Ejemplo Hazop

Diammonium Phosphate (DAP) Production Phosphoric acid and ammonia are mixed, and a non-hazardous product, diammonium phosphate (DAP), results if the reaction of ammonia is complete (see Fig. 3). Iftoo little phosphoric acid is added, the reaction is incomplete, and ammonia is produced. Too little ammonia available to the reactor results in a safe but undesirable product. Valve A

PhosphoricAcid study line 1 phosphoric acid delivery line Valve C

Ammonia

Valve B Diammonium Phosphate (DAP)

Reactor

Fig. 3. Continuous process for the production of DAP

ASSESSMENT (HAZID) Bothchemicals will be used in large quantities and in concentrated form. Due to the highly corrosive nature of both chemicals, the project team was assigned to investigate the hazards posed to staff from thereaction resulting from study line 1 (phosphoric acid delivery line).

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H AZOP STUDY RECORD SHEET SYSTEM: DAP PRODUCTION PROCESS PARAMETER: FLOW (Primary keyword) LINE: STUDY LINE 1 NO. 1GUIDE WORD NO DEVIATION NO FLOW

PROJECT: AMMONIA PLANT PRESENT: HAZOP TEAM MEMBER LIST CHAIRED: HAZOP LEADER CONSEQUENCES Excess ammonia in reactor and release to work area. • • • SECRETARY: TEAMMEMBER POSSIBLE CAUSES Valve A fails closed. Phosphoric acid supply exhausted. Pipe ruptures Valve a partially closed. • Partial plug or leak in pipe. Team member to calculate toxicity vs flow reduction.Set point determined by toxicity vs flow calculation. Automatic closure of valve to reduce flow from phosphoric acid supply. ACTION REQUIRED Automatic closure of valve B on loss of flow fromphosphoric acid supply.

DATE: DD/MM/YY PAGE: 1 TOTAL PAGES:1 PERSON DONE (sign off)

2

LESS

LESS FLOW

Excess ammonia in reactor and release to work area. With amount released related toquantitative reduction in supply. Team member to calculate toxicity vs flow reduction. Excess phosphoric acid degrades product. No hazard to work area. Excess ammonia in reactor. release to work area, with...