Vacuum grinding system and method

A continuous vacuum grinding method for a vacuum grinding system comprising a plurality of elements connected in series, said elements comprising:

• an inlet chamber adjacent to an inlet of the system, the inlet chamber being provided with an inlet material flow control valve arranged, when opened, to accommodate a material to be ground in the inlet chamber, the inlet chamber being configured to be connected in fluid connection to a vacuum pump;
• a grinding chamber comprising a grinder, arranged downstream of the inlet chamber and provided with a grinding flow control valve configured, when opened, to allow the material to be ground to be transferred from the inlet chamber to the grinding chamber, the grinding chamber being connected in fluid connection to the vacuum pump;
• and an outlet chamber, downstream of the grinding chamber and adjacent to an outlet of the system, the outlet chamber being provided with a post-grinding flow control valve configured, when opened, to allow ground material to pass from the grinding chamber into the outlet chamber, the outlet chamber being in fluid connection to the vacuum pump;
• the system being configured to control-opening and closing of the inlet material flow control valve and of the grinding flow control valve to maintain the grinding chamber under vacuum at an oxygen concentration equal to or less than 10% in the absence of inert gas while the material to be ground is transmitted from the inlet chamber to the grinding chamber before the material to be ground previously introduced into the grinding chamber has been completely ground, wherein the inlet chamber and the grinding chamber are maintained under vacuum by the vacuum pump, wherein an outlet level-sensor is included between the inlet chamber and the outlet chamber, the outlet level-sensor comprising a sensor at an outlet of the grinding chamber and a sensor at an inlet of the outlet chamber before the post-grinding flow control valve;
• and wherein a signal from the outlet level-sensor controls the opening and closing of the post-grinding flow control valve such as to generate an outlet accumulation zone of the ground material between the grinder and the post-grinding flow control valve;
• the method comprising the steps of, in this order:
• opening the inlet material flow control valve and admitting the material to be ground into the inlet chamber;
• after admission of the material to be ground into the inlet chamber, closing the inlet material flow control valve and evacuating the inlet chamber;
• opening the grinding flow control valve for establishing a fluid connection between the inlet chamber and the grinding chamber to supply the grinding chamber with the material to be ground;
• after admission of the material to be ground into the grinding chamber, interrupting the fluid connection between the inlet chamber and the grinding chamber by closing the grinding flow control valve;
• grinding the material using the grinder;
• opening the post-grinding flow control valve for establishing a fluid connection between the grinding chamber and the outlet chamber to ensure that the ground material passes into the outlet chamber;
• interrupting the fluid connection between the grinding chamber and the outlet chamber by closing the post-grinding flow control valve;
• reducing or stopping an air-evacuation of the outlet chamber until a pressure of the outlet chamber reaches a predetermined output threshold;
• carrying out the passage of the ground material from the outlet chamber to the outlet of the vacuum grinding system by opening an outlet flow valve;
• and
• controlling the opening and closing of the inlet material flow control valve and of the grinding flow control valve to maintain the grinding chamber under vacuum at the oxygen concentration equal to or less than 10% in the absence of inert gas while the material to be ground is transmitted from the inlet chamber to the grinding chamber before the material to be ground previously introduced into the grinding chamber has been completely ground, wherein the inlet chamber and the grinding chamber are maintained under vacuum by the vacuum pump.

A continuous vacuum grinding system having a plurality of elements connected in series, said elements comprising:

• an inlet chamber adjacent to an inlet of the system, the inlet chamber being provided with an inlet material flow control valve arranged, when opened, to accommodate the material to be ground in the inlet chamber, the inlet chamber being configured to be connected in fluid connection to a vacuum pump;
• a grinding chamber comprising a grinder, arranged downstream of the inlet chamber and provided with a grinding flow control valve configured, when opened, to allow the material to be ground to be transferred from the inlet chamber to the grinding chamber, the grinding chamber being connected in fluid connection to the vacuum pump;
• and
• an outlet chamber, downstream of the grinding chamber and adjacent to an outlet of the system, the outlet chamber being provided with a post-grinding flow control valve configured, when opened, to allow the ground material to pass from the grinding chamber into the outlet chamber, the outlet chamber being in fluid connection to the vacuum pump, the outlet chamber further comprising an outlet flow valve configured, when opened, to output the ground material;
• the system being configured to control-opening and closing of the inlet material flow control valve, the grinding flow control valve, the post-grinding flow control valve and the outlet flow valve to maintain the grinding chamber under vacuum at an oxygen concentration equal to or less than 10% in the absence of inert gas while the material to be ground is transmitted from the inlet chamber to the grinding chamber before the material to be ground previously introduced into the grinding chamber has been completely ground, wherein the inlet chamber and the grinding chamber are maintained under vacuum by the vacuum pump;
• the system further comprising a first flow regulator for controlling a quantity of material to be ground, the first flow regulator being between the grinding flow control valve and the grinding chamber;
• and
• a second flow regulator for controlling an amount of ground material exiting the outlet chamber, the second flow regulator being downstream of the outlet flow valve
• wherein an outlet level-sensor is included between the inlet chamber and the outlet chamber, the outlet level-sensor comprising a sensor at an outlet of the grinding chamber and a sensor at an inlet of the outlet chamber before the post-grinding flow control valve;
• and
• wherein a signal from the outlet level-sensor controls the opening and closing of the post-grinding flow control valve such as to generate an outlet accumulation zone of the ground material between the grinder and the post-grinding flow control valve.

A continuous vacuum grinding system having a plurality of elements connected in series, said elements comprising:

• an inlet chamber adjacent to an inlet of the system, the inlet chamber being provided with an inlet material flow control valve arranged, when opened, to accommodate the material to be ground in the inlet chamber, the inlet chamber being configured to be connected in fluid connection to a vacuum pump;
• a grinding chamber comprising a grinder, arranged downstream of the inlet chamber and provided with a grinding flow control valve configured, when opened, to allow the material to be ground to be transferred from the inlet chamber to the grinding chamber, the grinding chamber being connected in fluid connection to the vacuum pump;
• and
• an outlet chamber, downstream of the grinding chamber and adjacent to an outlet of the system, the outlet chamber being provided with a post-grinding flow control valve configured, when opened, to allow the ground material to pass from the grinding chamber into the outlet chamber, the outlet chamber being in fluid connection to the vacuum pump, the outlet chamber further comprising an outlet flow valve configured, when opened, to output the ground material;
• the system being configured to control-opening and closing of the inlet material flow control valve, the grinding flow control valve, the post-grinding flow control valve and the outlet flow valve to maintain the grinding chamber under vacuum at an oxygen concentration equal to or less than 10% in the absence of inert gas while the material to be ground is transmitted from the inlet chamber to the grinding chamber before the material to be ground previously introduced into the grinding chamber has been completely ground, wherein the inlet chamber and the grinding chamber are maintained under vacuum by the vacuum pump;
• the system further comprising a first flow regulator for controlling a quantity of material to be ground and an inlet level-sensor provided between the inlet chamber and the first flow regulator;
• and
• an outlet level-sensor provided between the inlet chamber and the outlet chamber, the outlet level-sensor comprising a sensor at an outlet of the grinding chamber and a sensor at an inlet of the outlet chamber before the post-grinding flow control valve;
• and
• wherein a signal from the outlet level-sensor controls the opening and closing of the post-grinding flow control valve such as to generate an outlet accumulation zone of the ground material between the grinder and the post-grinding flow control valve.