°C) and steam pressure P (MPa). Experimental studies were conducted according to the experimental plan. The experimental data obtained were entered into the planning matrix. Experimental data was processed in a program prepared in Microsoft Excel. As a result, an adequate second-order mathematical model describing the dependence of the crumbliness index on the feed mixture moisture before extrusion, extrusion temperature and steam pressure was obtained. The mathematical model adequacy was tested based on Fisher's variance ratio. The Fisher criterion is an important statistical tool for verifying the adequacy of the model and analyzing the variance. The analysis of the obtained model and its graphical interpretation are presented. A good extrusion process mathematical model was developed. The fundamental principles of feed mixture processing on a single-screw extruder and the choice of its rational parameters ensure the production of extruded compound feed pellets for pike-perch with minimal crumbling were studied. A minimal crumbling is provided at the following values of the factors - feed mixture moisture before extrusion is 32%, extrusion temperature is 132 °C, and pressure is 0.4 MPa. In the selected levels of factors, the calculated value of extruded pellets crumbling was 1.02%.