Method and Device for Controlling the Production of an Extract Using a Solid-Liquid Extraction Process

A device for controlling the production of an extract by means of solid-liquid extraction using an extraction container, wherein:

• the extraction container has at least one first inner region that, in a top region, possesses a first supply connection for supplying a primary mixture, and, in a bottom region, a drainage connection for drainage of a mixture consisting of an extract and a raffinate,
• in a top region, the extraction container possesses a second supply connection for supplying a secondary solvent,
• the drainage connection discharges into a drain line,
• the drain line has, viewed in a direction of flow and at a vertical distance from the drainage connection by a supply height relative to the direction of gravity, a control valve, a first mass flow meter for determining a first mass flow {dot over (m)}1 for the mixture, a separating device for separating the mixture into the extract and a raffinate with residual moisture, a dehumidification apparatus for dehumidifying the raffinate with residual moisture, and a second mass flow meter for determining a second mass flow {dot over (m)}2 for an extract free from raffinate with residual moisture,
• the separating device and the dehumidification apparatus are realized in the form of a controllable vibration or shaking sieve, and
• a control apparatus is provided that, in terms of signaling, is at least connected to the control valve, the first and the second mass flow meters, and the vibration or shaking sieve, and that controls the degree of dehumidification by a feedback control intervention in the first mass flow and the supply of mechanical energy.

A device for producing an extract by means of solid-liquid extraction by means of a third extraction container from which a circulation line branching off a drain line runs, wherein:

• the third extraction container:
• has a supply line for supplying a secondary solvent or a mixture consisting of a primary mixture and the secondary solvent, and the supply line enters via a third foot area into the third extraction container, penetrates the third extraction container up to a third headspace, and discharges at the third headspace via an outlet, and
• has a drainage connection for discharging the secondary solvent or a mixture consisting of an extract and a raffinate, and the drainage connection leaves the third foot area and transitions there into the drain line,
• the drain line has, viewed in a direction of flow and at a vertical distance from the drainage connection by a supply height in the direction of gravity:
• a control valve, a first mass flow meter for determining a first mass flow {dot over (m)}1 for the mixture, a separating device for separating the mixture into the extract and a raffinate with residual moisture, a dehumidification apparatus for dehumidifying the raffinate with residual moisture, and a second mass flow meter for determining a second mass flow {dot over (m)}2 for an extract free from raffinate with residual moisture, wherein the separating device and the dehumidification apparatus are realized in the form of a controllable vibration or shaking sieve,
• from the drain line, upstream from the control valve:
• the circulating line branches at a branching point and joins the supply line at a joining point, and is flowed through from the branching point to the joining point, and
• inside the circulating line, relative to the branching point, first a pump for conveying the secondary solvent and then a dosing apparatus for dosing primary mixture into the secondary solvent are provided, and
• a control apparatus is provided that, in terms of signaling, is at least connected to the control valve, the first and the second mass flow meters, and the vibration or shaking sieve, and that controls the degree of dehumidification by a feedback control intervention in the first mass flow and the supply of mechanical energy.