EP3174831A1

EP3174831A1 - Method and device for treating liquid manure and fermentation remains

Info

Publication number: EP3174831A1
Application number: EP15745148.5A
Authority: EP
Inventors: Hermann-Josef Wilhelm; Karl Michael Schmidt; Hanspeter MAAS
Original assignee: Agriv Raiffeisen Eg
Current assignee: Agriv Raiffeisen Eg
Priority date: 2014-07-28
Filing date: 2015-07-20
Publication date: 2017-06-07
Also published as: WO2016015839A1; DE102015001859A1

Abstract

The invention relates to a method and a device for treating liquid manure and fermentation remains, according to the preambles of patent claims 1 and 12. To achieve the effect here that the so-called precipitation and separation of the liquid manure or the fermentation remains into a floc phase or thick phase and into a clear phase or thin phase takes place much more quickly and effectively, it is proposed according to the invention that the sedimentation tank is preceded by an upright precipitation tank, in which the liquid manure is introduced at the bottom and with turbulence, and a precipitating agent is continuously injected at the same time, and likewise at the bottom, into said turbulence of the liquid manure introduced, with the effect that the mixture of liquid manure or fermentation remains together with the injected precipitating agent rises upwards and expands in the precipitation tank, and so is discharged from the top of the precipitation tank and introduced into the sedimentation tank.

Description

Process and equipment for the treatment of agricultural manure and digestate

The invention relates to a method and a device for the treatment of agricultural manure and

Digesting, in which the manure or the digestate- a precipitant added, and then with water as a release agent in a Äbsetzbehältnis a thick or flake phase of a clear or thin phase

is separated, according to the preamble of claims 1, and 12th

By definition, agricultural manure should comprise all feces from animal husbandry, including manure. In addition, fermentation residues should also be precipitated in the invention. Fermentation residues include fermentation residues

Biogas plants, fermentation residues from the ethanol production, as well as fermentation residues from the food and food production, seepage juices from silage facilities and digestate storage facilities. The precipitation process in the separation of

Agricultural manure in a thick or flake phase and in a thin or clear phase often creates the problem of adequate separation of said flake phase from the clear phase. The flakes are very Fragile and form in the precipitation, among other things, from dissolved ingredients of manure or digestate. Since the chemical precipitation with the addition of precipitant is relatively fast, it also depends on the

physical treatment of the flake phase following the precipitation in order to efficiently separate the said, forming phases from each other. Thus, in the further separation to prevent mechanical shearing of the flakes, because otherwise such fragments again tarnish the clear phase or can go into redemption.

The invention is therefore based on the object, a method, and a device of the generic type to the effect that the so-called precipitation and separation of manure or digestate in a flock or thick phase and in a clear or thin phase much faster and more effective, and for the flakes formed by precipitation runs gently.

The object is achieved in a method of the generic type according to the invention by the

characterizing features of claim 1 solved.

Advantageous embodiments of the invention

Application are in the dependent claims 2 to

11 indicated.

With regard to a device of the generic type, the object is achieved by the characterizing features of claim 12.

Further advantageous embodiments of the device are specified in the remaining claims.

Other uses of the invention are in the

Claims 19 and 20 indicated. The core of the method according to the invention is that the settling tank is preceded by a precipitation vessel to be filled from bottom to top into which the liquid manure or fermentation residue is introduced at the bottom and swirling, and also with a precipitating agent directly on the bottom side directly into said turbulence of the introduced liquid manure or digestate is injected, such that the mixture of manure or digestate together with the injected precipitant in the precipitation container is ascending and expanding so that it flows out of the top of the precipitation vessel and into the

Settling container is initiated.

In a further advantageous embodiment

indicated that the precipitation tank a

cylindrical, upright form, which is filled from bottom to top. In this way, in the manner according to the invention when introducing a

Vortex, but as will be further illustrated, the vortex remains limited to the point of introduction.

This achieves the following effect. in the

Introductory area, the introduced slurry still rotates. In the vortex then the precipitant

injected, thereby resulting in an optimal mixture of the precipitating agent with the manure / digestate. The precipitation reaction proceeds extremely fast, i. in a few seconds or even less than a second. At the same time, the flocs produced by the precipitation float upwards as foam. It can be seen that the manure only rotates near the bottom of the precipitation tank, but above the foam floats up completely without rotation, and expands from the

Discharge of the precipitation tank into the settling tank. Shear forces on the flakes are considerably reduced.

In an advantageous embodiment it is stated that in the vortex in the bottom region of the precipitation container

introduced liquid manure or digestate in the same direction of the swirling acidified water is introduced. The forming vortex or vortex with a

constant rotation can be generated, for example, by an introduction of the manure by these eccentric, i. to the vertical central axis of the upright

Precipitation container is introduced eccentrically.

In a further advantageous embodiment, it is provided that the acidified water, at the anode of a

Electrolysis reaction of salts in water withdrawn water, the so-called anolyte.

Acidified water is thus said anolyte or a mixture of anolyte and water. When

Precipitant is at the illustrated here

Precipitation process ferric chloride, in particular

EisenlllChlorid used.

This has the opposite of all other metal salts

Advantage that iron and iron compounds, such as

Iron hydroxide arise, which are of considerable advantage in a post-fermentation of the thick or flake phase in a Nachvergärungseinrichtung a biogas plant, because they support the gas drive.

Optionally, to acidify the water may also be acetic acid, or propionic acid, or sulfurous acid, or

Citric acid or lactic acid can be used. The advantage of these variants is that these too in a return of the flocculent or thick phase in a fermentation room or Nachvergärräum a biogas plant the Support biogas-driving microbiology.

The said acidic anolyte acts thereby chemically so by, among other things, with the iron-containing

Hemoglobin disintegrates from the animal manure in the same precipitate. This in the way that the amount of the required said precipitating agent is thereby reduced.

In a particularly advantageous embodiment, it is stated that in the settling tank before the mixture of manure or digestate together with the injected precipitant and optionally the acidified water, a predetermined amount of water is presented, and said, transferred from the precipitator mixture from the top of the introduced water to separate the thick or flake phase of the thin or clear phase. By introducing the already precipitated in the precipitation tank manure or digestate from the top of the settling tank or on the submitted water level in the settling tank, a floating of the flock phase is physically significantly favored and supports the separation of flake phase and clear phase.

An introduction of the precipitated manure coming from the precipitation tank / digestate directly below the

Water level of the water introduced in the settling tank, would break up the fragile flakes again and bring back parts of the flocks produced by precipitation. Exactly this is avoided by the inventive introduction to the water level of the water introduced in the settling tank.

The settling tank expands the floating

Flake phase and can be abgeskimmt above. heavier On the other hand, particles sink downwards and can be withdrawn as sediment or sedimentation sludge in the sedimentation tank at the bottom, for example by an oblique bottom shape with a conical taper of the soil along a depression provided with a screw conveyor, then the sediment or sludge from the settling tank can transport.

In a further advantageous embodiment, it is stated that the precipitation container is an upright

cylindrical container is, and that said

Turbulence through a cylinder to the longitudinal axis

eccentric placed introduction for manure / digestate is generated.

Alternatively, said turbulence may be generated by a rotating element. this is a

Alternative to the eccentric introduction of

Manure / digestate. But it can also be done together with the eccentric introduction of manure / digestate, if it is, for example, very heavy gullies / fermentation residues with a higher content of dry matter.

In a further advantageous embodiment, the settling in the settling flocculent or thick phase forming can be removed by skimming or pushing off, and the remaining thin or clear phase be further clarified by the addition of milk of lime or dilute potassium hydroxide solution and withdrawn as nutrient for plant crops.

In a further advantageous embodiment, it is stated that the precipitant optionally at different

Injection points of the precipitation container is or can be initiated, which are arranged at different heights, measured from the bottom of the precipitation container, such that the effectiveness of the precipitation different rotational speeds and / or

Viscosities of different gullies to be precipitated is customizable. The speed of rotation depends on the diameter of the precipitation tank and the pumping capacity with which the liquid manure or the fermentation residues in the

Be pumped precipitation tank. Of course, also from the viscosity. By placing different

optional connection flanges for precipitants in the

Precipitation tanks at different heights, the material flow with regard to an optimal mixture of any gullies and fermentation residues with precipitant is taken into account. So is dependent on the respective manure or digestate that connection flange with a

Precipitant injector providable, the most optimal injection of precipitant in the Stoffström

guaranteed.

In a further advantageous embodiment, it is stated that a further optional inlet opening of liquid manure and / or water and / or anolyte and / or catholyte and / or precipitant is provided in the bottom of the precipitation vessel, via which without rotation of one of said media can be introduced.

With regard to a device according to the invention it is stated that the settling tank is preceded by a precipitation tank, which is to be filled from bottom to top, in which the liquid manure or fermentation residues can be introduced at the bottom by means of an inlet flange, and also directly into the said turbulence of the introduced bottom side Manure or digestate a precipitant is continuously injected through an injection with such a way that the mixture of manure or digestate together with the injected precipitant in the precipitation container is ascending and expanding upwards so that it flows out of the top of the precipitation container from a discharge and in the settling container can be introduced. When ascending is, as already described above, the floating

Flake foam completely spin-free while under the

Flake foam rotates or turns the introduced slurry or digestate.

The fact that the floating flake foam no longer rotates, this can upward through the conically tapered Ausleitöffnung out according to the requirements of the

Gently flow out of the equation of continuity, and into the

Flow in settling tank. In the precipitating tank thus runs the pure chemical precipitation and in the settling tank is essentially the physical separation of thick or

Flake phase from the thin or clear phase.

In a further advantageous embodiment, therefore, as stated above, indicated that the precipitation container is provided for discharge with a tapered and funnel-shaped in flow cross-section tapered pipe section, and that the discharge itself with a

Pipe connection flange is provided.

Furthermore, it is advantageously designed that the

Precipitation container is an upright, to be filled from bottom to top cylindrical container, and that the said turbulence by an eccentric to the vertical cylinder axis and placed on the bottom side

Inlet opening for manure / digestate is generated. In this way, the said vortex is generated in the bottom region of the precipitation tank, which causes a good mixing of the incoming manure or digestate with the acidified water and the precipitant.

In a further advantageous embodiment it is stated that also eccentrically to the said vertical cylinder axis on the bottom side, a further opening for the introduction of

Precipitant is arranged. In a further advantageous embodiment is stated that also eccentric to the said vertical

Cylinder axis on the bottom side another opening to

Initiation of acidified water or acid is arranged. This leads to an optimal mixing of said components and to an optimum

Precipitation result.

In a further advantageous embodiment it is stated that for generating a vortex at the bottom of the

Fällungsbehälters mechanically rotating means are provided, or may be provided.

In a further advantageous embodiment, it is indicated that the transition region from the output of the

Fällungsbehälters in the settling tank

is carried out by a transfer pipe, in which further injection openings are provided as flange connections through which precipitating and / or separating agents and / or surfactants are injectable before the

transferred manure or Gärrestestrom the

Settling tank reached. In this way, either a post-precipitation is possible, or the separation is more effective, or the flocculation is supported, and for example when injecting small surfactant mixtures, an effective slipping of the mass is made possible on a filter surface, thereby making any subsequent filtration more effective.

A use according to the invention results from the fact that the said precipitation vessel is used in the operation of biogas plants operated with liquid manure in order to pretreat slurry streams prior to introduction into a respective fermenter of the said biogas plants, and subsequently with the resulting flocculation phase from the liquid manure to controlled feeding the fermenter performs. Thus, in the biogas plant supplied slurry flows of Nutrient content through the said precipitation, but also a controlled desulfurization can be controlled / influenced to optimize the gas production.

A further advantageous use results from the fact that the said precipitation container in the filling of digestate or slurry storage in the flow before

Reaching the digestate or slurry storage

is interposed, for the pretreatment of the digestate or manure, for example, with iron chloride to

Hydrogen sulfide (H ₂ S) bond.

Embodiments of the invention are in the

Drawing shown and described in more detail below.

It shows:

Figure 1: precipitation container in different views

FIG. 2: Precipitation container in operative connection with FIG

Absetzbehälter

Figure 3: Perspective view of the

Precipitation container.

Figure 4: precipitation tank with optional

Inj ection connections

Figure 5: precipitation container for the use of a

Injection during the transfer of manure or fermentation

FIG. 1 shows the precipitation container 1 according to the invention in various views. The upper row of figures shows the precipitation container in different

Page views. Below, the precipitation container is shown in plan view. The precipitation container consists of an upright cylindrical vessel 2, which is provided at the top with a connecting flange 8, on which an upper funnel-shaped conical projection 3 is formed, which then opens into a discharge opening 4 above. The manure / digestate is / are introduced from below, ie through the inlet opening 5, and at the same time, the injection of the precipitant through the injection port 6 takes place.

At the injection port while the precipitant is supplied with an adjustable metering pump to adjust the precipitating agent in need exactly to the manure / digestate quantity and possibly regulate. The regulation of the precipitant feed can be made via a discharge area of the precipitated manure / digestate

Conductivity measurement done. Another

Introductory opening 7 is provided to supply, for example, water and / or anolyte, inter alia, as a separating agent.

From the plan view it can be seen that all

Inlet openings and the injection port eccentric and perpendicular to the central axis of the cylindrical

Fällungsbehälters run. This has the consequence that upon initiation a rotational movement in the mixture arises. This is according to the invention also intended to homogeneous mixing of manure / digestate with

To ensure precipitant and / or water / anolyte. The precipitation reaction takes place at the same time initiation of all these liquids immediately, and the precipitated flake phase rises as a foam crown floating in the precipitation vessel and emerges from the top

Outlet 4 off. There is, as shown schematically in Figure 2, a pipe connection provided, which then transfers the precipitated mixture or mixture in a settling and / or a filter container. The process is carried out continuously. Figure 2 shows schematically a representation in which the precipitation tank according to the invention below the manure / digestate is supplied together with the precipitant and / or with the acidified water. The chemically reacting mixture rises upwards, and is guided via the discharge opening, Figure 1 item number 4, in a knee-shaped tube, and from there up into the settling tank 10, which is provided with a sloping bottom. There it slips

Foam / manure mixture then down and floats on a water level 11 presented water in

Settling tank on. There may be presented either water, or anolyte or a mixture of both.

In quasi-continuous operation, i. at

continuous passage of manure / fermentation residues together with precipitant and / or water, now the resulting liquid level increases

Depositing container always upwards. Above

arrived, the process is temporarily stopped, and the floating flake phase top stripped with a Skimmer 12 and brought out of the settling tank 10 out. The cloudy or clear phase, and if necessary, the deposited sedimentation are then present with clear phase separation, and said phases can then be withdrawn separately, and then the process continues with a new manure / fermentation residue - batch, etc. Alternatively, the Fällungsbehälter but also be placed below the settling tank, which is structurally compact and therefore advantageous, and the transfer pipe from the upper exit of the

Fällungsbehälter flows into the settling tank on it. The transfer tube can then be provided with further connection flanges for injection of precipitant and / or water and / or anolyte and / or catholyte and / or surfactants. Figure 3 shows the precipitation container again in a perspective view. It should be noted that the precipitation container is also upright in the operation of the invention, introduced the manure / digestate below and above after the reaction

be discharged, or discharged into a spreader or immediately to a band filter.

As already stated above, the precipitation vessel can also be used in the direct operation of biogas plants. This when using with manure

operated biogas plants said

Fällungsbehälter is used to slurry in this way before introduction into a respective gene

Pre-treat fermenter of said biogas plants, and thereafter performs a controlled feeding of the fermenter with the resulting flake phase from the manure. Thus, in the biogas plant supplied slurry flows of the nutrient content can be controlled / influenced by said precipitation, but also a targeted desulfurization be made to optimize gas production.

FIG. 4 shows a side view of a

Precipitation container 1 with injection ports in the form of flanges at different heights. Depending on the viscosity and Gärbrei- or slurry consistency advantageous good mixing with precipitant is achieved in that one can adjust the injection height in the flow to the viscosity and consistency of the supplied streams by appropriate choice of one or more of the injection ports. It is important that the precipitant in the

Flow cross-section is injected in about one fifth to one third of the diameter of the precipitation vessel. FIG. 5 shows an application example for the use, for example, of an H ₂ S elimination by means of an iron chloride injection during the transfer of the liquid manure or digestate stream into a manure or fermentation residue store.

The material flow is supplied via the flange near the bottom, the said injection is carried out via the injection ports with iron chloride and the material stream is discharged at the top. The discharge pipe is formed over elbows so that the Stoffström down below the precipitation tank, on the other side of the

Discharge is discharged.

The advantage of such an arrangement is that the precipitation vessel can be built into the arrangement of pipelines at the same height therebetween.

reference numeral

1 precipitation tank

2 Cylindrical container or container part

3 Conical funnel-shaped part

4 discharge opening with flange

5 inlet for manure / digestate

6 Injection opening for precipitant

7 inlet opening for water and / or acidified Wa

8 transition flange

10 settling tanks

11 Provided water or water / anolyte level

12 skimmers

Claims

claims

1. Method of treatment of agricultural

Manure and digestate, in which the manure or

adding a precipitating agent to the digestate, and subsequently separating a thick or flake phase from a clear or thin phase with water as the separating agent in a settling tank, characterized

in that the settling tank is preceded by a precipitation tank to be filled from bottom to top, in which the liquid manure or digestate is or are introduced on the bottom side and swirling, and also directly into the bottom side

Turbulence of the introduced slurry or digestate

A precipitant is injected continuously with, so that the mixture of manure or digestate together with the injected precipitant in the precipitation container is ascending and expanding upwards so that it flows out of the top of the precipitation vessel and is introduced into the settling container.

2. The method according to claim 1,

characterized,

that the precipitation container has a cylindrical upright shape, which is filled from bottom to top.

3. The method according to claim 1 or 2,

characterized,

that in the vortex of the bottom of the

Discharge tanks introduced manure or

Fermentation residues in the same direction of turbulence with acidified water is introduced.

4. The method according to claim 2 or 3,

characterized,

that the acidified water at the anode of a

Electrolysis reaction of salts in water withdrawn water, which is called anolyte. Method according to claim 2 or 3,

characterized,

the acidified water is produced by addition of acetic acid, or propionic acid, or sulphurous acid, or citric acid or lactic acid.

Method according to one of the preceding claims

1 to 4, characterized

that in the settling tank before the passage of the mixture of manure or digestate along with the injected

Precipitant and optionally the acidified water, a lot of water is submitted, and said from the

Precipitated vessel passed over mixture is passed from the top of the water introduced, for the separation of thick or flake phase of the thin or clear phase.

Method according to one of the preceding claims

1 to 4,

characterized,

that the precipitation container is an upright cylindrical container, and that the said turbulence is generated by a placed for the cylindrical longitudinal axis eccentric placed introduction for manure / digestate.

Method according to one of the preceding claims

1 to 4,

characterized,

that said turbulence is generated by a rotating element.

Method according to one of the preceding claims

1 to 6,

characterized,

that in the settling tank forming

floating floc or thick phase through

Skimming or pushing off is deducted, and the

remaining thin or clear phase through the

Addition of lime or dilute potassium hydroxide further clarified and used as nutrient for plant cultures

is deducted. Method according to one of claims 1 to 9,

characterized,

that the precipitant optionally at different

Inj ektionsstellen of the precipitation container is or can be initiated, which on different

Altitudes, measured from the bottom of the precipitation tank

are arranged, such that so that the

Effectiveness of precipitation to different

Rotational speeds and / or viscosities

customizable to different precipitating gullies

is. Method according to one of claims 1 to 10,

characterized ,

that also another optional introduction opening of

Manure and / or water and / or anolyte and / or

Katholyt is provided in the bottom of the precipitation container, about which without rotation of one of the mentioned

Media can be introduced. Device for carrying out the method according to

one of claims 1 to 11, for the treatment of

agricultural manure and digestate, in which the manure or digestate added a precipitant, and

then with water as a separating agent in one

Absetzbehältnis a thick or flake phase is separated from a clear or thin phase, characterized in that

in that the settling tank (10) has a precipitation tank (1)

is upstream, which is to fill from bottom to top, in which the manure or digestate on the bottom side over a

Einleitflansch (5) vortexing is introduced, and also on the bottom side directly into the said turbulence of the introduced manure or digestate a precipitant steadily over a

Injection flange (6) is injected, such that the mixture of liquid manure or fermentation residues together with the inj

Precipitant in the precipitating tank (1) ascending and expanding upward, so that it flows out of the top of the precipitation container from a discharge opening (4) and into the settling container (1) can be introduced.

13. Device according to claim 12,

characterized in that

in that the precipitation container opens towards the discharge opening (4) with a conical and funnel-shaped flow cross-section

tapered pipe section (3) is provided, and that the

Outlet opening (4) itself is provided with a pipe connection flange.

14. Device according to claim 12 or 13,

characterized,

the precipitation container (1) is an upright cylindrical container to be filled from the bottom to the top, and that said turbulence can be generated by a liquid / digestate introduction opening (5) placed eccentrically to the vertical axis and placed on the bottom side.

15. Device according to one of claims 12 to 14,

characterized,

that also eccentric to the said vertical

Cylinder axis on the bottom side another opening (6) for

Initiation of precipitant is arranged.

16. Device according to one of claims 12 to 15,

characterized,

that also eccentric to said

vertical cylinder axis on the bottom side another opening (7) for the introduction of acidified water or acid is arranged.

17. Device according to claim 12,

characterized,

that to create a vortex at the bottom of the

Precipitation vessel mechanically rotating means

are provided.

18. Device according to one of claims 12 to 17,

characterized,

that the transition region from the output of the

Precipitation container (19) in the settling tank (10) takes place through a transfer pipe, in which further injection openings are provided as flange connections through which precipitation and / or

Separating agent and / or surfactants are injectable before the transferred manure or digestate stream reaches the settling tank.

19. Use of a precipitation container according to

Claims 12 to 17,

characterized,

that in the operation of manure operated

Biogas plants of said precipitation tanks (1)

is used to slurry in this way or

Pre-treat Gärbreiströme prior to introduction into a respective fermenter of said biogas plants, and then makes a controlled feeding of the fermenter with the resulting flake phase from the manure.

20.Use of a precipitation container according to claims 12 to 17,

characterized ,

that the said precipitation container (1) in the filling of digestate or slurry storage in the stream before reaching the Gärreste- or slurry storage

Hydrogen sulfide (H ₂ S) bond.