Valorisation of agricultural biomass-ash with CO2

Abstract

This work is part of a study of different types of plant-based biomass to elucidate their capacity for valorisation via a managed carbonation step involving gaseous carbon dioxide (co 2). the perspectives for broader biomass waste valorisation was reviewed, followed by a proposed closed-loop process for the valorisation of wood in earlier works. the present work newly focusses on combining agricultural biomass with mineralised co 2. Here, the reactivity of selected agricultural biomass ashes with co 2 and their ability to be bound by mineralised carbonate in a hardened product is examined. three categories of agricultural biomass residues, including shell, fibre and soft peel, were incinerated at 900 ± 25 °C. The biomass ashes were moistened (10% w/w) and moulded into cylindrical samples and exposed to 100% CO 2 gas at 50% RH for 24 h, during which they cemented into hardened monolithic products. the calcia in ashes formed a negative relationship with ash yield and the microstructure of the carbonate-cementing phase was distinct and related to the particular biomass feedstock. this work shows that in common with woody biomass residues, carbonated agricultural biomass ash-based monoliths have potential as novel low-carbon construction products. This paper discusses environmental issues that are of relevance to the sustainable use of resources and protection of the environment. By re-using abundantly available agricultural biomass residues, and by reducing the amount of cement used in construction and their associated carbon emissions, significant potential sustainability gains can be realised. In consideration of this, a low carbon management option for biomass residues is proposed. Agricultural activities generate huge volumes of biomass residues, with crop derived waste accounting for 94% of global biomass production 1. These include cereals (wheat, rice, maize, and barley), sugarcane, soybean, and some oil crops, fruits, vegetables, roots and tubers, and sugar beet 1. These residues are expected to increase as the world's population exceeds 11 Billion by 2,100 2. It is estimated that globally 140 Gt of agricultural residues are generated each year 3,4. According to Lal (2019) 5 , the total annual amount of crop residue produced globally is estimated at 2.8 Gt for cereal crops, 3.1 Gt for 17 major cereals and legumes, and 3.8 Gt for 27 common food crops. The IEA CCC (2015) 6 reports the global resource for unexploited cereal crop residues amounts to 517 Mt. The FAO (2002) 7 projects that from 1999 to 2030, the agricultural sector of developing countries will increase by 13% or 120 M ha. Predictions for global cereal yield suggest an increase in the range 0.9% per annum over the period 2005/2007-2050, continuing a trend of long-term declining yield growth (20 y average yield increase declined from ~ 3% pa in 1982, to ~ 1% by 2005) 8,9. The intensification of agricultural and increased crop yield (producing more per unit of land) will undoubtedly raise crop residue production 10. A positive correlation exists betw...

Market prospects for biochar production and application in California

“…Torrefaction or mild pyrolysis occurs in the range of 200-350 °C often under atmospheric pressure in the partial or complete absence of oxygen, and produces a solid product commonly referred to as 'torrefied biomass' , but in some cases (e.g., severe torrefaction (270-320 °C, residence time > 30 min), oxidative torrefaction), 26 'biochar' . [27][28][29][30] Some other processes like hydrothermal liquefaction, 31 carbonation or gasification 31,32 may also be employed to produce biochar. Each of these processes may involve certain pre-processing steps to improve the overall performance.…”

Mites as a natural weapon against soil-borne fungal diseases

“…5b), and we found that coconut husks (Fig. 6a), an agricultural waste of porous structure and abundant in developing countries 44,45 , could be a promising candidate.…”

“…In addition, our method might have a co-benefit for climate change mitigation. First, the method involved the reuse of coconut husks and agricultural wastes found in abundance in developing countries 44,53 , and therefore might reduce the CO2 emissions from incineration disposal (or burning by householders) of coconut husks 45 . Second, our results showed that the application of coconut husks could also reduce the soil-emitted N2O (Fig.…”

“…5b). In contrast, although coconut husks are organic matter, they are unlikely to affect mites by providing food sources because they are mainly composed of cellulose and lignin, which can be neither directly digested by mites 46,47 nor rapidly decomposed in soil 45,48 .…”

Mechanical and Thermomechanical Properties of Clay-Cowpea (Vigna Unguiculata Walp.) Husks Polyester Bio-Composite for Building Applications

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