WO2014125133A1

WO2014125133A1 - Unit and method for improving the biodegradability of sources of organic material

Info

Publication number: WO2014125133A1
Application number: PCT/ES2013/070082
Authority: WO
Inventors: Pablo DE ANDRÉS GARCÍA
Original assignee: De Andrés García Pablo
Priority date: 2013-02-12
Filing date: 2013-02-12
Publication date: 2014-08-21
Also published as: ES2550247A2; ES2550247B1; ES2550247R1

Abstract

The invention relates to a unit comprising multiple elements, essentially characterised by the use of high-power cavitation/friction mixers which are used together with dispersants and oxidants in multiple steps in series, as well as including an increase in the prior temperature in a continuous process. The device is based on the heating of organic material and dividing same into fine particles by means of cavitation-dispersion and on the chemical oxidation of the cell membranes and walls, all in order to promote conditions for biodegradability. The final operation is the result of the joint action of multiple systems that combine physicochemical dispersion forces, chemical oxidants and temperature. This combination multiplies the effect and minimises reagent and power costs. The unit comprises two heating modules, measurement and control means, a cavitation-dispersion reactor (7), a membrane-rupture cavitation reactor (8), and a sterilisation reactor (9), as well as a controlled acidification reactor. The invention can be used to improve the biodegradability of material and, consequently, the final energy yield.

Description

INSTALLATION AND PROCEDURE FOR IMPROVING THE

BIODEGRADABILITY OF SOURCES OF ORGANIC MATTER

DESCRIPTION

OBJECT OF THE INVENTION

The object of the present invention, as the title of the invention establishes, both an installation and the procedure carried out in said facility that allows the improvement of the biodegradability of organic matter, in order to subsequently produce biogas that by its high Methane content is a source of usable energy.

The origin of the organic material used can have a very diverse origin from petroleum by-products, algae cultures, industrial waste, urban garbage, leachate, oils, livestock, agricultural, forestry residues, sewage sludge waste called sludge, sludge and similar etc.

It characterizes to the present invention the special characteristics of each one of the elements that form part of the installation as well as the stages to which the organic matter particles are subjected in order to increase the biodegradation, favoring the environmental physical-chemical conditions. biological so that it is carried out at a higher speed. Therefore, the present invention is circumscribed within the scope of the means and facilities designed for the treatment of sludge and the like in order to improve their subsequent treatment.

BACKGROUND OF THE INVENTION

Numerous attempts have been made in the state of the art to facilitate the biodegradability of organic matter (OM) sources. The origin of these sources can be of very different origin, petroleum by-products, algae crops, industrial waste, urban garbage, livestock, agrarian, forestry residues, sewage sludge waste called sludge, etc.

i It has proceeded with various technologies, such as microwaves, thermal methods, ultrasounds, however obtaining few results in terms of economic viability, electrical or energy consumption. These systems therefore have not had an effective introduction in the market due to their low utility, complexity, high operating costs and maintenance.

Non-toxic sources of organic matter, under suitable conditions, are potentially susceptible to fermentation and bidegrading, it is intended to increase biodegradation, favoring the physical-chemical-biological environmental conditions so that it is carried out at a higher speed. Under aerobic conditions organic matter is biodegraded by partially or completely oxidizing. Under anaerobic conditions it biodegrades producing biogas and residue. This gas, due to its richness in methane, is a usable source of energy, easy to use, distribute and transform, being much in demand today.

Many of these sources of organic matter are by-products or waste from which their energy potential is used, volume is reduced, dehydration and subsequent use are facilitated, their valorization is increased. The energetic use of these sources of organic matter is a fundamental object of this industrial development and has its main interest in economic, environmental and health benefits.

Therefore, it is the object of the present invention to develop an installation and a procedure associated with said installation that allows the use of organic matter as a source of biogas and consequently as a source of usable energy, by improving the biodegradability of the organic matter, developing an installation such as the one described below and is included in its essence in the first claim.

DESCRIPTION OF THE INVENTION

The invention of installation for the improvement of biodegradability is characterized in that it comprises several elements, the fundamental part being the application of high-energy friction-cavitation blenders and their joint application with dispersants and oxidants in several steps in series, completed with the increase of the previous temperature in a continuous process. The equipment is based on heating of organic matter, its division into fine particles with cavitation-dispersion, in the chemical oxidation of walls and cell membranes, all this to favor the biodegradability conditions in concrete to the limiting phase (hydrolysis)

The final action is the result of the combined action of several systems in which chemical physical dispersion forces, chemical oxidants and temperature are combined. When combined, the effect multiplies and minimizes reagent and energy costs. The installation and the procedure are looked for:

Improve the production and use of energy in the form of biogas generated.

Improve the reuse of by-products generated in different processes.

Increase in dry matter concentration in anaerobic reactors. - Decrease in the viscosity of the medium.

A saving of costs of treatments, transport, volumes of mud, equipment and civil works.

Easy implementation in existing facilities.

Continuous process

- Increase in the capacity of existing digesters.

Energy recovery by the double exchanger.

A sanitary improvement, since the sludge reduces or eliminates pathogens.

Permit a direct application of waste complying with European regulations.

- A decrease in dry matter due to transformation in biogas and reduction of salt precipitations due to the action of dispersants.

A reduction of volumes in materials destined to landfill.

An environmental improvement, less impact of waste and better waste management.

- A valorization of waste and greater humic richness.

To achieve these purposes, the installation includes:

Means for measurement and control

- Heating means

A series of reactors arranged in series

A means for heat recovery. An acidification control reactor The means for measurement and control in turn comprise:

a) a flowmeter with which the volumes of treated material and the dosages of reagents are controlled.

b) sensors that give us information about conductivity, pH, temperature, redox, that help us to control the system and its operation.

c) A Sonometer-vibrometer to measure the cavitation in the reactors and their control.

The means for heating comprise two material heat exchangers, which will favor the following processes in the treatment, dispersion, cavitation, oxidation and acidification.

The temperature provides the following effects:

It contributes to the dispersants and reduces the viscosity of the medium.

Temperature also favors cavitation because the vaporization pressure is lower.

Increases the effectiveness of chemical oxidation reactions.

The temperature accelerates the processes of natural acidification.

Increases the dissolution of salts, avoiding "fouling" in the reactors. "Fouling" is a term that refers to saline incrustations, fouling on walls and agitators of reactors, pipes, etc.

Increases the sterilization effect.

The most efficient temperature to achieve will be the pasteurization, depending on the sterilization needs of the material to be biodegraded may be higher, it will also depend on the use of excess thermal energy in cogeneration engines and the management of anaerobic reactors (mesophiles or thermophiles) or aerobic in the following treatments.

The heating means comprises:

to. A primary heating unit based on a main exchanger in which the temperature of the output material of the process will be used to preheat the new material in countercurrent. b. A secondary heating unit based on a secondary exchanger in which an extra contribution is made to raise the temperature to levels higher than those of pasteurization and favoring the dispersion and grinding of the material by the blenders.

The reactors arranged in series include: a) Cavitation reactor - dispersion: This reactor has a high energy agitator that produces mechanical cavitation in the medium. In addition there are pressure variations, micro implosions that crush the material to be treated, providing high friction to the material.

It is dosed soda tenactivated and additivated with antiscalants (sequestrants and coadyugantes) biodispersantes that increase the mechanical effect of shearing of the propeller, avoiding the inorganic precipitation of salts phosphates, carbonates, struvita.

Biodispersants produce the chemical dispersion of fatty substances linked to exopolymers, hydrocarbon residues, oils and hydrophobic substances.

The cavitation produces implosions of microorganisms when there is a vaporization of water inside the cell and there is cytoplasmic material release.

The cavitation control is carried out with sound level sensors, vibrometers.

In this deposit or reactor an effective disintegration of the Matter takes place.

Organic in small particles more easily biodegradable. On the other hand, the increase in surface area leads to an increase in the efficiency and speed of biodegradability.

In this reactor a physical-chemical combination is produced that multiplies the effects of dispersion. The propeller has a double mechanical effect, one of friction agitation cutting structures and polymeric molecules and another of cavitation. These effects are increased by the action of increased temperature at the start, increased capacity of vaporization, which decreases the viscosity of the medium and increases the reactions and on the other hand the multiplying effect of the reagents used biodispersants such as the soda tensoactivated and additivated. The soda increases the alkalinity and raises the pH to the medium and favors the lower inhibition by pH in the subsequent acidification stage. b) Cavitation reactor rupture of membranes. In the next tank, a chemical oxidant (Chlorine dioxide) is dosed on the agitation cavitation zone with a high-speed equipment similar to that of the first reactor. This oxidant has a great tendency to oxidize cell membranes and leave the cytoplasm free in the most accessible medium for its degradation. Additionally, it has the advantage that it is very fast acting and does not incorporate byproducts or toxic residues such as enduring chloramines that complicate subsequent biological processes.

The oxidizing capacity of chlorine dioxide is increased by the OH- radicals of cavitation.

In this reactor, it is possible to damage the permea bers and to reduce the cytoplasmic membrane, producing a greater amount of easily biodegradable and accessible material that is no longer protected by the barrier of exopolymer material and the cellular membrane. The microorganisms that are still dead if they have complete membranes are more difficult to degrade than if their membranes are broken.

With this system, the thermal and physical factor of the cavitation agitator is multiplied with the chemical oxidation effect. c) Cavitation reactor sterilization

In this step, ozone and steam are dosed, which results in a new oxidant shock in the bacteria that are dispersed and damaged, and also an osmotic and thermal shock provided with the steam at 3 bar increasing the sterilization power of the previous reactors. The means for heat recovery comprises a countercurrent exchanger that transfers the heat to the new input material, so that the heat is used again and the next phase is not compromised by a thermal excess. The outlet temperature should not be higher than 40 degrees centigrade, maintaining the mesophilic conditions of the next step. d) The acidification reactor

It is a deposit with several hours of retention, in this phase there are bacterial growths that produce reactions of hydrolysis, fermentation, biological acidifications that cause pH drops close to 4. (Limit of biological acidifications), the pH is controlled around 5 , 5 to favor the continuous acidification, dissolution of precipitated salts. This fact favors, to a greater degree, the environmental changes for possible pathogens, contributing to the sterilization and the formation of fatty acids that will be transformed or into methane if there is an anaerobic digestion or oxidized in an aerobic system. An effective dissolution of the precipitated carbonates, phosphates, struvite, an increase of the etching surface of the acids on passivated surfaces of calcite carbonates is produced, the Ca2 + and Mg2 + ions being sequestered by the additive, an increase of the surfaces is produced of biological degradation. The method object of the invention comprises the steps of:

Supply of the material to be treated

Pass through a primary heating unit based on a main exchanger in which the temperature of the process output material will be used to preheat the new material in countercurrent.

- I pass means for measurement and control that include: a flow meter, a n Sonometer-vibrometer, sensors that give information on conductivity, pH, temperature, redox, that help control the system.

I pass through some reactors in series equipped with high cavitation and energy stirrers. The reactors through which the organic matter passes are: ■ Cavitation reactor - dispersion where it is dosed soda-activated and additivated with antifouling agents (sequestrants and coadjutants) ^■ Membrane rupture cavitation reactor where a chemical oxidant is dosed (chlorine dioxide)

^■ Cavitation sterilization reactor, where ozone and steam are dosed, which results in a new oxidant shock in the bacteria that are dispersed and damaged, and also an osmotic and thermal shock with the steam at 3 bar.

Step through the primary heating unit where the calorific contribution to the new input material to be treated occurs

Step towards a reactor of acidification equipment bacterial growths that produce reactions of h i d ról i s i s, fe rm entaci n, biological acidifications that cause falls of pH occur.

Thanks to the characteristics of both the installation and the stages of the procedure, the following is achieved:

- Obtain a very effective dispersion of the input material.

The rupture cytoplasm.

An increase in biodegradability by increasing the rate of hydrolysis.

A very low effective particle size.

A degree of coagulation reunification is very low.

- A reduction of inorganic chemical precipitation.

A variation of the thixotropy of the material with a lowering of the viscosity.

A more fluid sludge, which retains less amount of gas in digestion, less energy of agitation of the digester, dispersion of creams, oils, hydrocarbons, foams with their integration in the medium.

- A displacement emulsion dispersion towards the dispersion of the fatty materials, reduction of foams in digestion due to fats incorporated in exopolysaccharides.

Less effect of creams produced in anaerobic digesters by incorporation of filamentous aerobic sludge.

- physical changes very fast and very extreme with respect to the initial conditions, changes in pH, temperature, conductivity, surface tension, thixotropy, these aspects cause that conditions are created that hinder the activity and survival of pathogens and their forms of resistance .

A very rapid chemical changes by the action of chemical oxidants such as chlorine dioxide and ozone make the forms of resistance have difficulty to reactivate to be their walls and cell membranes damaged or punctured by rusting. An absence of inorganic precipitation of carbonates and struvites.

A smaller amount of waste.

EXPLANATION OF THE FIGURES

To complement the description that is being made and in order to help a better understanding of the characteristics of the invention, according to a preferred example of practical realization thereof, a set of drawings is attached as an integral part of said description. where, with illustrative and non-limiting character, the following has been represented.

In figure 1, we can see a schematic representation of the installation object of the invention. PREFERRED EMBODIMENT OF THE INVENTION.

In view of the figures, a preferred embodiment of the proposed invention is described below. In figure 1 we can see that the installation comprises an entrance (1) of the material to be treated, which is passed through a primary heating unit (2), which is an exchange unit that takes advantage of the heat of the output material for preheating the new material in countercurrent; by means of a conduit (3) it is connected to a means of measurement and control comprising: a) a flow meter (4) with which the volumes of material treated and the dosages of reagents are controlled.

b) U sensors (5) that give us information on conductivity, pH, temperature, redox, that help us to control the system and its operation. c) A Sonometer-vibrometer to measure the cavitation in the reactors and their control.

Then, after passing through the measuring and control means, the material to be treated is passed through a secondary heating unit (6) based on a secondary exchanger in which an extra contribution is made to raise the temperature to levels higher than the of pasteurization and favoring the dispersion and grinding of the material by the blenders. Then the material to be treated is first passed through a cavitation-dispersion reactor (7), then through a membrane rupture cavitation reactor (8), and finally through a sterilization reactor (9).

All the reactors (7), (8) and (9) have a high cavitation and energy agitator (10) have:

An agitator (10.1) of high rpm with frequency inverter

A cavitation zone (10.2) in which the agitator (10.1) is housed and to which an air inlet (10.5) for cavitation and a reagent injection inlet (10.4) are connected.

One inlet (10.3) for air-water coolant injection of the agitator shaft (10). "Striping" of C0 ₂ and increase in pH, that is, control of pH by Striping.

"Stripping" of C0 ₂ is the elimination effect of C0 ₂ in a saturated sample when putting other gases, this C0 ₂ is eliminated to the atmosphere and there is a jump of pH, this rises when the C0 ₂ disappears from the solution that It was in the form of carbonic acid. Depending on the type of reactor, the injection of reagents will be different. Thus, in the dispersion cavitation reactor (7), there will be an input (7.1) of soda and dispersants, in the membrane rupture cavitation reactor (8), there will be an entry (8.1) for injection of chlorine dioxide, and in the sterilization cavitation reactor (9), there will be an inlet (9.1) for ozone and steam injection

All the cavitation reactors (7), (8) and (9) have valves at their entrance and their exit can be bypassed with multiple combinations, so the reactor (7) have the valves (7.2) and (7.3) , the reactor (8) with the valves (8.2) and (8.3) and the reactor (9) with the valves (9.2) and (9.3). All the reactors (7), (8), (9), also have an inspection door (7.4), (8.4), (9.4) respectively.

All the cavitation reactors (7), (8) and (9) besides being connected in series, have a by-pass (7.5), (8.5) and (9.5) that bypass the entrance and exit of each reactor, and present at their entrance a valve of (7.6), (8.6) and (9.6) respectively. The acidification tank (11) comprises an agitator (1.1) arranged at its bottom, a vent (1.1.2) and an overflow (1.1), both arranged at the top, a drain (1.4) and an outlet duct (12)

Having sufficiently described the nature of the present invention, as well as the manner of putting it into practice, it is noted that, within its essentiality, it may be implemented in other embodiments that differ in detail from that indicated by way of example. , and to which it will also reach the protection that is sought, as long as it does not alter, change or modify its fundamental principle.

Claims

1.- Installation for the improvement of the biodegradability of sources of organic matter, characterized because it includes:

- Means for measurement and control

A means of warming

A series of reactors arranged in series that have high-energy friction stirrers - cavitation and their joint application with dispersants and oxidants in several steps in series,

- A means for heat recovery

An acidification reactor

2.- Installation for the improvement of the biodegradability of sources of organic matter, according to claim 1, characterized in that the means for measurement and control in turn comprise:

3. - Installation for improving the biodegradability of sources of organic matter, according to claim 1, characterized in that the means for heating comprise two heating units:

a primary heating unit based on a main exchanger in which the temperature of the process output material will be used to preheat the new material in countercurrent and

a secondary heating unit based on a secondary exchanger in which an extra contribution is made to raise the temperature to levels higher than those of pasteurization and favoring the dispersion and grinding of the material by the blenders.

4. - Installation for improving the biodegradability of sources of organic matter, according to claim 1, characterized in that the reactors arranged in their series are:

a cavitation-dispersion reactor (7), a membrane rupture cavitation reactor (8), and

a sterilization reactor (9).

5.- Installation for the improvement of the biodegradability of sources of organic matter, according to claim 4, characterized in that all the reactors (7), (8) and (9) have a high cavitation and energy stirrer (10) have with:

An agitator (10.1) of high r.p.m with frequency variator with high friction blades and cavitation.

One inlet (10.3) for air-water coolant injection of agitator shaft (10) and pH control by Striping.

6.- Installation for the improvement of the biodegradability of sources of organic matter, according to claim 4 or 5, characterized in that the dispersion cavitation reactor (7) has an input (7.1) of additivated soda and dispersants,

7. - Installation for improving the biodegradability of sources of organic matter, according to claim 4 or 5, characterized in that in the membrane rupture cavitation reactor (8) there is an inlet (8.1) for injection of chlorine dioxide,

8. - Installation for improving the biodegradability of sources of organic matter, according to claim 4 or 5, characterized in that in the sterilization cavitation reactor (9), there is an inlet (9.1) for ozone and steam injection

9. - Installation for the improvement of the biodegradability of sources of organic matter, according to claim 4 or 5, characterized in that all the cavitation reactors (7), (8) and (9) have valves at their entrance and their output, so the reactor (7) have the valves (7.2) and (7.3), the reactor (8) with the valves (8.2) and (8.3) and the reactor (9) with the valves (9.2) and (9.3) ).

10. - Installation for the improvement of the biodegradability of sources of organic matter, according to claim 4 or 5, characterized in that all the reactors (7), (8), (9), also have an inspection door (7.4) , (8.4), (9.4) respectively.

1. Installation for the improvement of the biodegradability of sources of organic matter, according to claim 4 or 5, characterized in that all the cavitation reactors (7), (8) and (9) are connected in series in a continuous process, have a by-pass (7.5), (8.5) and (9.5) that bypasses the entrance and exit of each reactor, and present their entry to a valve entrance (7.6) (8.6) and ( 9.6) respectively.

12.- Installation for the improvement of the biodegradability of sources of organic matter, according to claim 1, characterized the acidification tank (11) comprises an agitator (11.1) arranged in its bottom, a vent (11). 2) and an overflow (1 1.3), both arranged in the upper part, a drain (11.4) and an outlet duct (12).

13. Process for improving the biodegradability of sources of organic matter carried out in the installation previously claimed, characterized in that it comprises the steps of:

Supply of the material to be treated

I pass some means for measurement and control that include: a flow meter, a sonometer-vibrometer, sensors that give information on conductivity, pH, temperature, redox, which help control the system.

I pass through some reactors in series equipped with high cavitation and energy stirrers.

Step towards a reactor of acidification equipment bacteriological growths that produce reactions of h i d ró lis s, ferm entation, biological acidifications that cause falls of pH close to 4 occur.

14. Process for improving the biodegradability of sources of organic matter according to claim 13, characterized in that the reactors through which organic matter passes are:

o Cavitation reactor - dispersion where it is dosed soda-activated and additivated with antifouling agents (sequestrants and coadjutants) o Membrane rupture cavitation reactor where a chemical oxidant is dosed (Chlorine dioxide)

o Cavitation sterilization reactor, where ozone and steam are dosed, which results in a new oxidant shock in the bacteria that are dispersed and damaged, and also an osmotic and thermal shock with the steam at 3 bar.