Waste Disposal Costs Research Articles

Measures to reduce negative effects of waste using the Amu-Bukhara machine channel

The work discusses the state of use of the Amu-Bukhara canal. It also considers the number and size of suspended watercourses that affect existing hydraulic structures. The large amount of suspended runoff creates problems such as turbidity of the canal during operation, overflow of front runoff. Solving the problem through modern technologies and innovative proposals is a requirement of today. The application of the proposed collection mechanism can reduce labor costs for waste disposal by 30–35% and operating costs by 45%. In addition, proposals and recommendations were given to improve the existing suspension treatment facilities.

High cost of waste treatment calls for systematic rethinking: A case study for a chemical industrial park in China

AbstractThe chemical industry has witnessed a heavy global environmental clean‐up and remediation burden. Chemical industrial parks (CIPs) are important carriers of the chemical industry and present both opportunities and challenges in terms of environmental sustainability. The end‐of‐pipe waste treatment system, comprised of enterprise facilities and shareable infrastructure, is mandatory in Chinese CIPs; in that sense, its cost is often taken for granted without accurate calculation, and reduction opportunities are commonly missed. Quantifying the whole‐process cost is thus crucial for promoting the waste treatment system of CIPs. This study established a bottom‐up and trilayer nested model for waste treatment, which integrated interphase material flows, pollutant reduction technology, and whole‐process cost accounting by targeting CIPs. The cost included wastewater treatment, waste gas treatment, and solid waste disposal costs, and each component further included depreciation, operation, and other expenditures. After empirically applying the model to a typical CIP in China, we revealed that this CIP attained a total waste treatment cost of 1.31 billion CNY (0.19 billion US dollars) in 2016, which is approximately 52.4% of the park's tax income. Overall, approximately 55.6% of the cost was attributable to wastewater treatment (729 million CNY, 108 million US dollars), 12.5% to waste gas treatment, and 31.9% to solid waste disposal. In the empirical case study, the cost imposed a substantial economic burden on the industrial park, while the environmental performance of the waste treatment system still required improvement. The results called for systematic rethinking which is featured by an extended system boundary and three dialectical relations in CIPs. Three policy recommendations were proposed by systematic rethinking, including symbiotic solutions targeting waste treatment infrastructures within and among enterprises, priority optimization on the key enterprises with high pollution emissionsand treatment costs, and flexible deployment of in‐plant waste treatment facilities.

Efficient Strategies For Managing Food Waste In Institutional Catering: A Comprehensive Study

Background: Food waste is a pressing global issue, and its management within institutional catering facilities is of paramount importance. Institutions such as College, hospitals, and corporate cafeterias generate substantial amounts of food waste, contributing to environmental concerns and economic inefficiencies. This abstract presents a comprehensive study aimed at identifying efficient strategies for handling food waste in institutional catering settings. Objectives: The primary objectives of this study were to Investigate the multifaceted impact of food waste management strategies in institutional catering and propose practical recommendations to enhance food waste management in these settings. Methodology: To achieve these objectives, a quantative -methods approach specifically descriptive research design was employed. Data was collected through online questionnaire through google form from few students who had explored few sets of institutional catering facilities. convenience sampling method was used for the data collection. Sample size was 194.Data were analysed using software spss 23 on the basis of Likert scale-based questionnaire. Results: The results of the one-sample tests indicate a significant difference (p < 0.001) in food waste generation between institutions implementing various food waste reduction strategies, with a mean difference of 2.98 (95% CI: 2.786 to 3.183). Additionally, there's a significant difference (p < 0.001) in the cost of food waste disposal between institutions employing waste reduction practices and those that do not, with a mean difference of 3.06 (95% CI: 2.868 to 3.256). The adoption of various approaches to cut down on food waste in institutional catering has shown a clear impact on the quantity of food waste generated. This discovery underscores the considerable potential of these strategies in decreasing the volume of food waste generated. Conclusion: Institutional catering can significantly reduce food waste through strategic implementation of waste reduction practices, menu planning, staff training, technology utilization, and customer engagement, resulting in cost savings, environmental benefits, and enhanced compliance and satisfaction.

Recovering the Soybean Hulls after Peroxidase Extraction and Their Application as Adsorbent for Metal Ions and Dyes

This study is aimed at extending the soybean hulls’ lifetime by their utilization as an adsorbent for metal ions (Cd2+ and Cu2+) and dyes (Reactive Yellow 39 (RY 39) and Acid Blue 225 (AB 225)). ATR-FTIR spectroscopy, FE-SEM microscopy, and zeta potential measurements were used for adsorbent characterization. The effect of the solution’s pH, peroxidase extraction, adsorbent particle size, contact time, the pollutant’s initial concentration, and temperature on the soybean hulls’ adsorption potential was studied. Before peroxidase extraction, soybean hulls were capable of removing 72% Cd2+, 71% Cu2+ (at a pH of 5.00) or 81% RY 39, and 73% AB 225 (at a pH of 3.00). For further experiments, soybean hulls without peroxidase were used for several reasons: (1) due to their observed higher metal ion removal, (2) in order to reduce the waste disposal cost after the peroxidase (usually used for wastewater decolorization) extraction, and (3) since the soybean hulls without peroxidase possessed significantly lower secondary pollution than those with peroxidase. Cd2+ and Cu2+ removal was slightly increased when the smaller adsorbent fraction (710-1000 μm) was used, while the adsorbent particle size did not have an impact on dye removal. After 30 min of contact time, 92% and 88% of RY 39 and AB 225 were removed, respectively, while after the same contact time, 80% and 69% of Cd2+ and Cu2+ were removed, respectively. Adsorption of all tested pollutants follows a pseudo-second-order reaction through the fast adsorption, intraparticle diffusion, and final equilibrium stage. The maximal adsorption capacities determined by the Langmuir model were 21.10, 20.54, 16.54, and 17.23 mg/g for Cd2+, Cu2+, RY 39, and AB 225, respectively. Calculated thermodynamic parameters suggested that the adsorption of all pollutants is spontaneous and of endothermic character. Moreover, different binary mixtures were prepared, and the competitive adsorptions revealed that the soybean hulls are the most efficient adsorbent for the mixture of AB 225 and Cu2+. The findings of this study contribute to the soybean hulls’ recovery after the peroxidase extraction and bring them into the circular economy concept.

Analysis of industrial symbiosis case studies and its potential in Saudi Arabia

Industrial symbiosis (IS) involves sharing waste, by-products, heat, and logistics streams. Participating entities are benefitted by reducing resource utilization and waste disposal cost, improving reuse, and creating job opportunities. Hence, countries have used it to ensure clean and sustainable economic growth. The Kingdom of Saudi Arabia (KSA) has initiated a few IS-related approaches that focus mainly on the power sector. However, the role of IS in Saudi industries is still limited, and there is significant potential for the enhancement of the major sectors, including oil and gas, petrochemicals, iron and steel, power generation, desalination, cement, and paper and pulp industries. This study investigated 11 successful IS cases and proposed a symbiotic exchange framework. A roadmap for IS implementation is also developed by considering the enablers and the barriers and by outlining the framework, initial steps, and policy levels. However, to deploy IS activities in KSA, technological, economic, and regulatory obstacles must be overcome and the enablers should be enhanced to conserve resources, reduce environmental impacts, and improve social well-being. The future studies should focus on unique challenges of the Kingdom including availability of energy resources at low price, dependency on fossil-fuels, dispersed development, limited availability of water resources, and limited R&D focus on IS.

Effectiveness of mixing poultry litter compost with rice husk biochar in mitigating ammonia volatilization and carbon dioxide emission

Nitrogen-rich materials such as poultry litter (PL) contributes to substantial N and C loss in the form of ammonia (NH3) and carbon dioxide (CO2) during composting. Biochar can act as a sorbent of ammonia (NH3) and CO2 emission released during co-composting. Thus, co-composting poultry litter with rice husk biochar as a bulking agent is a good technique to mitigate NH3 volatilization and CO2 emission. A study was conducted to evaluate the effects of composting the mixtures of poultry litter with rice husk biochar at different ratios on NH3 and CO2 emissions. Four mixtures of poultry litter and rice husk biochar at different rate were composted at 0:1, 0.5:1, 1.3:1 and 2.3:1 ratio of rice husk biochar (RHB): poultry litter (PL) on a dry weight basis to achieve a suitable C/N ratio of 15, 20, 25, and 30, respectively. The results show that composting poultry litter with rice husk biochar can accelerate the breakdown of organic matter, thereby shortening the thermophilic phase compared to composting using poultry litter alone. There was a significant reduction in the cumulative NH3 emissions, which accounted for 78.38%, 94.60%, and 97.30%, for each C/N ratio of 20, 25, and 30. The total nitrogen (TN) retained relative was 75.96%, 85.61%, 90.24%, and 87.89% for each C/N ratio of 15, 20, 25, and 30 at the completion of composting. Total carbon dioxide lost was 5.64%, 6.62%, 8.91%, and 14.54%, for each C/N ratio of 15, 20, 21, and 30. In addition, the total carbon (TC) retained were 66.60%, 72.56%, 77.39%, and 85.29% for 15, 20, 25, and 30 C/N ratios and shows significant difference as compared with the initial reading of TC of the compost mixtures. In conclusion, mixing and composting rice husk biochar in poultry litter with C/N ratio of 25 helps in reducing the NH3 volatilization and CO2 emissions, while reducing the overall operational costs of waste disposal by shortening the composting time alongside nitrogen conservation and carbon sequestration. In formulating the compost mixture with rice husk biochar, the contribution of C and N from the biochar can be neglected in the determination of C/N ratio to predict the rate of mineralization in the compost because biochar has characteristic of being quite inert and recalcitrant in nature.

Economic and environmental analysis of plastics pyrolysis after secondary sortation of mixed plastic waste

Plastic usage has quickly grown in recent years as plastics have become an essential material in everyday life. Unfortunately, recycling rates have not matched the increased growth, with the majority of waste plastic currently landfilled in the United States. New chemical recycling technologies, i.e. pyrolysis, are needed to increase the recycling rates of waste plastics. However, pyrolysis is challenged with bridging of feed into the hot reactor and in the high cost of waste plastic feedstock. In this work a novel liquid-fed pyrolysis process, designed to eliminate bridging, was modeled through process simulation and assessed over a range of processing conditions. A secondary sortation of inexpensive mixed plastic waste from material recovery facilities provided a low-cost feedstock (PE, PP) for pyrolysis. A techno-economic analysis and life cycle assessment found favorable economic and environmental results for pyrolysis oil when compared to fossil naphtha ($561/t, 0.52 kg CO2 eq./kg). A sensitivity analysis found the economic results most responsive to waste plastics feedstock costs, pyrolysis gas sales, operating capacity, and waste disposal costs. Furthermore, it is recommended to recover and sell sorted PET from the mixed plastic bale and implement heat integration in pyrolysis, which in our study achieved lower minimum selling price and greenhouse gas emissions for pyrolysis oil then for fossil naphtha.

Improving the Utilization of Food Waste: Conversion of Food Waste into Residual Food Dried Substance and Use of This Material as a Culture Nutrient for Microbial Production of Lactic Acid.

To reduce food waste (FW) disposal costs, many Koreans now convert FW into residual food dried substances (RFDS) using a house-service food drying machine and then dispose of the RFDS. To recycle RFDS, we tested whether RFDS could be used as a culture nutrient to produce value-added microbial chemicals. As a case study, we attempted to produce lactic acid (LA) by cultivating lactic acid bacteria using RFDS. To prepare the culture medium for LA production, we finely ground the RFDS and dissolved it with CaCO3, a pH-controlling agent. Six lactic acid bacteria were tested to improve LA production, with Lactococcus lactis showing the highest LA production. To enhance LA production, three hydrolytic enzymes, amylase, protease, and lipase, were introduced separately or simultaneously into the RFDS medium during the cultivation of the L. lactis strain. The addition of amylase alone was the most effective in increasing LA production. We then investigated the effect of the RFDS concentration on LA production. The highest LA production was achieved when 100g/L of RFDS was used. LA production was scaled up using a 5L bioreactor. During the fermentation, LA production improved to 46.32g/L, which was 1.73-fold higher than that (26.83g/L) obtained from the flask culture. These results show that RFDS from FW can be used as a culture nutrient to produce LA. Our study provides a new and simple FW recycling method and lays the foundation for expanding the usability of FW.

Theatre sustainability: our journey to reach net zero

Background: In 2021, University College London Hospitals declared a climate and health emergency and committed to reach net zero CO2 emissions by 2031. Our theatre sustainability team has so far focused on (a) reducing our use of inhalation agents, (b) improving our waste streaming, and (c) education. Here we summarise some of our projects. Methods: (a) In February 2021, desflurane was removed from our anaesthetic machines after departmental consensus. Our department purchased 138 TIVA pumps so that availability of pumps was not a barrier to using TIVA. (b) We introduced tiger-stripe bags to dispose of our non-infectious clinical waste. Previously only orange bags were being used for clinical waste in theatre, which have a higher cost and carbon footprint than tiger-stripe bags.1 We surveyed staff on waste management then introduced tiger-stripe bags to one theatre during a pilot week. We carried out daily staff education and weighed all the bin bags. (c) Education initiatives to increase awareness and engagement of staff and patients include audit day presentations, updates at theatre multidisciplinary teaching, a sustainability journal club, and an ongoing patient and staff survey on environmental sustainability and healthcare. Results: (a) There has been a downtrend in use of desflurane to almost zero (Fig. 15). There has been an overall upward trend in use of TIVA (as shown by number of 50- and 100-ml propofol vials used) and downwards trend in sevoflurane use (Fig. 15). A survey conducted in November 2021 showed 50% of those surveyed used TIVA for more than 75% of general anaesthetics. There has also been a downward trend in total volume of nitrous oxide used. (b) The use of tiger-stripe bags during the pilot week resulted in a 32% reduction in waste disposal cost and 59% reduction in CO2 emissions. Tiger-stripe bags have now been introduced to all 27 elective theatres across three separate sites. Conclusions: With appropriate education, engagement, and provision of the required equipment, we have reduced our use of inhalation agents (desflurane in particular), increased our use of TIVA, and made significant carbon and cost savings through optimising our waste streaming. We are now working on reducing our use of single-use items, minimising energy wastage and conducting life cycle assessments of common operations. 1.Rizan C, Bhutta MF, Reed M, Lilywhite R. J Clean Prod 2021; 286: 125446

Plant biomass as potential economic commodities for agricultural purposes.

The world’s population is growing continually and is projected to reach nine billion by the year 2050. This growth rate requires increased and economically viable food production and an adequate supply of quality water to sustain life. Increased food production and supply of water require adding fertilizers and possible recycling of wastewater, to address the improvement of soils’ nutritional status and potable water shortages, respectively. The objectives of this work were to determine the nutrients in sewage-impacted wastewater, borehole water, agricultural waste, and commercial fertilizer (control) materials, and their heavy metal content was also carried out to determine their suitability for use. In addition, Moringa seed pods and Morula nutshells were investigated as a bioremedial approach for the removal of toxic metals from aqueous samples. An attempt to regenerate sorbent was made since the saturated sorbents that contain the metal ions are not safe for disposal as they can pollute the environment. Nutrients were analyzed by HPLC, while metals were analyzed using a Varian 220FS Atomic Absorption Spectrometer operated with air/acetylene. Nonedible agricultural materials were found to contain appreciable amounts of plant nutrients such as nitrates (NO3 -), nitrites (NO2 -), and phosphates (PO4 3-) as well as metal ions such as magnesium, copper, and zinc, which are beneficial for plant growth. Results obtained from analysis of sewage water effluent showed that heavy metal and nutrient concentrations decreased in the treatment stage. The utilization of Moringa oleifera seed pods for metal removal from wastewater is viable and would reduce costs for waste disposal and can offer alternatives to conventional methods for the removal of unwanted or toxic species from the environment. It showed potential for removing selected metal ions such as Pb, Cd, Cu, Fe, and Zn from polluted water. This organically treated wastewater is environmentally friendly and may be used for applications which do not require potable water, such as irrigating golf courses, lawns, and crops, or for industrial purposes, if proper measures are taken to ensure its quality.

Bio-Based Circular Economy and Polygeneration in Microalgal Production from Food Wastes: A Concise Review

The production of biofuels from microalgae has gained considerable attention due to the rapid diminution of fossil fuels. Despite major advantages, microalgal biofuels deployment still faces obstacles associated with the cost of biomass production and waste disposal. The production could become more cost-effective and feasible if the wastes in the production processes are recycled/reused and the biofuels produced are co-produced with high-value co-products. The aim of this review is to discuss and analyze the importance of recycling/reusing wastes and co-producing high-value products to be implemented with biofuels from microalgal-based processes. Recent advances in circular economy/integration and polygeneration, as proper strategies, are discussed. Circular economy and integration entail the reuse of food wastes, waste biomass, and wastewater in microalgal conversion processes for producing biofuels. The main focus of the section of this review on circular economy is food waste reuse for microalgal production. Polygeneration is the production of multiple products, including a biofuel as the main product and multiple co-products to ensure process cost reduction. The results reported in relevant studies have shown that microalgal growth and metabolite accumulation could be favored by mixotrophic cultivation using wastes from the conversion processes or reused food wastes. The co-production of high-value products, including pharmaceuticals, proteins, carbohydrates, pigments, bioplastics, pellets, and biofertilizers may also favor the sustainability of biofuel production from microalgae.

Recycling of phosphate tailings and acid wastewater from phosphorus chemical industrial chain to prepare a high value-added magnesium oxysulfate cement

Phosphate tailings (PT) and acid water, by-products of phosphorus chemical industrial chain, are usually identified as waste because they can hardly be reused in cement production. This paper proposes an approach of recycling solid waste PT and acid wastewater in preparing a high value-added magnesium oxysulfate (MOS) cement. Results show that the phosphorus in acid water promotes the formation of 5 Mg(OH)2·MgSO4·7H2O (517) phase, thereby improving compressive strength of MOS cement. MOS cement prepared with undiluted acid water present excellent resistance to water and acid. The incorporation of calcined PT lowers the strength of MOS cement but improves the volume stability. The phosphorus and fluorine in acid water are effectively immobilized by the cement matrix. Moreover, recycling of PT and acid water to produce MOS cement not only largely consumes the waste and benefits the environment, but also reduces the cost of waste disposal and cement production.

Assessing Durability Properties and Economic Potential of Shellfish Aquaculture Waste in the Construction Industry: A Circular Economy Perspective

The construction industry’s high demand for natural resources, combined with the waste generated by agriculture, creates an opportunity for the circular economy. This experiment used the CaCO3 found in scallop shells as an ingredient for the manufacture of fire-resistant materials, replacing gypsum in compositions of 40% and 50% by weight. The mechanical compressive strength was estimated for both freeze-thaw cycles and acid and sulfate attacks. The cost of disposing of scallop shell waste in landfills, savings from substitution, and the payback period relative to the amount of production were determined. The compressive strength of the materials decreased by 80% when subjected to freeze-thaw cycles and sulfate attack. In response to acid attack, they showed a 100% increase in strength during the first three weeks and a decrease thereafter. The savings amounted to $46.36 (22.4%) for 40% replacement and $58.93 (28.4%) for 50%. Respectively, return on investment is achieved at 800- and 630-per-metric ton produced. The difference between the costs of waste disposal (in aquaculture) and the potential savings from using CaCO3 as a raw material (in construction) creates an opportunity for commercialization between the two industries, serves as a reference for decision-makers, and complies with circular economy principles, reducing both inputs of raw materials and outputs of waste.

Disposable and reusable instruments in dental health practice: A comparison of cost factors in a public provider organization in Queensland, Australia.

Choosing between reusable instruments (RIs) and disposable instruments (DIs) for dental care provision requires a careful consideration of costs and their contributing factors, alongside other choice criteria. This study aimed to assess the current use of instruments in the West Moreton Oral Health Service (WMOHS) in Queensland, Australia, with a broader goal of informing future practice in this and comparable organizations. A cost model was developed reflecting costs arising from procurement, reprocessing and disposal, depending on the RI and DI composition of instrumentation. The current practice in WMOHS was compared to modular (RI-only and DI-only) strategies by considering four standard instrument sets (examination, simple extraction, surgical extraction, restoration) and the annual use of instruments in the organization at large. The use of resources (water, electricity) and emissions (waste) were quantified for each strategy. The robustness of findings was explored across a range of scenarios that involved varying instrument prices, lifespans, factors impacting on the cost of reprocessing (labour, water, energy), the cost of waste disposal and couriering. At the organization level, the current mix of instruments (A$1.28 m per year) was 4% more costly than the lower cost, RI-only alternative (A$1.23 m). However, with lower DI prices or higher labour costs current practice would become the lowest cost option. Results for specific instrument sets varied by service type. DI-only offered the lowest cost option for oral examinations (A$6.29), and the current practice of mixed instrumentation for simple extractions (A$16.56). RI-only sets were less costly in more resource intensive procedures such as surgical extractions (A$40.19) and restorations (A$43.83). In terms of environmental impacts, the use of instruments based on current practice required 37% of water and energy use of an RI-only alternative and generated 36% waste of the DI-only alternative. Reusable instruments are generally less costly than DIs, but for specific instrument sets the outcome depends on the type of procedure. In some circumstances, mixed instrumentation can provide the lowest cost alternative. While the WMOHS instrument mix used in current practice does not minimize cost for the provider, it may be justified in light of operational risks, logistics and uncertainty regarding cost factors.

Analyzing the state and protection of environment in the Nizhny Novgorod Oblast

Subject. Environmental pollution affects the living standards of the population, the economic situation of the region, its investment attractiveness, thus determining the need to assess the ecological situation and environmental costs. Objectives. The study aims to provide a quantitative assessment of air pollution, contamination of water basins, soil, condition of waste disposal, forest health, and current costs and investments in fixed assets for environmental protection. It also reviews the content of regional environmental projects of the Nizhny Novgorod Odlast and their financial support. Methods. The study draws on generalization of official statistical information, materials of federal and regional executive authorities, and employs methods of structural, dynamic, trend, and comparative analysis. Results. I reviewed the state of atmospheric air, soil, water and forest resources, industrial and household waste disposal, identified sources of nature pollution, estimated the costs of environmental protection, unveiled prospects for improving the quality of environment within the framework of environmental projects in the Nizhny Novgorod Oblast. Conclusions. The pollution of atmospheric air and soil is quite low in the region, however, only 40% of pollutants emitted into the atmosphere are neutralized, half of the wastewater is polluted. The most important problem is solid and liquid waste management. Investments in fixed capital are more than twice as high as the current costs of environmental protection, significant investments in the improvement of the Volga and rivers of the Volga basin are envisaged within the framework of regional projects "Ecology".

MAIN DIRECTIONS OF RESEARCH ON THE USE OF TES ASH IN THE PRODUCTION OF BUILDING MATERIALS

Formulation of the problem. The basis of modern energy − various types of power plants, of which thermal power plants is about 40 %. The technology of electricity production at thermal power plants is harmful due to the generation of large amounts of waste. They account for more than 30 % of emissions of harmful substances from the total emissions of industrial enterprises. Increased demand for electricity causes an increase in their production, which leads to an increase in the amount of ash and slag waste and emissions of harmful substances into the atmosphere. The purpose of the article . In Ukraine, 160 thousand hectares out of 60 million hectares of total area are dumps of industrial waste, or as they are called by-products. About 8 million tons of ash and slag waste are generated in Ukraine every year, and their storage is accompanied by a number of extremely negative consequences for the environment and human health. With ash and slag dumps containing toxic elements polluting the ground water and underwater, require exclusion of large areas. The volume of already accumulated waste reaches more than 300 million tons and occupies huge areas of land. At the same time, almost all ash and slag dumps of Ukrainian coal-fired and thermal power plants are almost full, so more and more areas are needed to continue the work. Analysis of recent research and publications. According to European researchers, this type of waste disposal costs about 60 euros/ton. The average thermal power plant spends about 12…36 million euros a year just for the maintenance of ash dumps.

Preparation of activated carbon from sewage sludge using green activator and its performance on dye wastewater treatment

ABSTRACT The remediation of dyes in wastewater using activated carbon produced from sewage sludge pyrolysis char (PYC) is an environmentally friendly and sustainable process. However, traditional activators can cause corrosion of the processing facility, thereby increasing the costs of waste disposal. Here, activated carbons were prepared from sewage sludge PYC, and the effects of activation conditions (different activators, temperature and time, and char:activator mass ratio) on their specific surface areas and adsorption of iodine and methylene blue (MB; model dye) were studied. The results showed that a value of 952 m2/g could be attained for the specific surface area and values of 882 and 162 mg/g for the adsorption of iodine and MB, respectively, by heating PYC with KHCO3 (PYC- KHCO3: 1:2 w/w) for 60 min at 800 ℃. Compared with activation by KOH, the adsorption of MB using PYC-KHCO3 was slightly lower but the yield was 13.7% higher. Optimization of the activation process using surface response modelling indicated that sensitivity of three key factors to the adsorption of iodine and MB followed the order: Mass ratio > temperature > time. Systematic investigation of the effects of time, pH and temperature on the removal of MB by the activated carbon revealed that adsorption conformed to the Langmuir model and pseudo-second-order kinetics. The proposed mechanisms of MB adsorption involved ion exchange, functional group complexation and physical/π-π interactions. This study provides a basis for the efficient remediation of dyes in wastewater using activated carbon prepared from sustainable sewage sludge PYC and green chemistry.

Policies for Material Circularity: the Case of Lithium

Improper waste management carries social risks and dissipates high-value materials. Moreover, material market prices do not reflect these hidden costs and values. Two important questions are how prices can inform society about their resource use impact and how market-based policies optimize material circularity. This study adds to the literature by analyzing the effect of market-based policies aimed at promoting circular material reuse in a market defied by harmful waste but enhanced by recycling. The findings indicate that a landfill tax is a first-best policy since it targets the external costs of waste disposal, improves welfare, reduces damages, and boosts recycling. If a landfill tax is not feasible, other programs like taxes, subsidies, and a tax-subsidy scheme provide second-best results. Remarkably, recycling subsidies can stimulate higher raw material extraction and generate rebound effects. We also explore other non-market-based strategies to prevent waste and make recycling more cost-competitive and easier to recycle. The numerical results and sensitivity analysis of the lithium market illustrate the model's flexibility and prove why some policies are superior to others for reducing waste and creating value from used materials. Our study results serve as a guide to designing policies for optimal material circularity.

Planning and Risk Analysis in Projects of Procurement of Agricultural Raw Materials for the Production of Environmentally Friendly Fuel

The purpose of the research is to substantiate the method of planning the need for technical equipment of corn waste collection projects for the production of environmentally friendly fuel, which is based on simulation of work taking into account the changing design environment. During the research, the methods of simulation modeling of corn waste collection projects for the production of environmentally friendly fuel were used. The methods of probability theory and mathematical statistics were used, which provided the substantiation of models of natural-climatic and production conditions of corn waste collection projects for the production of environmentally friendly fuel. As a result of the conducted research the method and statistical simulation model of planning the need for technical equipment of projects on collecting the waste of corn for production of environmentally friendly fuel has been developed. They provided an assessment of the timely implementation of work in selected fields, taking into account the changing design environment, which leads to the risk of the specific cost of corn waste disposal. A simulated model for the collection of maize waste available for disposal, provided that the balance of organic carbon in the fields is maintained, and tested for adequacy according to the Mann-Whitney test. Based on the use of the developed simulation model, the indicators of the use of technical equipment and the trend of changing the risk of the specific cost of disposal of corn waste are substantiated. Rational scenarios for the implementation of projects for which there are no risks for a given project environment are identified.

Bioconversion of plant wastes into feed and nutritional yeast preparations

The lack of protein in the diet of humans and animals, the presence of a large amount of plant waste, which have further potential for use, but are now almost not used, are serious problems that require immediate solutions. Modern methods of biotechnology are able to solve this issue. The purpose of this review was to study the existing technologies for using yeast to produce protein from plant waste. Waste of plant biomass, which are initially indigestible polysaccharides, when using special processing methods, break down into easily fermentable sugars, which can serve as a good substrate for the accumulation of full-fledged yeast protein, and the yeast cell wall is able to bind toxins, undesirable microorganisms and remove them from the intestinal tract of humans and animals, allowing them to be included in the composition of biologically active additives for functional purposes. The review examines the advantages of using yeast in comparison with other microorganisms and the technology of the process. It is possible to use deep and solid-phase cultivation, the first of which is technologically preferable. The products and preparations produced by foreign and domestic manufacturers are considered. Yeast is used for feed preparations:Candida, Saccharomyces, Hansenula, Torulopsis, Rhodotorula, etc.; for the food industry – mainlySaccharomices cerevisiae, Torula. The resulting products, enriched with protein and components of yeast cells, differ significantly from analogues in nutritional value. This approach to the use of industrial waste at enterprises can make many production cycles closed, increase the environmental friendliness of plants, reduce unnecessary waste disposal costs and increase total revenue.