Investigation of Biomass Ash Properties for Their Utilization Assesment

Abstract

Ash is a mineral waste group, which quantity increases on a global scale and now it has achieved hundreds of millions of tons, and as they are an integral part of the any solid fuel, including biomass the production rate will continue. At the same time ash, due to their nature and composition is a unique material that can be valuable technogenic resource. The paper studies the wood ash physical properties (density, porosity, specific free surface) composition and the metal adsorption ability. It was found that wood ash contains a significant percentage of metals in the mobile phase, which dissolve in the water and thus are able to spread into the surrounding soil. The study established a high adsorption activity of ash (95-99%) to the metals. It was found that the adsorption capacity of the ash is possible to increase with the activation of the ash particle surfaces and changing the pore structure.

Water-Soluble Fractions of Biomass and Biomass Ash and Their Significance for Biofuel Application

“…On the other hand, it was identified that TEs such as B, Li, Mo, Rb, Sr, Y, U, Cr, Ni, V, Pb, and Zn associate preferably with the water-soluble fractions in BAs produced from the present eight biomasses . Most of these TEs plus Br, Ba, Be, Co, As, Cd, Cu, Hg, Sb, Se, and Sn reveal also significant water leaching from other BAs (Table and reference data − ). Additionally, it was identified that different TEs correlate positively with the most water-soluble chlorides (B, Sr, U, Co, and V) and sulfates (Mo, Rb, Sr, U, Co, Cr, Ni, V, and Cu), and normally with the less water-soluble phosphates, carbonates, and oxyhydroxides (B, Ba, Cs, Hf, Li, Nb, rare-earth elements, Rb, Sr, Th, U, Y, Zr, Co, Bi, Cu, Ga, Pb, Sn, and Zn) in the present eight BAs .…”

“…The reference data for the electrical conductivity of water leachates (19 samples) from woody, straw, and cereal BAs varies between 3.0 and 49.5 mS cm ‑1 (mean, 20.2). ,,,,, It can be seen that these values are much higher than those for biomass. The explanation of this observation is similar to that for pH in biomass and BA.…”

“…The water-soluble elements in various BAs have also been studied (see refs , , − , , , and − ). The reference data show (Table ) that the mobile elements (based on mean contents) leached from BAs and generated dominantly from woody and straw biomasses are mainly Cl, S, K, Na, Sr, Mn, and Ni and, to a lesser extent, Si, Li, Mo, Co, Cr, Cd, and Zn, and some Br, P, Al, Ba, Ca, Mg, Fe, Cu, Hg, Pb, Sb, and Se (see refs , , , , , − , and − ).…”

“…The reference data for pH values of numerous BA water leachates (103 samples) generated dominantly from woody, herbaceous, and agricultural biomasses vary in the range of 4.5–13.5 (mean, 11.3) [see refs , , , , − , , , − , and − ). These solutions have acidic to highly alkaline character; however, the BA leachates are mostly alkaline, whereas the low pH values are characteristic of BAs enriched in unburnt char probably due to the occurrence of some residual organic acids.…”

Physico-technical approach to design of composites from mineral and polymer technogenic resources

“…For example, Finland produce annually 6.105 tons of ash, Sweden 8.105 tons, USA-3.106 tons, China 2.106 tons. [31] The aim was to find out in principle the possibility of creating a monolithic composite containing the matrix-forming fraction -thermoplastic polymer as a binder adhesive and substrate -a mineral filler components -ash or clay. Ash and especially wood ash characteristics were investigated during last 3 years [31,32].…”