High-Grade Chemicals and Biofuels Produced from Marginal Lands Using an Integrated Approach of Alcoholic Fermentation and Pyrolysis of Sweet Sorghum Biomass Residues

Abstract

New global directions align agricultural land resources towards food production; therefore, marginal lands could provide opportunities for second-generation energy crops, assuming that in the difficult conditions of plant development, productivity can be maintained at relatively high levels. Sustainable bioenergy production on marginal lands represents an ambitious objective, offering high-quality biofuels without competing with the agri-food industry, since it allows successful feedstock production to be performed on unmanaged areas. However, marginal land feedstock production generally shows several agronomic, techno-economic, and methodological challenges, leading to decreases in the obtained quantities of biomass and profitability. Sweet Sorghum is a technical plant that has the needed qualities to produce large amounts of biofuels on marginal lands. It is a high biomass- and sugar-yielding crop, characterized by a high photosynthetic efficiency and low fertilizer requirement, is resistant to drought, and adapts well to different climate areas. Marginal lands and contaminated soils provide a favorable development environment for plants such as sweet sorghum; however, in-depth research studies on biomass productivity must be carried out, as well as advanced quality evaluation of the products, in order to develop combined technologies that use resources efficiently. The present study starts with a comparative evaluation of two sweet sorghum crops established on both marginal and regular lands, assessing plant development characteristics and juice production, and an evaluation of bioethanol generation potential. The vegetal wastes resulting from the processing were treated by pyrolysis, with the aim of maximizing the productivity of high-quality liquid biofuels and chemicals. The charcoal obtained in the thermal processes was considered as an amendment of the soil so that marginal land quality could be improved over time.

Slow Pyrolysis of Ulva lactuca (Chlorophyta) for Sustainable Production of Bio-Oil and Biochar

“…Thermochemical processes of gasification, torrefaction, and pyrolysis are considered favorable due to them being more cost-effective and efficient [4][5][6]. Pyrolysis is a thermochemical process that has received much interest in recent years as a cost-effective and energy-efficient process for biomass conversion to biofuels and valuable chemicals [7]. Principally, pyrolysis is conducted by biomass conversion at a temperature between 300 and 600 • C in the absence of oxygen, generating three main products, i.e., bio-oil, biochar, and syngas [8].…”

Decentralized Processing Performance of Fruit and Vegetable Waste Discarded from Retail, Using an Automated Thermophilic Composting Technology

“…The centralized processing is the most used municipal organic waste management system. In this approach, a regional operator collects and processes fresh waste on a large specific area using simple and expensive techniques and producing odors, leachate, and anaerobic degradation of organic matter [10,11]. Centralized municipal waste management systems may lead to several operating difficulties and challenging situations.…”

“…The temperature inside the equipment is rapidly increased with a ceramic heating system (9), which has the role of creating the needed conditions for thermophilic composting and to dehydratase the fruits and vegetables, allowing processing of a larger volume of organic material. The excess air moisture is being absorbed by an air pump (10), which is provided with gas analyzer (11) and a deodorizing filter (12). The sensors associated with the reactor are used to detect the temperature of the heater ( 13), detect the temperature of the material being processed ( 14), a sensor monitors air humidity (15), and the volume of material inside the composting equipment (16).…”

Pyrolysis characteristics, kinetics, and biochar of fermented pine sawdust–based waste

“…Currently, the major conversion technologies for biomass treatment are incineration, pyrolysis (Feng et al 2022), hydrothermal (Wang et al 2021), fermentation composting, fine chemicals production (Nenciu et al 2021). The incineration method requires high operation cost and energy consumption on flue gas treatment.…”