| 1. |
- Abadi, Imam, et al.
(author)
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Design of Adaptive Neuro-Fuzzy Inference Control Based One-Axis Solar Tracker on Battery Charging System
- 2020
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In: E3S Web of Conferences. - : EDP Sciences. - 2267-1242. ; , s. 1-15
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Conference paper (peer-reviewed)abstract
- The photovoltaic (PV) panel can produce electrical energy that is very environmentally friendly and easy to use. The use of PV panels is suitable for supplying peak loads or at night using batteries as energy storage. However, the battery needs to manage for control, and the battery can last long. The solution to battery management problems is through research about the battery charging system. The DC-DC converter used is the Single Ended Primary Inductance Converter (SEPIC) type. Voltage Control of the battery charging using Adaptive Neuro-Fuzzy Inference System (ANFIS). In the simulation of bright conditions, ANFIS controls can track the charging point set point and obtain a voltage response with a rise time of 0.0028 s, a maximum overshoot of 0.027 %, a peak time of 0.008 s, and a settling time of 0.0193 s. When charging a solar tracker, PV battery gets a 0.25 % increase compared to a fixed PV panel. PV solar tracker can follow the direction of the sun's position. The irradiation value and maximum temperature affect the input voltage and input current that enters the converter.
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| 2. |
- Abadi, Imam, et al.
(author)
-
Performance Study of Maximum Power Point Tracking (MPPT) Based on Type-2 Fuzzy Logic Controller on Active Dual Axis Solar Tracker
- 2020
-
In: E3S Web of Conferences. - : EDP Sciences. - 2267-1242. ; , s. 1-16
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Conference paper (peer-reviewed)abstract
- World energy consumption increases with time, so that occur an energy imbalance. Many breakthroughs have developed to utilize renewable energy. The photovoltaic system is one of the easy-to-use renewable energies. The power conversion from PV fixed is still low, so the PV system is designed using the active dual-axis solar tracker. The PV tracker position can be adjusted to change the sun position to get maximum efficiency. The active dual-axis solar tracker system is integrated with the maximum power point tracking (MPPT) algorithm to keep PV operating at a maximum power point even though input variations change. The active dual-axis solar tracker system integrated with the maximum power point tracking (MPPT) algorithm to keep PV operating at a maximum power point even though input variations change. Tracking test simulation had done by comparing the output power of a fixed PV system with the active dual-axis solar tracker. Type-2 fuzzy logic based MPPT successfully increased the average output power by 10.48 % with the highest increase of 17.48 % obtained at 15:00 West Indonesia Time (GMT+7). The difference in power from a fixed PV system with the active dual-axis solar tracker of 36.08 W is from the output power worth 206.3 to 242.4 W.
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| 3. |
- Burlakovs, Juris, 1977-, et al.
(author)
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Environmental Quality of Groundwater in Contaminated Areas—Challenges in Eastern Baltic Region
- 2020
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In: Water Resources Quality and Management in Baltic Sea Countries. - Switzerland : Springer. - 9783030397005 - 9783030397012 ; , s. 59-84
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Book chapter (peer-reviewed)abstract
- The lack of water in the future will force society to find more sophisticated solutions for treatment and improvement of groundwater wherever it comes from. Contamination of soil and groundwater is a legacy of modern society, prevention of contaminants spread and secondary water reuse options shall be considered. The aim of the book chapter is to give oversight view on problems and challenges linked to groundwater quality in Eastern Baltic region whilst through case studies explaining the practical problems with groundwater monitoring, remediation and overall environmental quality analysis. The reader will get introduced with case studies in industry levels as credibility of scientific fundamentals is higher when practical solutions are shown. Eastern Baltic countries experience cover contamination problems that are mainly of historic origin due to former Soviet military and industrial policy implementation through decades. Short summaries for each case study are given and main conclusions provided in form of recommendations at the very end of the chapter.
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| 4. |
- Burlakovs, Juris, 1977-, et al.
(author)
-
Fluorescence Spectroscopy – Applied Tool for Organic Matter Analysis
- 2019
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In: <em>Goldschmidt Abstracts</em>, 2019.
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Conference paper (peer-reviewed)abstract
- Large applied projects in various sub-fields of environmental science studied and analyzed properties of organic matter. The “Life-Sure” is as continuation of started work for cost effective bottom sediments treatment where organic matter play important role of sorption of urban contaminants; “CONTRA” - beach wrack studies for advanced value-based bioeconomy development. Another project on Jurassic clay is interesting in discourse on Pleistocene glaciers glaciodynamics. Material from field was tested by 3D fluorescence excitation-emission matrix (EEM) providing “fingerprints” for a single compound or a mixture of fluorescent components. Thus humic macromolecules might be well seen nevertheless structural units have variable effects on the wavelength as well as intensity of fluorescence. It decreases with increasing molecular size of the humic macromolecule. For applied environmental projects this is well non-destructive tool to quantify the decomposition degree of organic matter requiring negligible amount of sample. This important method is valid for both organic matter and humic substances analytics. Chemical nature of humic substances can be correlated to structural information, e.g., functional groups, poly-condensation, aromaticity, dynamic properties related to intermolecular interactions. Acquired data from EEM provided significant input for scientific knowledge and innovation along with other analytical tools.
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| 5. |
- Burlakovs, Juris, 1977-, et al.
(author)
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Gateway of Landfilled Plastic Waste Towards Circular Economy in Europe
- 2019
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In: Separations. - : MDPI. - 2297-8739. ; 6:2, s. 1-8
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Journal article (peer-reviewed)abstract
- For decades, significant work has been conducted regarding plastic waste by dealing with rejected materials in waste masses through their accumulation, sorting and recycling. Important political and technical challenges are involved, especially with respect to landfilled waste. Plastic is popular and, notwithstanding decrease policies, it will remain a material widely used in most economic sectors. However, questions of plastic waste recycling in the contemporary world cannot be solved without knowing the material, which can be achieved by careful sampling, analysis and quantification. Plastic is heterogeneous, but usually all plastic waste is jointly handled for recycling and incineration. Separation before processing waste through the analytical approach must be applied. Modern landfill mining and site clean-up projects in contemporary waste management systems require comprehensive material studies ranging from the macro-characterization of waste masses to a more detailed analysis of hazardous constituents and properties from an energy calorific standpoint-where, among other methods, thermogravimetric research coupled with life cycle assessment (LCA) and economic assessment is highly welcomed.
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| 6. |
- Burlakovs, Juris, 1977-, et al.
(author)
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Geophysical aspects of abandoned landfill geomorphological and material properties macro-characterization
- 2020
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In: International Multidisciplinary Scientific GeoConference Surveying Geology and Mining Ecology Management, SGEM. - : International Multidisciplinary Scientific Geoconference. - 9786197603057 ; , s. 551-558
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Conference paper (peer-reviewed)abstract
- Landfills (dumps) are places where the end of the life cycle of products can be found - useful material is dumped away from the sight creating contaminant flows around. Another problem is huge unexplored potential of resources recycling - we have limited knowledge also on useful elements and materials that are buried. The solution to overcome the limitations that provide remote sensing and traditional geodesy, proximal sensing techniques could be used. “Near surface geophysics” with operation at or just below the soil surface, significantly may contribute to give answers that traditionally are solved only after excavation. Geophysical methods are various, those can be active (i.e. create its own signal) or passive (i.e. register an existing signal); invasive (by inserting devices into the soil) or non-destructive. Some of these methods are static (e.g. a sequence of inserted electrodes), others can be used in a mobile way (e.g. pulled by a quad-bike). In general, their depth of exploration can vary from a few decimetres to some tens of metres. Thus in range of wide geophysical methodology spectrum almost all methods might be of use for unknown dump exploration depending on circumstances. In this paper, the aim is to macro-characterize anthropogenic geomorphological forms for contouring of old buried dumps by use of magnetometry, and geoelectric research methods to provide knowledge on approximate content of the dump. Protonmagnetometer was used in Eastern Latvia to determine unseen on surface dumpsite, buried in forest; induced polarisation and electric resistivity research was done in Southern Sweden for the macro-content analysis of dump hills composed of glass industry residuals and construction waste mixture. Geophysical surveying was performed to support site investigation with respect to landfill-related environmental problems, to enhance the opportunity for contouring of location of material mass and initially evaluate its physical properties. Results have shown good potential of geophysical surveying to spatially characterize landfill masses (location and dimensions) and to identify the internal structure of a landfill site, which already provides valuable information to estimate the landfill mining (material recovery) potential of landfills.
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| 7. |
- Burlakovs, Juris, 1977-, et al.
(author)
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Ground-penetrating Radar (GPR) Geoenvironmental Screening in Lakes of Latvia - Challenges and Outcomes
- 2016
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Conference paper (peer-reviewed)abstract
- Geophysical studies in mapping and geoenvironmental applications for screening purposes are widely applied in Latvia. Ground-penetrating radar (GPR) as the one method from geophysical toolbox is a non-invasive and non-destructive way where pulsed electromagnetic signal is recorded as scattering from subsurface objects. Aim of two described screening studies was to analyse potential advantages of GPR use for mapping bottom sediments and topography in two lakes and pinpoint challenges to overcome during works. Both lakes are relatively deep and of sub-glacial origin that became lakes after the ice retreat from Baltic region. Characterization of bottom sediments as well as full core description of upper limnic layers for comparison with GPR signals were performed. Major results show that GPR, coring and laboratory analysis can be used simultaneously, however, ground penetration radar sometimes fails to recognize full picture needed for geoenvironmental application needs. Proper treatment of data nevertheless diminish the necessity of dense coring in lakes when budgets are strict.
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| 8. |
- Burlakovs, Juris, 1977-, et al.
(author)
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Implementation of new concepts in waste management in tourist metropolitan areas
- 2020
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In: 2019 9TH INTERNATIONAL CONFERENCE ON ENVIRONMENT SCIENCE AND ENGINEERING (ICESE 2019). - : IOP Publishing. ; , s. 1-10
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Conference paper (peer-reviewed)abstract
- The urban waste in tourist cities needs comprehensive global research efforts and proceeded action as for metropolitan areas huge impact and load on waste management is generated. Waste management and resource conservation strategies are prepared in state-of-the-art level however implementation and future improvement of the current situation is crucial. Some examples in waste prevention and management for better tourism, waste and resource management are provided in the paper as outcomes from Horizon2020 project "Urban Strategies for Waste Management in Tourist Cities". The policy and tools based on information gathered by scientists, municipal and NGOs experience (e.g. separation of bio-waste in catering industries, "sin-wastes" as from the bars, nightclubs and smoker places, reuse of unnecessary items that can serve for others and many more) are described. In addition, regulatory instruments (e.g. ban of plastic bags, reduction of allowed bio-waste in landfilling), economic instruments (taxes) and voluntary agreements (e.g. deposit systems; cleaning actions by volunteers) might be used to implement and elaborate the situation within environmental management and prevention practices in tourist metropolitan cities. Food waste prevention, beach and littoral management, special practices for festival waste and large amount specific waste generating facilities (e.g., entertainment industry, cruises etc.) are of high importance. The future outlook may be concentrated on digitalizing of waste flows and using the "big data" concept for better and smarter waste management.
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| 9. |
- Burlakovs, Juris, 1977-, et al.
(author)
-
Metals and rare Earth’s elements in landfills : case studies
- 2016
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In: 3rd Int. Symposium on Enhanced Landfill Mining, Lisboa, 8-10/2/2016.
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Conference paper (peer-reviewed)abstract
- Landfills are considered as places where the life cycle of products ends and materialshave been “disposed forever”. The landfill mining (LFM) approach can deal with formerdumpsites and this material may become important for circular economy perspectiveswithin the concept “Beyond the zero waste”. Potential material recovery should includeperspectives of recycling of critical industrial metals where rare Earth elements (REEs)are playing more and more important role. Real-time applied LFM projects in the BalticRegion have shown the potential of fine-grained fractions (including clay and colloidalmatter) of excavated waste as storage of considerably large amounts of valuable metalsand REEs. Analytical screening studies have extended a bit further the understanding offine fraction contents of excavated, separated and screened waste in a circular economyperspective. The Swedish Institute and Latvian Research Program “Res Prod” supportedthe research.
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| 10. |
- Burlakovs, Juris, 1977-, et al.
(author)
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On the way to 'zero waste' management : Recovery potential of elements, including rare earth elements, from fine fraction of waste
- 2018
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In: Journal of Cleaner Production. - : Elsevier. - 0959-6526 .- 1879-1786. ; 186, s. 81-90
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Journal article (peer-reviewed)abstract
- Existing schemes of solid waste handling have been improved implementing advanced systems for recovery and reuse of various materials. Nowadays, the 'zero waste' concept is becoming more topical through the reduction of disposed waste. Recovery of metals, nutrients and other materials that can be returned to the material cycles still remain as a challenge for future. Landfill mining (LFM) is one of the approaches that can deal with former dumpsites, and derived materials may become important for circular economy within the concept 'beyond the zero waste'. Perspectives of material recovery can include recycling of critical industrial metals, including rare earth elements (REEs). The LFM projects performed in the Baltic Region along with a conventional source separation of iron-scrap, plastics etc. have shown that the potential of fine-grained fractions (including clay and colloidal matter) of excavated waste have considerably large amounts of potentially valuable metals and distinct REEs. In this paper analytical screening studies are discussed extending the understanding of element content in fine fraction of waste derived from excavated, separated and screened waste in a perspective of circular economy. Technological feasibility was evaluated by using modified sequential extraction technique where easy extractable amount of metals can be estimated. Results revealed that considerable concentrations of Mn (418-823 mg/kg), Ni (41-84 mg/kg), Co (10.7-19.3 mg/kg) and Cd (1.0-3.0 mg/kg) were detected in fine fraction (<10 mm) of waste sampled from Hogbytorp landfill, while Cr (49-518 mg/kg) and Pb (30-264 mg/kg) were found in fine fraction (<10 mm) of waste from Torma landfill revealing wide heterogeneity of tested samples. Waste should become a utilizable resource closing the loop of anthropogenic material cycle as the hidden potential of valuable materials in dumps is considerable.
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