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Phosphoric sludge is the most harmful and dangerous of waste of phosphorus-containing substances, and its aggregated volumes, by rough estimates, total millions of tons. Therefore utilization of the that waste is now an acute problem and will bring rather notable contribution not only to national economies, but will also considerably improve ecological conditions (Bessarabov et al., 2010a). Development of industrial productions for processing of phosphoric sludge was carried out within the most modern and prospective system of computer support - CALS-technologies (Continuous Acquisition and Life Cycle Support). The task of the CALS is transformation of product life cycle to highly automated process by re-structuring of business processes included into it (Saaksvuori, Immonen, 2010). In development of advanced chemical productions it is shown that CALS-technologies and the main CALS-standard, ISO 10303 STEP, offer of a solution of a problem of electronic representation of the design information by means of use of the standardized integrated description of a product. The designer’s electronic description according to standard ISO 10303 STEP contains structure of categories, documents, statuses, groups of products with their versions, properties, classifications, etc (Molina et al., 1999). Marketing researches of the phosphoric industry waste utilization (Bessarabov et al., 2010b), system researches of innovative resources of leading enterprises making and utilizing phosphorus-containing production wastes (Bessarabov et al., 2010c) were carried out within the grant of European Community ECOPHOS ? INCO-CT-2005-013359, and also the flexible two-product scheme of phosphoric sludge utilization with obtaining of sodium phosphite and hypophosphite (Bessarabov et al., 2009, Klemeš et al., 2006) was developed. In the given work carried out under the contract of Ministry of Education and Science of Russia no. 11.519.11.5005, we considered the complex of three individual productions flowsheets of phosphoric sludge utilization, including sodium phosphite and hypophosphite, and also phosphoric sludge processing through sodium phosphite to dibasic lead phosphite.

The purpose of this study is to better provide optimal control schemes and management services for heating enterprises. To this end, a cloud computing-based integrated heating network management and control system was introduced in this paper. Based on cloud computing service, a platform for integrated management and control was established. Besides, the combined control scheme of equipment management and control was proposed, and research on its technical issues was conducted. The results show that this scheme has significant adaptability. Thus, it can be used in the internal system of heating enterprises in the future.

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Lignocellulosic biomasses are gaining attention for biofuel production to supplement the increasing energy demands. This study is focused on identifying the candidacy of pinewood for hydrogen production through subcritical (300°C), near-critical (370°C) and supercritical (550°C) water gasification. Pinewood was gasified to study the impacts of temperature (300-550°C), feed concentration (20-30 wt%) and reaction time (20-60 min). The effects of metal catalysts (e.g., Ni/Al2O3, Ru/Al2O3, NaOH and KOH) were also examined to maximize hydrogen yields and carbon gasification efficiency. The individual gas yields, total gas yields and lower heating values were calculated for comparative evaluation between subcritical, near-critical and supercritical water gasification as well as between catalytic and non-catalytic gasification of pinewood. Supercritical water gasification at higher temperatures (550°C), longer reaction time (60 min) and lower feed concentration (20 wt%) improved water-gas shift reaction resulting in high hydrogen yields. Greater yields of hydrogen (0.52mmol/g) and total gases (6.4 mmol/g) with lower heating value of 423 kJ/Nm3 was found with 20 wt% ofpinewood at 550°C and 60 min. Ni/Al2O3 at a concentration of 5 wt% showed highest yields for hydrogen (2.54 mmol/g) in the gas products when compared to other catalysts. The catalytic activity towards hydrogen production decreased as Ni/Al2O3 > KOH > Ru/Al2O3 > NaOH. The findings imply that pinewood is a promising feedstock for hydrogen production by supercritical water gasification.

Due to the potential ability to support local development, create local employment, and contribute to climate change mitigation decentralized bioenergy CHP systems are receiving increasing attention. With bioenergy CHP systems are possible to achieve energy efficiency by converting primary energy to heat and electricity, replacing fossil fuels and reducing carbon dioxide emissions in the atmosphere. In particular, biomass cogeneration is considered a reliable efficient energy production technology and an effective alternative to reduce greenhouse gas emissions due to their low CO2 emission, using near biomass production sites (e.g., agricultural activities, forestes), avoiding long supply chains. In this paper, a techno-environmental assessment for a biomass powered micro-scale CHP system based on gasifier combined with an internal combustion engine sized for a maximum electrical and thermal output of 20 kWe and 40 kWth, is analyzed. CO2 direct emissions and CO2 equivalent emissions for NO2, CO, HC were assessed in order to obtain the final environmental impact of the plant. Several cases were considered changing biomass kind and flue gas treatment systems. Results show that biomass kind has not an impact on the toxic gas emissions, while the bioscrubber is the best flue gas treatment technology to reduce concentrations of all pollutants.

Torrefaction kinetics of Norwegian biomass fuels, including spruce (softwood) and birch (hardwood) was studied using a thermogravimetric analyser. Small samples of approximately 10 mg and particle size of 63-125 µm were heated at a constant heating rate of 5 °C/min and kept afterwards for 4 hours in isothermal conditions at different temperatures (230, 240, 250, 260, 270 and 280 °C). A two-step kinetic model was employed to simulate the recorded mass loss curves. The results showed that thedecomposition of the initial biomass in the first step, to form an intermediate solid and volatiles, exhibited a higher conversion rate compared with the second step.

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New alternatives for alcohol production from low-cost feedstocks, such as lignocellulosic biomasses, have been proposed. Banana wastes are an example of these substrates. Existing applications involve the use of the fruit, leaves and other residues, such as the pseudostem. Centrifugation is commonly used for the separation of the solids in the fermentation broth. However, due to the presence of banana residues in the broth, it is necessary to evaluate whether the solid-liquid separation method interferes with the composition of the clarified broth (wine) that is sent to ethanol recovery by distillation. Based on this scenario, the objective of this study was the characterization of the liquid and solid phases for three separation methods: centrifugation, vacuum filtration and microfiltration. Centrifugation was performed at 3800 rpm.min-1 for 20 min and vacuum filtration was conducted with the fermentation broth poured through a filter paper in a Buchner funnel. Microfiltration was performed using a capillary membrane module (polyimide) at room temperature with a flow rate of 90 L.h-1. The loss of ethanol in the liquid phase was evaluated for each method; no differences among the methods were observed. Few differences in the clarified broth composition were verified after centrifugation compared with vacuum filtration and microfiltration. For the removal of solids, microfiltration resulted in a minor presence of total solids in the liquid. These results support microfiltration as a potential method for the separation of solids and liquids in fermentation broth from banana waste. Similarly, the moisture content, Chemical Oxygen Demand (COD), Total Nitrogen (TN) and pH were determined for the solid phase that was discarded after the separation. The highest COD and moisture contents and the lowest value of TN were obtained with microfiltration. The solid residue should be characterized with respect to other constituents and properties to assess their use in processes such as biogas production.

For further development and infrastructure planning, considerations regarding economically feasible, efficient and appropriate waste management are essential. In current waste management networks and related datasets, errors and discrepancies arise in the reported values, to due to an insufficient detail of used infrastructure, which is often reduced to only several nodes in the case of very complex tasks. This paper presents an optimised multi-criteria mathematical programming model, which enables to obtain data for more detailed infrastructure while preserving the efficiency of the calculation using mathematical modifications and algorithms. The paper describes the method of how to divide the estimated flows in a chosen area among different sources. The optimized robust model minimizes the total sum of absolute deviations from the original data. It also considers logistics in the form of distances and emulates the economic behaviour of subjects in the network. The alternating direction method of multipliers is applied for an original model solution, together with a heuristic used for one set of ambiguous variables. This algorithm facilitates the solving of large instances of the defined problem. The implementation of the algorithm and all computations are done in the Julia programming language involving specialized optimisation libraries. The functionality of the optimised model is shown on the sewage sludge management network dataset of the Czech Republic, which contains approximately 200 entities. Such a dataset leads to the model with approximately 400,000 of decision variables. The results of the presented case study are used for the improvement of the treatment of sludge, a waste produced in wastewater treatment plants. The proposed model is general enough as it can be also used for estimating real waste flow datasets containing a similar type of error as described.