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Related to energy requirements for non-cellulose i. e. polyester production as an energy-intensive process, potential saving options are proposed. From the process data, it is evident that unit operations need electric and thermal energy in significant amounts. At the same time, improved energy management could be realized by applying a combined heat and power system (CHP) instead of the usually used process with separate heat and power production. In addition, the boiler flue gases with a sufficiently high outlet temperature could be used for combustion air preheating.Considering industrial process data, a calculation and comparison between the primary energy demand for conventional, CHP system and flue-gas heat recovery is presented. Comparison between separate heat and electricity production i.e. the conventional system with an overall efficiency of 55.6 % and CHP with efficiency of 85 %, shows an absolute efficiency increase of 29.4 %. Using an air preheater for combustion air temperature increasing saves 5.6 % of the fuel and at the same time diminishes thermal pollution because the exhaust flue-gas temperature becomes 77.3 °C instead of 204 °C. Conclusively, cogeneration and flue-gas heat recovery presentsfuel savings, which also implies economic and environmental benefits.

Biodiesel is the first alternative fuel which physico-chemical properties are regulated by appropriate standards: American ASTM D 6751 and European standard EN 14214. The process of biodiesel production consists of four main phases: 1) preparation of feedstock, 2) transesterification, 3) phase separation, and 4) processing of the reaction product - purification of crude biodiesel to meet the specification provided by EN 14214. The purification process of crude biodiesel is usually carried out by two notable techniques: wet and dry washing. The most commonly used is wet process. A major drawback in the use of water in purification process is the generation of large amount of wastewater that greatly increases the biodiesel production costs followed by drying of the product, which requires additional amount of energy and time. The greatest lack of dry washing using different ion-exchange resins is the inability to remove glycerol and methanol from crude biodiesel to the limits prescribed by EN 14214 as well as the disposal problem of spent ion-exchange resins. Because of aforementioned, the use of membrane technology in the process of biodiesel purification has appeared as an alternative for the existing purification techniques. The membrane filtration is environmentally friendly and, in comparison with other two methods for biodiesel purification, requires less energy. Ultra- and/or nano- membrane filtration of biodiesel has so far provided the very good results. By membrane filtration, glycerol, methanol and water content in biodiesel can be decreased to the amounts prescribed by the standards. In frame of this work the short overview of the possibility to use the ultra- and/or nano- filtration in purification process of biodiesel will be presented.

Coal contains not only organic matter but also small amounts of inorganic constituents. More thanone hundred different minerals and virtually every element in the periodic table have been foundin coal. Commonly found group minerals in coal are: major (quartz, pyrite, clays and carbonates),minor, and trace minerals. Coal includes a lot of elements of low mass fraction of the orderof w=0.01 or 0.001 %. They are trace elements connected with organic matter or minerals comprisedin coal. The fractions of trace elements usually decrease when the rank of coal increases.Fractions of the inorganic elements are different, depending on the coal bed and basin. A varietyof analytical methods and techniques can be used to determine the mass fractions, mode ofoccurrence, and distribution of organic constituents in coal. There are many different instrumentalmethods for analysis of coal and coal products but atomic absorption spectroscopy – AAS is theone most commonly used. Fraction and mode of occurrence are one of the main factors that haveinfluence on transformation and separation of inorganic constituents during coal conversion.Coal, as an important world energy source and component for non-fuels usage, will be continuouslyand widely used in the future due to its relatively abundant reserves. However, there is aconflict between the requirements for increased use of coal on the one hand and less pollution onthe other. It’s known that the environmental impacts, due to either coal mining or coal usage, canbe: air, water and land pollution. Although, minor components, inorganic constituents can exert asignificant influence on the economic value, utilization, and environmental impact of the coal.

Limited resources compel us to turn to renewable sources, new and old, that are capable of supporting sustainable development of the human society, and satisfying the demand in energy and materials. Plant life is far from being depleted; while its potential in supporting sustainable and renewable feedstock for organic material is great. This review is devoted to the use of biomass in production of basic organic chemicals, and to the main technological directions of biomass processing. These processes mainly involve transformation of cellulose and carbohydrates into final products by chemical or fermentation technologies. Some processes are already applied in industry, while their field of application is permanently growing. A number of chemical products can be isolated from plants directly including genetically modified species. Progress in chemical technology and biotechnology enables an almost 50–70 % substitution of oil feedstock with biomass.

The presence of sulphur in coal possesses important environmetal problems in its usage. The sulphur dioxide (S02) emissions produced during coal combustion account for a significant proportion of the total global output of anthropogenic SO2. The extent of sulphur separation depends on several variables such as the form of sulphur in coal, intimacy of contact between minerals and the products of devolatilization. The total sulphur in coal varies in the range of 0.2 - 11 wt %, although in most cases it is beetwen 1 and 3 wt %. Sulphur occurs in a variety of both inorganic and organic forms. Inorganic sulphur is found mainly as iron pyrite, marcasite, pyrrhotite, sphalerite, galena, chalcopirite and as sulphates (rarely exceeds w = 0,1 %). Organic sulphur is found in aromatic rings and aliphatic functionalities usually as mercaptans, aliphatic and aryl sulfides, disulfides and thiophenes. Organic and pyritic sulphur quantities depend on coal rank. Higher rank coals tend to have a high proportion of labile sulphur. All the organic sulphur is bivalent and it is spread throughout the organic coal matrix. Sulphur occurs in all the macerals and most minerals. Vitrinite contains the major part of organic sulphur and metals. Elemental sulphur is produced during coal weathering. The depolymerization methods as pyrolysis and hydrogenation are very drastic methods wich change the structure of the coal and the sulphur groups. In the case of pyrolysis, high levels of desulphurization, in chars and additional production of liquid hydrocarbon can be achieved. Thiophenes and sulphides were the major sulphur components of tars from coal pyrolysis. Hyrdogen sulphide and the lower mercaptans and sulphides were found in the volatile matters. Hydrogen sulphide and thiophenes are practically the only sulphur products of coal hydrogenation. H2S is produced in char hydrodesulphurization. A number of options are available for reducing sulphur emissions including the utilisation of coals with low sulphur concentrations (typically < 1 wt %), the removal of cleaning prior to utilisation. The methods for the removal of sulphur from coal can be divided into: physical, chemical and microbiological. The mineral sulphur components can be removed or reduced by commercial methods of coal washing, flotation and agglomeration. A number of chemical desulphurization for the removal of, both, pyritic and organic sulphur have been advocated. The chemical desulphurization methods however, have two major drawbacks. Namely, they are often expensive and they destroy the caking properties of coal. Certain microorganisms have been used to consume or convert selectively most of the pyritic sulphur as well as some of the organic sulphur in coal. The process is also cheaper than chemical desulphurization and does not affect the caking properties of coking coal.

The paper presents a review of relevant literature on coal pyrolysis.Pyrolysis, as a process technology, has received considerable attention from many researchers because it is an important intermediate stage in coal conversion.Reactions parameters as the temperature, pressure, coal particle size, heating rate, soak time, type of reactor, etc. determine the total carbon conversion and the transport of volatiles and therebythe product distribution. Part of the possible environmental pollutants could be removed by optimising the pyrolysis conditions. Therefore, this process will be subsequently interesting for coal utilization in the future

Although the blast furnace and basic oxygen furnace are going to be primary routes for steel production in future, the steelmaking industry using the electric arc furnace route will continue to grow. The importance of high-quality steel products manufactured by direct reduction of iron ore and/or by smelting reduction processes has been increasing. In the past decade the world steel production by direct reduction rose by 140 per cent, from about 20 to about 49.5 Mt/year. In this paper major industrial processes involving direct reduction and smelting reduction of iron ore are described, and their development is analysed. Iako će proizvodnja čelika u visokim pećima i kisikovim konvertorima i nadalje biti primaran način izradbe čelika u narednom razdoblju, proizvodnja čelika u elektrolučnim pećima nastavit će se uveličavati. Međutim, povećava se važnost proizvodnje visokokvalitetnih čeličnih proizvoda dobivenih izravnom redukcijom željezne rude i/ili redukcijskim taljenjem. Zadnjih deset godina proizvodnja izravnom redukcijom povećala se za 140 %, od 20 do 49,5 MTg a -1. U ovom radu analizirani su glavni industrijski primijenjeni procesi izravne redukcije i redukcijskog taljenja kao i njihovi razvojni procesi.

Epoksidirana palmina oleinska kiselina često se smatra vrlo vrijednom oleokemijskom tvari zbog širokog raspona industrijskih primjena, uključujući kozmetiku, osobnu njegu i farmaceutske proizvode. U ovoj studiji, oleinska kiselina potekla iz palmina ulja s jodnim brojem 98,99 g/100 g, koja sadrži 75 % oleinske kiseline, 12 % linoleinske kiseline, 6,5 % palmitinske kiseline i 6,5 % stearinske kiseline, epoksidizirana je in situ proizvedenom performičnom kiselinom s vodikovim peroksidom kao donorom kisika i mravljom kiselinom kao aktivnim nosačem kisika u prisutnosti katalitičke količine anorganske kiseline. Konstanta brzine za epoksidaciju oleinske kiseline bila je 1,133 ∙ 10–3 mol–1 s–1, a energija aktivacije 91,12 kJ mol–1 pri temperaturi 75 °C. Termodinamički parametri kao što su entalpija, entropija i slobodna energija aktivacije iznosili su 88,2 kJ mol–1, −67,90 J mol–1 K–1, odnosno 88,36 kJ mol–1. Relativni podatci konverzije pokazali su da je moguće razviti epokside iz lokalnih, prirodnih i obnovljivih izvora kao što je palmino ulje. Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna. Epoxidized palm oleic acid is often regarded as a highly valuable oleochemical due to its wide range of industrial applications, including cosmetics, personal care, and pharmaceutical products. In this study, oleic acid derived from palm oil with iodine value of 98.99 g/100 g, containing 75 % of oleic acid, 12 % of linoleic acid, 6.5 % of palmitic acid, and 6.5 % of stearic acid was epoxidised by in situ generated performic acid with hydrogen peroxide as oxygen donor and formic acid as active oxygen carrier in the presence of catalytic amount of inorganic acid. The rate constant for epoxidation of oleic acid was found to be 1.133 ∙ 10–3 mol–1 s–1 and activation energy was 91.12 kJ mol–1 at temperature of 75 °C. In addition, thermodynamic parameters such as enthalpy, entropy, and free energy of activation were 88.2 kJ mol–1, −67.90 J mol–1 K–1, and 88.36 kJ mol–1, respectively. Relative conversion data showed that it was possible to develop epoxides from locally available, natural, renewable resources such as palm oil. This work is licensed under a Creative Commons Attribution 4.0 International License.