Technological and Environmental Evaluation of Incinerator Systems for Sustainable Waste-to-Energy Solutions in Denpasar City

Waste disposal, energy production and pollution minimisation are key problems that must be addressed for sustainable cities of the future. In a world with finite resources witnessing a population explosion, much effort is being made to change the way in which developed societies consume energy and materials and dispose of waste. This paper reviews the current UK practices of segregation and treatment of municipal solid waste (MSW) with focus on advanced thermal treatment technologies. MSW is segregated either at source or at dedicated facilities across the country. The residues of waste segregation can be thermally treated for energy recovery. Direct incineration of unsorted waste is currently the main route practiced by the energy from waste (EfW) industry. Typical MSW incinerators can burn wastes with a wide range of calorific values without any waste pre-processing. However, these incineration systems have low energy efficiency and suffer from unfavourable public opinion. Consequently, gas clean-up technologies associated with waste incinerators have been developed further, especially for dioxin removal and fly ash treatment. The two main alternatives to incineration are gasification of pre-processed waste and production of solid recovered fuel (SRF) from mechanical and biological treatment (MBT). Both processes have potentially higher energy efficiencies than incineration and more flexibility in the use of primary products. Further technology developments with regulatory drivers are required to compete with incineration. Another route available for EfW is pyrolysis, producing cheap and storable fuel products. Pyrolysis is suitable only for specific types of waste material. Pyrolysis of waste wood can produce a good-quality char that can be readily burned in coal-fired power plants or other higher energy efficiency thermal systems.

Organic waste upsurges with rapid urbanization and incessant population growth. To restrain this trend and lessen environmental impacts, sustainable management of food waste imposes an ambitious target of resource recovery and mitigating greenhouse gas emissions. This study quantifies environmental impacts and socio-economic benefits of municipal solid waste (MSW) management as a proof-of-concept case study for the Lima, Peru. Economic feasibility and life cycle assessment studies were used to compare the efficiency of segregated organic waste for scenarios such as landfilling and composting. Resource recovery, GHG emissions, and revenues are assessed to decide the environmental contour and downstream strategies. It was found that composting has less environmental impact in 11 out of 12 life cycle impact categories (ReCiPe method) during collection, processing, and distribution of 1 ton of waste as functional unit. Composting resulted in 40% less climate impact with global warming potential (GWP) of 476.20 kg CO2eq whereas landfilling showed 785.81 kg CO2eq GWP. Additionally, organic waste to compost conversion rate of 13%, can bring positive upshots to economy and society. This study is instrumental in MSW management, decision-making, and mitigate climate change in line with United Nations Sustainable Development Goals (UN-SDGs) for sustainable society.

A cost effective alternative to the existing treatment steps of the refining by-ptoducts, is the “on site” energetical valorization through 2 comparable technologies: thermal oxidation and anaerobic digestion combined with boiler. In a thermal multifluid oxidizer Cinclus® , the mixture is injected with atomisation and combustion air at high velocity into the oxidation chamber. The jet creates a local under-pressure and thus an internal recirculation in the oxidation chamber. This results in a controlled and homogeneous temperature and residence profile that ensure an optimal combustion with low emissions. To prevent persistent boiler fouling, the gases are cooled to below 750 °C in the gas conditioning chamber by mixing the hot gases with recycled gases taken from behind the de-dusting device. Divert investment for fossil fuel boiler and soap stock splitting to install Cinclus soap stock boiler will allow: no acid waste water, no interphase, no sulfuric acid consumption, no fossil fuel consumption. The Dranco process is a well-known and reliable anaerobic digestion technology. Its simple digester design, no moving parts within the digester, provides a high reliability and low maintenance costs. The Dranco process parameters are roughly: digester loading: 10 to 20 kg COD/m3 reactor.day. The temperature range of the thermophilic organisms is 50 to 58 °C. The retention time in the digester is about 15 to 30 days. The biogas production is above 300 m3 of biogas per ton of waste. The electricity production: above 500 kWh per ton of waste. The advantages of anaerobic digestion of waste are: The production of renewable energy and reduction of fossil CO2 -emissions ; the low odour emissions and in general low emissions towards the environment.

This manuscript proposes an integrated system for treating hospital solid waste (H.S.W.) consisting of an incineration and frictional sterilization system capable of operating during normal and emergency situations. We analyzed the benefits of integrating different hospital solid waste (H.S.W.) treatment systems with the existing stand-alone incineration system, with a particular emphasis on the thermal friction sterilization integration system. The objective was to define the economic advantages and benefits in terms of resources recovery of using the thermal frictional sterilization–incineration integrated system during the hospital’s normal and emergency/pandemic operating conditions. We modeled three modeling scenarios based on normal and emergency operating conditions. The results show that the H.S.W. was composed of 74% general H.S.W. Existing incineration systems would be the most expensive process because the sanitary transportation cost represented approximately 96% of the H.S.W. costs. The hospital would realize 40–61% savings relative to the existing method if the integrated incineration–frictional systems were implemented to treat 50–70% of H.S.W.; the savings were better than in other scenarios. Proposed scenario 3 had a much better resources recovery factor than scenarios 1 and 2. This modeling study showed that a thermal frictional sterilization–incineration system could work well even under emergency conditions if the H.S.W. in-house sorting/transportation/storage process is modified to cater to other H.S.W. treatment/sterilization systems.

With around 10 tonnes of waste being generated for every man, woman and child each year across the globe, safe disposal of it all has become an urgent environmental problem. In 1993, Western Europe, the United States, Canada, Japan, Australia and New Zealand produced a total of 480 million tonnes of industrial waste and 8 billion tonnes from activities such as energy production, agriculture, mining and sewage disposal. The emission to the atmosphere of both heavy metals and acid gases and perhaps more important in the longer term, the Dioxins/Furans (PCDDs/PCDFs), promises to be one of the key issues facing not only the industry but the society as a whole over the next decade and more. Although it is increasingly likely that measures to control toxic emissions will have to be directed at a wider target than just the waste incinerators, it is equally certain that both public opinion and legislation will, at least in the first instance, see the incinerators as one of the most obvious candidates for tighter regulation. These days, virtually all the new research and development techniques in combustion technology involve the application of computational fluid dynamics (CFD) to combustor design. This seems to be the best approach to solving design problems. Mathematical modelling thus is seen as an inherent part of practically all combustion research programmes. The new discipline of computational fluid dynamics can also be used to help minimise flame generated pollutants released to the atmosphere. These pollutants include; CO2, CO, SO2, NOx, HCl, Hydrocarbons, soot, particulates, heavy metals and dioxins/furans. CFD studies of their release to the atmosphere must include not only their source in the flame, but also their removal from the flue gases by scrubbing and other techniques. The governing differential equations for the process being studied must be defined and solved simultaneously if the parameters in the equations are interacting. At present, this procedure can give valuable insight into the effect of design parameters on the flow field and concentrations of major species. In the case of many pollutants, the equations governing their production does not affect the flow field or concentrations of major species. Thus the equations are effectively decoupled and the pollutant formation, convection and diffusion can be calculated in a post-processor. This paper presents and discusses the results of our CFD modelling work at two large municipal and a newly commissioned 5 MW clinical incinerator plants in UK.

The growing population in urban areas generates large volumes of hospital waste which intensifies the problem of hospital waste management in developing countries. This study is designed to evaluate environmental impacts associated with hospital waste management scenarios using life cycle assessment (LCA) approach. Two scenarios were designed to describe the current practices: (scenario A) and an integrated approach (scenario B), which includes segregation and recycling of hospital waste. Data were collected from five public hospitals located in the district of Sheikhupura, Pakistan. The collected hospital waste was quantified and categorized on a daily basis for five consecutive months (October 2020 to February 2021). The functional unit was defined as one tonne of hospital waste. System boundaries for two scenarios include segregation, transportation, treatment and disposal of hospital waste. After defining functional unit and system boundaries, LCA was conducted using the IGES-GHG simulator. The scenarios were evaluated using common parameter, i.e., greenhouse gas (GHG) emissions. Scenario A and scenario B resulted in net GHG emissions of 1078.40 kg CO2-eq. per tonne of waste and 989.31 kg CO2-eq. per tonne of waste, respectively. Applying an integrated approach, it would be possible to mitigate GHG emissions of 37,756.44 kg CO2-eq. per tonne of waste annually and to recover some materials such as glass, paper, plastic and metals. Therefore, implementing an integrated approach for the management of hospital waste will progress the entire system towards sustainability. The findings of this study can be used for future research and policymaking.

As industrialization accelerates and the amount of hazardous waste generated gradually increases, the means of disposal of hazardous waste is of increasing concern. In this paper, a 40 t/d counter-flow rotary kiln incineration system owned by a Jiangsu environmental protection company was researched. The software Aspen Plus was used to build the mixed pyrolysis model and the software Fluent was used to build the computational fluid dynamics model of the incineration system. The influence of the calorific value of the hazardous waste, the operating temperature and the air supply on the operational effectiveness of the incineration system were analyzed by varying the simulation conditions. The results show that the SOx and NOx content of the product is lower when the operating temperature is above 800 °C. The incineration system could only operate above 800 °C when the calorific value of the hazardous waste is not less than 1500 kcal/kg. The incineration system operated best at a primary air velocity of 1.5 m/s. The simulation results in this paper serve as a guide for the operation of counter-flow rotary kiln incineration systems.

In order to improve the combustion characteristics of municipal waste materials and reduce excess pollutants generated during the incineration process, this study develops a novel waste incinerator with an α-shaped flue gas route. This has been achieved through the application of momentum vector synthesis theory in order to modify the secondary air structure in a conventional incinerator, resulting in enhanced combustion efficiency of the incinerator. Computational Fluid Dynamics (CFD) based cold state test results demonstrate that with appropriate modifications to the design of the incinerator, the flue gas propagates through a longer α-shaped route rather than conventional L-shaped route. Hot state tests have been carried out on a full scale 750 tons/day waste incinerator. Test rests show that the temperature of the flue gas increases by 138% under the front arch when secondary air supply is being incorporated into the design of the incinerator, resulting in better combustion of the municipal waste materials, lower emissions and higher thermal efficiency of the incinerator. The results obtained in this study confirm the rationality and feasibility of momentum flow rate method for better design of waste incinerators.Graphical

Waste management is a pressing issue in urban areas, including Denpasar City, which produces over 1,000 tons of waste daily. Limited infrastructure, low public participation, and weak institutional coordination have created inefficiencies in the current system. This policy paper proposes strategies to strengthen waste management institutions at the sub-district level to improve service effectiveness. Through secondary data analysis, regulatory review, and assessment of policy alternatives, the study finds that the absence of Waste Management Technical Implementation Units (UPTD) in sub-districts significantly hinders service delivery and community involvement. Of four policy options considered, establishing UPTDs simultaneously in all sub-districts is identified as the most effective and sustainable. This approach is expected to improve operational responsiveness, encourage local innovation, and support national waste management goals. Strengthening territorial-level institutions is therefore essential to developing a decentralized and sustainable waste management system in Denpasar City.

Reducing Disposable Surgical Items: Decreasing Environmental Impact and Costs at a Children's Hospital, a Pilot Study

Incinerator and cement kiln capacity for hazardous waste treatment

The energy industry has a major impact on the sustainability level of global economies, from job creation to resource efficiency and environmental impact. The aim of our study was to examine the phenomenon of energy production and its main determinants in 37 European economies during the period of 2011–2021. The methodological approach entailed the use of the panel first-difference generalized method of moments (GMM). The empirical results show that the relationship between energy production and predictors such as imports, energy prices, energy productivity, and energy efficiency was monotonic. At the same time, our results indicate a relationship between energy supply and energy production, imports, productivity, and prices. Moreover, energy production depends significantly on the energy productivity, primary energy consumption, and energy imports.

Municipality Solid Waste Management (MSWM) is an absolute challenge for the nation because it affects the resources and the economy adversely. The rapid growth of urbanization has many adverse impacts on waste management, making it one of the major problems of the developing nations. Research studies indicate that 90% of municipality solid waste finds its ways into open dumps, with severe health hazards and environmental degradations. The Pirana landfill in Ahmedabad is one such example receiving approximately 4,000 metric tonnes of waste daily. One of the major reasons for poor management of waste is the lack of environmental awareness, irresponsible civic behaviour and inadequate education. Hence it si most necessary to impart environmental education, especially at school levels to bridge the gap in habits, attitudes, and behaviour towards waste-disposal practices. Against this background, the paper emphasizes waste management education delivered at Gujarat Secondary and Higher Secondary Education Board (GSEB) schools in Ahmedabad. A set of primary data from 24 schools were collected by making use of structured questionnaires filled by school teachers. The findings suggest that although schools adopt several methods of teaching imparting positive attitudes and practices regarding waste disposal among students is still a big issue. The study further discusses the waste disposal practices at school level and found that 61.5% schools rely on municipal services to dispose of waste generated within their premises. It also concludes and calls for increasing the strength of environmental education, upgrading the hands-on training of teachers, and implementing changes to the curriculum to mitigate these issues effectively.

Denpasar City, a popular tourist destination, is struggling to maintain peace and order due to rapid urbanization and an influx of migrants. This has led to an increasing number of job seekers exceeding the job opportunities available in the city. The problems in writing this thesis are (1) How is the implementation of the control of vagrants and beggars by the Pamong Praja Police Unit in Denpasar City? and (2) How are the obstacles faced by the Pamong Praja Police Unit in controlling vagrants and beggars in Denpasar City. The research method used is an empirical method by collecting data through interviews with related parties, document analysis, and direct observation of the curbing process. The results showed that the curbing and handling of vagrants and beggars in Denpasar City has not gone well, seen from the many activities of vagrants and beggars in Denpasar City so that it still disturbs public order. The obstacles of the Civil Service Police Unit in controlling vagrants and beggars are divided into Juridical and Non-Juridical obstacles. The Denpasar City Government is still trying to deal with the social problems of vagrants and beggars by means of preventive, refrensive, and rehabilitation.

Clinical laboratories play a vital role in healthcare but are also among the most resource-intensive hospital units. High energy and water consumption, extensive use of single-use plastics, and the generation of non-recyclable biomedical waste present major environmental challenges. This study aimed to quantify the environmental and economic burden associated with common and avoidable practices in clinical laboratory medicine, including: excessive blood collection, inappropriate test ordering, and unnecessary tube duplication in pre-analytical workflows. Real-world data from the Clinical Biochemistry Laboratory of the AOU Maggiore della Carità (Novara, Italy) for the year 2024 were analysed to quantify the environmental and economic impact of inappropriate test ordering based on minimum retesting intervals, as well as pre-analytical practices, including redundant sample tube collection and excessive blood volumes relative to analytical requirements. Inappropriate retesting of selected biomarkers resulted in 2,931 unnecessary tubes, generating over 26.7 kg of avoidable waste. Redundant EDTA tubes for complete blood count, glycated haemoglobin, erythrocyte sedimentation rate, and haemoglobin electrophoresis led to 356.14 kg of excess waste, which could be eliminated through sample consolidation. In haematology, 264,834 CBC tests generated 2.62 tonnes of biological waste. For biochemistry, 3 million tests produced 36.98 tonnes ofwaste. Excessive blood collection and unnecessary test repetition contribute to significant but avoidable environmental and financial burdens. Pre-analytical interventions, such as reducing tube volume and consolidating tests, could prevent over 40 tonnes of waste and save more than € 60,800 annually in a single laboratory.