ITTO20110752A1 - PROCEDURE FOR THE PRODUCTION OF BIOLIQUIDS OR BIOFUELS - Google Patents

Description

Description of the industrial invention entitled:

"Process for producing bioliquids or biofuels"

TEXT OF THE DESCRIPTION

FIELD OF THE INVENTION

The present description relates to a process for the production of bioliquids or biofuels.

TECHNOLOGICAL BACKGROUND

Bioliquids are liquid fuels that are used in the production of, for example, electricity and heat, while biofuels are used in the transport sector.

These biofuels are produced starting from a biomass or from the biodegradable fraction of products, waste and residues of biological origin (plants and animals) coming mainly from agriculture, forestry and industrial activities. The term biomass also refers to the biodegradable portion of urban waste.

Vegetable oil, for example, is a liquid fuel obtained by squeezing and / or chemical extraction of seeds of oleaginous plants (for example soy, palm, sunflower). In addition to human nutrition, vegetable oil is used as a bioliquid in static engines for energy production.

By subjecting the vegetable oil to a transesterification process, a product is obtained, defined as biodiesel, which can be used, for example, to power engines in the transport sector. Transesterification is a chemical reaction whose main result is the modification of triglyceride molecules by alcohol in the presence of a catalyst, with the formation of a mono-alkyl ester (biodiesel) and crude glycerol.

The biodiesel produced in this way is mainly used as a fuel in transport and as a fuel in the production of electricity and heat.

Bioethanol is a liquid biofuel derived from the fermentation of vegetable biomass with a high sugar content (for example cane, beet, sweet sorghum) and starch (for example maize, wheat, barley, rice). Bioethanol can be used for the production of electricity and heat and as a component of gasoline (in this case it finds application in the transport sector).

The increase in agricultural areas destined for plant cultivation for the production of bioliquids / biofuels and therefore not for food purposes inevitably gives rise to controversies.

The solution often adopted is to import oil, with very high procurement costs, from countries such as South America, India, Southeast Asia and Africa or countries that base their economy on the primary sector. .

However, this solution is also very questionable as it has the disadvantage of subtracting - for the production of bioliquid or biofuel - considerable plant resources that could be used for the nutrition and survival of the poorer social classes of local populations.

The identification of biomasses not coming from dedicated and non-food crops is therefore of fundamental importance.

For example, to obviate the aforementioned disadvantages, non-food materials such as lignocellulosic biomass are used, also resulting from agro-industrial and forestry activities, for the production of bioliquids / biofuels (as described for example in the patent documents WO-A-2011/073781, WO-A-2010/069516 and WO-A-201 0/053681).

However, the production of bioliquids / biofuels starting from lignocellulosic biomass has obvious disadvantages such as the need to use complex and expensive production processes and the production of products with characteristics that make them difficult to use.

For example, oil obtained from lignocellulosic material subjected to pyrolysis (a thermochemical decomposition process of organic materials) has the disadvantage of having high acidity and viscosity, solid waste and high water content and of being endowed with a limited calorific value.

Industrial research and experimental development in this field have made it possible to identify microbial biomass as a valid alternative to biomass of plant origin for the production of bioliquids or biofuels.

Yeasts, and more generally fungi, represent a group of microorganisms used for the production of bioliquids or biofuels.

The patent document WO-A-2011/051977 describes a process for the production of biodiesel starting from a yeast of the genus Pichia. Specifically, the document describes an oil extraction process starting from a biomass consisting of this yeast by centrifugation, homogenization and extraction with solvents. The oil thus obtained is subsequently subjected to a transesterification process to obtain biodiesel.

This process is complex and disadvantageous in economic terms as it requires a plurality of systems - very expensive - necessary to carry out the various phases of the process itself.

WO-A-2008/134836 concerns the production of biofuels from microbial biomasses of yeasts and fungi by extracting the oils contained in these microorganisms. The production of the oily phase takes place by implementing the process called "direct thermopressurized liquefaction" (ELDT). This extraction process involves the use of solvents and catalysts and is carried out at a temperature between 120 and 400 ° C and at a pressure between 1 MPa and 5 MPa.

The process described therein also has operating conditions which require complex and expensive systems. Furthermore, the use of solvents and catalysts contributes to increasing the cost of biofuel production.

SUMMARY OF THE INVENTION

Taking these premises into consideration, the need is therefore felt for improvement solutions, more effective that allow the production of bioliquids or biofuels in process and economic conditions that are more advantageous than what has been done so far.

In accordance with the invention, the aforesaid object is achieved thanks to the solution specifically referred to in the attached claims, which form an integral part of the present description.

The present description concerns a process for the production of a bioliquid or biofuel which includes the following operations:

i) provide a biomass of fungi, preferably yeasts;

ii) subjecting this biomass to pyrolysis obtaining an oily liquid phase and a solid phase; iii) subjecting the oily liquid phase to at least one "upgrade" process, obtaining the bioliquid or biofuel.

The results reported below show that the process described here allows the production of a bioliquid or biofuel with lower acidity and viscosity characteristics and with a significantly higher calorific value than the bioliquids or biofuels obtained from lignocellulosic biomass and from microbial biomass subjected to known processing processes. in art.

Furthermore, the described process allows to obtain bioliquids or biofuels at considerably reduced costs compared to those required for the production of bioliquids or biofuels obtained with the processes known in the art.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be described in detail, by way of non-limiting example, with reference to the attached figure, in which:

- Figure 1: Schematic representation of an embodiment of the process for the production of bioliquids or biofuels object of the present description.

DETAILED DESCRIPTION OF SOME FORMS OF REALIZATION

The invention will now be described in detail, by way of non-limiting example, with reference to a process for the production of bioliquids / biofuels.

In the following description, numerous specific details are presented to provide a complete understanding of the embodiments. The embodiments can be practiced without one or more of the specific details, or with other processes, components, materials, etc. In other cases, well-known structures, materials or operations are not shown or described in detail to avoid obscuring certain aspects of the embodiments.

Throughout this specification, reference to "an embodiment" or "embodiment" means that a particular configuration, structure, or feature described in connection with the embodiment is included in at least one embodiment. Thus, the appearance of the phrases "in one embodiment" or "in a certain embodiment" at various sites throughout this specification does not necessarily refer to the same embodiment. Furthermore, the particular configurations, structures, or features can be combined in any suitable way in one or more embodiments.

injection and encrustations on internal parts of the engine.

The processes used for the growth of yeasts, and more generally of fungi, are commonly known and similar for different species.

The yeasts / fungi that can be used for the production of a biomass to be subjected to pyrolysis according to the present description are yeasts used for example for the production of beer, ethanol, food supplements for animals, for bread making, for water purification. and sewage, for the production of products that are used in the pharmaceutical and nutraceutical sector.

The process described here provides for pyrolysis of both biomass of yeast / fungi specifically produced (primary biomass) and residues and / or waste of biomass production of yeast / fungi for the applications indicated above. The biomass to be subjected to pyrolysis must in any case have a degree of humidity lower than 15-20% by weight, preferably between 5 and 10% by weight.

Yeasts / fungi commonly used for the above purposes and for the production of bioliquid or biofuel according to the present description are, for example, selected from Aspergillus (fisheri, fumigatus, nidulas), Candida (utilis, guilhermondi, oleophila, lopotica), Criptococcus terricolus , Cladosporium (fulvum, herbarum), Eremothecium ashovi, Hansenula (saturnus, ciferrii), Kluyve romyce s fragilis, Lipomyces starkeyi, Phaffia rhodozyma, Rhodutorala (glutinis, gracilis), Rhodosporidium toruxharuxes, Saccisharomycesharvisharuxes, Saccisharomyceshar is lipolytica, Sporidiobolus microsporus, Sporobolymices ruberrimus, Sporidiobolus microspores, Yarrowia lipolytica.

The headings presented here are for convenience only and do not interpret the purpose or meaning of the embodiments.

This description relates to a process for the production of a bioliquid or biofuel which includes the following operations:

i) provide a biomass of fungi, preferably yeasts;

ii) subjecting this biomass to pyrolysis obtaining an oily liquid phase and a solid phase; iii) subjecting the oily liquid phase to at least one "upgrade" process, obtaining the bioliquid or biofuel.

For the purposes of this description, the terms "bioliquid" and "biofuel" are considered synonyms, regardless of the meanings attributed to these terms by current national and foreign regulations concerning bioliquids and biofuels.

The biomass of yeasts / fungi is characterized by a high percentage of carbon (greater than 50% by weight of the same) and does not contain lignocellulosic substances.

The present description demonstrates that, thanks to these characteristics, the biomass of yeast / fungi is an optimal material to be subjected to a pyrolysis process for the production of bioliquids / biofuels.

On the contrary, lignocellulosic materials subjected to pyrolysis determine the synthesis of an oil characterized by high viscosity and corrosivity. Furthermore, when used in static engines or for means of transport such as fuel, the high viscosity and acidity of the oil obtained can cause both damage to the system. bioliquids or biofuels according to this description.

In a first embodiment, a primary microbial biomass 3a, ie specifically produced, is used; the production phase of yeast and / or fungi biomass takes place inside tanks used for the growth of microorganisms, such as fermenters. The yeasts / mushrooms inside the fermenter are fed with nutrients that are prepared and stored in closed steel tanks, equipped with controlled openings, normally subjected to a sterilization phase with a current of steam. The fermenters are equipped with an aeration system to guarantee the microorganisms, grown with the appropriate nutrients, the oxygenation necessary for their growth and proliferation. The fermenters are equipped with probes necessary for measuring the parameters necessary for the growth of microorganisms, i.e. probes for detecting temperature, pH and dissolved oxygen. There is also a system for monitoring the quantity of yeast present in the tank.

In a different embodiment, the microbial biomass 3b derives from residues and / or waste of yeast / fungal biomass production deriving from water and / or sewage purification processes.

The use of a humid microbial biomass (such as that coming from a fermenter 3a or that deriving from water and / or sewage purification processes 3b) involves a drying phase 5 of the wet biomass, i.e. the passage of the same in an operating dryer , for example, thanks to the use of the heat produced by the pyrolysis system.

In the case of a 3c microbial biomass that has already been dried and / or contains a percentage of humidity not exceeding 15-20% by weight, preferably between 5-10%, such as for example a microbial biomass deriving from the production of bread or beer, this can be fed directly to the pyrolysis phase 6.

The biomass of yeasts / fungi to be subjected to the pyrolysis process described here also has the advantage, compared to the lignocellulosic biomass, of not requiring further preparation steps, such as shredding.

Regardless of its origin, the biomass of yeasts / fungi is subjected to the pyrolysis process 6 inside a metal reactor equipped with walls made of materials (for example ceramic and / or refractory) which allow the process to be carried out at high temperatures and in acidic environment.

The biomass of yeast / fungi is introduced into the pyrolysis reactor by means of a screw, preferably in order to avoid the introduction of air.

The pyrolysis phase 6 is carried out in the complete absence of oxygen or in the presence of a reduced quantity of oxygen, sufficiently limited, not to allow combustion phenomena.

The temperature at which the pyrolysis process is carried out is between 500 ° C and 1200 ° C, preferably about 600 ° C.

The pyrolysis process is triggered by methane gas or in any case with an external energy source. Subsequently, the process feeds itself by exploiting the gas produced by the pyrolysis process itself; the gas produced by the pyrolysis process and used to maintain the reactor temperature at the desired level is normally composed of CO: 33-37%, H2: 33-37%, CH4: 28-32%, CO2: 0.5- 1%, N2: 5-7%.

The pyrolysis process determines almost instantaneously (in less than one second from the start of the process) the degradation of the yeast / fungal biomass with obtaining a solid phase (char), a gas phase and an oily liquid phase by condensation.

The oily liquid phase obtained at the end of the pyrolysis is also preferably subjected to a separation step 8 of the residual process water.

The oily liquid phase eventually freed from the excess water is subjected to one or more upgrade procedures 9 for the elimination of any solid residues, improvement of the pH (if acid), increase in calorific value and decrease in viscosity, obtaining at the end of this (i) process (i) of physical upgrade the bioliquid or biofuel.

These upgrade procedures 9 can be selected from: treatment with natural mineral products such as zeolites in order to modify the pH, nanofiltration, passage in a cavitation reactor to obtain a molecular simplification (also called cold cracking), oxidation of the material, stable mixing with water by cavitation.

The solid residue, called char, can be used as an agricultural soil improver or can be further treated, for example with steam, in a reactor 7 to obtain activated carbon with known technology.

Table 1 shows the content, expressed as a percentage by weight, of final products obtained at the end of the pyrolysis process described above and carried out at temperature values equal to 600 ° C and 850 ° C.

Table 1

T =

Products T = 600 ° C 850 ° C

gas 10-20% 63-70%

liquid 65-75% * 15-20%

char 15% 15-17%

activated carbon from

char 12% 12%

Table 1 shows that the products obtained from pyrolysis are both gaseous, both solid (char and activated carbon), and liquid (oily liquid phase) in different proportions depending on the temperature used.

The pyrolysis process carried out at about 600 ° C is more effective as it allows to obtain a greater quantity of oily liquid phase, ie bioliquid / biofuel.

The process described here allows the production of a bioliquid or biofuel with pH which, in relation to the source material and the pyrolytic process, can vary between 5.8 and 7.2.

The pH of the bioliquid or biofuel obtained can be varied by using products such as zeolites.

The calorific value of the bioliquid or biofuel obtained is equal to 20-25 MJ / Kg and this value can be increased up to 30-38 MJ / Kg, depending on the material used and the upgrade technique used.

The bioliquid or biofuel obtained is characterized by a viscosity value at 25 ° C between 20 and 200 cSt, preferably equal to about 20 cSt (variable data depending on the material used and the upgrade system used), a value that is It is significantly lower than that of bioliquids / biofuels obtained from lignocellulosic biomass.

The reduced viscosity of the bioliquid or biofuel obtained by the procedure described is determined both by the lack of lignocellulosic substances in the starting biomass, and by the composition of the starting biomass particularly suitable for pyrolysis (i.e. yeasts), and by the use of aforementioned upgrade upgrades.

The described process allows to obtain a bioliquid or biofuel with characteristics that allow a particularly effective use of it for the feeding of diesel engines, in particular for the production of electric energy and (cogeneration).

The process for producing bioliquids or biofuels object of the present description has numerous advantages over the processes for producing bioliquids or biofuels described in the known art.

The process involves the use of non - food biomasses whose production costs are mainly represented by the costs of the nutrients used for the proliferation of microorganisms and the share of transformation into bioliquid / biofuel. The other cost addenda (for example depreciation, management and personnel costs) affect on average in the order of 22-28% of the total cost of production.

The most economically viable alternative for the production of bioliquids / biofuels is the use of residual yeast / fungi or those coming from remediation / purification activities.

An example, purely by way of non-limiting example, of an embodiment of the process object of the present description will be provided below.

A 3a microbial biomass of an oleic yeast, Rhodotorula Glutinis, is grown with the following nutrients:

- Molasses (previously steamed at 121 ° C for 20 minutes and filtered with activated carbon);

- Technical grade sodium nitrate;

- Technical grade magnesium sulphate.

The daily amount of nutrient is 2.5 g / l of molasses, 0.1 g / l of sodium nitrate and 0.1 g / l of magnesium sulphate. The yeast fed in this way produced lipids in the order of 30% by weight.

To verify the conditions of economic growth, a parameter has been defined, called "Conversion Factor - FDC", which links nutrients to biomass production; this value is linked with a simple mathematical algorithm to the cost of nutrients, for each type of substrate. The FDC is an experimental datum that also depends on the physical-environmental and structural conditions of the crop.

Considering, then, an average generation found in the pyrolysis in bioliquid or biofuel of 50% by weight of the biomass, the cost for the production of biomass is given by the following formula:

n

Ct = ((1000 / (FDC x Qt)) ∠'QiCi) (1 / X)

i = l

where is it :

- Ci = cost in the i-th nutrient (from 1 to n) (euro / kg) Qi = i-th nutrient quantity (gr / lt)

Qt <=> total amount of nutrients (gr / lt)

P = production of microorganism / s (gr / lt of dry material)

- Ct = Nutrient cost under certain growth conditions to produce a ton of oil (euro / ton)

X = share of oil production in the pyrolysis plant (0.5 corresponds to 50%)

- FDC = P / Qt.

The production cost of microbial biomass is inversely proportional to the FDC and directly proportional to the cost of the individual nutrients, in relation to the share of each in the substrate.

With the FDC you have an immediate indication of the economy of the crop in question.

For example, a FDC equal to 2 represents a conversion of a "quantity of nutrients" (for example 2.7 gr / lt day) to obtain "two quantities" (about 5.4 gr / lt day) of dry biomass.

Continuing the example, for a strain of Rhodotorula Glutinis fed with suitably purified molasses (150 euro / ton - 2.5 gr / l) and technical salts (0.8 euro / kg -0.2 gr / l) we have a Ctdi 198 euros, but with a FDC of 0.5 the Ctd becomes 729 euros, which represents a value that is not economically acceptable. Under these conditions, the process is economically advantageous again in the case of molasses at 60 euros / ton and Sali at 0.5 euros / kg with a Ct of 370 euros / ton.

The FDC data found in the growth of Rhodotorula Glutinis are higher than 2 (from 2 to 5.9), considering the other addends to the maximum (28%), and the FDC at 2 with the maximum nutrient costs, we have a cost of bioliquid or biofuel of 275 euros / ton, which is lower than the purchase costs of raw vegetable oil (500-800 euros / ton to which processing costs must be added) and the cost of producing bioethanol (500- 500 euro / ton), demonstrating the economic validity of the process object of this description.

Claims (10)

CLAIMS 1. Process for the production of a bioliquid or biofuel, said process comprising the following operations: i) providing a biomass of fungi, preferably yeasts (3a; 3b; 3c); ii) subjecting said biomass (3a; 3b; 3c) to pyrolysis (6) obtaining an oily liquid phase, a solid phase and a gaseous phase; iii) subjecting said oily liquid phase to at least one upgrade process (9) obtaining said bioliquid or biofuel. 2. Process according to claim 1, wherein said biomass (3a; 3b) is subjected to a drying operation (5) before being subjected to pyrolysis. 3. Process according to claim 1 or claim 2, wherein said biomass (3a; 3b; 3c) has a water content lower than 15-20% by weight, preferably between 5 and 10% by weight. 4. Process according to any one of the preceding claims, wherein said pyrolysis (6) is carried out at a temperature ranging from 500 to 1200 ° C, preferably about 600 ° C. 5. Process according to any one of the preceding claims, in which said pyrolysis (6) is carried out in the absence of oxygen, or in the presence of a reduced quantity of oxygen such as to avoid a combustion of said biomass. 6. Process according to any one of the preceding claims, in which said oily liquid phase is subjected to an extraction phase (8) of the residual water before being subjected to said at least one upgrade process (9). 7. Process according to any one of the preceding claims, in which said at least one upgrade process (9) is selected from: treatment with zeolites, nanofiltration, cavitation, oxidation, stable mixing with water. 8. Process according to any one of the preceding claims, wherein said bioliquid or biofuel has a pH of between 4.5-8, preferably about 7.2. 9. Process according to any one of the preceding claims, wherein said bioliquid or biofuel has a calorific value comprised between 20â € “38 MJ / Kg. 10. Process according to any one of the preceding claims, wherein said bioliquid or biofuel has a viscosity ranging from 20 to 200 cSt at 25 ° C, preferably about 20 cSt at 25 ° C.