×

Process and composition for removing a scale deposit

  • US 8,323,416 B2
  • Filed: 07/28/2009
  • Issued: 12/04/2012
  • Est. Priority Date: 06/30/2008
  • Status: Expired due to Fees
First Claim
Patent Images

1. A process for removing one or more scale deposits formed on a surface, comprising the steps of:

  • providing a composition having a first pH of less than about 7.5 to prevent polythionic acid stress corrosion cracking to said surface, said composition comprising;

    a) an effective amount of an organic acid and/or a salt thereof; and

    b) an effective amount of an oxidizing agent selected from the group consisting of a peroxide, a chlorate, a perchlorate, a nitrate, or a permanganate, wherein the organic acid and/or the salt thereof and the oxidizing agent in the composition are in a weight ratio of about 2.5;

    1 to about 1;

    10;

    providing scale deposits comprising primarily metal sulfides and coke formed on said surface, wherein said scale deposits are formed in a hydrocarbon conversion process;

    contacting the surface with said composition for a period of time sufficient to remove one or more scale deposits, wherein during said contacting step, the composition has a second pH, said second pH being greater than the first pH.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×