WASHING APPARATUS INCLUDING MEANS FOR REMOVAL OF PHOSPHATES FROM THE WASHING SOLUTION

• US 3,772,901 A
• Filed: 06/11/1971
• Issued: 11/20/1973
• Est. Priority Date: 06/11/1971
• Status: Expired due to Term

• Current Assignee: Joseph George Ferraro
• Original Assignee: Joseph George Ferraro
• Inventors: Ferraro, Joseph George
• Primary Examiner(s): Wilhite, Billy J.
• Assistant Examiner(s): Coe, Philip R.
• Application Number:
  US05/152,312
• Time in Patent Office: 893 Days
• Field of Search: 68/208,18F 134/93,100 210/52,199,206 8/158
• US Class Current: 68/18.00F
• CPC Class Codes: D06F 39/02 Devices for adding soap or other washing agents
• CPC Class Codes: D06F 39/10 Filtering arrangements

Abstract

A washing machine or dishwasher includes means for admixing with waste wash water a suitable chemical compound to convert the soluble phosphate in the wash water to insoluble form before discharge of the waste solution to a sewer, drain or other means of disposal. Among the useful chemical compounds employed are calcium chloride, calcium hydroxide and aluminum sulfate, which convert soluble phosphates, including tripolyphosphate and pyrophosphate salts, to insoluble materials, which may be removed from the effluent. Also within the invention are accessories for use with conventional washing apparatuses for effecting the insolubilization reaction, and corresponding processes.

Claims

2. A washing apparatus according to claim 1, which includes a home washing machine, wherein the washing liquid is an aqueous solution comprising a phosphate salt and the chemical compound that reacts with the soluble phosphate is one which produces an insoluble phosphate-containing compound before discharge of the removed solution to the sewer, drain or other means of disposal.

3. A washing apparatus according to claim 2 which comprises a discharge pump, a discharge line and means to contact waste wash water with reactive chemical compound to convert the soluble phosphate therein to insoluble form.

4. A washing apparatus according to claim 3 wherein the means for adding reactive chemical adds it to the discharge line, is adjacent to the other components of the apparatus and is such that the reactive chemical compound contacts the discharged washing solution in the discharge line during the discharge thereof in stoichiometric proportion or excess during substantially all of the time period in which the discharge of the washing solution is effected after washing.

5. A washing apparatus according to claim 4 wherein the reactive chemical compound is calcium hydroxide which is added to the discharged washing solution in the discharge line as a liquid, the means for contacting the wash water with the reactive chemical compound include a container for the liquid, a Venturi restriction, having a throat section, in the discharge passage and means communicating the liquid in the container with the throat of the Venturi so as to feed the reactive chemical liquid to the Venturi when wash water is flowing through it.

6. A washing apparatus according to claim 4 wherein downstream of the point of contact or addition of the reactive chemical compound there is present a holding means to retain the washing solution and reactive chemical compound for a period of time long enough to produce a precipitate of insoluble phosphate-containing compound in cake, coating or layer form or of particle size large enough to be filterable.

7. A washing apparatus according to claim 6 wherein the holding means is a tank built into the structure of a home washing apparatus, which tank is large enough to hold all the washing solution and from which said solution is discharged, after chemical reaction, by displacement with rinse water.

8. A washing apparatus according to claim 3 Wherein the means for reacting a chemical compound with the soluble phosphate is an accessory which is joinable to the washing apparatus between the discharge pump and a discharge line from which used washing solution is discharged to a sewer, drain or other means of disposal.