In previous experiments the effects of blending coal with relatively high-ash/low energy content cattle

(plenum). The steam is generated by a steam generator built with a cylindrical 4-inch internal diameter vessel heated by a (1.2 kW) type tape heating element rolled around of the vessel with variable power output (0.1 to 1.2 kW); thus, the steam production rate can be controlled from 0.1 to 1.5 kg/h by changing the power supplied to the heater element. The sampling unit is composed of two condensers cooled with ice-cold water (0°C) to condense out the tar and the H2O in the products and a filter system to retain the particulate material. The temperature of the bed is measured every 60 seconds using K-type thermocouples (Cr-Al) placed at 8 locations along the gasifier axis. The gas samples are analyzed by a mass spectrometer (MS) continuously at real time (Gordillo, 2009).

3.13.1 Experimentation

The gasification experiments were performed for the following cases:

(a) Base case

• Bed height at 17 cm (~6%")

• Fuel: low ash separated solids dairy biomass (LA-PC-sepsol-DB).

• Particulate size, dp = ~6.25 cm (1/4") for DB and ~3 mm (~1/8") for coal

• Fuel flow rate 1 kg/h (2.2046 lbm/h)

• Air flow ~ 1.13 normal m3/h (40 SCFH) at 298 K (536 R)

• Steam flow rate at 0.3 kg/h (~0.66 lb/h)

• Equivalence ratio (ER) at 3.18

• Steam to fuel ratio (S:F) at 0.68

(b) Parametric cases

• Fuel: LA-PC-Sepsol-DB, Coal-LA-PC-Sepsol-DB blend (90% LA-PC-Spsol-DB, 10% coal), and Ash — LA-PC-Sepsol-DB blend (90% LA-PC-Sepsol-DB, 10% ash)

• Air flow between 0.57 and 2.26 normal m3/h (20 and 80 SCFH) at 298 K (536.4 R)

• Steam flow rate between 0.18 and 0.5 kg/h (0.4 and 1.1 lb/h) at 373 K (671.4 R)

• Equivalence ratio (ER) between 1.59 and 6.36

• Steam to fuel ratio (S:F) between 0.35 and 0.8

• Experiments with (i) DB-coal blends (90% DB-10% Coal) (ii) DB-ash blends (90% DB — 10% ash) were used in order to determine catalytic effect if any on gasification.