US 5,308,503 A · Purification of industrial lubricating agents

Abstract

Use of polymeric two-phase systems for removing microbial contaminants from industrial lubricating agents, a method of purifying microbial contaminated lubricating agents by mixing the lubricating agent with a polymeric two-phase system, allowing the mixture to separate so as to form a top-phase containing the lubricating agent and a bottom-phase containing at least part of the microbial contaminants, and separating at least a major part of the microbially enriched bottom-phase from the top-phase, a plant for microbial purification of lubricating agents comprising a mixing tank (4) having means (7, 8) for feeding microbially contaminated lubricating agent (S) to the mixing tank, means (13) for feeding a polymeric two-phase system to the mixing tank, a stirrer (5) in the mixing tank, means (9, 10) for feeding the mixture to a separation device (6) for separating the mixture into a top-phase (T) containing lubricating agents, and a bottom-phase (B) containing microbial contaminants, and means (18) for recovering the top-phase of the two-phase system, and a lubricating agent concentrate, in which at least part of the lubricating agent at the same time forms part of the top-phase component of the polymeric two-phase system.

Claims23

Dependent claims

A method for removing microbial contaminants from a lubricating agent which comprises:

1) mixing the contaminated lubricating agent with an aqueous two-phase system to form a mixture, said system being a composition containing two immiscible aqueous phases, one phase being a top phase containing a hydrophilic polymer dissolved in water and the other phase being a bottom phase, said bottom phase being an aqueous solution containing a component dissolved therein, said component being selected from the group consisting of:
(a) a bottom phase polymer which, when dissolved in water, forms an aqueous solution that is immiscible with the top phase;
said bottom phase polymer having a molecular weight which is higher than the molecular weight of the hydrophilic polymer in the top phase;
and
(b) a water-soluble inorganic salt which, when dissolved in water, forms an aqueous solution that is immiscible with the top phase;
2) allowing the mixture to stratify into said top phase containing the lubricating agent therein and said bottom phase containing at least a portion of the microbial contaminants therein, wherein a microbial enriched bottom phase is formed;
and then
3) separating at least a major portion of the microbially enriched bottom phase from the top phase.

5 more elements

A device for microbial purification of a lubricating agent which comprises:

1) A mixing chamber for mixing top and bottom immiscible liquid phases therein;
said mixing chamber including a first mixing chamber inlet conduit for introducing the top liquid phase therein, and a second mixing chamber inlet conduit for introducing the bottom liquid phase therein;
means for mixing the two phases in the mixing chamber and a mixing chamber outlet conduit for removing the mixed phases from the mixing chamber;
2) a separation chamber for receiving the two mixed phases from the mixing chamber and for allowing said phases to stratify into top and bottom phases within said separation chamber;
said separation chamber being connected to said mixing chamber by said mixing chamber outlet conduit;
3) first and second separation chamber outlet conduits connected to said separation chamber;
said second separation chamber outlet conduit being located below said first separation chamber outlet conduit for removing the bottom phase from said separation chamber;
and said first separation chamber outlet conduit being located above said second separation chamber outlet conduit for removing the top phase from the separation chamber, wherein the first separation chamber outlet conduit is connected to a tank so that the top phase in the separation chamber can flow into said tank;
and said tank includes a first tank outlet conduit connected to said first mixing chamber inlet conduit for the introduction of said to phase into said mixing chamber and said tank further includes a second tank outlet conduit for distributing the top phase to a distribution system and said tank further includes a tank inlet conduit for returning the top phase to the tank from the distribution system, and wherein the second separation chamber outlet conduit is connected to a means for removing microbial contaminants from the bottom phase to produce a purified bottom phase and said device further includes means to return said purified bottom phase to the mixing chamber via said second mixing chamber inlet conduit.

6 more elements

Dependencies are inferred from the claim text.

Purification of industrial lubricating agents

Life of this patent

Purification of industrial lubricating agents

Life of this patent

Abstract

Claims23