**4.2. Composting procedures**

The compost should to have an adequate degree of stabilization (maturity); and qualified amendments and nutritional properties.

The quality of the compost is function of the following factors:


The composting of selected organic substances has to be considered as a recovery system for the production of high quality organic amendments to use for the agricultural purpose able to replace, even though partially, the manure in the extensive agriculture, the chemical fertilizers in the intensive crops and the peat in nursery.

The ACT phase, in relationship to the characteristics of the treated mixture, can happen in piles on open air, or confined in more complex systems (bioreactors) with forced airing, with or without overturns. During this phase must be checked the temperature, moisture, pH and oxygen. The duration of this phase should be enough to guarantee the attainment of an adequate Respiration Index (I.R.) of biomass, to be test with the IPLA (Institute of Plants, Wood and Environment) method (IPLA, 1992). This duration corresponds to about 21 days of treatment, in the case of stabilization in overturned piles and about 14-16 days in the case of bioreactors.

186 Olive Germplasm – The Olive Cultivation, Table Olive and Olive Oil Industry in Italy

from the matrixes of the Green composted Amendment;

amendment or Mixed composted amendment.

Legislative Decree 152/99, for landfill.

**4.2. Composting procedures** 

components;

amendments and nutritional properties.

the oxygenation of mixture;





The compost should to have an adequate degree of stabilization (maturity); and qualified



The composting of selected organic substances has to be considered as a recovery system for the production of high quality organic amendments to use for the agricultural purpose able to replace, even though partially, the manure in the extensive agriculture, the chemical

The ACT phase, in relationship to the characteristics of the treated mixture, can happen in piles on open air, or confined in more complex systems (bioreactors) with forced airing, with or without overturns. During this phase must be checked the temperature, moisture, pH and oxygen. The duration of this phase should be enough to guarantee the attainment of an

a specific authorization, released from the local administrations.

The quality of the compost is function of the following factors:


fertilizers in the intensive crops and the peat in nursery.

For the realization and the management of the composting installation can be followed:

The curing phase is always carried out in piles and require a lower amount of oxygen and overturn in comparison to the ACT phase.

The biomasses to be composted must be previously grinded and mixed to optimize the characteristics of the matrix (C/N ratio, porosity, moisture, pH). A good starting matrix for the production of a Quality Composted Amendment (ACQ), has to have a moisture among 45 and 65%, C/N among 20 and 30, with at least a 30% in weight of lignocelluloses material. The ACQ can be commercialized to the senses of the Law 748/84, also in mix with other fertilizers, according to the same law prescriptions, as reported in Table 5. This material could be used in the agricultural activities or similar (maintenance of the public or private green, biofilters, etc.).


**Table 5.** Limits of acceptability for the Quality Composted Amendment (ACQ), conforming to Annex 1C of the Law 748/84, as modified by the D.M. of 27.03.1998.

The composting process can also carried out with low-tech approaches and extreme operational simplification, excluding the forced airing and effecting the biomass overturns using machineries already in endowment to the farm (choppers, shovel loader, wagon mixers).

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matrixes well structured and homogeneous, with at least 40 - 50% in weight of lignocelluloses bulking, to avoid the compaction of the mass, and moisture less than 65%.

In the dynamic systems can be processed very moisture matrixes (> 65%) and with less than

The forced airing of the biomass is an important factor of optimization of the process particularly for the treatment of low consistence and higher fermentability biomasses. For



proportionally involve lesser thermometric levels of the biomass (Higgins, 1982).

closed systems they are: Biocontainer; Dynamic trenches; Dynamic basins; Silos.

The different processing systems, classified according to the installations or the operational methodology, can be associate to one or more of following categories. Typically, among the open systems are included: Aired static pile; Overturned pile; Short pile. While, among the

The aired static pile constitute a system of relative technological simplicity. It was developed in America as "Beltsville system ", with the purpose to have a simple system of the wastes biomasses bioconversion to the farmers for agronomic reuse. In his different variations, it shapes as an open, static and aired system (Willson et al., 1980). Typically it foresees the disposition of the biomass in pile, with forced airing in aspiration below the pile and dispatch of the exhausted air to a compost-made biofilter. On the pile surface a layer of mature compost is placed, with not permeable and filtering actions. As static system, it requires of a high percentage of structural lignocelluloses bulking, and of a relatively low moisture of the starting matrix. It also requires a appropriate homogenization pre-

the optimization of the forced airing it is necessary to calculate and monitoring:

necessary appropriate systems of control and remoisten.

30% in weight of lignocelluloses bulking.

*4.3.3. Systems "aired" and "not aired"* 

*4.3.4. Aired static pile* 
