R. Arjona

The CO2 gasification kinetics of olive residue

Abstract Orujillo , sometimes called wood matter from pressed oil-stone (WPOS) is a residue from the olive oil mill industry. The generation of this biomass residue is concentrated in small areas allowing its use as fuel for medium size gasification and combustion plants. Rates of gasification of WPOS char were measured in a TGA at various temperatures (800–850–875–900–950°C), CO 2 partial pressures (0.20–0.35– 0.50 bar ) and CO partial pressures (0.0– 0.20 bar ). The experiments were carried out with a monolayer bed of very fine particles well exposed to the gas so as to minimise mass and heat transfer resistances. Two kinetic models, the n th order model and Langmuir–Hinshelwood model, have been used to fit with the reactivity data. For pure CO 2 experiments the kinetic parameters of n th order model were E=133 kJ/mol and n =0.43. The Langmuir–Hinshelwood kinetic model clearly describes the observed CO inhibition effect on the CO 2 gasification.

The drying of alpeorujo, a waste product of the olive oil mill industry

Alpeorujo is a waste product of the olive oil mill industry that still has a significant oil content. Before extracting the remaining oil with hexane, the moisture content of the wet waste product has to be reduced from approximately 65% to about 8%. To develop standards for dryer design and operation, an extensive study was carried out at laboratory scale. A drying tunnel was built to calculate drying curves, volatile emissions, ignition temperatures, and solids degradation at high temperatures while drying under several different operating conditions. The results of this experimental work allowed us to develop a useful drying model for designing new dryers and for assessing the behaviour of existing ones.

Modelling and PID Control of a Rotary Dryer

This paper describes the modelling and the control strategies of a drying process. The plant uses a co-current rotary dryer to evaporate moisture of a waste product generated by olive-oil mills, called alpeorujo or two phase cake. The paper shows the development of a model based upon first principles combined with experimental results. A control strategy has been tested under simulation based on H ∞ controllers for the outer loop in this process.