Valorization of Sida (Sida hermaphrodita) biomass for multiple energy purposes

Abstract

The performance and biomass yield of the perennial energy plant Sida hermaphrodita (hereafter referred to as Sida) as a feedstock for biogas and solid fuel was evaluated throughout one entire growing period at agricultural field conditions. A Sida plant development code was established to allow comparison of the plant growth stages and biomass composition. Four scenarios were evaluated to determine the use of Sida biomass with regard to plant development and harvest time: (i) one harvest for solid fuel only; (ii) one harvest for biogas production only; (iii) one harvest for biogas production, followed by a harvest of the regrown biomass for solid fuel; and (iv) two consecutive harvests for biogas production. To determine Sida's value as a feedstock for combustion, we assessed the caloric value, the ash quality, and melting point with regard to DIN EN ISO norms. The results showed highest total dry biomass yields of max. 25 t ha À1, whereas the highest dry matter of 70% to 80% was obtained at the end of the growing period. Scenario (i) clearly indicated the highest energy recovery, accounting for 439 288 MJ ha À1 ; the energy recovery of the four scenarios from highest to lowest followed this order: (i) ≫ (iii) ≫ (iv) > (ii). Analysis of the Sida ashes showed a high melting point of >1500°C, associated with a net calorific value of 16.5-17.2 MJ kg À1 . All prerequisites for DIN EN ISO norms were achieved, indicating Sida's advantage as a solid energy carrier without any post-treatment after harvesting. Cell wall analysis of the stems showed a constant lignin content after sampling week 16 (July), whereas cellulose had already reached a plateau in sampling week 4 (April). The results highlight Sida as a promising woody, perennial plant, providing biomass for flexible and multipurpose energy applications.

Anaerobic Co-digestion of the Energy Crop Sida hermaphrodita and Microalgae Biomass for Enhanced Biogas Production

“…Because no fertilizers were used for Sida cultivation, low nitrogen concentration in harvested biomass could be attributed to nitrogen limitation in soil . Jablonowski et al (2016) showed that the first cut of Sida in June at a development stage of BBCH-Sida 55 displayed a TS content of 20%, while in our study it was 37.43%. However, silaging contributes to increasing VS and TS contents over time.…”

“…It was similar to our results of biogas and methane production of 381.39 and 166.61 mL/g VS, respectively. Jablonowski et al (2016) achieved a biogas yield of 419.5 L/kg VS with methane concentration of 53.5% from the silage of Sida at the development stage of BBCH-Sida 55. In turn, the yield of methane production from the microalgae biomass may reach 240-307 mL/g VS for Chlorella vulgaris and 210-261 mL/g VS for Scenedesmus sp.…”

Virginia mallow (Sida hermaphrodita (L.) Rusby) as perennial multipurpose crop: biomass yields, energetic valorization, utilization potentials, and management perspectives

“…When used as solid fuel, parameters often determined are the higher heating value (HHV) and the lower heating value (LHV). In ten studies considered in this review, the HHV of Sida ranked between 16.5 and 19.5 MJ kg −1 dry matter (dm in the following) at an average of 18.4 ± 0.9 MJ kg −1 dm; the LHV between 14.0 and 17.2 MJ kg −1 dm at an average of 16.1 ± 1.2 MJ kg −1 dm (Borkowska et al ., , ; Wróblewska et al ., ; Smoliński et al ., ; Szyszlak‐Barglowicz et al ., ; Stolarski et al ., , ; Franzaring et al ., ; Tworkowski et al ., ; Siaudinis et al ., ; Jablonowski et al ., ). Whilst the HHV of Sida biomass appeared to be rather constant from November until April in one study, the LHV increased from 9.7 to 15.0 MJ kg −1 within this time span (Stolarski et al ., ), presumably owing to the changing water content of the biomass.…”

“…It even reached 88.1 % in another study, in which, however, the time of harvest was not given (Michalska et al ., ). In accordance with these findings, the contents of cellulose and lignin in the stems remained rather stable from June until December, whilst they increased during that time in the leaves (Jablonowski et al ., ).…”

Spelt (Triticum spelta) and Emmer (T. dicoccon) Chaff Used as a Renewable Source of Energy

“…The results were used to calculate the lower calorific value (LCV) using Eq. 1 (Brlek et al 2012;Jablonowski et al 2016…”