Zero-waste Technology Research Articles

Peculiarities of proteins fractionation at electroactivation of whey

Food processing, which generates both by-products and waste, requires a revision of modern processes in the framework of the development of non-residual, environmentally friendly processes. Dairy by-products require the development of complex zero-waste technologies. Electroactivation is an emerging process to overcome those challenges, which allows for non-residual processing of milk by-products. Electroactivation, managing both the technological regimes and the geometric/technical parameters of the electrolyzers used to process different types of whey, allows both the electrofractionation of the whey proteins recovered in protein mineral concentrates enriched, under certain process conditions, with a certain protein content, but also the simultaneous isomerization of lactose into lactulose following two mechanisms, and creating a closed process cycle. The geometry of the electrolyzers and the content of the secondary liquid (anodic liquid) influence both the extraction and the formation of protein compounds enriched with alpha-lactalbumin, as well as the formation of a complex between calcium and isomerized lactulose.

The Implementation of Lean Manufacturing on Zero Waste Technologies in the Food Processing Industry: Insights from Food Processing Companies in Kosovo and North Macedonia

This study aims to investigate the impact of lean manufacturing (LM) practices in the food processing (FP) industries of Kosovo and North Macedonia. It focuses on examining the effects of LM practices on operational performance metrics and evaluating the challenges and opportunities in integrating lean principles with zero waste (ZW) technologies and sustainability objectives. A qualitative multiple case study approach was used to examine nine case studies from companies in Kosovo and North Macedonia, with four companies from Kosovo and five from North Macedonia. Semi-structured interviews, guided by themes derived from a comprehensive literature review, facilitated in-depth discussions on lean practices and their influence on operational metrics and ZW technologies. For analyzing the qualitative data, a thematic analysis approach was employed, involving a multi-step coding process that ensured a comprehensive exploration and interpretation of the data. The thematic analysis uncovered that LM practices, such as Just-In-Time (JIT), Total Productive/Preventive Maintenance (TPM), Statistical Process Control (SPC), and employee involvement, considerably improve efficiency, quality, and responsiveness. The results demonstrate a close relationship between LM practices and sustainability goals, especially in waste reduction and resource optimization. Identified challenges include organizational resistance to change and resource constraints, while opportunities for improvement were noted in employee involvement, supplier engagement, and continuous improvement initiatives. This study underscores the potential of LM methodologies to boost operational performance, foster sustainability, and tackle specific challenges within the industry, offering key insights for enhancing sustainable food production in both Kosovo and North Macedonia.

Development of the wastewater treatment technology for the mine ‘Ternivska’ of the Kryvyi Rih iron ore plant

ABSTRACT Wastewater treatment in mining and mineral processing technology is a topical problem worldwide. The purpose of this study is to substantiate and develop the technology of complex wastewater treatment for the mine ‘Ternivska’ of the Public Joint Stock Company ‘Kryvyi Rih Iron Ore Plant’ with the production of highly purified water suitable for secondary use or ecologically safe discharge into surface water bodies. The proposed technology is based on the sequential application of the following stages: preliminary treatment of contaminated mine waters by coagulation and soda-lime softening methods to remove hardness, suspended solids, and colloidal substances; desalination via reverse osmosis; evaporation and crystallization of reverse osmosis concentrate in a vacuum evaporation unit; dehydration of salt sludge in a centrifuge with drying of salt crystals in a dryer. The treatment of mine water with an initial salinity of 80 g/L will give an annual effect of 1357 thousand m3 of desalinated water with a mineralization of up to 100 mg/L and 739.6 tons of mineral salt mixture. The purified water can serve as an additional source of fresh water for technological needs in industry or alternative purposes. The obtained solid salt product can be used as an alternative reagent for water-softening processes. In general, the proposed processing of mineralized mine water can be considered a zero-waste technology with clean water production and by-product utilization.

Processing Orchard Grass into Carbon Bio Pellets via Hydrothermal Carbonisation—A Case Study Analysis

The presented case study evaluates the environmental and economic effects of carbon bio pellet production from orchard grass by Farmutil HS Inc. through the hydrothermal carbonisation method, using obtained biofuel as a substitute for natural gas for heat production. Hydrothermal carbonisation is a zero-waste technology that produces renewable bioenergy by substituting fossil fuels for non-renewable resources. Processing 60,000 t/y of orchard grass with this method resulted in a total amount of heat production of 456,780 GJ/y. This means that over 60% of the energy produced from natural gas could be substituted by renewable bioenergy. It is also very important that the estimated cost of heat produced from carbon bio pellets is 29% lower in comparison to the cost of heat produced from natural gas

Sustainable synthesis and manufacturing of silver powder-based metal clay for zero-waste technology applications

In this work, information on the metal clay technique is presented. Silver clays with different metal powder content were produced, and their selected properties were examined. The research part was divided into two parts. In the first part, silver powder was produced by solid state hydrogen reduction. The average particle size of the resulting silver powder falls within the range of 0.5 to 4.5 μm. Next, seven silver clays with different powder to binder ratios were made. Then, samples for testing were prepared from the commercially available silver clay. In the second part, tests of the samples were carried out. The susceptibility of clays to shaping, density, hardness and roughness were examined. A sample with 1% methylcellulose showed a roughness of less than 1 μm. The shrinkage value ranged from more than 30% to less than 5% for the highest and lowest methylcellulose clays, respectively. Tensile strength ranged from 90 to 100 MPa for samples with lower methylcellulose content in the clay and from 30 to 80 MPa for samples with higher methylcellulose content. The highest electrical conductivity was achieved for samples with the lowest content of methylcellulose, reaching almost 80% of the conductivity of bulk silver. The microstructure of the powders and the produced samples were tested. Recycling reactions of reactants have been postulated, to obtain sustainable production by-design. A holistic sustainability assessment is quantified using circular and green metrics as well as life cycle assessment. A material circularity indicator (MCI) of 0.50 and an E-factor of 0.29 were determined, generating environmentally relatively harmless water (84%) and green gases such as O2 and H2 (7%) as waste/by-products. The cost of producing 1 kg of silver powder utilizing the closed-loop technology presented in this paper amounts to €1103.45.

Zero Waste Technology of Soybeans Processing

Soybean can be easily digested and is a valuable substitute for animal protein in various applications. That is why soy products are a very important component of a vegan and vegetarian diet. During soymilk processing, large quantities of by-products are generated. Hardly anyone knows that every kilogram of dried soybeans processed into soymilk or tofu gives about 1.2 kg of soybean curd residue, namely, okara, often regarded as a waste. Acting in the spirit of zero waste, a soybean processing technology has been developed that does not generate waste. The developed technology consists of obtaining soymilk followed by filtration to remove the insoluble residues (okara), preparing okara and fermenting to obtain vegan soft cheese. Samples analyzed for physical, chemical, and organoleptic properties. Also, the microbial quality of the obtained products was tested. Soy products produced with the proposed zero waste technology were assessed by the sensory panel and received very good marks. Fermented soy products are characterized with high levels of Lactobacillus spp. (105–108 cfu/mL), thus consuming them can bring health benefits. Cheese made from okara can be an alternative to cheeses currently obtained from soymilk.

Pulp from Colored Potatoes (Solanum tuberosum L.) as an Ingredient Enriching Dessert Cookies.

Freeze-dried pulp from colored potatoes, obtained after starch isolation, is a rich source of polyphenols. Therefore, it can be used to fortify cookies, contributing to a reduction in industrial waste, aligning with the zero-waste technology. The purpose of this study was to analyze the effects of adding 5% and 10% pulp from two varieties of colored potatoes on the content of polyphenols, antioxidant activity, physical characteristics, nutritional composition, and the levels of hydroxymethylfurfural and acrylamide of the fortified cookies. The findings revealed that colored potato pulp is an outstanding additive for fortifying cookies with polyphenols, flavonoids, anthocyanins, and flavonols (even two to four times in comparison to control). Cookies containing pulp exhibited even two times higher fiber and protein content (up to 17% more), while the fat and ash content remained unchanged compared to control cookies. Furthermore, they contained 30% less HMF and 40% more acrylamide. These cookies also exhibited good physical properties in the final products. The study demonstrated that pulp from the "Magenta Love" potato variety was significantly more effective in enriching cookies with health-promoting compounds and nutrition value compared to pulp from Marleta Blue.

Life-cycle carbon emissions from pilot zero-waste technologies in China

While low-carbon development and low-waste development are being pursued in numerous countries, it is crucial to integrate the benefits of carbon emissions reduction and economic costs to comprehensively evaluate the effectiveness of Zero-waste City technologies (ZWTs). This study provides a system accounting framework for estimating the life-cycle carbon emissions of the ZWTs. It is based on the hybrid method as a combination of the process analysis and the input-output analysis. The indicators of net carbon emissions, carbon emissions reduction, and net economic cost after accounting for carbon emission reductions are proposed to evaluate the integrated efficiency of the ZWTs. Based on the detailed input and output inventory of the ZWTs and the carbon emission intensity database of China, case studies are carried out to calculate the life-cycle carbon emissions of the pilot ZWTs in China. These technologies are divided into three categories as the technology to treat sludge, to treat domestic waste, and to treat mixed waste of sludge and kitchen waste. The results show that most of the pilot ZWTs have co-benefits of mitigating climate change while reducing solid waste. Among them, the dry anaerobic fermentation technology and the cement kiln co-processing technology are shown superior to similar technologies in terms of carbon emission reductions. After integrating the carbon emission reduction benefit to the economic cost, the sludge resource treatment technology and the grate domestic waste incineration technology are revealed cost less than the comparable technology. Finally, due to China's active promotion of renewable energy power generation to replace traditional coal-fired power generation, it is expected that the emission reduction capacity of sludge ZWTs will increase by 12.54% to 26.51% by 2035.

The Utilization of Jackfruit (Artocarpus heterophyllus L.) Waste towards Sustainable Energy and Biochemicals: The Attainment of Zero-Waste Technologies

The valorisation of food and fruit wastes has the potential for the production of sustainable energy and biochemicals. Approximately 70% of the weight of the original jackfruit (Artocarpus heterophyllus L.) fruit is lost during its processing as waste in the form of peeled skin and core, both of which have not been utilized and, thus these contribute to disposal as well as pollution issues. The major components such as cellulose and hemicellulose can be easily biologically transformed into bioenergy sources such as ethanol, methanol, and butanol; valuable phenolics and biotechnological products such as pectin, citric acid, bromelain, ferulic acid, and vanillin; and many other products. These residues can also be utilized as essential sources for the biological transformation process, leading to the production of numerous products with added value, such as phenolic antioxidants, phenolic flavour compounds, and organic acids. Thus, the value addition of jackfruit waste can support sustainable solutions towards food and nutritional security. In this way, zero waste can be achieved through novel biorefineries, which are critically highlighted in this paper. Furthermore, novel technologies for the conversion of jackfruit waste are summarized with recent findings.

28th Conference of the Faculty of Power Engineering and Power Machines at Technical University of Sofia - InnoEE 2023 17 – 19 May 2023, Sofia, Bulgaria

IntroductionThe conference is organized by the Faculty of Power Engineering and Power Machines at the Technical University of Sofia, Bulgaria. This is the 28th annual edition of the event, part of the “Days of Science” activities at the Technical University of Sofia. For the past 28 years, this conference has become a traditional annual scientific forum for the meeting of Bulgarian and foreign experts and industry representatives in the field of energy and renewable energy technologies, thermodynamics, heat engineering, building efficiency improvements and HVAC systems, environmental engineering and protection, hydraulics and pneumatics, textile and sewing production.All received publications are peer reviewed and traditionally, the highest quality scientific papers are further submitted for publishing in referenced partnering journals. Based on recent years of experience, the conference offers on-site and online possibility for attendance. The program includes keynote lectures from selected popular topics in the presented areas, as well as oral presentations of the papers by the participants. It became a tradition, for some of the main sponsors, to organize special demonstration stalls in the conference area, where they can expose their latest innovative products and have a closer meeting with the audience.This year, three exhibitions were organized and performed as side events, during the conference days. The first one is called “EcoSynthetic”, and it is an exposition of nine woodcrafter sculpture artists, developing the “energy concept” in their work. The second exposition presented students’ design ideas for devices or technologies for green and sustainable energy utilization. And finally, a small textile exhibition with textile products, developed with sustainable and zero-waste technologies, was demonstrated during the conference days.List of Organizers, Venue, Conference topics, Committees, Editors, Sessions, Participants, Sponsors, Contacts, Conference pictures, Conference Program, Conference Agenda are available in this pdf.

Analysis of Waste-Free Processing of Dairy Raw Materials Implementation Issuesin Industrial Conditions

Topicality. Today, the existing innovative developments of dairy food products have great opportunities for the wide implementation of various types and quality of dairy raw materials into production. After all, many inventions directly relate to technologies for the production of fermented milk products, bakery and confectionery products, beverages, health products, etc. This requires the use of a certain type of dairy raw materials. The problem is that there are many such products, and with the increase in the production capacity of food enterprises, there is a necessity to enlarge the number of implementations of the production of dairy products. Currently, in food industry, the number of such implementations which would provide our population with the necessary amount of scarce animal protein is insignificant. In addition, under such circumstances, people’s nutrition becomes too unbalanced, especially in the winter season. An equally important problem of new waste-free technologies implementation is a weak experimental base for creating new competitive equipment in laboratory conditions. The developed model of the process, equipment or the entire line will not have a sense without the implementation of cer tain investment contributions. The aim of this article is to reveal the main points, to choose the optimal solutions for the complex waste-free processing of dairy raw materials, and to avoid crisis situations, as well as to highlight the most precise directions in which the improvement of the general process itself should be carried out, to provide some explanations and suggestions for avoiding the main problems in the field of processing dairy raw materials. Research methods: analytical, standard generally accepted physical and chemical, as well as monographic, analysis and synthesis, classification. Results. An analysis of technological, technical and organizational issues is provided, the solution of which will allow the implementation of innovative solutions for waste-free processing of dairy raw materials in the conditions of food industry. The qualitative indicators of protein-carbohydrate dairy raw materials for further implementation in the production of dairy products are shown, and the needs of future production in another raw materials base are analyzed. Taking into account the seasonal distribution of usage in waste-free production of certain types of raw materials will ensure its reliable and stable operation with the simultaneous expansion of the final products range. A variant of technical equipment of the future zero-waste production for the processing of dairy raw materials and its maintenance is developed. A clear and well-considered choice of technology and equipment for modernization or creation of new lines of waste-free processing of dairy raw materials and means of its sanitary processing will allow to increase the competitiveness of final products and bring production to a modern level. Conclusions and discussion. A number of issues that must be taken into account when organizing a future enterprise for the production of dairy products using zero-waste technologies are presented. An analysis of investment needs for the development of the chosen direction for the effective organization of the future milk processing enterprise is provided.

Rеsеаrch on Еcologіcal and Еconomic Dеvеlopmеnt and it is Impact on Еcology

Abstract. Introduction. The beginning of the 21st century for the world population became an obvious approach of a global catastrophe associated with large pollution of the natural environment, the destruction of the ozone layer of the biosphere, the increase in climate change, and the dangerous degeneration of flora and fauna. Scientists predict that if society does not change the directions of socio-economic development, technological methods of mastering nature, then the beginning of irreversible destruction of the biosphere is predicted in the near future. Purpose. Ensuring the economic growth of the country at present is accompanied by the growth of environmental pollution and degradation, depletion of natural resources, disruption of the balance of the biosphere, climate change, which leads to the deterioration of human health and limits the possibilities of further development This means that the level of well-being of the population is tight related to ensuring the quality of the environment. The development of industrial society gave rise to new needs, and the need to satisfy them required a new increase in production, the consequences of such development became a heavy yoke for the environment. Along with the growth of labor productivity and the improvement of the efficiency of the economic activity of enterprises, today the question is their willingness to apply advanced technologies capable of reducing the negative impact on the environment and more rationally using natural resources, increasing the level of waste processing and mastering zero-waste technologies. Conclusions. This testifies to the relevance of the conducted research, the purpose of which was analytical work on the interrelationship of environmental and economic factors of the development of society with the position of the unity of these processes. The solution to the given task was performed on the basis of the interrelationship of resource and environmental factors. It is stated that one of the components of the modern development of the economy is the substantiation of the economic and scientific relationship to environmental safety. A possible association is economic activity with indicators of the economic state and the nature of the impact on it.

Effects of Grinding Methods and Water-to-Binder Ratio on the Properties of Cement Mortars Blended with Biomass Ash and Ceramic Powder.

To combat environmental challenges-such as the depletion of natural resources and a high carbon footprint-and contribute to the effort of achieving zero-waste technology and sustainable development, the use of agricultural and industrial wastes in the cement industry has created a research interest. This study explores the potential of two types of harvest residue ash (HRA) and three types of ceramic waste (CP) as supplementary cementitious materials (SCMs) through: (1) the characterization of raw materials and (2) examining the physical properties and mechanical performance of cement-based mortar samples prepared with 10%, 30% and 50%wt of the selected SCMs ground into powder form as cement replacement. Two main variables were the water-to-binder ratio (w/b) and the effect of different grinding procedures. Experimental results demonstrated that flexural and compressive strengths were not significantly impaired by SCM additions of up to 50%, but higher replacement levels led to an increased permeability and higher capillary water absorption due to the dilution effect. Also, a lower w/b was shown to effectively reduce the porosity of mortar and increase its mechanical properties, allowing for higher shares of SCMs to be utilized. This study verifies the technical feasibility of cob corn ash and ceramic powder application as SCMs in mortar formulations, further promoting the practice of incorporating industrial and agricultural by-products in greener cementitious composites.

Regeneration of sodium bicarbonate from industrial Na-based desulfurization waste using ammonium hydroxide

In an effort to improve industrial waste recycling and realize zero-waste technology, we optimized the regeneration of sodium bicarbonate from desulfurization waste using aqueous ammonia. Sodium bicarbonate is essential for absorbing SO2 gas in flue gas desulfurization. Based on X-ray fluorescence analysis, desulfurization waste consists of 86.2% sodium sulfate. Rapid deposition of undesired ammonium bicarbonate in a reactor was observed at the early stages of the reaction when using ammonia gas, resulting in insufficient yield. For further improvement, the effect of ammonia solution dosage was explored in detail. The yield/purity of sodium bicarbonate regenerated from desulfurization waste is very close to that from pure sodium sulfate, 58.2/85.9% and 56.6/91.5%, respectively. Moreover, owing to greater surface area, the as-regenerated sample showed higher desulfurization performance (97% removal rate) than commercial sodium bicarbonate (88.6%) on 200 ppm SO2 gas at a 5 g/min feeding rate.

Recovery of phosphates from anaerobic MBR effluent using columns of eggshell and seagrass residues and their final use as a fertilizer

The combination of a submerged anaerobic membrane bioreactor (SAnMBR) and two biowaste adsorption columns (eggshell (EGSL) and seagrass (SG)) was studied for the first time to evaluate the recovery of phosphates from wastewater. Reject wastewater from anaerobic sludge dewatering process was fed into the SAnMBR and the results showed a COD removal of 50%. The phosphate removal efficiency was low and as such, the effluent from SAnMBR was then passed through two columns containing thermally treated eggshell and seagrass residues for further phosphate removal. The final effluent analysis confirmed that phosphates could be additionally removed resulting in over 95% recovery (flow rate 0.3 L d−1), for both biowaste materials. The ammonium and COD removal after the adsorption columns was low, indicating the high selectivity towards phosphates. Moreover, the solid residues after adsorption were evaluated as soil conditioners on Lepidium sativum and Sinapis alba seeds. The SG end product exhibited high GI values for both seeds tested indicating a positive effect on plant growth, while the EGSL end product negatively affected the seed germination. The fractionation analysis of phosphorus showed that inorganically bound phosphorus (IP) was the major phosphorus fraction in EGSL and SG end product, accounting for 92.6 and 95.7% of TP, respectively. The results of this study suggest that the SG and EGSL could be effectively reclaimed as selective adsorbents towards phosphates in combination with a SAnMBR and the SG solid residues after adsorption can be directly applied for agricultural purposes, contributing to the development of a zero-waste technology.

Receiving triacetin from sunflower oil

One of the promising types of vegetable raw materials in Ukraine, which can be used for the development of resource-saving technologies, are vegetable oils. The products of their processing serve as raw materials for obtaining surface-active substances, which are used in the production of food additives, pharmaceutical products, detergents and cosmetics, biofuels and additives. The most common oil in Ukraine is sunflower, which, like other vegetable oils, can be processed to form fatty acids and their salts. The initial process of vegetable oil processing is hydrolysis. The technological parameters of the sunflower oil hydrolysis process under different conditions were studied. It was investigated that the alkaline hydrolysis of sunflower oil in the presence of sodium hydroxide proceeds the fastest in comparison with thermal methods in the presence of sulfuric acid and superheated steam, the conversion of raw materials reaches 100 % in the 25th minute of the experiment, at a process temperature of 60 °C. The waste in this process is a glycerol solution, which can be used to obtain its esters for the purpose of implementing a zero-waste technology scheme. A method of using sunflower oil hydrolysis waste is proposed, which consists in its esterification with acetic acid, as a result of which triacetin is formed – a valuable product for use in many sectors of the national economy. In the food industry, triacetin is known as a food additive under the code E1518, which is used as a humectant and stabilizer to preserve freshness, as a plasticizer and binder thickener, as a solvent and odor fixer. Due to its ability to be broken down into its components – glycerol and acetic acid and absorbed without any side effects in the human body, triacetin is safe for use. It was investigated that the esterification reaction between the waste product of the hydrolysis of vegetable oil – a solution of glycerin in water and acetic acid took place at a conversion of raw materials of 100 %, while the selectivity of the target product remained constant at the level of 80 %. At the same time, the concentration of the glycerol solution did not affect either the amount of conversion or the value of selectivity. As a catalyst in this process, p-toluenesulfonic acid was used in a relatively small amount – 1.0 % by volume, so it did not significantly affect the composition of the reaction products, and this, in the future, makes it possible to conduct the process without additional purification from traces of the catalyst.

Utilization of coffee husk ash for soil stabilization: A systematic review

Coffee is currently one of the most prized food commodities. Its production has grown so much in recent times, however, the waste by-products generated are also huge. It is envisioned that with rapid urbanization and construction, the use of these by-products can offset the demand for construction materials such as cement and concrete. It is now generally accepted that the manufacture of cement and concrete reduces the supply of natural aggregates at the same time generates carbon dioxide emissions and deteriorates the environment. In this paper, the sustainable use of coffee husk ash (CHA), produced from coffee production is discussed. The CHA necessitates huge land for storage and is normally then left in site locations where it is first dumped, while others are burned in incinerators, contributing to air pollution, thus creating a significant environmental issue. This article will first focus on general coffee production, consumption, and waste by-products. Its life cycle from plantation to wastes is then discussed followed by the effective usage of CHA for the production of ceramics and use in soil stabilization. The article summarizes the use of CHA in soil stabilization and examines development patterns in terms of strength and durability. The findings indicate that adding CHA into soil stabilization benefits both sustainability and zero-waste technologies.

Recycling of isabgol (Plantago ovata Forsk.) straw biomass and mineral powder with bio-inoculants as an effective soil amendment for isabgol cultivation

Efficient utilization of isabgol ( Plantgo ovata Forsk.) straw biomass through preparation of bio-active organic fertilizer in a natural composting process has not been studied. In this study, phosphate rock and silicate mineral (mica) powder were used as natural sources of phosphorus (P) and potassium (K), respectively. Cow dung slurry as a natural decomposer was mixed with the straw biomass at a 10:1 (weight/weight) ratio along with mineral powder. Then, nutrient-mobilizing bio-inoculants were used in the composting process after attaining thermal stabilization. The agronomic effectiveness of the resulting bio-active compost (BAC) as a bio-organic fertilizer was compared with that of conventional organics (farmyard manure and vermicompost) and chemical fertilizer (CF) by growing isabgol under field conditions. Composting with the natural sources of P and K along with the bio-inoculants increased the total nitrogen (13.6 g kg -1 ), P (38.7 g kg -1 ), and K (31.2 g kg -1 ) contents in the final product ( i.e ., BAC) compared with composting without the mineral powder and bio-inoculants. Application of BAC remarkably improved the seed yield (2.5%) and husk quality of isabgol in comparison with conventional organics and CF. Compared with CF, BAC significantly boosted the economic yield of isabgol by improving the husk recovery (2.5%) and mucilage yield (4.12%). Furthermore, BAC significantly improved the soil quality by increasing organic carbon (C), available nutrients, and microbial biomass C contents, as well as enzyme activity. The positive correlation between soil and plant parameters also highlighted the benefits of BAC for isabgol production through soil quality improvement. Therefore, it can be considered as a zero-waste technology, whereby a large quantity of straw biomass generated from isabgol cultivation, which contains essential nutrients, can be recycled back to the soil. Furthermore, BAC can be effectively used as a bio-active organic fertilizer, particularly in systems where chemical inputs are restricted, such as organic agriculture.

Cyprinus carpio Skeleton Byproduct as a Source of Collagen for Gelatin Preparation.

Byproducts obtained from fish processing account for up to 70% of their live weight and represent a large amount of unused raw materials rich in proteins, fats, minerals, and vitamins. Recently, the management of the use of predominantly cold-water fish byproducts has become a priority for many processing companies. This paper describes the biotechnological processing of byproducts of warm-water Cyprinus carpio skeletons into gelatins. A Taguchi experimental design with two process factors (HCl concentration during demineralization of the starting material and the amount of enzyme during enzyme conditioning of the collagen) examined at three levels (0.5, 1.0 and 2.0 wt%; 0.0, 0.1 and 0.2 wt% respectively) was used to optimize the processing of fish tissue into gelatin. Depending on the preparation conditions, four gelatin fractions were prepared by multi-stage extraction from the starting material with a total yield of 18.7–55.7%. Extensive characterization of the gel-forming and surface properties of the prepared gelatins was performed. Gelatins belong to the group of zero–low-medium Bloom value (0–170 Bloom) and low–medium viscosity (1.1–4.9 mPa·s) gelatins and are suitable for some food, pharmaceutical, and cosmetic applications. During processing, the pigment can be isolated; the remaining solid product can then be used in agriculture, and H3PO4Ca can be precipitated from the liquid byproduct after demineralization. The carp byproduct processing technology is environmentally friendly and meets the requirements of zero-waste technology.

Improvement of geotechnical properties of clayey soil with saw dust ash stabilization

Rapid urbanization and construction are driving up the consumption of cement and aggregate used in building construction. However, the manufacture of cement and concrete boosts carbon dioxide emissions and depletes the supply of natural aggregates. As a result, alternative materials for building construction are required. A replacement material, saw dust ash (SDA), is obtained from woodfired power stations, pulp, paper mills, and other wood-burning factories. However, the SDA manufacturing sector necessitates enormous tracts of land in rural locations. As a result, some wood waste is sprinkled throughout the open land, while others are burned in incinerators, contributing to air pollution, a significant environmental issue. The purpose of this study is to provide a brief overview of the practical usage of SDA as a substitute material in the building sector, especially for soil stabilization. The article provides an overview of SDA use in the construction sector and examines development trends such as strength and durability. The findings indicate that implementing SDA into soi the soil stabilization sector benefits both sustainability and zero-waste technology. Environmental concerns about using SDA are also discussed, as are methods for minimizing the dangerous influence on the surrounding environment for future disaster risk reduction due to soil failure.