Experimental Study of Absorbent Hygiene Product Devolatilization in a Bubbling Fluidized Bed

This paper aims to investigate the usage of waste from Absorbent Hygienic Products (AHP) as a fuel for gasification or pyrolysis, two attractive routes to obtain valuable products and dispose of this kind of waste. The study experimentally investigated the devolatilization of coarsely shredded materials from diapers, in a laboratory-scale bubbling fluidized bed made of sand, as a representative preparatory step of the above-mentioned thermochemical conversions. Two versions of shredded materials were considered: as-manufactured diapers (AHPam, as a reference), and the cellulosic fraction of sterilized used diapers (AHPus). Results were presented, obtained from physical-chemical characterization of AHPam and AHPus (TGA, CHNS/O, proximate and ultimate analyses, XRF, ICP-AES, SEM-EDS), as well as from their devolatilizations at 500–600–700–800 °C under two different atmospheres (air plus nitrogen, or pure nitrogen as a reference). Generally, temperature influenced syngas composition the most, with better performances under pure nitrogen. At 700–800 °C under pure nitrogen, the highest syngas quality and yield were obtained. For AHPam and AHPus, respectively: (i) H2 equaled 29.5 vol% and 23.7 vol%, while hydrocarbons equaled 14.8 vol% and 7.4 vol% on dry, dilution-free basis; (ii) 53.7 Nl and 46.0 Nl of syngas were produced, per 100 g of fuel. Overall, AHP emerged as an interesting fuel for thermochemical conversions.

Study on the washability by using float sink test and thermal decomposition of the Mogoin gol bituminous coal

The Mogoin gol bituminous coal properties were determined by proximate and ultimate analysis and thermal behaviors performed using a HITACHI TG/DTA7300 thermogravimetry analyzer. Float sink test carried out by Russian standard GOST 4790-93. Results of the proximate and ultimate analyses showed that the coal has Vdaf=30.7%, Ad=10.6%, Cdaf=76.5% and Qdaf=7532 kcal/kg. According to the coal classification, the coal belongs to the J class of bimuminous coal. The rate of mass loss was maximum in the range 483°С. Yields and ash contents of the fraction were γб=49.9 and 5.6% respectively, when for the separation was used heavy liquid with 1.3g/cm3 density. In general, it can be concluded that the Mogoin gol coal belongs to the category of coals with very good washability. Therefore, it will be advantageous and economically viable to use coal concentrate with low-ash for further chemical processing. Могойн голын ордын нүүрсний халууны задралын болон баяжигдах шинж чанарын судалгаа Хураангуй: Дээд ангилалын чулуун нүүрс болох Могойн голын ордын нүүрсний шинж чанарыг техникийн болон элементийн шинжилгээгээр, халуун, дулаан тэсвэрлэх чанарыг термогравиметр HITACHI TG/DTA7300 маркийн багажийн тусламжтайгаар, нүүрсний баяжигдах шинж чанарыг хүнд шингэний ГОСТ 4790-93 стандарт аргаар тодорхойллоо. Нүүрсний техникийн болон элементийн шинжилгээний үр дүнгүүдээс Ж маркийн чулуун нүүрс болохыг баталж байна. Жингийн алдагдлын хурд ДТГ 483°С-ын температурын мужид хамгийн их байв. Хүнд шингэний нягтыг ихэсгэх тутам баяжмалын үнс болон гарц аажмаар ихэсгэх хандлагатай бөгөөд δ=1.3 г/см3 нягттай хүнд шингэнд нүүрсийг баяжуулбал, үнс бага Aб а=5.6%, гарц өндөртэй γб=49.9% баяжмал гарган авах боломж. Иймд бага үнстэй нүүрсний баяжмалыг цаашид гүн боловсруулалтын чиглэлээр ашиглахад давуу талтай, эдийн засгийн ач холбогдолтой байх болно. Түлхүүр үг: нүүрс, термогравиметр, жингийн алдагдал, баяжуулалт, баяжмал, хөвсөн/ живсэн фракц

The Role of Energy Valuation of Agroforestry Biomass on the Circular Economy

The use of biomass has increased significantly in recent years. In this context, the use of not valued high-potential biomass (NVHPB) is emerging as a suitable alternative. This is the case of pruning vine, pruning kiwi, scrub (heather, gorse, broom) and forest pruning. The objective of this research was to study the potential of six selected agroforestry biomasses as biofuels in thermochemical processes. For that purpose, biomass was collected by specific machinery. Proximate and ultimate analyses were carried out as well as the inorganic compounds’ determination. Then, natural and forced drying were conducted. Low heating values (LHV) between 17 and 20 MJ/kg (dry basis) were achieved in all analyzed cases. Granulometric reduction, biomass classification and densification took place. Finally, energy recovery tests through microcogeneration were carried out. Values close to 97% in cogeneration efficiency were reached (9% net electric yield and 88% thermal yield), offering an alternative to obtain clean energy.

THE RESULT OF INVESTIGATION OF COAL FROM CHANDGANA TAL DEPOSIT

Proximate and ultimate analyses showed that Chandgana Tal coal has the following properties; Wa-13.29%, Ad-12.43%, Vdaf-44.98%, Qdaf-5914 kcal/kg, C-67.56%, H-5.79%, S-1.67%, N-1.18% and O-23.8%. Pyrolysis of coal was performed at 200-700оС using small quartz reactor. With increasing temperature of pyrolysis, the yield of hard residue decreased, while the yield of tar and pyrolytic water increased. The yield of coal tar was maximum at 700оС, and reached 4.8%. At this stage, coal was pyrolized in a bigger scale retort of laboratory. The tar was separated from water and analysed by FT-IR and organic composition. Thermolysis experiments were also performed in order to explore the possibility of obtaining liquid products under mild condition. The results show that 23.5% of liquid product can be obtained at 450оC with coal to tetralin ratio (1:1.8).

A critical analysis on palm kernel shell from oil palm industry as a feedstock for solid char production

Palm kernel shell (PKS) is one of the greatly abundant residues in the palm oil industry. It possesses physiochemical characteristics that build in it a potential to serve the production of valuable products, namely, bio-fuels such as char, bio-oil, and bio-gas. This paper presents the properties of PKS as a biomass feed for the production of char. Characterizations of PKS in terms of proximate and ultimate analyses, chemical composition, and higher heating value (HHV in terms of MJ/kg) are presented and consequently compared to different oil palm biomass such as empty fruit bunch (EFB), fiber, fronds, and trunks. To illustrate and signify stability, the aforementioned characteristics are discussed for PKS-char, along with further comparison with EFB-char and coal. In addition, recent advances in char production methods from PKS are presented and compared. Simultaneously, future prospects and major challenges towards the utilization of PKS for the production of char are also addressed.

Blending Influence on the Conversion Efficiency of the Cogasification Process of Corn Stover and Coal

Characterizations of biomass and coal were undertaken in order to compare their properties and determine the combustion characteristics of both feedstocks. The study was also intended to establish whether the biomass (corn stover) used for this study is a suitable feedstock for blending with coal for the purpose of cogasification based on composition and properties. Proximate and ultimate analyses as well as energy value of both samples including their blends were undertaken and results showed that corn stover is a biomass material well suited for blending with coal for the purpose of cogasification, given its high volatile matter content which was measured and found to be 75.3% and its low ash content of 3.3% including its moderate calorific value of 16.1%. The results of the compositional analyses of both pure and blended samples of corn stover and coal were used to conduct computer simulation of the cogasification processes in order to establish the best blend that would result in optimum cogasification efficiency under standard gasifier operating conditions. The final result of the cogasification simulation process indicated that 90% corn stover/10% coal resulted in a maximum efficiency of about 58% because conversion was efficiently achieved at a temperature that is intermediate to that of coal and corn stover independently.