The quantity of wastes produced depend of factors as: the number of inhabitant in the city, urbanization rate, consumption habits, cultural practices to handle of wastes, the income, the application of technology and industrial development. According to the information reported by the "Superintendencia de Servicios Publicos Domiciliarios" by 2008, see [4], in Colombia were generated daily 25.079 tons of urban solids wastes, 10 million of tons/year, which 77% were domestics (19.310,8 ton); 15% Industrials (3.761,9) and 8% others (2.006,3 ton). In the
country, the management of wastes is focused to the final disposal in landfill; only 2,4% is dedicated to recycle and valorization [1].

In the country, the solid wastes are mainly composed of organic material (65%), followed by the plastics (14%), paper and cardboard (5%), glass (4%), other components with minor participation.

Table 2. Composition of solids wastes in Colombia

In Colombia the major quantity of solid wastes generated are collected and treated by municipal companies (waste from domestic activities, commercials and industrials); however in some regions the problem of wastes solids is very important as the final disposition is made with little control, generating environmental pollution. The production of wastes (kg/habitant/ day) is approximately 0,5 kg/habitant/day, oscillating between 1 kg/habitant/day for the big

cities until 0,2 kg/habitant/day in the small towns [15]. The "Superintendencia de Servicios

Publicos Domidlia/ios" pssbiishedby 2002 a /ludy absa^/ tha finaldisnosition of tirosolids wastes in t.086 aihes. Tlso tedmologieo тоаеОгарикпІаге^итрвіІе and oseb indnoration (52%), thentandfin (30 %/ a/sci Sinrsilyi t;lii<i ii.^e it:i <]o:^qt.::>is^t:i|^i. s|., incmeration and other. [1896:, ]b[.

Source: [6].

There are two options to solve the problems generated by urban solid wastes which can be applied simultaneously to reach an optimum result:

• The first option according to the National Politics of Solid Wastes is give priority to integral management of solids wastes, focusing the operations management in the reuse and valorization of different materials that integrate the urban solid wastes.

• The second option is to take the wastes and give them an adequate final disposal in landfill operated technically.

The biomass in Colombia has calorific values between 4,384 kcal / kg for stems of coffee and 1,800 kcal / kg for banana rachis [7]. These values are comparable with reports from other countries as China where biomass from agricultural and forest activities have values between 3,827 to 4,784 kcal / kg [8]. In Argentina the lignocellulose biomass has values between 3,000 — 3,500 Kcal / kg and the municipal wastes between 2,000 and 2,500 Kcal / kg [9].

2.1. Colombian normativity about solid wastes

The Colombian normativity related to management of organics solids wastes began with the code of renewable natural sources (decree 2811 of 1974) and were implemented the followed norms:

• Decree 2104 of 1983: management of solids wastes.

• Resolution 2309 of 1986: special solids wastes.

• Law 142 of 1994: Law of public services.

• Decree 605 of 1996: Indications for an adequate cleaning service, from the generation, storage, collection, transport, to final disposition.

• Committee Technical ICONTEC 000019 about environmental management of solids wastes.

• Decree 1716 of August 2002 of "Ministerio de Desarrollo Economico" (In English: Economic Development Ministry) by mean the law 142 of 1994, law 632 of 2000 and the law 689 of 2001, related to the cleaning public service, the law 2811 of 1974 and the law 99 of 1993. The article 8 related to the program for the integral management of solids wastes, which should be realized by the cities in a maximum time of 2 years [10].