Model for organizing and grouping several stages of processing and recycling coffee grounds into valuable resources.

Abstract

The invention relates to a model for transforming coffee grounds (A) according to two distinct processes: either by methanation (C) into biogas (D) and digestate-fertilizer (E), or / and, first after drying (K) into coffee grounds residue (L), used for pelletizing-granulation (O) and / or extraction with supercritical CO2 (M) of the bioactive components (N), then by pyrolysis (R) of the pellets (P) into biochar (S) and electrical and thermal energy (T) Figures

Description

Title of the invention: Model for organizing and grouping several stages of processing and recycling coffee grounds into valuable resources. Technical field of the invention

[0001] The said invention presents a model for organizing several stages of processing coffee grounds, providing for both the production and extraction of assets, granules, fertilizer, biochar, biogas, thermal and electrical energy from coffee grounds and allowing at each stage of production, the reuse of the components obtained - including waste - to create valuable materials for new consumables.

[0002] Technological background

[0003] In metropolitan France, the amount of coffee grounds generated is estimated at around 450,000 tonnes each year. These colossal quantities of coffee grounds are rarely recovered and are generally simply thrown away or sometimes incinerated. In reality, this is a potentially toxic waste product that can be dangerous to public health. Until now, the coffee industry has perfectly embodied the linear production model: EXTRACT, PRODUCE, CONSUME, and DISCARD. Coffee grounds from bars, coffee machines, capsules, or the instant coffee industry were generally considered mere waste, without any particular commercial value, destined to be thrown away or composted. They represent a significant source of waste given the current global consumption of coffee, approximately 140 million bags, or 8,400,000 tonnes. One kilogram of ground coffee generates 1.3 kg of coffee grounds.On average, coffee grounds represent a 30% weight increase compared to roasted coffee. In 2022, France imported approximately 7 million 60 kg bags, totaling 420,000 tonnes. These 420,000 tonnes of coffee can be considered to have generated a potential of nearly 546,000 tonnes of coffee grounds in France. These colossal quantities of coffee grounds are primarily disposed of in landfills. Indeed, coffee grounds are an organic material requiring large amounts of oxygen to decompose. If not treated effectively, as a result of anaerobic fermentation, they become a source of greenhouse gas emissions: CO2 and methane. Furthermore, they contain caffeine, tannins, and polyphenols, which make them toxic to the environment if stored in a landfill. The global warming potential of methane is 25 times higher than that of CO2.It is clear that the treatment of coffee grounds represents a significant issue in terms of mitigation. This is due to both climate change and the emissions avoided through recycling and recovery. The efficient processing and recovery of coffee grounds could significantly contribute to a positive increase in emissions avoided in France, Europe, and worldwide, as coffee, a now universal beverage, is the most traded agricultural commodity globally, surpassing wheat, which is second only to oil. However, industrial-scale recycling of coffee grounds, the only effective treatment method for this toxic waste, does not currently exist.Currently, there is no specific industrial model for processing coffee grounds that provides for both the production and extraction of active ingredients, granules, biochar, fertilizer, biogas, thermal and electrical energy from coffee grounds, and that allows, at each stage of production, the reuse of the components obtained - including waste - to create valuable materials for new consumables. Presentation of the invention

[0004] The present invention, in its ultimate purpose, aims in particular to make a significant contribution to the emergence of a circular economy for coffee. This circular approach to the exploitation of coffee resources contrasts with the uncontrolled exploitation that has prevailed until now. The circular model generates a cascading reduction in the consumption of natural resources, energy consumption, and therefore greenhouse gas emissions. To this end, it proposes an innovative model for organizing and grouping several stages of coffee grounds processing, providing for both the production and extraction of active ingredients, granules, biochar, fertilizer, biogas, and thermal and electrical energy, and enabling the reuse of the components obtained at each stage of production to create valuable materials that can be reused. Description of the figures

[0005] The invention will be better understood and other features and advantages will become more apparent upon reading the following description, given by way of purely illustrative and non-limiting examples, with reference to the accompanying drawing in which [Fig. 1] [Fig. 1] presents the model of the coffee grounds processing unit according to the invention, shown overall and schematically. Description of embodiments

[0006] Figure 1 shows the model of the coffee grounds processing organization, which, according to the invention, involves dividing the received coffee grounds into two parts that are processed independently. During processing, the coffee grounds undergo physicochemical transformations and acquire different properties at each stage. In accordance with the invention, the components obtained at each stage They can be reused for the next stage of processing or sold in various markets such as cosmetics, pharmaceuticals, energy, agriculture, construction, or others. Therefore, it is important to distinguish from the outset: 1. Coffee grounds after methanation (C) and coffee grounds after drying (K), extraction (M), pelletizing (O), pyrolysis (R).

[0007] The first treatment solution: methanation of coffee grounds (C) for the production of biogas and digestate

[0008] The production of biomethane from coffee grounds is a solution that allows for the treatment and sustainable valorization of this organic matter by transforming it into renewable energy – biogas (D), soil fertilizer (E), and valuable components – lignin (I). At the methanization site (C), the coffee grounds collected for biogas production are prepared to feed the digester. The inputs are introduced into the digester and then into a post-digester – closed, oxygen-free chambers where they are stirred and heated for several days to enable biogas production (D). The methanization of coffee grounds (C) also generates a natural fertilizer called digestate (E). This is an organic matter recognized for its agronomic properties that can then be used (E1) to be spread on agricultural land as a substitute for synthetic fertilizers.The digestate also contains undegraded organic matter – lignin (I) – which, through extraction processes (G), can be separated from the plant biomass to obtain high-quality chemicals. In the methanation process, bacteria transform the matter into biogas (D), primarily composed of methane and carbon dioxide. The purification phase (F) transforms the biogas (D) into biomethane (H). After several stages, it is desulfurized, dehydrated, and decarbonized to become biomethane. After being checked for safety reasons, the biomethane (H) is injected (J) into gas distribution networks (Jl) for uses such as heating, hot water, and fuel. It can also power the coffee grounds processing facility (Z). It is entirely possible to simultaneously produce heat and electricity through cogeneration using an engine fueled by biomethane (F).

[0009] The second treatment solution: pyrolysis of coffee grounds and the production of granules, biochar, energy and active ingredients

[0010] The transformation comprises 5 successive steps. It should be noted that at each step, a "product" is obtained which is reused in the next step. For example, the coffee grounds residue (L) after extraction (M) and without active ingredients (L) are used to produce granules (P) and the granules (P) to produce biochar (S). 1. First, the coffee grounds require drying (K) to control and lower their moisture content to recommended levels in order to obtain the best yield from the processing. The energy required for this step is supplied among other things (Z) by part of the surplus released (T) during the pyrolysis process (R), which generates biochar (S). 2. Next, the coffee grounds residue (L) after drying (K) is optionally used to extract active components (N) using supercritical CO2 (M). The principle of plant extraction using supercritical carbon dioxide allows for the selective extraction of molecules according to their chemical nature. Being very weakly polar, CO2 proves to be an excellent solvent for nonpolar or slightly polar molecules under supercritical conditions. Based on this principle, once the desired compound is dissolved in the CO2 medium, it is easy to obtain the pure extract by simple depressurization, which then separates the CO2 from the extract. 3. After drying (L) and possible supercritical CO2 extraction (L), the coffee grounds residue is assembled or agglomerated to form pellets (P) – larger particles. This process is called pelletizing or granulation (O). The coffee grounds have a suitable consistency for conversion into pellets, enabling several applications. The pellets (P) can either be used (Pl) as a source of thermal energy or converted into biochar (S) by pyrolysis (R). 4. Biochar production (S) – pyrolysis (R) is based on the principle of "dry carbonization." Heating waste in the absence of oxygen results in simple thermal decomposition without any reaction processes such as oxidation or gasification. This is referred to as pyrolysis (R), the products of which are a mixture of light, non-condensable gases, heavy hydrocarbons, fixed carbon coke, and residual inert matter, the relative proportions of which depend on the treatment conditions. If the waste is heated slowly and / or at a low temperature, coke production will be favored. Conversely, if it is heated rapidly and / or at a high temperature, gas production will be favored. This is because rapid heating at a high temperature reduces the probability of secondary reactions that would recombine light hydrocarbons into heavier hydrocarbons.Thus, in slow pyrolysis at low temperature, the product of the decomposition reaction will be predominantly solid (coke), and the pyrolysis gases (tars and gases) can be reburned to provide the heat energy necessary for the decomposition of the waste. Pyrolysis (R) comprises four main steps: 1. Pellet preparation (P), 2. The pyrolysis phase (R), 3. Treatment of carbonaceous solids – biochar (S), 4. Energy recovery (T). The pyrolysis process (R) thus makes it possible to obtain biochar (S) which can then be used (Sl) as a fuel. fertilizer, soil improver, as an adsorbent of polluting substances in water, air and soil treatment, as an alternative to charcoal and sand in the construction industry in various mixtures such as concrete, asphalt, as an ingredient mixed with fibers, deodorizer in the textile industry or as an ingredient in the cosmetic and food industries. 5. The pyrolysis process (R) also generates electrical and thermal energy (T) which is fed (U) into the electricity grid (Ul). It can also power the coffee grounds processing structure (Z). List of reference signs

[0011] (A) is the industrial model for processing coffee grounds,

[0012] (B) is the storage unit for the received coffee grounds,

[0013] (C) is the site of the methanization of coffee grounds,

[0014] (D) is the biogas captured during the methanation of coffee grounds

[0015] (E) is the digestate-fertilizer storage unit resulting from the methanization of pomace of coffee,

[0016] (El) is the use of digestate from coffee grounds as a soil fertilizer

[0017] (F) is the biogas purification unit captured during the methanation of coffee grounds and its transformation into biomethane and thermal or electrical energy,

[0018] (G) is the unit for extracting undegraded organic matter and / or matter minerals from the digestate produced by the methanization of coffee grounds,

[0019] (H) is biomethane and green energy from biogas captured during the Coffee grounds methanization

[0020] (I) is undegraded organic matter such as lignin or mineral matter derived from extractions from digestate from the methanation of coffee grounds,

[0021] (1.1) is the use of lignite derived from coffee grounds to improve the fluidity of detergents, cosmetics, industrial sludge, paint, adhesives, inks, in the production of bioplastics, to replace glass or carbon fibers, as an emulsifier in the building industry, in various mixtures such as concrete, asphalt, dyes and waxes, as a substitute for carbon black in tires.

[0022] (J) is the unit for injecting biomethane and energy into electrical networks and gas

[0023] (Jl) is the electricity and gas networks

[0024] (K) is the coffee grounds drying unit

[0025] (L) is the residue of the coffee grounds after drying and before the extraction of the principles active ingredients with supercritical CO2

[0026] (E) is the residue of coffee grounds after drying and extraction of the active ingredients with CO2

[0027] (M) is the supercritical CO2 extraction unit for the active ingredients of the pomace of coffee after drying

[0028] (N) is the active ingredients obtained from supercritical CO2 extractions from the coffee grounds

[0029] (Nl) is the use of active ingredients from coffee grounds by CO2 extractions supercritical fluid in cosmetic and pharmaceutical compositions

[0030] (O) is the pelletizing unit, also called granulation of the pomace residue of coffee after drying and / or extraction of active ingredients with supercritical CO2,

[0031] (P) is the granules of coffee grounds,

[0032] (P. 1) is the use of coffee grounds granules as a more calorific value of firewood and source of thermal energy

[0033] (R) is the unit for the pyrolysis of coffee grounds granules,

[0034] (S) is the unit for the recovery and storage of solid waste - biochar,

[0035] (S. 1) is the use of biochar derived from coffee grounds, as a fertilizer, as a soil amendment, as an adsorbent for pollutants in water, air, and soil treatment, as an alternative to charcoal and sand in the construction industry in various mixtures such as concrete and asphalt, as an ingredient blended with fibers in the textile industry, as a deodorizer, or as an ingredient in the cosmetics and food industries

[0036] (T) is the energy recovery unit

[0037] (U) is the unit of energy injection resulting from the transformation of coffee grounds by pyrolysis in electrical networks

[0038] (Ul) is the electricity and gas networks

[0039] (Z) is the use of energy from the transformation of coffee grounds for to meet the needs of the processing structure

Claims

Demands

1. The coffee grounds treatment process (A) is characterized in that upon receipt the coffee grounds (B) are treated and transformed according to at least one of the following two distinct and independent processes: by methanation (C) into biogas (D) and digestate-fertilizer (E), or, first after drying (K) into coffee grounds residue (L), then by extraction with supercritical CO2 (M) and pelletization-granulation (O) into granules (P) and bioactive components (N), finally by pyrolysis (R) into biochar (S) and electrical and thermal energy (T).

2. The process according to claim 1 is characterized in that the components (D), (E), (L), (H), (L), (P), (T) obtained at each transformation step (C), (K), (F), (M), (O), (R), are reused for the next transformation treatment step.

3. The process according to claims 1 and 2 is characterized in that the biogas (D) from the methanization of coffee grounds (C) is transformed (F) into biomethane and into thermal or electrical energy (H) and used either to supply by injection (J) the electricity and gas networks or to satisfy (Z) the energy needs of the coffee grounds processing structure (A).

4. The process according to claims 1 and 2 is characterized in that the digestate, ''fertilizer''(E) from the methanization of coffee grounds (C), is used to extract (G) undegraded organic matter such as lignin or mineral matter (I).

5. The process according to claims 1112 is characterized in that the coffee grounds residue (L) after drying (K) are used to extract by supercritical CO2 (M), active ingredients such as antioxidants (N), and after extraction of the active ingredients, for shaping the granules (P) by granulation (0).

6. The process according to claim 11 is characterized in that the coffee grounds granules (P) from the granulation (0) are used to be transformed by pyrolysis (R) into biochar (S) and electrical and thermal energy (T)

7. The process according to claim 11 is characterized in that the thermal or electrical energy (T) produced during the pyrolysis (R) of the coffee grounds granules (P) is used either to power by injection (U) the electrical networks either to satisfy (Z) in energy the needs of the coffee grounds processing structure (A).

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