Mass-Scale Algal Biomass Production Using Algal Biofilm Reactor and Conversion to Energy and Chemical Precursors by Hydropyrolysis

Abstract

A pilot-scale algal biofilm reactor (P-ABR) was assessed for its potential to provide a continuous supply of high volume algal biomass to be utilized as feedstock for hydropyrolysis. The half-year long performance assessment showed significantly high productivity of 15−20 g m −2 d −1 with uniform biochemical composition. Hydropyrolysis (HyPy) using ZSM-5 was used to convert and partition ABR-grown algal biomass components into energy-rich biocrude (HyPyO), nutrient-rich aqueous condensate (HyPyA), carbon-rich solid residue (HyPyS), and gases. The effect of temperature on yield and composition of different HyPy products was quantified in terms of carbon and nitrogen recovery. The maximum yield of biocrude was 31% at 200 °C and decreased to 18% with an increase in temperature up to 300 °C. The influence of temperature on recovery of nitrogen showed preferential accumulation of nitrogen in the aqueous phase with increasing temperature. The highest carbon recovered was 41% in the form of biocrude (HyPyO) at 200 °C followed by 31% in HyPyA at 300 °C. In the context of energy and nutrient recovery potential of each of the HyPy products, applications of different fractions was explored for development of a sustainable algal biorefinery.

Catalytic hydropyrolysis of biomass using supported CoMo catalysts – Effect of metal loading and support acidity

“…However, it should be noted that too high acidity can also lead to polymerization and coke formation [15]. Several other research groups have also used H-ZSM-5 in catalytic hydropyrolysis both as a catalyst [18][19][20][21][22][23] and as support [19][20][21]24].…”

New insights into the effect of pressure on catalytic hydropyrolysis of biomass

“…Several groups have investigated catalytic hydropyrolysis using Pyroprobe reactors and H-ZSM-5, often impregnated with Ni [9][10][11][12][13][14][15]. Melligan et al [15] investigated the effect of hydrogen pressure at 600 °C using a Ni/H-ZSM-5 catalyst and found that increasing the hydrogen pressure increased the higher heating value (HHV) of the products, due to an increased degree of deoxygenation.…”

A perspective on catalytic hydropyrolysis of biomass

“…This work focuses on results obtained in (semi-)continuous bench scale and pilot plant reactors. Despite that several research groups have investigated catalytic hydropyrolysis in Pyroprobe reactors [34,[47][48][49][50][51][52], these results are generally not discussed in this work due to their relatively poor comparability with results obtained from (semi-)continuous reactors.…”