FI113627B - Aggregates for pressure coating of biogas - Google Patents

Description

113627

BACKGROUND OF THE INVENTION Technical Field The present invention relates to a biogas pressurization apparatus.

Biogas can be produced, for example, from biogas reactors separate from sewage and sludge from farms and communities. It can also be collected from, for example, landfills where decomposing organic waste has been removed.

Biogas generally contains 30-50% by volume of carbon dioxide, whereby even the removal of partial carbon dioxide 10 significantly reduces, for example, the space required for gas storage. The efficiency of biogas combustion will also be improved if the carbon content of the biogas is low. Biogas generally also contains other compounds, such as hydrogen sulphide, which make it more difficult to use biogas or cause corrosion, for example.

The use of biogas is also generally hindered by its low production and collection pressure. It can be used on site eg in boilers and aggregates, but. eg in vehicles it is often unprofitable to use high pressures. ': *. cost and storage costs.

· 'The biogas is pressurized e.g. with high pressure compressors such as water ring compressors. The biogas can also be pressurized and purified, for example, with column washers, which • can raise the biogas pressure to about 10-40 aty. The problem with these:, # ,: devices is eg. the fact that they are either physically large or technically very complex. In this case, the equipment is very expensive, especially if a pressure of, for example, 100 - '·, · 200 aty is sought.

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BACKGROUND OF THE INVENTION A biogas pressurization apparatus has now been invented which is technically extremely simple and compact.

* · * · · '··. To achieve this object, the invention is characterized by the features set forth in the independent claims. Other claims disclose some preferred embodiments of the invention.

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Not only can the biogas be pressurized, but it can also be purified using the pressurizing apparatus according to the invention using, for example, water as a washing liquid. If necessary, the washing compounds or substances may be added to the water.

The pressurization apparatus according to the invention comprises at least a biogas feed pipe 5 with an overpressure device, a biogas outlet pipe, a wash water supply pipe with an overpressure device and an atomizer, and a wash water outlet pipe with a carbon dioxide removal unit. In addition, shut-off valves and non-return valves required for the operation of the process are connected to the pressurization equipment. The operation of the pressure equipment is controlled, for example, by means of limit switches or a balance.

10 The pressurized equipment containing the biogas is supplied with pressurized wash water through a nebulizer. As the water level reaches the upper control line in the pressurizing apparatus, the valve for the biogas outlet is opened and the washed biogas flows out of the pressurizing apparatus. When the water level reaches the upper limit, the shut-off valve on the biogas outlet is closed, the wash water supply is stopped, the wash water outlet valve is opened, and 15 pressurized biogas are fed to the pressurizing equipment. When the water level reaches the upper limit, the shut-off valve on the biogas outlet can either be closed or left open. When the water level reaches the lower control line, the wash water outlet valve is closed and the biogas feed pipe valve is closed. The cycle described above is then repeated.

... # 20 The scrubbing water is led from the carbon dioxide scrubber of the scrubbing pipe to the high pressure inlet pipe and the scrubber. If necessary, some of the wash water is replaced with new wash water. For example, a detergent dosing device can be connected to the washing water pipes.

* * | The pressurized and purified biogas leaving the pressurization system can be derived. 25 through one or more dryers, for example to pressure tanks or biogas containers.

Purified biogas needs a separate storage compartment, as it is usually not a good idea to mix it with unpurified biogas. In the biogas container according to the invention, the purified and / or dried biogas can be stored e.g. in the upper or second upper part. At the same time, the dried biogas provides an effective Ηχηροί 30 insulation for the entire biogas container.

The equipment used for purifying and pressurizing biogas is technically very simple and economical and safe to use. The biogas can advantageously be supplied, for example, from 1 to 100 cc, such as 1 to 50 cc, 1 to 10 cc, 5 to 15 cc, 5 to 50 cc or 50 to 100 cc. n, pressurized to the pressurization apparatus and pressurized by 3 113627 with pressurizing apparatus e.g. 20 to 300 aty, such as 20 to 50 aty, 50 to 100 aty, 100 to 300 aty, 100 to 200 aty, or 200 to 300 aty, to pressure.

The pressurization apparatus according to the invention has only two pumps. Both of these may advantageously be gas-powered gas compressors and water compressors, which are already commonly used in industry or on farms. This contributes significantly to the economics of the invention.

Maintenance of the apparatus according to the invention is also advantageous. For example, maintenance and kiosk costs for bulk production equipment are generally low.

Biogas can advantageously be pressurized to a pressure of 100-300 IU using a very simple technical apparatus, and at the same time the carbon dioxide, particles and hydrogen sulphide are removed from the biogas. Since, for example, the solubility of carbon dioxide depends on the pressure of the washing water used, the apparatus according to the invention provides a good carbon dioxide removal due to the high pressure used.

It is also advantageous to use unrefined overpressure bio-15 gas in the pressurization apparatus to displace the wash water, since this prevents the carbon dioxide of the wash water from being released in the pressurizing plant. The carbon dioxide can be removed from the scrubbing water in a carbon scrubber unit connected to the exhaust pipe where the pressure of the scrubbing water is lowered close to the ambient pressure. This will quickly and efficiently release carbon dioxide from the wash water. Preferably, the carbon dioxide-purified wash water can be returned to the pressure wash device.

t I • ·: '\ The pressurization equipment can be manufactured in different sizes. It can be made into small single, ·. ropes for eg farms and large units eg for wastewater treatment plants. It can also be made into portable models that can be used to pressurize biogas from farm gas storages, for example.

The apparatus according to the invention can be controlled either by automated and / or manual control apparatus to carry out the cycle required for pressurization.

Specific Description of the Invention

In the following, some embodiments of the invention will be described in detail with reference to the accompanying drawings.

Fig. 1 shows a pressurizing device for pressurizing biogas.

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In Fig. 1, the pressurizing apparatus 201 for cleaning biogas 210 includes a biogas feed pipe 211, a biogas outlet pipe 221, a wash water feed pipe 231, and a wash water outlet pipe 241. A return valve 212 and a biogas dryer 300. A water compressor 232 is connected to the wash water supply pipe 231 and a nebulizer 202 within the pressure equipment 201. A shut-off valve 242 and a carbon dioxide removal unit 243 are connected to the wash water outlet pipe 241.

The apparatus of Figure 1 can pressurize and purify biogas 210, e.g. opening the shut-off valve 223 of the biogas outlet pipe 221, whereby the purified biogas 220 flows into the biogas outlet pipe 220 - the water surface VP of the pressurizing equipment 201 reaches the upper limit VPyr the shut-off valve 242 of the washing water outlet pipe 241 After the VP has lowered to the lower limit VPAR, the shut-off valve 242 of the drainage pipe 241 is closed and the biogas 210 is supplied. 'Will be terminated.

As the water surface VP of the pressurizing apparatus 201 reaches the upper limit, the supply of the wash water 230 to the VPYR can be stopped and the shut-off valve 223 of the biogas outlet pipe 221 is closed. 25, the shut-off valve 242 of the wash water outlet pipe 241 is then opened. Can also be

; making the water surface VP of the pressurizing apparatus 201 rise to the upper limit VPYR

the supply of wash water 230 is left on, the shut-off valve 223 of the biogas outlet 221 is closed, and thereafter the shut-off valve 242 of the wash water outlet 241 is opened. This can be done, for example, when the outlet pipe 241 and the corresponding shut-off valve 242 are large enough to discharge the washing water 230 which accumulates in the pressure vessel.

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The wash water 240 of the outlet pipe 241 is provided or discharged to the carbon dioxide removal unit 243, where the carbon dioxide 250 in the wash water 240 is released as a result of the pressure drop. Purified or new washing water 260 is then supplied to the pressure compressor 231. Part of the purified washing water 260 may be discharged through the outlet 261, e.g., into the sludge in the biogas vessel 1, 101. On the other hand, purified wash water 260 may be supplied with new wash water 270 by means of line 271 and detergent 280 by line 281.

The pressurized and purified biogas 220 may be introduced into the biogas vessel 1, 101 or to a separate storage pressure vessel 401 either directly or in the dryer 301 as dried biogas 290.

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Claims (9)

1. Biogas pressure coating assembly, characterized in that the pressure coating assembly (201) used for biogas pressure coating (210) has: - a tube (211) for supplying biogas, which tube has at least one device (213) ) for supplying biogas, - a pipe (221) for removing biogas, which pipe has at least one shut-off valve (223), - a pipe (231) for supplying wash water, which pipe has at least one spray nozzle (202) and a pressure washer (232) for the wash water; 10. a pipe (241) for removing the wash water, said pipe having at least one shut-off valve (242) and a unit (243) for removing carbon dioxide, and which has been controlled according to the following cycle: the pressure coating assembly (201), which contains biogas (210), has been fed to wash water (230) which underpressures, via the spray nozzle (202) of the wash tube (231) by means of the overpressure device (232) of the wash water. - when the water surface (VP) of the pressure coating unit (201) has risen to an upper • control limit (VPYo), the shut-off valve (223) of the biogas outlet pipe has been opened • ♦, (221), whereby purified biogas (220) has flowed into the biogas outlet. • * · flow pipe (221), • · φ · 20. When the water surface (VP) of the pressure coating assembly (201) has risen to the upper limit (VPYR), the shut-off valve (242) for the wash water outlet pipe • · · (241) is opened, • · »- in the pressure coating assembly (201), biogas (210) has been supplied under overpressure :: via the biogas supply pipe (211),» I • · · 25. where the water surface (VP) of the pressure coating assembly (201) has dropped to the * · ”* lower limit (VPar) the valve (242) for the outlet water (241) of the wash water has been closed. »· Pressure coating assembly according to claim 1, characterized in that biogas (210) has been supplied with the device (213) for supplying biogas under 1 - 50 atmospheres pressure. 113627 Pressure coating assembly according to claim 1 or 2, characterized in that the wash water (230) has been supplied with the overpressure device of the wash water (232) under the pressure of 20-300 aty. Pressure coating assembly according to any of the above claims, characterized in that one or more dryers (301) for the biogas (220) have been coupled to the pressure coating assembly (201). Pressure coating assembly according to any of the above claims, characterized in that one or more storage pressure receptacles (401) for the biogas (220, 290) have been connected to the pressure coating assembly (201). 10 6. A method for pressurizing biogas, characterized in that a pressure coating assembly (201) is used for pressurizing the biogas (210) which shows: - a tube (211) for supplying biogas, which tube has at least one device (213) for supplying biogas, 15. a pipe (221) for removing biogas, said pipe having at least one shut-off valve (223), - a pipe (231) for supplying washing water, said pipe having at least one spray nozzle ( 202) and an overpressure device (232) for the wash water; - a pipe (241) for removing the wash water, said pipe having at least one: 20 shut-off valve (242) and a unit (243) for removing carbon dioxide; ; ': And which is controlled according to the following cycle: · · · · · · - in the pressure coating assembly (201), which contains biogas (210), measuring wash water (230) which under pressure is pressurized via the spray nozzle of the washing tube (231), · · ·. (202) by means of the wash water overpressure device (232), 25. When the water surface (VP) of the pressure coating assembly (201) has risen to an upper control limit (VPyo), the shut-off valve (223) opens to the biogas outlet pipe (221), whereby the purified biogas ( 220) flows into the biogas outlet pipe (221), 113627 - when the water surface (VP) of the pressure coating assembly (201) has risen to the upper limit (VPyr), the shut-off valve (242) of the wash water outlet pipe (241) is opened, ) measure biogas (210) under pressure via the biogas supply pipe (211), - when the water surface (VP) of the pressure coating unit (201) has dropped to the lower limit (VPar), the valve (242) for the wash water outlet pipe (241) is closed. Process according to claim 6, characterized in that when the water surface (VP) has risen to the upper limit (VPyr), the feeding of the wash water (230) is terminated. Method according to claims 6-7, characterized in that the wash water (230) is measured with the overpressure device of the wash water (232) under pressure of 20 - 300 atm. Method of manufacturing a biogas pressure coating assembly, characterized in that the pressure coating assembly (201) is coupled to: 15. a tube (211) for supplying biogas, said tube having at least one device (213) for supplying biogas A pipe (221) for removing biogas, said pipe having at least one shut-off valve (223), - a pipe (231) for supplying washing water, said pipe having at least one spray nozzle (202) and an overpressure device (232) for the wash water; - a pipe (241) for removing the wash water, said pipe having at least one shut-off valve (242) and a unit (243) for removing carbon dioxide; a manually and / or automated controlled control device, in which: (202) by means of the wash water overpressure device (232), t - where the water surface (VP) of the pressure coating assembly (201) has risen to an upper control limit (VPY0), the shut-off valve (223) opens to the biogas outlet pipe (221), whereby the purified biogas (220) flows into the biogas outlet pipe 30 (221), 113627 - when the water surface (VP) of the pressure coating assembly (201) has risen to the upper limit (VPyr), the shut-off valve (242) of the wash water outlet pipe (241) is opened in the pressure coating (201) measure biogas (210) under pressure via the biogas supply pipe (211), - as the water surface (VP) of the pressure coating unit (201) has dropped to the lower limit (VPAr), the valve (242) for the wash water outlet pipe (241) is closed. »I • t» I »» t • · I • Ψ »• · · •» • · • · * • · • »• · · • · * * * • · •> • IIII • • * • ·>» 11 (1