Fixed bed pyrolysis of biomass solid wastes for bio-fuels in Brunei Darussalam

Author(s):  
M.N. Islam ◽  
M.H.M. Ali ◽  
H. Said ◽  
F.N. Ani
2020 ◽  
Vol 9 (1) ◽  
pp. 770-782
Author(s):  
Tianpeng Li ◽  
Jing Fan ◽  
Tingting Sun

AbstractA novel porous ceramsite was made of municipal sludge, coal fly ash, and river sediment by sintering process, and the performance of batch and fixed-bed column systems containing this material in the removal of acid red G (ARG) dye from aqueous solutions was assessed in this study. The results of orthogonal test showed that sintering temperature was the most important determinant in the preparation of porous ceramsite, and it possesses developed pore structure and high specific surface area. Batch experiment results indicated that the adsorption process of ARG dye toward porous ceramsite was a spontaneous exothermic reaction, which could be better described with Freundlich–Langmuir isotherm model (R2 > 0.992) and basically followed the pseudo-first-order kinetic equation (R2 > 0.993). Column experiment results showed that when the porous ceramsite was used as packing material, its adsorption capacity was roughly improved by 3.5 times compared with that in batch system, and the breakthrough behavior was simulated well with Yoon–Nelson model, with R2 > 0.954. This study suggested that the novelty man-made porous ceramsite obtained from solid wastes might be processed as a certain cost-effective treatment material fit for the dye removal in aqueous solutions.


2004 ◽  
Vol 49 (11-12) ◽  
pp. 287-294 ◽  
Author(s):  
I. Comett ◽  
S. Gonzalez-Martinez ◽  
P. Wilderer

Biofilms growing on different carrier media have a different response to the nutrients contained in wastewater. Biofilms have proven to be an alternative to the treatment of wastewater containing higher concentrations of contaminants. The main objective of this research was to compare two biofilm support media for the treatment of leachate from the anaerobic fermentation of solid wastes. The removal of organic matter and ammonia was achieved in two fixed bed biofilm reactors containing Kaldnes® and Linpor® support materials with specific surface areas of 490 and 270 m2/m3, respectively, and operating under the sequencing batch procedure during 204 days. The Linpor reactor achieved higher total COD removal than the Kaldnes reactor (47% and 39%, respectively). Linpor was shown to be less sensitive to influent COD changes than Kaldnes. The effluent total COD values of Kaldnes were higher than Linpor. The dissolved COD removal was 21% for both reactors. The average ammonia removal for Linpor was 72% and 42% for Kaldnes. The matrix of Linpor allows higher concentrations of microorganisms (as dry mass) than Kaldnes. The dry mass concentration was related to the "active" exposed surface area of the biofilm. This is considered to be the cause for the better performance of Linpor when compared with Kaldnes.


2017 ◽  
Author(s):  
Mohammad Nurul Islam ◽  
Mohamed Hairol Md Ali ◽  
Miftah Haziq

2021 ◽  
Author(s):  
Feng Tang ◽  
Yuqi Jin ◽  
Yong Chi ◽  
Zhongxu Zhu ◽  
Jie Cai ◽  
...  

Abstract The co-pyrolysis tar formed from microcrystalline cellulose (MCC) and polyethylene (PE) was used to study their further conversion path under the effect of steam. This paper addressed the yield and transformation of tar with different steam/feedstock mass ratios (S/F= 0.8, 1.6) in a two-stage fixed-bed when the two stages furnace temperature was set at 600℃ and 800℃, separately. Compared with pyrolysis, steam promoted tar cracking effectively, the tar yield decreased at least 1/3. However, with the addition of steam, the cracking effect of tar is not further improved. The tar yield depended more on the PE content in the mixture, which was enhanced with PE increment. Besides, the H/C atom ratio was related to the conversion path of tar. Steam was beneficial to the cracking of compounds, but the generated hydrogen radicals affected the direction of the subsequent reaction. The steam mainly promotes the cracking of long-chain hydrocarbons, accompanied by cyclization and aromatization when the steam was limited. Nevertheless, these reactions were hindered when the steam was excessive due to the apparent effect of hydrogenation. In this process, the short-chain hydrocarbons come to recombine instead of cyclization and aromatization.


2018 ◽  
Vol 215 ◽  
pp. 01027
Author(s):  
Akbarningrum Fatmawati ◽  
Tuani Lidiawati ◽  
Stephen Hadinata ◽  
Mikhael Adiarto

Agricultural solid wastes present abundantly on earth as crops harvesting as well as processing are countinuesly run. Banana peels are one of agricultural solid wastes produced anywhere the banana processing presents. The peels present abundantly in tropical countries such as Indonesia. The carbohydrate content of banana peels make it useful for the production of many chemicals, including feed. Meanwhile the large need in feed in farming including fish farming could prevent farmer to obtain substantial profit. This research studied the possibility of banana peel as one of abundant Indonesian agricultural solid waste to be utilized as fish feed which is known requiring certain level of protein content. This was done by fermenting the peels in fixed bed reaction mode using surface aeration and non-aeration. The fermentation was conducted using yeast Saccharomyces cerevisiae Y1536 and Rhizopus Oryzae FNCC 6157. The reaction time was varied for 1, 3, and 5 days. The important parameters studied were protein contents, and amylase activity of the fermented banana peels. Despite aeration indicated more operational cost, it showed significant impact on the fermentation of banana peels. The best condition for fermentation using Saccharomyces cerevisiae Y1536 were 5 day fermentation with surface aeration which result in the increase of protein content up to 4.05%, the decrease of fiber content up to 1.08%, and amylase activity of 9.99 DP. Whilst the fermentation using Rhizopus Oryzae FNCC 6157 obtained its best result at 1 day fermentation with aeration, which are protein content increase up to 4.04% and fiber content decrease up to 0.69%. However, the fermentation using this mold showed its best amylase activity result of 12.75 DP at 5 day surface aerated fermentation.


Soil Systems ◽  
2020 ◽  
Vol 4 (2) ◽  
pp. 34
Author(s):  
Despina Vamvuka ◽  
Stelios Alexandrakis ◽  
George Alevizos ◽  
Antonios Stratakis

In the context of the current environmental policies of the European Union promoting the recycling and reuse of waste materials, this work aimed at investigating the environmental impact of ashes produced from the co-combustion of municipal solid wastes with olive kernel in a fixed bed unit. Lignite fly ash, silica fume, wheat straw ash, meat and bone meal biochar, and mixtures of them were used as stabilizing ash materials. All solids were characterized by physical, chemical and mineralogical analyses. Column leaching tests of unstabilized and stabilized ash through a quarzitic soil were conducted, simulating field conditions. pH, electrical conductivity, chloride, sulphate and phosphate ions, major and trace elements in the leachates were measured. The results showed that alkaline compounds were partially dissolved in water extracts, increasing their pH and thus decreasing the leachability of heavy metals from the ash. Cr leached from unstabilized ash reached a hazardous level. Upon the stabilization of ash, the concentrations of heavy metals in the extracts were reduced between 9% and 100%, and were below legislation limits for disposal, apart from Cr. The latter was achieved only when meat and bone meal biochar was used as stabilizer. Entrapment of ash elements was assigned to the amorphous silica and to the phosphates of the stabilizing materials, as well as complexed silicates formed during the process.


Author(s):  
Guanyi Chen ◽  
Qiang Li ◽  
Xiaoyang Lv ◽  
Na Deng ◽  
Lifei Jiao

Biomass is quite abundant in the world, particularly in some countries like China. China has large quantities of straw and/or stalk-origin biomass resources and the attention is currently being paid to the exploitation of these resources to produce energy products via different technical solutions, among of which pyrolysis of biomass to produce hydrogen-rich gas is very promising as hydrogen is a very clear energy carrier. In this work, pyrolysis of rice straw, corn stalk and sawdust was carried out in a two-stage reactor (the first-stage reactor is a conventional fixed-bed pyrolyser, and the second-stage reactor is a catalytic fixed bed) to produce hydrogen-rich gas. The effect of catalytic bed on the pyrolysis behaviour have been investigated, with the emphasis on final product particularly hydrogen. The operation of the catalytic reactor appears significant in promoting biomass pyrolysis towards the production of gaseous products, especially hydrogen. At 750°C of the pyrolyser with rice straw as fuel, the use of the catalytic bed leads to the increases of gas yield from 0.41 Nm3/kg to 0.50 Nm3/kg, approximately 22% increase, and of H2 concentration from 33.79% to 50.80% in volume, approximately 50.3% increase, respectively. Compared with calcined dolomite, fresh nickel-based catalyst shows stronger catalytic effect on the pyrolysis of rice straw as its use in the catalytic bed results in the increase of gas yield from 0.41 Nm3/kg to 0.56 Nm3/kg, approximately 36.6% increase, and the increase of H2 concentration from 33.79% to 59.55% in volume, approximately 76.2% increase. Furthermore, two catalysts follow the same trend for the pyrolysis of corn stalk and sawdust. At temperature of 815°C, catalysts also follow the same trend. Catalytic bed can significantly reduce the level of tar which is carried out with the producer gas, to less than 1% of original level. Catalyst load or gas space velocity (hourly) has the influence on the gas yield and H2 concentration. 30% of load, i.e. gas space velocity (hourly) 0.9 × 104 h−1, appears reasonable. Beyond that, gas yield and H2 concentration remain almost unchanged.


2018 ◽  
Vol 91 (4) ◽  
pp. 630-637 ◽  
Author(s):  
Lei Deng ◽  
Jiaming Ye ◽  
Xi Jin ◽  
Defu Che

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