BIOGAS REFINING AND BIOMETHANE PRODUCTION UNIT

Abstract

The invention relates to an integrated set of equipment and a process for treating and refining highly contaminated biogas for the purpose of producing biomethane and to the supply thereof in small volumes of up to 10 m3/h to vehicles, such that the refining unit produces small quantities of biomethane per day to supply motor vehicles operating on the same premises as those where the biogas is produced, such as rural properties and small effluent treatment stations. The unit for refining biogas and supplying biomethane, referred to herein as a biomethane microstation, is an innovative technological concept wherein the microstation comprises the generation of the fuel and the distribution thereof for consumption on the same premises, using a compact biogas refining unit.

Claims

1. A BIOGAS REFINING AND BIOMETHANE PRODUCTION UNIT, comprising a biogas compressor (73) with a biogas inlet (74) which compresses the biogas for a CO.sub.2 and H.sub.2S absorption tower (01), a siloxane absorption tower (02), a desorption tower (03), an oxy-catalyst adsorption tower (04), as well as comprising a water tank (05), with a cooling tower (06), a biomethane dryer (07), resulting in biomethane outlet (71), CO.sub.2, H.sub.2S and siloxane outlet (09), wherein the entire refining unit is controlled by an electrical panel (72).

2. A BIOGAS REFINING PROCESS, comprising the following process steps: 1. BIOGAS available for the process is compressed by a biogas compressor (73) according to its composition, with a stabilized pressure; 2. Pressurized BIOGAS is sent to a cooling tower (06) where the temperature of the water used in the process and the temperature of the gas are calibrated and stabilized according to its composition. 3. The gaseous compound (biogas) is sent to a CO.sub.2 and H.sub.2S absorption tower (01), where the removal of CO.sub.2carbon dioxide and H.sub.2SHydrogen Sulfide Gas occurs, using only water as a solvent. 4. BIOMETHANE is sent to an adsorption tower with Oxy-catalyst (04), preventing the passage of any trace of H.sub.2SHydrogen Sulfide Gas not detected by the operating sensors. 5. BIOMETHANE is sent to a SILOXANE absorption tower (02) where SILOXANE removal occurs, the SILOXANE absorption tower (02) will only be installed in the unit when BIOMETHANE is contaminated with this agent; 6. BIOMETHANE is sent to a drying system, removal of excess moisture is carried out; 7. BIOMETHANE is pressurized and stored according to all safety standards, in storage tanks (08), and is ready for use in motor vehicles; 8. BIOMETHANE is supplied in motor vehicles using the same technologies available for supply of vehicles with CNG compressed natural gas.

3. The PROCESS FOR BIOGAS REFINING AND BIOMETHANE PRODUCTION of claim 2, wherein stabilized pressure of the biogas is in the range of 1 to 35 bar;

4. The PROCESS FOR BIOGAS REFINING AND BIOMETHANE PRODUCTION of claim 2, wherein the temperature of the cooling water used in the process and the temperature of the biogas to be stabilized is in the range of 1 to 30 degrees centigrade.

5. The PROCESS FOR BIOGAS REFINING AND BIOMETHANE PRODUCTION of claim 2, wherein the contaminants removed are released and processed in other industrial applications.

6. The PROCESS FOR BIOGAS REFINING AND BIOMETHANE PRODUCTION of claim 2, wherein the water used in the process is regenerated continuously and its replacement is minimal, caused by natural evaporation.

7. The PROCESS FOR BIOGAS REFINING AND BIOMETHANE PRODUCTION of claim 2, wherein all stages of the process are controlled by a set of sensors that are monitored by a supervisory software.

8. The PROCESS FOR BIOGAS REFINING AND BIOMETHANE PRODUCTION of claim 2, wherein it processes volumes of 1 to 10 m3 per hour of biogas.

9. The PROCESS FOR BIOGAS REFINING AND BIOMETHANE PRODUCTION of claim 2, wherein the output of the biomethane from the CO.sub.2 and H.sub.2S adsorption tower (01) is monitored by sensors that detect the presence of Hydrogen Sulfide Gas and when a level higher than 0% is found, the process is interrupted.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The attached drawings and the detailed description that follows are merely presented as an example, because said biomethane microstation can be conceived through other known engineering solutions. Therefore, specific structural and functional details disclosed herein should not be interpreted as a limitation, but only as a basis for the claims; acting as a representative basis for teaching the person skilled in the art to employ and realize the development of the biomethane microstation, described herein, based on the constructive disposition henceforth detailed.

[0029] FIG. 1 shows a perspective of the biomethane microstation

[0030] FIG. 2 shows the biomethane microstation in a floor plan.

[0031] FIG. 3 shows a top view of the biomethane microstation

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0032] The biogas refining and biomethane production unit described herein is characterized by having a CO.sub.2 and H.sub.2S absorption tower (01), a siloxane absorption tower (02), a desorption tower (03), an oxy-catalyst adsorption tower (04), a water tank (05), a cooling tower (06), a cooling tower (06), a biomethane dryer (07), a biomethane outlet (71), a CO.sub.2, H.sub.2S and siloxane outlet (09), an electrical panel (72), a biogas compressor (73)

[0033] The biogas refining and biomethane production unit is characterized in that it comprises the following process steps: [0034] 1. BIOGAS for the process is available at the biogas inlet (74), enters the biogas compressor (71) and is compressed according to its composition, with a stabilized pressure within the range of 1 to 35 bar, which ensures high efficiency in all subsequent steps of the process. [0035] 2. Pressurized BIOGAS is sent to cooling tower (06) where the temperature of the water used in the process and the temperature of the gas are calibrated according to its composition. The stabilized temperatures, within the range of 1 to 30 Centigrade, guarantee high efficiency in all stages of the process. [0036] 3. The gaseous compound (biogas) is sent to the CO.sub.2 and H.sub.2S absorption tower (01), where the removal of CO.sub.2carbon dioxide and H.sub.2Shydrogen sulfide gas occurs, using only water as a solvent. It results in biomethane. [0037] 4. Only aiming to ensure the total safety of the process in a critical mission analysis, BIOMETHANE is sent to the adsorption tower with Oxy-catalyst (04), whose objective is to prevent the passage of any trace of H.sub.2Shydrogen sulfide gas not detected by the operating sensors.

[0038] The output of the adsorption tower biomethane is monitored by sensors that detect the presence of hydrogen sulfide gas. When a level greater than 0% is found, the process will be interrupted in order to adopt corrective measures. [0039] 5. BIOMETHANE is sent to the SILOXANE Absorption Tower (02) where SILOXANE removal occurs. The SILOXANE absorption Tower (02) will only be installed in the unit when BIOMETHANE is contaminated with this agent; [0040] 6. BIOMETHANE is sent to a dryer (7) to remove excess moisture; [0041] 7. BIOMETHANE is pressurized and stored according to all safety standards, in storage tanks (08), and is ready for use in motor vehicles; [0042] 8. BIOMETHANE is supplied in vehicles using the same technologies available for supply of vehicles with CNG compressed natural gas.

[0043] In the first phase of the process, listed above, the biogas compression is calculated according to its composition. The composition of biogas available for the process has several contaminants (CO.sub.2, H.sub.2S, siloxanes, particulates, moisture, etc.) that vary according to their origin. Said origin may be livestock activities, with emphasis on swine farming, milk and beef cattle, animal manure, vinasse, bagasse and sugarcane leaves, landfills and sewage treatment plants, food/agroindustrial, agricultural and/or forestry production waste. According to its biogas composition, the stabilized pressure of biogas is in the range of 1 to 35 bar.

[0044] In the second phase of the process above, the biogas temperature is calculated according to its composition, wherein the temperature of the cooling water used in the process and the temperature of the biogas are stabilized within the range of 1 to 30 centigrade

[0045] At the end of the treatment and refining stages, all contaminants are removed, in particular CO.sub.2, H.sub.2S, and SILOXANES released at the O.sub.2, H.sub.2S and Siloxane outlet (09), to be processed and economically appraised for industrial applications.

[0046] The water used in the process, stored in the water tank (05), is continually regenerated and its replacement is minimal, caused by natural evaporation.

[0047] All stages of the process are controlled by an electrical panel (72), a set of sensors that are monitored by a supervisory software, in the occurrence of non-conformity, in case of distortion in the established parameters, the process is stopped until the problem is solved.

[0048] Biomethane generated in the microstation has industrial application, having as its target public:

[0049] AGRICULTURE: Farmers who have biodigesters installed in their properties and already produce biogas, burn it, or use it for electricity generation. They may be, or intending to employ small volumes of this biogas to supply light vehicles for personal transport, as well as dedicated fleets such as animal transport, fodder distributors, milk collectors and agricultural equipment, tractors, harvesters, self-propelled sprayers and other equipment used in rural areas;

[0050] URBAN CENTERS: It has application in activities that produce biodigestible organic solid waste or have easy access to them. Also in locations presenting additional costs to be employed correctly; such as restaurants, hotels, hospitals, industrial kitchens, among other activities. Especially if they have dedicated fleets for transportation of personnel and goods (delivery) presenting ideal space conditions for the installation of biodigesters and the microstation;

[0051] Private or public sewage treatment plants: small-sized treatment plants, that produce biogas in small quantities in their proceedings, can provide biomethane for the supply of small fleets (cars, ambulances, etc.).

[0052] This biogas refining and biomethane supply unit in a microstation was developed in synergy with the global trend called zero residue, i.e. recycling, reusing and/or elimination of waste produced by human activity. This trend reinforces the concept of repurposing environmental liabilities, that is, that which is considered waste or environmental problem can become a product with income generation and reduction of environmental impacts.

[0053] Another global trend, which has also guided modern initiatives of sustainable development, as intended with the micro station is the concept of Circular Economy. This is based on the idea that all components produced within a system, even if expired or disposable, should be recycled and reused by the system itself, thus reducing the losses occurring in Linear Economy systems.

[0054] Yet another global trend that is in the conceptual base for the Microstation is the concept of Local Economic Development-DEL, which began in Seville-Spain in order to give more competitiveness to the concept of territory, taking over the world and amassing thousands of supporters. Through DEL, natural resources, notably those in decentralized or local situations, must necessarily integrate development projects.

[0055] On the other hand, the biodigestion processes used in the treatment of waste generated by human activities, make biogas available, its use as energy (electric, thermal and vehicular) contributing to the reduction of environmental impacts, namely climate change caused by emissions of greenhouse effect gases to the atmosphere, such as water and soil pollution caused by the accumulation of organic matter in the environments.

[0056] The biogas refining and biomethane production process described herein makes it so that biomethane can be used to supply vehicles, a totally renewable and virtually free gas, as it comes from treatment of waste/organic residue.

[0057] Refining biogas makes it possible to use the biomethane derived from it, reducing the risk of any environmental impact or damage to vehicles. For this to be possible all material used or waste generated in the process can be recycled and disposed of commercially, this being one of the main advantages in relation to existing processes.