Modeling of chemical and physical processes in reactive porous bed

This paper contains the description of pyrolysis and flow process through porous media taking into account kinetic rate coefficient and equilibrium state of pyrolysis. Mathematical equation of pyrolysis mechanism including kinetic rate coefficient and equilibrium rate of pyrolysis, and equations like mass, momentum and energy and flow through porous zone are presented. Considered model is based on a simple geometry based on downdraft gasifier and analysed basing on CFD calculation of pyrolysis and flow of volatiles. Numerical analysis of a gas flow in an open system with mass source is carried out by means of Fluent. Calculations of the chemical and physical processes in porous bed are performed for different porosity

Utjecaj pomaka tepiha materijala i dobave zraka na protusmjerno rasplinjavanje peleta od drva listača

This work presents the results of hardwood pellet gasification with different amounts of air as a gasification medium. The effects of bed movement and the equivalence ratio (ER) on the temperature profile, gas composition, carbon conversion efficiency and the energy balance were taken into account. Slow movement of the bed promotes high combustion and reduction zones, while fast bed movement leads to high pyrolysis zones and higher caloric values of syngas. When the amount of air increased from 12 to 23 Nm3/h, the gas yield increased from 1.4 to 1.6 Nm3/kgbiomass for slow bed movement, and from 1.0 to 1.3 Nm3/kgbiomass for fast bed movement. These results show that in both Cases similar specific energy values were obtained. However, in Case 1 lower fuel consumption was reached. Chemical energy in the syngas represents 80 % of the output energy for slow bed movement (265 MJ/h) and 75 % for fast bed movement (295 MJ/h). A significant effect of bed movement in the reactor suggests that the gasifier could be considered as a flow reactor, and additionally the fast movement of the bed with 20 Nm3/h of supplied air yielded the highest-quality gasification process. Moreover, fast bed movement in the reactor leads to a high amount of generated char with high energy potential.U radu su prikazani rezultati rasplinjavanja peleta od drva listača različitim količinama zraka kao sredstvom za rasplinjavanje. U ispitivanju je uzet u obzir utjecaj pomaka tepiha materijala i omjera ekvivalencije (ER) na temperaturni profil, sastav plina i učinkovitost pretvorbe ugljika te na energetsku ravnotežu. Usporeni pomak tepiha materijala pospješuje zone dobrog izgaranja i redukcije, dok brzi pomak tepiha materijala rezultira visokim zonama pirolize i višim kalorijskim vrijednostima sintetskog plina. Kada je količina zraka porasla s 12 na 23 Nm3/h, prinos plina povećao se s 1,4 na 1,6 Nm3/kgbiomase pri laganom pomaku tepiha materijala, a od 1,0 do 1,3 Nm3/kgbiomase pri brzom pomaku tepiha materijala. Ti rezultati pokazuju da su u oba primjera dobivene slične vrijednosti specifične energije. Međutim, u prvom je primjeru postignuta niža potrošnja goriva. Kemijska energija u sintetskom plinu čini 80 % izlazne energije pri laganom pomaku tepiha materijala (265 MJ/h) i 75 % pri brzom pomaku tepiha materijala (295 MJ/h). Znatan učinak pomaka tepiha materijala u reaktoru sugerira da se rasplinjač može smatrati protočnim reaktorom, a dodatno brz pomak tepiha materijala s 20 Nm3/h dobave zraka omogućio je najkvalitetniji proces rasplinjavanja. Štoviše, brzi pomak tepiha materijala u reaktoru dovodi do nastanka velike količine pougljenjenog materijala s visokim energetskim potencijalom

Prospective analysis of the impact of adjuvant treatment with external beam radiation therapy and vaginal brachytherapy on health-related quality of life in patients with early-stage endometrioid endometrial carcinoma

Objectives: Our study evaluates the impact of adjuvant treatment with external beam radiotherapy (EBRT) combined with vaginal high dose rate brachytherapy (HDR BT) on health related quality of life (HRQL) in patients with early stage endometrioid endometrial carcinoma. Material and methods: From March 2019 to February 2021, 60 patients were enrolled with early stage endometrioid endometrial carcinoma, and qualified to adjuvant treatment after hysterectomy. HRQL was assessed using the EORTC QLQ-C30 questionnaire, with the endometrial cancer-specific HRQL module EORTC QLQ-EN24. Questionnaires were completed in four timepoints during adjuvant radiotherapy. Results: A significant decrease in mean global health status / quality of life (p < 0.001) and role functioning (p = 0.028) was noted, as assessed in EORTC QLQ-C30 scale. Among the EORTC QLQ-C30 symptoms scales, significant differences were noted in the fatigue scale (p = 0.003), pain scale (p = 0.001), constipation scale (p < 0.001) and diarrhea scale (p < 0.001) over time. The EORTC QRQ-EN24 analysis showed significant deterioration in the urological symptoms scale (p < 0.001), gastrointestinal symptoms scale (p < 0.001) and in the mean pain in back and pelvis scale (p = 0.003). Conclusions: Adjuvant radiotherapy in patients with early-stage endometrioid endometrial cancer after hysterectomy is associated with worse quality of life, especially due to the toxicity of the treatment in relation to the gastrointestinal tract and urinary system

The impact of adjuvant treatment with external beam radiotherapy and vaginal brachytherapy on health-related quality of life in patients with early-stage endometrioid endometrial carcinoma — initial results of a prospective study

Objectives: Our study evaluates the impact of adjuvant treatment with external beam radiotherapy (EBRT) combined with vaginal high-dose-rate brachytherapy (HDR BT) on health-related quality of life (HRQL) in patients with early-stage endometrioid endometrial carcinoma. Material and methods: We assessed HRQL of patients based on the EORTC QLQ-C30 questionnaire, with endometrial cancer specific HRQL module — EORTC QLQ-EN24. From March 2019 to April 2020 we enrolled 20 patients with early-stage endometrioid endometrial carcinoma, qualified for adjuvant treatment after hysterectomy. We compared the scores measured with the questionnaires at the beginning and at the end of the treatment. Results: There was a statistically significant decrease in the mean of global health status/quality of life assessed according to the EORTC QLQ-C30 scale, from 62.25 ± 13.12 at the beginning of the adjuvant radiotherapy to 55.85 ± 14.68 at the end of the treatment (p = 0.047). The mean appetite loss score was higher at the onset of the treatment as compared to its value after EBRT, 19.9 ± 27.33 vs 11.6 ± 19.52 (p = 0.043). Similarly to the mean constipation score, which was 29.85 ± 30.40 vs 11.6 ± 19.52 (p = 0.013). The mean diarrhoea symptom scale increased from 16.55 ± 20.16 to 56.75 ± 36.10 (p = 0.001). In the EORTC QLQ-EN24 scales, gastrointestinal symptoms scores were higher at the end of the treatment, (with the mean of 26.45 ± 22.76) as compared to 14.30 ± 16.52 at the beginning of EBRT (p = 0.003). Conclusions: Patients who receive adjuvant radiotherapy have decreased quality of life during the treatment reporting more serious gastrointestinal symptoms. The potential risk of treatment-related toxicity should be taken into account during the treatment planning process in order to minimize the deterioration of HRQL

Possible Utilization of Distillery Waste in the Carbonization Process

This paper characterizes the carbonization process in terms of the utilization of distillery waste in a laboratory-scale reactor. Due to the increase in market prices of wood and environmental protection laws, biomass waste, including distillery waste, is a potential source for biochar production. An experimental investigation of the carbonization process was carried out for different mixtures of distillery waste and oak sawdust. The obtained results showed that due to the European Standard, biochar from distillery waste could be used for the production of charcoal briquettes for barbecue applications. In addition, biochar from carbonization samples with 66, 50, and 33% distillery waste meet the standards defined by the International Biochar Initiative for HMs content. The analysis of the dynamics of the heating rate showed that adding wood to distillery waste significantly shortens the carbonization process, but this reduces the number of bio-oils produced and its calorific value

GPR: A Python implementation of an extremely simple classifier based on fuzzy logic and gene expression programming

In this work, we present a Python-based implementation of an extremely simple classifier (GPR), which combines gene expression programming (GEP) features and the algebraic representation of the ’if-then’ fuzzy rules theory of the Takagi–Sugeno fuzzy inference system. Generated fuzzy metarules are highly interpretable and suitable for many applications. We provide an open-source Python implementation of the GPR algorithm to enable the use of the algorithm without any commercial software tools and open access to the research community. We also added enhancements to improve the readability and interpretability of the rules

Kemijska i fizikalna svojstva borovine tijekom pirolize

This paper examines the influence of temperature on several physical properties of wood. The results demonstrated that devolatilization during pyrolysis greatly affects the inner structure of wood, followed by changes in volume, mass, density and shape. The research showed that a decrease in wood density caused a significant increase in permeability. Data on pyrolytic gases, char composition and calorific value measurements of these products are also presented. The results showed that the lower heating value (LHV) of pyrolytic gas can reach 12 MJ/Nm3 at 600 °C and the higher heating value (HHV) of char can reach 34 MJ/kg for 700 °C. The analysis of the calorific values of pyrolytic gases and char showed that the thermal conversion of biomass can lead to the generation of good quality gaseous and solid fuels.U radu se razmatra utjecaj temperature na neka fizikalna svojstva drva. Rezultati su pokazali da isplinjavanje tijekom pirolize uvelike utječe na unutarnju strukturu drva te na promjene njegova volumena, mase, gustoće i oblika. Analizom rezultata istraživanja može se zaključiti da smanjenje gustoće drva uzrokuje znatno povećanje propusnosti drva. U radu se prikazuju i podaci o pirolitičkim plinovima, sastavu ugljena i mjerenju njihovih kalorijskih vrijednosti. Rezultati su pokazali da donja ogrjevna vrijednost (LHV) pirolitičkog plina može dosegnuti 12 MJ/Nm3 pri 600 °C, a gornja se ogrjevna vrijednost (HHV) ugljena kreće i do 34 MJ/kg pri 700 °C. Analiza kalorijskih vrijednosti pirolitičkih plinova i ugljena pokazala je da se toplinskom pretvorbom biomase mogu proizvesti kvalitetna plinovita i kruta goriva

Kontenerowa instalacja zgazowania odpadów komunalnych w Nowym Dworze

Chociaż odpady komunalne nadal traktowane są jako problem, to coraz częściej postrzegane są jako źródło różnego rodzaju korzyści. Cały ciąg procesów: odzysk, recykling i  przetwarzanie termiczne służą zamianie odpadów w użyteczne materiały lub energię. W  tym zestawieniu termiczna przeróbka ma niższy priorytet niż recykling ale jej udział może sięgać 1/3 całego strumienia śmieci, co świadczy o jej znaczeniu i potencjale