Straw Waste Research Articles

UTILIZATION OF RICE STRAW WASTE INTO COMPOST FERTILIZER IN GAMPONG COT CUT, KUTA BARO SUB-DISTRICT ACEH BESAR DISTRICT

This Community Service (CS) activity aims to provide information to the community about the utilization of rice straw waste into compost in Gampong Cot Cut, Kuta Baro Sub-district, Aceh Besar District, by utilizing natural resources in the surrounding area so that it can improve the community's economy. Poliven lecturers and students to find out the potential and situation in Gampong Cot Cut Furthermore, planning activities that will be carried out and demonstrated to the community of Gampong Cot Cut. Then the second stage is providing direct explanations to the community about the utilization of rice straw waste in compost fertilizers. The stages of how to make it are: The available rice straw waste is chopped/reduced in size and then mixed with cow dung. Then the EM4 solution is added. The mixture is stirred evenly and tightly closed, and the fermentation process is carried out for 1 month. The CS activity carried out in Gampong Cot Cut, Ingin Jaya Sub-district, Aceh Besar District has been carried out very well and smoothly thanks to the assistance of several parties, namely LPPM Politeknik Indonesia Venezuela, support from the apparatus, and the community of Gampong Cot Cut. This CS activity is useful for developing the potential of the community to be more creative in creating new things, and the community is greatly helped by the demonstration of making rice straw compost.

Enhanced biomethane production by thermophilic high-solid anaerobic co-digestion of rice straw and food waste: Cellulose degradation and microbial structure

Enhanced biomethane production by thermophilic high-solid anaerobic co-digestion of rice straw and food waste: Cellulose degradation and microbial structure

Rice straw -derived lignin-based carbon nanofibers as self-supporting electrodes for supercapacitors and lithium-ion batteries

Self-supporting carbon fibers are extensively employed as active components in energy storage systems due to their tunable microstructures, large specific surface area, affordability, and excellent electrical conductivity. Nevertheless, conventional methods for producing carbon fibers typically involve complicated synthesis processes, environmental pollution, and high energy consumption. In this study, lignin-based carbon nanofibers (LCNFs) were prepared through electrospinning and subsequent heat treatment. The morphologies, crystal structures, and specific surface area of the as-prepared LCNFs were characterized using scanning electron microscopy, X-ray diffraction and nitrogen sorption isotherms. The influence of lignin content on the on the structural, morphological, and electrochemical properties of the carbon nanofibers were examined, particularly in their applications as supercapacitor and lithium-ion battery anode materials. The as-prepared LCNF-2 possess the highest specific surface area of 468.3 m2 g−1. As a self-supporting electrode in supercapacitors (SCs), the LCNF-2 delivered 256.3 F g−1 at 0.2 A g−1, and capacitance retention of 62.0 % at the current density raised from 0.5 to 10 A g−1. The assembled LCNF-2//LCNF-2 symmetric supercapacitor demonstrated a specific capacitance of 168 F g−1 at 5 A g−1, maintaining 100 % capacitance retention after 10,000 cycles. Additionally, it achieved an energy density of 5.6 Wh kg−1 at a power density of 1250.0 W kg−1. As a lithium-ion batteries (LIBs) anode, the LCNF-2 showed a discharge specific capacity of 1108.3 mAh g−1 and a discharge specific capacity of 377.3 mAh g−1 in the first cycle, with a capacity retention rate of 84.6 % after 100 cycles at 1C. This work offers a novel approach for the high-value utilization of agricultural waste straw lignin in energy storage devices.

Study of Flax Shive Pellet Combustion in Cyclone-Bed Furnace with Bubbling Fluidised Bed

Flax shive is a by-product of flax processing enterprises. It can be used as fuel in municipal and industrial energy enterprises along with other types of agricultural waste (straw, sunflower husk, rice husk, etc.). The use of agricultural waste as fuel is very important for the sustainable development of municipal and industrial energy in small towns and villages, as it allows for the recycling of waste, a reduction in greenhouse gas emissions and the creation of new jobs in the production of pellets from waste. Flax shive has a low bulk density in its initial state. To achieve a significant reduction in transport and storage costs, flax shives should be produced as pellets. The pellets from flax shives can be combusted in a fluidised bed of inert material. To do this, an optimal hydrodynamic structure of the bed should be created, taking into account the rapid heating of pellets placed in the bed, as well as the efficient combustion of coke residue and volatile substances. Studies on a cold model showed that the hydrodynamic structure of the fluidised bed is influenced by the way the inlet air is distributed into the fluidised bed. Studies were carried out with flat inlet air distribution, with convex inlet air distribution (64% of the total amount of air for fluidisation is supplied under the central part of the air distribution grate) and with concave air distribution (80% of the air for fluidisation is supplied under the peripheral part of the air distribution grate). Concave air distribution creates optimum conditions for pellet combustion. Intensive particle circulation is noted in the lower part of the fluidised bed, which prevents the pellets entering the bed from settling on the air distribution grate. At the same time, in the upper part of the bed, conditions for uniform thermal destruction of pellets across the entire cross-section of the furnace are created. Experiments on a pilot furnace with vortex afterburning of volatile substances in the furnace’s disengaging space were carried out using a grid plate, forming a concave inlet air velocity profile. The combustion efficiency of pellets made of flax shive in such a furnace was 98.91–99.84%.

Duodenum and Caecum Microbial Shift Modulates Immune and Antioxidant Response Through Energy Homeostasis in Hu Sheep Fed Vegetable Waste and Rice Straw Silage.

The gradual decline in feed resources for livestock needs alternate ways to ensure non-stop feed supply throughout the year. The objective of this study was to evaluate the impact of vegetable waste and rice straw silage (VTRS) on immune response, antioxidant status, and microbial changes in duodenum and caecum in Hu sheep. Eight healthy male Hu sheep were randomly distributed into control (fed farm roughage) and VTRS (fed vegetable waste silage) groups for 35 days. Results had shown that silage had less mycotoxin content (p < 0.05). The VTRS increased butyrate content in duodenal digesta, while acetate, butyrate, total volatile fatty acids (TVFA), and valerate were enhanced in caecal digesta (p < 0.05). The VTRS also increased amylase activity in duodenum and ileum tissues, along with GLUT2 and SGLT1 expressions. In serum, Interleukin-10 (IL-10) concentration and total antioxidant capacity (T-AOC) were increased while malondialdehyde (MDA) was decreased. An increase in T-AOC and GSH-Px activity was also observed, along with increased IL-6, immunoglobulin A (IgA), and catalase in duodenum tissue (p < 0.05). Prevotella was increased in the duodenum and caecum, with Prevotellacae UCG-001 and Christensenellacae R-7 group representing the VTRS group in the duodenum (p < 0.05). KEGG pathway prediction also indicated the enrichment of energy metabolism-related pathways. Significant microbes had shown a significant correlation with immune parameters. It can be concluded that vegetable waste silage has the ability to improve antioxidant status, enhance energy metabolism, and balance intestinal microbiota in Hu sheep.

Straw Return with Biodegradable Film Mulch: A Synergistic Cultivation Measure with Environmental and Economic Benefits Based on Life Cycle Assessment

Straw return and plastic film mulching are two critical management measures that not only maintain high and stable crop yields, but also have a significant impact on the ecological environment. However, there is still a lack of research on the comprehensive effects of straw return and different film mulching treatments on the ecological environment. Thus, a 2-year field experiment was conducted and six treatments, which included two main treatments, namely straw return (SR) and non-straw return (NR), and three sub-treatments, namely no film mulching (CK), plastic film mulching (PM) and fully biodegradable film mulching (BM), were applied in a garlic cropping system. Based on the life cycle assessment method, six endpoint damage categories, resource consumption, global warming potential, environmental acidification, eutrophication, human health, and ecotoxicity, were assessed. Furthermore, we also evaluated the costs and economic benefits of the six treatments and optimized the treatment of used mulch and straw off-farm. The results indicated that the environmental impacts of the six endpoint damages in the garlic cropping system were ranked as ecotoxicity, eutrophication, environmental acidification, global warming potential, human health, and resource consumption. The SR-BM treatment had the lowest life cycle environmental impact composite index at 27.68 per unit area, followed by SR-PM at 27.75. All six endpoint damage categories for the PM and BM treatments were lower than the CK treatment per t of yield, with the SR-BM treatment being the most economically efficient, yielding at 3691.03 CNY·t−1 and exceeding that of the SR-CK treatment by 7.26%. Fertilizer inputs were the primary contributor to resource consumption, global warming potential, environmental acidification, eutrophication, and ecotoxicity, accounting for about 72.80% of these five environmental impacts. Crop protection significantly affected human health, and garlic mulching helped minimize pesticide use, thereby reducing potential health impacts. Compared to straw incineration and waste mulch power generation, straw power generation and waste mulch recycling granulation offered positive environmental benefits and were more effective offset strategies. In conclusion, straw return with biodegradable mulch is a synergistic cultivation measure that offers both environmental and economic benefits. For straw return with plastic film mulch, environmental impacts can be reduced by waste mulch recycling granulation.

Fermentasi Hijauan Sebagai Pakan Alternatif Berkualitas Untuk Ternak

Samaelo Village is one of the villages in Bone Regency, South Sulawesi. Which has quite extensive rice farming land. The abundant rice farming results have their own impacts in the form of accumulation of rice straw waste. Rice straw waste is usually burned when it is dry or left to rot. The way rice straw waste is managed has caused air and water pollution due to smoke from burning or the smell of rotting rice straw. Therefore, to minimize pollution caused by rice straw waste, this activity aims to provide training in processing rice straw waste using fermentation techniques into animal feed to farmer and livestock groups in Samaelo Village. The method of implementing the activities includes observation, socialization, demonstration, and evaluation. Based on the results of the implementation of the activities, it is known that (1) the Samaelo village livestock group began to understand the benefits of using fermented straw as animal feed. (2) the livestock group began to be interested in making and trying to provide the results of fermented straw processing to livestock.

Towards an eco-social circular economy: exploring the feasibility study of pyrolysis on agricultural feedstocks

AbstractThe agricultural sector is challenging to decarbonise due to its reliance on heavy machinery and fossil fuels, which face issues when decarbonising via methods such as electrification. However, agriculture provides opportunities to generate renewable energy via biomass sources due to their abundance within this sector. This feasibility study used a continuous auger pyrolysis system to assess how straw waste from a medium-scale arable farm could convert energy from an external electrical source into usable chemical potential. Wheat, barley, oil seed rape (OSR), and bean straw have all been processed and pyrolysed under different temperatures and auger feed rates. The syngas product was then analysed, considering its composition and the lower heating value. Results indicate that the percentage of carbon monoxide and hydrogen and the total volume of syngas increased with temperature. In addition, the syngas’ energy quantity increased despite the product’s decreasing heating value. The case study’s annual energy demand was equal to 14.4% of the 3900 GJ maximum potential contained within the syngas, and thus it can be concluded that there is potential for the application of this system towards a circular economy. The system’s cold gas, net, and electrical conversion efficiency were also assessed with maximum values of 37.1%, 30.1%, and 174.4%, respectively. Furthermore, the statistical analysis confirms high predictability for wheat, barley, bean, and OSR feedstocks, with a general linear model showing high accuracy across all.

A Potential Pozzolanic Material consisting of Rice Straw Ash and Fly Ash for Geopolymer Mortar Production-based Cementitious System

Rice straw waste, among other issues, is a significant source of air pollution and methane emissions from biological decomposition. This study examines the use of Rice Straw Ash (RSA), when combined with Fly Ash (FA) and Laterite Soil (LS), as a pozzolan in cementitious systems. The study's purpose is to examine the microstructure and compressive strength of a geopolymer mortar composed of FA, RSA, and LS. The RSA is activated with sodium hydroxide (NaOH), an alkaline activator, with concentrations of 6, 12, and 15 M NaOH. After air and water curing for 3, 7, and 28 days, the compression strength of the geopolymer mortar was tested. To determine the dominant compound of the pozzolan reactions that were generated in cementitious systems, Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) were employed. When geopolymer mortar is cured in air and water, its compressive strength increases with age. This is due to the fact that RSA, FA, and LS have the ability to form iron oxide (Fe3O4) in the amorphous phase and have a strong bond with alumina (Al2O3) and silica (SiO2). The material's fineness affects its compressive strength as well. This study intends to replace cement in mortar and concrete utilizing environmentally friendly materials. Furthermore, the creation of geopolymer material usually requires the use of oven heat to enhance the geopolymerization procedure. However, this study shows that this method does not require oven heat.

Effects of biochar-loaded microbial agent in regulating nitrogen transformation and integration into humification for straw composting

Exogenous additives can impact organic matter transformation in composting, but their effects on nitrogen conversion and humification in straw composting require clarification. This study investigated how rice husk biochar-loaded microbial agent (RM) affects nitrogen transformation and humification during straw composting. Results showed that the addition of RM enhanced ammonia oxidation and assimilation during composting, leading to a 10.32%–22.27% increase in total nitrogen content. Furthermore, the RM treatment enriched nitrogen-converting microbes such as Longispora and Coprinopsis, enhancing synergistic relationships among microbes, facilitating the accumulation of pivotal nitrogenous humus precursors (amino acid nitrogen), and promoting humus formation. This research not only guides reducing nitrogen loss during composting and elucidating the relationship between nitrogen transformation and humification but also contributes to enhancing bioconversion efficiency of agricultural waste to explore new ways of straw waste management.

Numerical simulation and experimental study of hydrogen production from chili straw waste gasification using Aspen Plus

Biomass gasification is a promising method for hydrogen production. This study systematically models the gasification of chili straw waste (CSW) using the Aspen Plus simulator, focusing on the effects of gasification agents—steam, air, and oxygen—and sensitivity analyses of key parameters. Results show that under optimal steam gasification conditions, with a temperature of 700 °C and atmospheric pressure, hydrogen concentration reached 59.61%, while the lower heating value (LHV) decreased to 6.65 MJ/m3 due to CO reduction. In air gasification, increasing air input reduced hydrogen and CO concentrations by 18.5% and 26.6%, respectively, while LHV dropped by 52.5%. Oxygen-enriched gasification significantly improved hydrogen and CO concentrations, increasing LHV by 129.4% as the oxygen fraction rose. Sensitivity analysis revealed that optimal hydrogen production in air-steam gasification occurred with a low equivalence ratio of 0.18, moderate temperature around 700 °C, and atmospheric pressure. These findings highlight the critical role of temperature, pressure, and gasifying agents in optimizing hydrogen production, providing a basis for improving the efficiency of biomass gasification systems.

One-step synthesis of novel nitrogen-doped biochar from N-rich waste straw particleboard for efficient Pb(Ⅱ) adsorption

Converting agricultural waste into biochar through pyrolysis toward water pollution remediation fully embodies the “waste control by waste”. Herein, the N-rich waste straw particleboard was converted into N-doped biochar (NBC) as Pb(Ⅱ) adsorbent by one-step pyrolysis. Results showed that the presence of 4,4-diphenylmethane diisocyanate (MDI) successfully introduced N heteroatoms (pyridinic N, pyrrolic N, and graphitic N) and promoted the formation of pore structure. The obtained 7NBC-5 exhibited promising adsorption performance for Pb(Ⅱ) with maximum adsorption capacity of 204.66 mg/g, and high tolerance to various co-existing ions. Moreover, the adsorption efficiency of Pb(Ⅱ) by 7NBC-5 remained consistent at approximately 81.5 % after four successive adsorption–desorption cycles, showing good reuse performance. The adsorption of Pb(Ⅱ) on 7NBC-5 was well described by Langmuir isotherm model and pseudo-second-order kinetic model, implying that the Pb(Ⅱ) was adsorbed onto 7NBC-5 by monolayer, and chemisorption was the main rate-limiting step. The mechanism of Pb(Ⅱ) adsorbed on 7NBC-5 involved electrostatic attraction, surface complexation, pore filling, cation-π interactions, and ion exchange. N doping significantly enhances the complexation and cation-π interaction between 7NBC-5 and Pb(Ⅱ). This study proposes a method to simultaneously address the issues of waste resource utilization and heavy metal pollution in a non-harmful manner.

The treasured giants: a current overview on agricultural, nutritional, bioactive, and economic potential of Macrocybe Species (Agaricales, Basidiomycota).

Macrocybe is a well-studied genus in the family Callistosporiaceae (Basidiomycota). Currently, the genus comprises eight species with worldwide distribution. All species in this genus are relatively large compared to other edible mushrooms and are commonly consumed by locals. Cultivation methodologies have been developed for several species of the genus, including M. gigantea, M. crassa, M. titans, and M. lobayensis. These mushrooms can be cultivated in lignocellulosic wastes such as sawdust, straw, and other agro-industrial wastes. The nutritional compositions have been identified for M. gigantea, M. crassa, and M. lobayensis, revealing that they are rich in fibers, proteins, and various vitamins. Although these mushrooms are of culinary significance, precautions should be taken when consuming them due to their potential cyanic toxicity. In addition to being rich in different nutrients, Macrocybe species possess medicinal properties such as antimicrobial, antioxidant, immunomodulatory, anticancer, anti-inflammatory, hepatoprotective, and several other beneficial effects. Several species are commercially available in countries like China and Thailand, and the commercial potential is high due to the large size, taste, and long shelf life of these mushrooms. There is significant potential for cultivating species of this genus and introducing their artificial cultivation practices to various counties worldwide. Diverse value-added products can also be produced using Macrocybe species.

Machine learning-assisted optimization of 5-hydroxymethylfurfural yield from straw by microwave hydrothermal conversion

The complex and compact structure of straw represents the primary obstacle to its high-value conversion. This research integrated ball milling depolymerization, microwave hydrothermal conversion and machine learning methodology to gradually optimize and enhance the conversion potential of straw to 5-hydroxymethylfurfural (HMF). The findings indicated that the HMF yield of from straw, following ball milling depolymerization and direct microwave hydrothermal conversion, ranges between 0.10% and 0.45%. However, under acid-catalyzed microwave hydrothermal conditions, the HMF yield markedly increased to 2.35%–2.95%. It was noteworthy that AlCl3, Ca-zeolite, and Mg-zeolite increased the maximum HMF yield to 9.47%, 7.67%, and 9.04%, respectively. Based on these findings, introducing organic solvents to form a biphasic system could further increase the HMF yield to 10.63% (75% MIBK addition scenario). Finally, machine learning prediction indicated that the HMF yield could be optimized to 11.13 wt% in the biphasic system with 0.08 g AlCl3 per 0.2 g reaction material and 7.5 mL MIBK per 10 mL reaction solution and pH 1.25 under microwave hydrothermal at 190 °C for 0.75 min. The findings of this study provide a valuable reference point for the upcycling of straw and other biomass wastes, thereby facilitating the development and utilization of renewable resources.

Facile electrospinning-electrospray method to fabricate flexible rice straw-derived cellulose acetate/TiO2 nanofibrous membrane with excellent photocatalytic performance

A novel and facile electrospinning-electrospray (EE) method that based on electrospinning technique and simultaneous electrospray was proposed to anchor TiO2 (P25) nanoparticles on the surface of rice straw-derived cellulose acetate (CA) nanofiber, a series of EE-CA/P25 nanofibrous membranes with different P25 dosage were successfully fabricated, which were characterized in terms of SEM, TEM, FI-IR, XRD, DRS, PL, UV–vis and 3D-EMMs, etc. Results confirmed that P25 nanoparticles were anchored on the surface of CA nanofiber. For different organic dyes of Methylene blue (MB), Rhodamine B (RhB) and Methyl orange (MO), EE-CA/P25(0.05) nanofibrous membrane toward MB dye showed the best photocatalytic degradation efficiency of 99.13 % after 30 min of light exposure. For the different antibiotics of Tetracycline (TC), Ciprofloxacin (CIP) and Sulfamethoxazole (SMX), EE-CA/P25(0.05) exhibited the best photocatalytic degradation efficiency of 83.59 % for TC after 30 min of light exposure. Moreover, EE-CA/P25(0.05) exhibited a good antimicrobial efficiency of 98.42 % for E. coli, and maintained 97.49 % after 5 cycles. The reactive radical trapping experiments revealed that h+, •O2−, and •OH participated in the reaction, and h+ and •O2− played a major role in the photocatalytic degradation process. Moreover, EE-CA/P25(0.05) flexible membrane was easy to recycle and transform rice straw waste into treasure.

Edible Spoon and Edible Straw: Solusi Cerdik dalam Mengurangi Sampah Plastik di Jombang, Jawa Timur

Plastic is a polymer compound whose main constituent elements are carbon and hydrogen. Because it is difficult to decompose in nature, plastic is the biggest contributor to waste which causes damage to the natural balance. Based on data from the National Waste Management Information System (2023), Plastic waste is the second most common type of waste after food waste, as many as 41.1%. The solution to banning the use of plastic spoons and straws has been found by creating environmentally friendly spoons and straws that are edible and biodegradable. This biodegradable (Edible Spoon) uses wheat flour as a base so it is safe for consumption. Edible and biodegradable straws (Edible Straw) are also made from natural ingredients, namely cassava flour (mocaf) and cornstarch. The method used to produce Edible Straw is the fruit peel method. The method used to produce Edible Straw is the fruit peel method. This method is used to make Edible Straw dough from a mixture of dough and fruit which is mashed into a thin sheet resembling skin. This community service was carried out by STIKES PEMKBAB Jombang students with the aim of reducing the amount of plastic waste, especially plastic spoon and straw waste in Jombang.

Transforming agricultural straw waste into functional nanofibers via electrospinning: A sustainable approach

Agricultural waste straw is produced in large quantities annually, particularly in regions with high crop yields, such as rice, wheat and corn.The resource utilization of straw plays an important role in environmental protection, resource utilization, partial replacement of fossil energy and promoting agricultural carbon neutrality. Moreover, it's well known that electrospinning technology plays a vital role in enabling the conversion of straw-derived cellulose, lignin, hemicellulose and derivatives into high-value nanofiber materials. In this perspective article, we mainly focus on the separation of components and high-value conversion of agricultural waste straw. Specifically, the separation methods of agricultural waste straw components, the spinnability of cellulose, lignin, hemicellulose and derivatives, and the fabrication of straw-derivated functional electrospinning materials were introduced in detail, and these electrospinning fiber material are widely used in the fields of carbon fibers, environmental adsorption, energy storage, and biomedical materials, which provides a new perspective and strategy reference for the comprehensive utilization of straw biomass resources.

A Newly Bio-Based Material for the Construction Industry Using Gypsum Binder and Rice Straw Waste (Oryza sativa)

Construction is one of the economic sectors with the greatest influence on climate change. In addition to working procedures, the primary carbon footprint is attributed to the choice of materials and the energy required for their manufacturing. The underlying idea of this study is to minimize the effects and offer new solutions to emerging problems in the quest for materials that can be deemed as natural, such as gypsum (calcium sulphate dihydrate) and rice straw (Oryza sativa). The acquisition of these materials involves a lower carbon footprint compared to the conventional materials. It is well known since ancient times that gypsum and cereal straw can be used in construction, with numerous examples still available. Cereal straw is one of the oldest construction materials, traditionally combined with earth and occasionally with certain binders, with it continuing to be employed in construction in many countries to this day. This work showcases the feasibility of producing stable prefabricated elements from straw waste with construction gypsum, addressing a significant environmental concern posed by the alternative of having to burn such materials. In this study, for the proposed bio-based material, specific tests, such as thermal conductivity, flexural and compressive strength, and fire resistance, were carried out to evaluate the principal physical and mechanical characteristics for different compositions of water, gypsum, and straw fiber samples. The results highlighted the good performance of the proposed materials in order to spread their use in the green building industry. The addition of straw fibers improved, in different ways, some important physical characteristics of these components so as to diminish environmental pollution and to obtain better material performance. The tests highlighted the different behaviors of the proposed material with respect to the different cuts of the straw and as well as the water/gypsum ratio; this is not very well understood and probably depends on the micro structure of the straw fibers. The blocks with raw straw showed a significant improvement in the breaking mechanism (1775.42 N) compared to the blocks with cut straw (712.26 N) when subjected to bending tests, and their performance in compression tests was also acceptable. Additionally, a very interesting reduction in thermal conductivity was achieved by incorporating rice straw (0.233 W/mK), and high fire exposure times were obtained, with gypsum preventing the spread of ignition in any type of fiber.

High temperature pyrolysis of sewage sludge: Synergistic effects of co-pyrolysis with rice straw and composite plastics wastes

The synergistic effect of co-pyrolysis for the mixtures of sewage sludge (SS), rice straw (RS) and composite plastic wastes (PE&PP) has been investigated with the aim of high gas yields and hydrogen generation. In this context, the applicability of high temperature pyrolysis technology was evaluated at both rotary type batch reactor and rotating screw type continuous reactor operating under the industrially relevant conditions. Gas yields have been improved at increasing the operating temperatures up to 850 °C. The gas yield of 75.06 % with its H2 portion of 32.35 % has been achieved as the best results for continuous pyrolysis unit at pilot scale. Secondary reactions such as steam de-alkylation, steam cracking, water gas shift and so on were regarded as being responsible for the high gas yields when the primary products of pyrolysis, i.e. condensable vapors, were much exposed to the hot zones inside the reactor. The dehydration of organic components involving the loss of water may supply steam to create a reactive pyrolysis atmosphere. While the pyrolysis of sewage sludge and rice straw favors CO and CO2 formation due to the high oxygen contents of these feedstocks, more methane and light olefins were produced when the plastics were added to the feedstock blends. This was ascribed to the initially generated radicals from the decomposition of sewage sludge and/or rice straw that might promote the scission reactions of plastics towards volatiles. It was shown that high temperature pyrolysis can be applied to a variety of organic wastes such as rice straw, sewage sludge and waste plastics. Conversion of wastes to hydrogen fosters the circular economy by putting the disposal costs down and creates a new route on renewable hydrogen generation.

Efficient Extraction and Analysis of Wheat Straw Lignin by Response Surface Methodology

To enhance the high-value utilization of straw waste and achieve efficient lignin extraction, wheat straw was selected as the feedstock for investigating the effects of reaction temperature, reaction time, solid–liquid ratio, and formic acid concentration on lignin yield using a formic acid/acetic acid solvent system. A single-factor experimental design was initially employed, followed by optimization using the response surface methodology. Additionally, a kinetic model was developed to describe lignin extraction kinetics in the formic acid/acetic acid system. The structural characteristics and thermal stability of the extracted lignin were analyzed via FTIR, UV spectroscopy, and TGA. The findings indicate that increasing reaction temperature, reaction time, solid–liquid ratio, and formic acid content all significantly enhanced lignin extraction yield from wheat straw, with the primary influencing factors being reaction temperature &gt; solid–liquid ratio &gt; reaction time &gt; formic acid content. The optimal extraction conditions were identified at a reaction temperature of 90 °C, a reaction time of 3.5 h, a solid–liquid ratio of 1:16.5, and a formic acid content of 86.2 wt.%, yielding a lignin content of 79.83%. The analytical results demonstrated that the extracted lignin preserved the structural integrity of the original lignin and exhibited good thermal stability.