Table 1 Summary of the reactor configurations and experimental conditions for the four pretreatment reactor systems used in this study

Operating mode

Batch

Batch

Batch

Continuous

Sample amount (kg, dry basis)

0.003

0.07–0.10

0.25

10–25 kg/h

Operational capacity (kg/day)

0.03

0.7

0.8

600

Biomass impregnation

In situ

Ex situ

Ex situ

Ex situ

Heating

Oven

Steam injection

Steam injection

Steam injection

Minimum residence time (min)

4

4

1

10

Solids loading (\(\%\))

10

25

25–30

30

Conditions per day\(^\mathrm{a}\)

9

9

8

4

Operator hours per condition\(^\mathrm{b}\)

0.5

2

2

6

Mechanical shearing

–

–

X

X

Rapid decompression

–

–

X

X