"Chemical-physical process fertilizer production from organic waste and production plant"

Technical field of invention

The present invention regards a chemical-physical process fertilizer production from organic waste, catalyzed by a catalyst composed by salts and organometallic complexes of transition metals. State of the art

During the last years the problems of reusing the organic material contained in urban or industrial wastes became extremely important for different reasons. First of all, it is necessary to eliminate the environmental troubles caused by the large mass of wastes produced every day in the industrial countries. In the same time the awareness is increased in order to be able to use the organic wastes and especially humid wastes to product good fertilizers for agriculture, mainly when such wastes are deprived of contaminators like heavy metals which represent dangerous contaminators for the soil. Up to nowadays the most widely used method for fertilizer production from organic wastes is that commonly defined "composting". Such method permits to obtain a fertilizer known as "compost", the term which indicates a material deriving from a particular process which permits the transformation of an organic mass. The present invention regards a chemical-physical process fertilizer production from organic waste, catalyzed by a catalyst composed by salts and organometallic complexes of transition metals in which the humid organic wastes, opportunely smashed in pieces of millimetrical dimensions, are shaked by means of opportune movement systems in presence of said catalyst up to the moment in which the water content present in the reacting mass becomes inferior to determined fractions of global mass. The invention regards also the production plant of said process characterized by the presence of at least: a) mills for the materials smashing; b) a feeding device of the reaction chambers which permits the balancing of different types of wastes so that the produced fertilizer obtains assigned chemical compositions; c) one or more than one reaction chambers in which the reacting mass can be opportunely shaked in order to favour the continuous mixing of the material and the fixing of the equal reaction conditions in the entire mass of reacting material; d) a sieve for the separation of plastic, glass or other undesirable materials with dimensions superior to those of produced fertilizer; e) devices for the heating and circulation of hot liquids acted to maintain the conditions of temperature settled for the best conduction of the processes; f) devices for the refrigeration and circulation of cold liquids acted to condense the water vapours eliminated during the drying process; g) traps for the reduction of gas emissions from the reaction environment; h) devices for gathering and bagging of produced fertilizer; i) wastes moving devices; 1) automation and process conditions control devices. The transformation of the initial instable organic substance in a more stable one which constitutes the compost takes place by means of a controlled process of biological aerobical decomposition which consists of three subsequent phases: the mesophil phase, the thermophil phase and the maturing phase, during which the three different bacterial, mycotic and actinomycetes species, in presence of protozoes participate actively to the transformations .

The main problems which limit the generalized application of this wastes organic fraction recycling methodology are linked first of all to the duration of the natural process which cannot be less than 3 months. Moreover, the installation of composting

plants requests rather extended surfaces situated over dense populated urban areas. It is also necessary to consider that the materials to be composted emit, especially in the mesophil phase, polluting gas substances which immediate consequence is the propagation of unpleasant smells. This constitutes a strong obstacle for the propagation of compost production plants close to the urban areas. For this reason, countries with high population density try to substitute this natural process with faster ones, where the inconveniences mentioned above have been eliminated.

The approach emerging nowadays is to set the processes in which the organic material deriving from the wastes is treated in a way that the chemical composts which compose it are reduced in much more simple molecules in comparison to the initial ones. The subsequent reduction of water content produces a stabilization of the material such that it does not emit unpleasant smells and can be conserved for long periods of time without the verification of bacterial fermentation phenomenon. The subsequent spreading of such material on the soil leads to its gradual usage as well as to its partial transformation in more complex substances used, in their turn, by the soil thanks to the microorganisms present in it. These transformation processes of original material in a natural fertilizer are much more rapid of natural bacterial composting because they can last only for a certain number of hours or at least for some day.

Numerous methods have been developed for the rapid production of fertilizers from organic wastes.

JP2003055078, 2003-02-26, Mabuchi Kosaku, describes a process in which the wastes are first sterilized by boiling under high pressure (15-25 atm.) and high temperature

(150-250 ⁰ C) and subjects subsequently to drying.

KR20010091641, 2001-10-23, Lee Moon Hyoung, describes a process which provides the first phase of aerobic fermentation of balanced in their composition wastes, and the subsequent drying of fermented material.

CN2003-01-08, Zhao Xianjin ; Xu Weijian; Sun Jinghu, describes a process which regards the production of a natural catalyst obtained by drying and the smashing of some natural materials like fruits peel, melon seeds, nuts shells.

JP5295376, 1993-11-09, Takahashi Hitoshi. In this patent the wastes (mostly, depuration muds and humid organic wastes) are mixed with peroxides of alcaline metals or with chlorides of alcaline metals. The ignition of the oxidant substances acts in a way that when the wastes are spread on the soil they decompose very rapidly.

In some processes the wastes are usually dehydrated under conditions of high temperature and pressure. The wastes stabilization is majorly operated by effect of high thermal conditions which are particularly elevated when the pressure is maintained high. The efficiency of chemical demolition of some organic chemical substances (protein, cellulose, amides etc.) under such conditions is rather low. As the subsequent processes of materials storage cannot certainly occur under sterile conditions and talcing into consideration that the humidity persists anyway in the final fertilizers they cannot be conserved for a long time because the fermentative processes owing to the presence of the bacteria in the environment could start. To obstacle such processes it is necessary to realize the processes of partial oxidation and a finer smashing of big organic macromolecules present in the wastes. This difficulty is overcome in KR20010091641, but in this case the process is complicated because it must be executed in two phases: a fermentative one and an drying one.

In CN2003-01-08 the wastes are dried after being mixed with lime. Majorly basical fertilizers stabilized by high pH effect which does not permit the bacteria to propagate are obtained. It is necessary to consider that such fertilizers are not adapted for all soils but only for very acid ones and anyway they can meet legal obstacles during their usage. JP5295376 describes a process in which the wastes are mixed with strong oxidants (of peroxyde or perchloride nature) in high percentages. Such oxidants remain in the systems even after drying. The process is more suitable to prepare the organic material as a combustible rather than a fertilizer.

Summary of the invention

The scientific basis of the innovation proposed in the present invention regard a process and the production plant to transform rapidly humid organic wastes in a high-quality fertilizer. Here we mean by humid organic wastes:

1. Organic wastes deriving from the selective collection of urban wastes;

2. Zootechnical wastes deriving from breeding (defecation and skeletons);

3. Wastes deriving from slaughter (skin, bones etc)

4. Rests of raffmation of vegetal and animal fat products including exhausted oil cake;

5. Wastes deriving from industrial transfonnation of agricultural products;

6. Wastes of wood and from wood transformation deriving products (chips, sawdust etc);

7. Vegetal wastes from gardens, parks and greengrocery markets;

8. Muds deriving from the depuration of refluent waters;

The main aspects of the process and the plants which represent the object of the present invention are described below. a) Chemical-physical treatment of the material in a reactor in which the conditions of chemical catalysis linked to the usage of particular catalysts which represent the fundamental element of the proposed innovation are realized. Such catalysts can be constituted by ions of transition metals which can be used both in a free form (anyway hydrated) and in a complexed form preferably with organic polyphenyle and/or polycarboxilic and/or polioxidrilic composts. Here we refer to the numerous existing studies on the interaction between the polyphenolic or organic polycarboxilic materials and transition metals.

It will be necessary to use said ions of the transition metals (preferably complex) when the ions are of cationic nature and when the treated mass of wastes is initially poor of organic substances able to interact efficiently with such cations (or organic substances containing themselves oxidrilic or carbossilic groups). The polyphenolyc or polycarboxilic substances useful for the process of the present invention can derive from industrial processes or from materials deriving from natural composting of organic substances. The important class of humus and fulvic acids belongs to this type of composts. The functional groups located on the surface of such polymers and, hence, exposed on a broad surface are able to complex said ions of the transition metals. The ions in a free or complexed form useful for the aims of the process of the present invention can belong to the following transition metals: iron, copper, magnesium, vanadium, tellurion, palladium, ruthenium, indium, platinum, cobalt,

nickel, chrome, mercury which generate in water environment oxide/reductive pairs which involve ions corresponding to different oxidation states of the same chemical kind and have a standard potential redox comprised between 1.5 and 0 volts. To reduce the costs of process and to avoid the necessity to hold away the metal kinds (which accumulation in the soil is considered hazardous) from the produced fertilizers the catalysts preferably used in the process, object of the present invention are those constituted by ferric or ferrous ions.

The researches of Davies et al. (1997) have demonstrated that when ferric and cupreous ions are added to polyphenolic complexes rich of carboxilic groups these cations are partially reduced to ferrous and cupreous cations. More generally, on the base of conducted experimentation it is possible to assert that in presence of organic masses in which the oxygen circulates they are able to activate the following chains of reaction:

Fe ⁺ + organic biomass + O ₂ *- Fe ^■ + oxidated organic mass (O

Fe ²⁺ + O ₂ Fe ³⁺ +O ₂ - (2)

2 O ₂ ' ^" + 2 H ⁺ O ₂ + H ₂ O ₂ (3)

Fe ²⁺ + H ₂ O ₂ Fe ³⁺ + HO • + H0~ (4)

H0» + organic molecule + O ₂ *~ oxidated organic molecule with a (5)

H0 ^~ + H ^"1" »- H ₂ O lower molecular weight (6)

Scheme 1

As a result of such sequence of reactions the organic mass is smashed (see reaction 5) by action of the HO* radical which is formed in the reaction 4 ( Paciolla et al., 1999). The same is also oxidized as a result of the reaction 1 and of the reaction 5. The ferric cation acts in the complex as a catalyst because it is consumed in the reaction 1 but renewed in the reaction 4. For the functioning of the system the environment initially must be acid because the reactions 3 and 6 request a certain level of acidity. Beginning from less oxidized cations (ferrous or cupreous) the cycle can also start beginning from the reaction 2 which generates the cations in their more oxidized form. The final result of the series of reactions shown on the scheme 1, which are catalyzed by cations of iron independently on the initial oxidation state, consists in the partial oxidation of the organic biomass and in the smashing of a large fraction of the present molecules. The dimension of the process depends obviously on the reaction time, hi the present invention the biomass and the organic molecules inserted in the reactive scheme are majorly constituted by the organic mass of wastes to be treated. The transformation processes of such biomass are optimized as previously said by the presence of polyphenol and/or polycarboxilic substances. A fundamental aspect of this invention is represented by the fact that the catalyst is constituted by the association of the inorganic cations mentioned below and organic substances able to complex them. In case when the mass of the wastes is poor of polyphenol or polycarboxilic substances (the wastes of meal as pasta, bread, meat and fish contain indeed small quantities of such substances) it becomes essential to add polyphenol or polycarboxilic substances to the system in order to induce the reaction 1 which is essential for the catalytic process. In fact, the reactions 1 and 5 guarantee (as the examples shown below demonstrate) the

gradual stabilization of the wastes mass in comparison to bacterial fermentation phenomenon. The experimentations which have led to this patent application have demonstrated that the gradual drying of organic wastes masses at relatively low temperatures and in presence of air and of catalytic quantities of ferric, ferrous, copper or cupreous salts in pH acids conditions (preferably in the interval 3-6 ) and in presence of polyphenol or polycarboxilic substances (naturally present in the biomass or added separately as constituents of the catalyst) conducts both to the oxidation of the hydrocarbon, etheric, thioester and alcohol functions in ketone, aldehyde, carboxylic ones and to the partial smashing of the substances with high molecular weight into substances with lower molecular weight. The cyclic hydrocarbons, butyrs and light thiols responsible for the unpleasant smelt which emits the organic mass simply exsiccated disappear from the mass gradually exsiccated in the presence of the catalyst. The adding of polyphenol substances to the mixes of minced organic wastes and of catalytic quantities of ferrous and/or cupreous salts improbe the state of the final fertilizer with the obtaining of more thin granulations. The polyphenol substances (present in the organic mass or added as constituents of the catalyst) can derive from industrial activity or be natural (for example, they can be added to the mass under form of soil rich of humus containing humic and/or fulvic acids). The optimal quantities of such components will be evaluated by the software of facility management on the base of the composition in fulvic acids of different available matrixes. In any case the quantity of polyphenole substances must be conveniently fixed at least around the order of 1-2% of the treated wastes mass. The quantity of inorganic ions must, on the contrary, be of 1-10 ppm order in comparison to the mass of the wastes. The scheme 1 of reactions demonstrates that it is possible to start from catalysts of iron in their lower oxidation state (in this case the cations in the reduced state are initially formed by effect of the reaction 1) or from a catalyst of iron and copper in their lower oxidation state (in this case the reactions 2 and 4 will generate the correspondent cations in their higher oxidation state).

A further important advantage of the technology related to this invention is mentioned below. The process of smashing and partial oxidation of the organic mass which takes place as a result of a reactive system belonging to the type shown in the scheme 1, generates also a heat development which can sustain (entirely or partially, according to the reactive systems) the energetic contributes requested for the gradual dehydration of the mass. Because of this factor the energetic contributions requested by the process are in fact modest and for such reason the industrial development of the technology has particular relevance from the ecological point of view.

Another important advantage of the proposed process is constituted by the large variety of treatable organic sublayers. Hence, initially it will be possible to use mixes of wastes which have a suitable chemical composition for precious fertilizers production. For this aim it is better to have in the process a phase of automatic mixing of the wastes (as to previous list), in order to obtain balanced charges according to the characteristics we want to assign to the fertilizers. So, they will be able to belong to the category of mixed composted amendements. These fertilizers according to Italian and European laws must have the following technical characteristics: maximum humidity 50%, pH comprised between 6 and 8.5, humic and fulvic carbon in the dry part minimum 7%, organic nitrogen in the dry part at least 80% of total nitrogen, carbon/nitrogen ratio max 25,

total copper in the dry part maximum 150 mg/kg, zinc in the dry part maximum 500 mg/kg. One of the characteristic innovations of this invention regards the methodology, the input charges are chosen with. It will be used an interactive software which using a database of the materials composition and having as input data (entered by the operator) the typologies of available materials, calculates the fractions of the various materials to be treated in order that: i) the chemical-physical parameters of output fertilizers are respected ii) the treatment time and the granulosity of the output material are optimized in the same time. Moreover, on the base of some rheological (viscosity, surface tension of contact water) and chemical-physical (carbon/nitrogen ratio, water content) parameters of the initial materials the junction of fractions of natural amendements having the task to enhance from time to time the volume of the mass and its porosity (diatomaceous soil adding), balance the pH in case it is too acid or basic (addition of ashes of natural wood in case it is necessary to enhance the pH, addition of phosphoric acid in case the is too basic as in case of hen dung treatment), will be calculated. Other phases of the organic masses treatment which are requested for the acting of the proposed technology are:

:) grinding of the materials at an optimal pieces level (particles of some millimeters order); i) the eventual separation of oily components for the production of heat and electric energy to use in the sections of the plant.

The following elements of innovation simultaneously introduced into the process and into the related plants for the rapid transformation of humid organic wastes in fertilizers are underlined and summarized: a) Usage of a catalyst constituted by salts of transition metals and preferably by cations of iron or copper which are able: i) to maintain inside the reaction chamber during the large part of the process a constant concentration of radicals HO* capable to destroy efficiently the proteic substances, the amids, the sugars and the fats under very modest temperature conditions; ii) to oxidate partially the organic mass eliminating all the components with unpleasant smell. These two types of process guarantee the formation, in relatively small time and with very modest heat exchange, of a stable final product with consequent saving of used energy in the process, in comparison to other treatments which use much more high temperatures. The usage of a catalyst in which the salts of iron and copper are associated with natural polyphenols and in particular those of fulvic and humic acids, permits also to obtain fertilizers of high agricultural value. Such components remain in the mature fertilizer in order to develop their transport function of mineral elements useful for the vegetal cultures in the fertilized soils. b) Usage of low pressures inside the reaction chamber which generates the rapid drying of the system with the simultaneous proceeding of the mass stabilization reactions. The preferably used interval of pressure (0.1-1.0 arm.) peπnits to find the condition for which the drying of the material takes place in the same time with the oxidation and efficient smashing of organic material, so that the same is perfectly stabilized in comparison to the subsequent processes of bacteric fermentation. c) Usage of a database and software for the determination of the charges to guarantee the obtaining of optimal formulations of fertilizers. Such database will

contain not only the chemical formulations of different organic wastes but also the information about the viscosity, density and pH of the possible mixtures of different wastes available at the moment. On the base of such parameters it will be possible to calculate the quantity of additional materials of non organic nature to add to formulations in order to enhance the reactive surfaces (porous substances), for the pH optimization (basic ashes or fertilizing acids adding).

Other advantages will be clear from the figures and examples shown below and given in a not limiting way of the invention.

Brief description of the figures

The figure 1 is a non-exhaustive illustration of the principal components of the plant of wastes fertilization.

The figure 2 shows the methodology used in the present invention.

Detailed description of the figures

The main components of the plant as results from the fig. 1 will be:

1) Waste material receiving section with vibrating platform and liquids collector

2) Selector of the humid organic waste

3) Smasher with liquids collector

4) Reaction chambers provided with device for: a) materials loading and catalyst dosing, b) controlled shaking of the organic mass; c) circulation of hot flows and the temperature control; d) pressure regulation

5) Descharge and dryer of the material treated in the reaction chambers;

6) Sieve of the dried material for elimination of plastic or glass wastes

7) Charging device for the reaction chambers

8) Minced material receiver

9) Liquids container

10) Inerts container

11) Oil component separator

12) Container and dosing device for the catalyst

A particularly advantageous version of the production plant of fertilizer using the methodology object of the present invention is described in the following figure 2. The plant presumes that the oil wastes extracted from the RSU or from other matrice of organic wastes (slaughter wastes, exhausted cake etc.) integrated from vegetal oils, are used in a cogeneration plant (a biodiesel engine coupled with AC generator) for the production of electric and heat energy necessary for the energetic alimentation of the reactor for the catalyzed biomass transformation and for all others components of the plant. The separation of fatty or oily substances surpluses in organic masses to fertilize must be avoided for chemical-physical reasons. The first reason consists in the low solubility of the oxygen (a fundamental reagent of organic substances oxidation/smashing process) in the oil substances. Due to this low solubility the oxygen circulation in the wastes mass would be limited what makes the treatment inefficient. For this reason in presence of strongly oil wastes it is better to provide a separator for the large part of the oil substances and use them for the production of the energy to be used in the same plant.

A reduced dimension version of the plant shown below can be able to treat the humid organic wastes produced inside the condominiums. In such case it will be possible to adapt the plant dimensions to the condominium ones, but an almost universal system

could be calibrated to treat up to 100 kg of humid organic wastes a day. A kind of discharge could be provided inside the kitchens of every apartment in order to conduct the wastes introduced into the treating plant for fertilizers production to be collected periodically in a special final container. Also in this case the facility must provide the following components: 1) wastes conveyer 2) biomasses smasher 3) liquids separator (to be conducted to urban waste dump), 4) chamber for accumulating of the smashed and partially dried biomass, 5) reaction chamber of the organic mass stabilization by means of reaction scheme 1, 6) accumulating chamber for the final product. The plant is provided with all controls and automatic procedures necessary to guarantee its automatic functioning.

Examples

All the examples described below have been realized in a prototype of facility capable to treat up to 20 Kg of organic material.

EXAMPLE l

10 Kg of restaurant wastes containing pasta, fish, meat, bread, pizza, fruits (pineapple, melon, apples), potatoes, eggs, grocery; industrial wastes (peaches, tomatoes, grape, wine treating waste or vinace) have been treated.

The material has been preliminarily minced by means of a blade mill with a 10 mm sieve and it has been introduced into the reaction chamber under form of humid and pasty homogeneous material. 200 ml of a 15% of ferrous sulfate and 0.01% of sulfuric acid solution have been added to the material as a catalyzing system.

The material has been inserted into the reaction chamber which internal environment has been heated at 55°C and put under 0.8 atmosphere pressure. The treatment has been conducted for 6 hours. During this period of time the temperature was subject to an excursus up to almost 110°C, being subsequently reduced to 60° C. In the discharge from the reaction chamber the organic mass had the aspect of a material of brown colour, dry, granulous (almost 1 millimeter grains), without smells. The entire treatment took 6 hours.

The maintained material exposed to the air has not developed mould or smells related to the beginning of the bacteric degradation processes.

EXAMPLE 2

This example is analogous to the example 1, but with the adding of 500 gr. of compost containing humic and fulvic acids, hi this case a more thin granulation of final product has been obtained in less time (5 hours).

EXAMPLE 3

10 kg of peaches wastes have been treated. The material has been preliminarily minced by means of a blade mill with a 10 mm sieve and it has been introduced into the reaction chamber under form of humid and pasty homogeneous material. 200 ml of a

15% of ferrous sulfate and 0.01% of sulfuric acid solution as well as 500 grams of soil rich of humus have been added to the material as a catalyzing system.

The material has been inserted into the reaction chamber which internal environment has been heated at 55 ⁰ C and put under 0.8 atmosphere pressure. The treatment has been conducted for 18 hours. During this period of time the temperature was subject to an excursus up to almost 100 ⁰ C, being subsequently reduced to 60° C. In the discharge from the reaction chamber the organic mass had the aspect of a material of brown colour, dry, granulous (almost 1 millimeter grains), without smells.

EXAMPLE 4

This example is analogous to the example 3, but with the adding to the catalyst of 500 gr. of compost containing humus and fulvic acids. In this case a more thin granulation of final product has been obtained in less time (10 hours)

EXAMPLE 5

10 kg of pizza wastes have been treated. The material has been preliminarily minced by means of a blade mill with a 10 mm sieve and it has been introduced into the reaction chamber under form of humid and pasty homogeneous material. 200 ml of a 15% of ferrous sulfate and 0.01% of sulfuric acid solution as well as 500 grams of soil rich of humus have been added to the material as a catalyzing system.

The material has been inserted into the reaction chamber which internal environment has been heated at 55°C and put under 0.8 atmosphere pressure. The treatment has been conducted for 4 hours. During this period of time the temperature was subject to an excursus up to almost 100°C, being subsequently reduced to 60° C. In the discharge from the reaction chamber the organic mass had the aspect of a material of brown colour, dry, granulous (almost 1 millimeter grains), without smells.

EXAMPLE 6

This example is analogous to the example 5, but with the adding to the catalyst of 500 gr. of compost containing humus and fulvic acids. In this case a more thin granulation of final product has been obtained in less time (3 hours)

EXAMPLE 7

10 kg of pizza wastes have been treated. The material has been preliminarily minced by means of a blade mill with a 10 mm sieve and it has been introduced into the reaction chamber under form of humid and pasty homogeneous material. 200 ml of a 15% of ferrous sulfate and 0.01% of sulfuric acid solution have been added to the material as a catalyzing system.

The material has been inserted into the reaction chamber which internal environment has been heated at 55°C and put under 0.8 atmosphere pressure. The treatment has been conducted for 6 hours. During this period of time the temperature was subject to an excursus up to almost 100°C, being subsequently reduced to 50° C. In the discharge from the reaction chamber the organic mass had the aspect of a material of brown colour, dry, granulous (almost 1 millimeter grains), without smells.

EXAMPLE 8

This example is analogous to the example 7, but with the adding to the catalyst of 500 gr. of compost containing humus and fulvic acids. In this case a more thin granulation of final product has been obtained in less time (5 hours)

EXAMPLE 9

10 Kg of restaurant wastes containing bread, pasta, pizza, grapes have been treated. The material has been preliminarily minced by means of a blade mill with a 10 mm sieve and it has been introduced into the reaction chamber under form of humid and pasty homogeneous material.

140 gr. of a water solution containing 7,6 gr. of iron per 100 cc complexed with the organic linking agent of iron with DTPA have been added to the material. Such product is used as fertilizer known as Ferfast. The 5% compost rich of fulvic and humic acids has been added to the mass.

The material has been inserted into the reaction chamber which internal environment has been heated at 55°C and put under 0.8 atmosphere pressure. The treatment has been conducted for 4 hours. During this period of time the temperature was subject to an

excursus up to almost 100 ⁰ C, being subsequently reduced to 60° C. In the discharge from the reaction chamber the organic mass had the aspect of a material of a very dark colour, dry, granulous (almost 1 millimeter grains), almost without smells. The stable material does not demonstrate fermentation processes during the time.

EXAMPLE 10

10 Kg of restaurant wastes containing bread, pasta, pizza, grapes have been treated. The material has been preliminarily minced by means of a blade mill with a 10 mm sieve and it has been introduced into the reaction chamber under form of humid and pastose homogeneous material. 2 kg of compost containing fulvic and humus acids and 200 ml of a 30% of ferrous sulfate and 1% of sulfuric acid water solution have been added to the material.

The material has been inserted into the reaction chamber which internal environment has been heated at 55°C and put under 0.8 atmosphere pressure. The treatment has been conducted for 2 hours. During this period of time the temperature was subject to an excursus up to almost 90 ⁰ C, being subsequently reduced to 55° C. In the discharge from the reaction chamber the organic mass (almost 9 kg) had the aspect of a material of brown colour, dry, granulous (almost 1 millimeter grains), without smells.

EXAMPLE I l

10 Kg of restaurant pasta wastes have been treated. The material has been preliminarily minced by means of a blade mill with a 10 mm sieve and it has been introduced into the reaction chamber under form of humid and pasty homogeneous material. 200 cc of a

20% solution of ferrous sulfate containing 1% of sulfuric acid have been added to the material. In order to activate the catalyst 500 grams of a compost rich of fulvic and humus acids have been added.

The material has been inserted into the reaction chamber which internal environment has been heated at 55°C and put under 0.8 atmosphere pressure. The treatment has been conducted for 6 hours. During this period of time the temperature was subject to an excursus up to almost 95°C, being subsequently reduced to 45° C. In the discharge from the reaction chamber the organic mass had the aspect of a material of brown colour, dry, granulous (almost 1 millimeter grains), without smells.

EXAMPLE 12

The test was executed as in case of the example 7 with the only difference: the green vitriol has been substituted by blue vitriol. In this case the final product was slightly less dark, but it had the same morphology and analogous stability behavior.

EXAMPLE 13

The test was executed as in case of the example 3, with the following difference: the nitrate of ammonium (5% of the wastes mass) have been added in order to obtain a fertilizer with the ratio carbon/nitrogen less than 25, though the initial material had this ratio higher than 80. The obtained material had colour, morphology and stability analogous to those obtained under the conditions of the example 3.

EXAMPLE 14

10 Kg of a wastes mix containing 50% of vegetal wastes deriving from gardens watering and 50% of animals feces (barn) have been treated. The material has been preliminarily minced by means of a blade mill with a 10 mm sieve and it has been introduced into the reaction chamber under form of humid and pasty homogeneous material. 200 ml of a 15% of ferrous sulfate and 0.1% of sulfuric acid solution have been added to the material as a catalyzing system.

The material has been inserted into the reaction chamber which internal environment has been heated at 55°C and put under 0.8 atmosphere pressure. The treatment has been conducted for 6 hours. During this period of time the temperature was subject to an excursus up to almost 100 ⁰ C, being subsequently reduced to 50° C. In the discharge from the reaction chamber the organic mass had the aspect of a material of brown colour, dry, granulous (almost 1 millimeter grains), without unpleasant smells. EXAMPLE 15

This example is analogous to the example 14, but with the adding to the catalyst of 500 gr. of compost containing humus and fulvic acids. In this case a more thin granulation of final product has been obtained in less time (5 hours) ESEMPIO 16

10 Kg of a wastes mix containing 50% of vegetal wastes deriving from gardens watering and 50% of muds deriving from the urban waters sewage have been treated. The material has been preliminarily minced by means of a blade mill with a 10 mm sieve and it has been introduced into the reaction chamber under form of humid and pasty homogeneous material. 200 ml of a 15% of ferrous sulfate and 0.1% of sulfuric acid solution have been added to the material as a catalyzing system. The material has been inserted into the reaction chamber which internal environment has been heated at 55°C and put under 0.8 atmosphere pressure. The treatment has been conducted for 6 hours. During this period of time the temperature was subject to an excursus up to almost 100 ⁰ C, being subsequently reduced to 50° C. In the discharge from the reaction chamber the organic mass had the aspect of a material of brown colour, dry, granulous (almost 1 millimeter grains), without unpleasant smells. EXAMPLE 17

This example is analogous to the example 16, but with the adding to the catalyst of 500 gr. of compost containing humus and fulvic acids. In this case a more thin granulation of final product has been obtained in less time (5 hours) EXAMPLE 18

10 Kg of a wastes mix containing 50% of vegetal wastes deriving from grocery markets and 50% of muds deriving from the urban waters sewage have been treated. The material has been preliminarily minced by means of a blade mill with a 10 mm sieve and it has been introduced into the reaction chamber under form of humid and pasty homogeneous material. 200 ml of a 15% of ferrous sulfate and 0.1% of sulfuric acid solution have been added to the material as a catalyzing system.

The material has been inserted into the reaction chamber which internal environment has been heated at 55°C and put under 0.8 atmosphere pressure. The treatment has been conducted for 6 hours. During this period of time the temperature was subject to an excursus up to almost 100 ⁰ C, being subsequently reduced to 50° C. In the discharge from the reaction chamber the organic mass had the aspect of a material of brown colour, dry, granulous (almost 1 millimeter grains), without unpleasant smells.