Composition and method for continuous or intermittent removal of soil from recirculated washing solution

Patent metadata

Field	Value
Publication number	US-10287192-B2
Application number	US-201213422558-A
Country	US
Kind code	B2
Filing date	Mar 16, 2012
Priority date	Mar 17, 2011
Publication date	May 14, 2019
Grant date	May 14, 2019

Abstract

A method of removing food soils from a recirculated washing solution includes adding a flocculating agent to the recirculated washing solution and separating the particulates from the recirculated washing solution using a hydrocyclone. The flocculating agent causes a portion of the food soils to combine into particulates having a higher density.

First claim

The following is claimed:

1. A method of removing food soil particles from a recirculated wash solution comprising:
adding a detergent composition into a dishmachine to prepare a wash solution having a pH between about 7 and about 13, the detergent composition comprising a cationic flocculant;
performing a wash cycle using a wash solution to form a used wash solution;
collecting the used wash solution, the used wash solution comprising a food soil level of about 2,000 ppm or higher wherein the food soil comprises food soil particles of less than 2 mm in size and the cationic flocculant causes agglomeration of the food soil particles into agglomerated particles greater than 2 mm in size and having a density greater than water;
recirculating the used wash solution;
separating the agglomerated particles from the recirculating used wash solution using a mechanical separation device resulting in a permeate stream; and
reusing the permeate stream in at least one wash step.

2. The method of claim 1 , wherein the mechanical separation device is used during at least a portion of the wash cycle.

3. The method of claim 1 , wherein the mechanical separation device is used continuously during the wash cycle.

4. The method of claim 1 , further comprising returning the permeate stream to the sump prior to reusing the permeate stream.

5. The method of claim 1 , wherein the mechanical separation device is a hydrocyclone.

6. The method of claim 5 , wherein the flocculant increases the efficiency of the hydrocyclone by about 90%.

7. The method of claim 1 , wherein the used wash solution has a food soil level of 6,000 ppm or higher.

8. The method of claim 1 , wherein the used wash solution has a food soil level of 10,000 ppm or higher.

9. The method of claim 1 , wherein the food soil particles are less than 1 mm in size.

10. A method of removing food soils from a dishwash solution comprising:
adding a detergent composition into a dishmachine to prepare a dishwash solution having a pH between about 9 and about 12, the detergent composition comprising a cationic flocculant;
performing a first wash cycle using the dishwash solution;
collecting the used dishwash solution, the used dishwash solution having a food soil level of about 2,000 ppm or higher wherein the food soil has particles of less than 2 mm in size,
wherein the flocculant causes formation of agglomerated food soil particles having a density greater than at least one individual food soil particle prior to agglomeration;
separating the agglomerated food soil particles from the dishwash solution using a mechanical separation device into a concentrate stream, wherein the agglomerated food soil particles are separated based on the density of the agglomerated food soil particles;
separating the remaining dishwash solution into a permeate stream; and
recycling the permeate stream into a second wash cycle in the dishmachine.

11. The method of claim 10 , wherein the mechanical separation device is a hydrocyclone.

12. The method of claim 11 , wherein the flocculant increases the efficiency of the hydrocyclone by about 90%.

13. The method of claim 10 , wherein the dishwash solution comprises about 0.1 ppm to about 100 ppm of the cationic flocculant.

14. A method of removing food soil particles from a recirculated aqueous solution comprising:
adding a detergent composition into a dishmachine to prepare a wash solution having a pH of between about 7 and about 13, the detergent composition comprising a cationic flocculant;
performing a wash cycle, including at least one wash step using the wash solution and at least one rinse step;
collecting an aqueous solution, the aqueous solution comprising at least a portion of the wash solution and 5,000 ppm or higher food soil particles having a size of less than 1 mm, wherein the cationic flocculant causes agglomeration of the food soil particles into agglomerated particles;
separating the agglomerated particles having a density greater than that of water from the aqueous solution; and
reusing the wash stream in at least one wash step.

Assignees

• Besse Michael E
• Tjelta Brenda L
• Osterberg Daniel M
• Ecolab Usa Inc

Inventors

• Besse Michael E
• Tjelta Brenda L
• Osterberg Daniel M

Classifications

• A47L15/0055

  Metering or indication of used products, e.g. type or quantity of detergent, rinse aid or salt; for measuring or controlling the product concentration · CPC title

• C11D3/10

  Carbonates {; Bicarbonates} · CPC title

• C02F1/52 Primary

  by flocculation or precipitation of suspended impurities {(C02F1/463 takes precedence)} · CPC title

• C11D3/3769

  (Co)polymerised monomers containing nitrogen, e.g. carbonamides, nitriles or amines · CPC title

• A47L15/4202

  Water filter means or strainers · CPC title