DE2635026A1 - Beer brewery wort boiling system - which saves heat energy by heating lower pressure stages with vapour from higher pressure stages - Google Patents

Abstract

The wort in beer breweries is boiled at different pressure stages. Only the pressure cooker of the highest pressure stage is heated by extraneous energy (steam, hot water, hot oil, furnace) which is adequate to cover the heat losses and to heat the wort to boiling temp. Enough water is evaporated here to supply all lower pressure stages with heat by condensation of the steam. Arrangement recovers all heat from the condensation of vapours. The heat energy consumption for the brewing vat can be reduced to one-third of its usual value. The pollution of the environment by brewing vat fumes is also reduced by the same amount.

Description

Process for saving energy when boiling wort in beer breweries

The invention relates to a method with which the primary heating energy use in the brewing kettle of beer breweries through partial use of vapor condensation heat can be reduced to about 1/3 of the normal value. They also fall in the exhaust air only 1/3 of the otherwise emitted aromatic vapor fumes in the brewing pan which reduces the environmental impact by just 2/3. With the currently used Brewing systems in beer breweries, the wort is poured into a wall-heated brewing pan for approx. Cooked for 1 1/2 hours in a turbulent flow. The purpose of this process is first a thickening of the wort by evaporation of about 11% of that in the wort used existing water and, secondly, a coagulation of the water present in the wort Proteins. The heat required for the evaporation of the water is in full applied by direct heating or by steam or hot water.

So far, vapor condensers are known for heat recovery, which are instilled in the steam pipe of the brewing pan and part of the vapors through Separate condensation and recover the heat of condensation in the form of warm water. The disadvantage of this process is that the water is limited to a maximum of 65 - 70 OC can be heated, while up to a temperature level of 100 OC in the brewery Anyhow there is an excess of heat that cannot be used.

In special cases, there is also an overpressure heat exchanger used parallel to the brewing kettle through which part of the wort is subjected to a strong increase in pressure is pumped. Here the wort is boiled at a high temperature, which speeds up the process which causes protein coagulation; the correspondingly heated wort is then relaxed and fed back into the brewing pan, with the superheating in evaporation power is implemented.

With the present method, the heat of vapor condensation should now partly be recovered at a high temperature level that this heat directly with Wort boiling can be reused.

This object is achieved in that the wort at different pressure levels are cooked, with the heat for the most part in evaporation power is implemented, and in each case the vapors by condensation in the next lower one Pressure stage cover their heat requirements.

For this purpose, a Teilmege is on the bottom of the brewing pan (1) near the outer edge the wort is sucked off and by a pressure booster pump to the desired boiling pressure the cooker (4.1) brought the first pressure stage.

Part of the wort at this pressure level is now diverted and passed through a heat exchanger (3.1) passed, where the countercurrent with that from the cooker (4.1) the draining wort is preheated to almost the boiling point of the digester (4.1) will. The remaining wort of the first pressure stage is from another pressure booster pump (2.2) brought to the pressure level of the next digester (4.2) and also through an upstream heat exchanger (3.2) in countercurrent with the outflowing the Wort from the digester (4.2) is preheated to almost the boiling point of this digester (4.2).

As complete a heat exchange as possible in between the incoming and outgoing Seasoning is critical to the amount of heat saved by the process, as only the Heat converted into evaporation can be used several times through vapor condensation can.

The cooker (4.2) of the highest pressure level now receives so much external energy (13) fed by steam, hot water, hot oil or direct fire that one hand the heat losses are covered and the wort flowing into the digester (4.2) is fully expanded Boiling temperature are heated and on the other hand so much water is evaporated that the subsequent stages lower pressure levels adequately with heat through condensation this Steam (5.2) are supplied. This steam is now on the heat exchanger surfaces of the cooker of the next lower pressure stage and condensed there, since the Season in this cooker because of the lower pressure level at a correspondingly lower level Temperature is boiling. The resulting heat of condensation is the same as above described to cover heat losses, to reheat the inflowing wort at boiling temperature and for the most part to evaporate water (5.1) in the Pressure level of the cooker (4.1) used up.

The condensate of the vapors (5.2) of the level above, which is in Cooker (4.1) of this pressure level occurs, is reduced to the boiling pressure by a throttle (6.3) of the cooker (4.1) relaxed, with the overheating in post-evaporation performance is implemented. In a phase separator (7) the steam is removed and the steam (5.1) of the cooker (4.1) mixed in.

The total amount of steam now obtained from the last pressure cooking stage is passed to the heat exchanger surfaces (8) of the brewing pan (1), where they are discharged their heat of condensation on the wort in the brewing pan (1).

The amount of wort pumped to the pressure cooker is to be measured in such a way that that the percentage of evaporation per wort used in each stage in a comparable Of the order of magnitude of the overall process.

Since the pressure cookers (4 ..) are small in relation to cost reasons to the brewing pan, so a large amount of wort has to be constantly pumped through this cooker in order to avoid impermissible thickening in these cookers.

The wort flowing out of the individual pressure boilers (4 ...) flows pass through the heat exchanger (3 ...), where they each have their overheating for the most part to the inflowing wort, back to the brewing pan (1), where it released shortly before entering the brewing pan by means of a throttle to atmospheric pressure will. The after the Heat exchangers (3 ...) remaining residual overheating is implemented here in post-evaporation performance. For fluidic considerations the returning wort is to be introduced from below near the central axis of the brewing kettle (1) because the re-evaporation process requires intensive boiling of the wort in the Brewing pan (1) and thus a highly desirable thorough mixing of the liquid has the consequence.

The vapors produced in the brewing pan (1) are now only in terms of quantity still make up about 1/3 of the otherwise accumulating vapors, are combined with the incoming Fresh air (10) passed through the vent pipe (11) into the open air. With help of a Vapor condenser, the heat of these vapors can optionally also be used, however, as already said above, at a relatively low temperature level.

The condensate that occurs at a temperature level of over 100 "C (9) of the various pressure levels can be used elsewhere, e.g. to heat up the lye can still be used in the bottle laundry.

The advantages that can be achieved with this process are firstly: that with any available primary energy source without significant Expenditure of mechanical energy depending on the costly use of external energy can be reduced considerably depending on the number of pressure cooking levels. Second is by boiling the wort at temperatures sometimes higher than 100 "C the protein coagulation intensified. Third, in this procedure, the largest falls Part of the odorous and therefore environmentally harmful vapors in liquid form and can can be discharged directly without spreading odor.

In addition, the re-evaporation results in the flowing back from the pressure cooking stages When introduced correctly into the brewing pan, season an intense turbulence and pressure mixing the seasoning.

The procedure is shown in the example in the attached schematic drawing represented by two pressure cooking levels. However, the number of these pressure cooking levels is Anyway starting from one and is calculated on a case-by-case basis the end the costs for the heat exchanger (3 ...) and the pressure cooker (4 ...) as well as the the heat gain saved energy costs, with increasing number of stages also increases the energy saving. In practice, given today's cost ratios a system with two pressure levels as shown results in an optimal amortization.

Claims (7)

Claims 1. A method for saving energy when boiling wort in beer breweries, characterized in that in parallel to the brewing pan, a portion of the wort circulated from the brewing kettle flowed through Pressure boiling kettles, in each case liquid is evaporated from the wort whereby the from Pumps generated wort pressure in the cookers from level to level, each set in this way that the boiling temperature of the wort in the respective pressure cooker by a few degrees is under the wort in the pressure cooker of the next higher pressure level, and that only the pressure cooker with the highest wort pressure from the outside with any quality suitable energy source is heated, while the heat exchange surfaces of the pressure cooker the next lower pressure level from the higher tension vapors of the previous one Cooker are heated, with the vapors of the last pressure cooker the jacket of the Heat the brewing pan. 2. Process for saving energy when boiling wort in beer breweries, according to claim 1, characterized in that the circuit between the brewing pan and pressure cookers, the amount of wort pumped around is large compared to that in the cookers evaporated liquid, so the ratio of evaporated liquid per unit of time to added wort per unit of time is in the same order of magnitude as the corresponding relationship in the overall process. 3. Process for saving energy when boiling wort in beer breweries according to claim 1, characterized in that the wort flowing into the digester in a heat exchanger in countercurrent, the overheating heat related to the 100 "C temperature level absorbs the wort flowing back to the brewing pan and cools the latter down accordingly, so that in the respective cooker apart from the heat losses just a small one Part of the amount of heat supplied to this cooker to heat the wort and as much as possible Share can be used for liquid evaporation. 4. Process for saving energy when boiling wort in beer breweries, according to claim 1, characterized in that the respective pressure cooker via the intermediate heat exchanger, wort flowing off directly from each pressure stage is returned to the wort kettle, where it was shortly before atmospheric pressure is relaxed. 5. Process for saving energy when boiling wort in beer breweries, according to claim 1, characterized in that the to be pumped to the pressure cooker Wort is sucked off at the bottom of the brewing pan near the outer edge and at the bottom of the Brewing pan near the center is fed back in an upward direction. 6. Process for saving energy when boiling wort in beer breweries, according to claim 1, characterized in that the Iloch pressure vapor condensate of all Pressure cooking stages with the exception of the last stage, each based on the pressure of the vapors the stage in which they were condensed, with the relaxation resulting steam are mixed with the vapor of the same pressure, while the condensate is added to the condensate of this pressure level. 7. Process for saving energy when boiling wort in beer breweries, according to claim 1, characterized in that the expanded condensate is the lowest Pressure stage and the condensate of the same pressure of the brewing pan heating no further be relaxed, but at the given pressure and temperature level more Used e.g. in the bottle laundry.