Refinery-wide Maintenance Vent Compliance Program Development Strategies Presented by Phil Fish, Barr Engineering Co. – pfish@barr.com April 2018
• Miscellaneous Process Vent (MPV) and Maintenance Vent (MV) Overview Presentation Group 1 MPV vs. Group 2 MPV vs. MV − • Three phases of refinery-wide MV compliance Overview program development ▪ Steering ▪ Mobilizing ▪ Implementing • Two equipment screening approaches for sorting equipment into smaller groups Reference-Volume approach − Three-Groups approach − • Program documentation considerations • Ongoing program improvement strategies
• MPVs are broadly defined as gas streams discharged from a process unit MV Regulatory • Dec. 2015 rule adds work practice Background standards (WPS) resulting from removal of the Startup, Shutdown, Malfunction (SSM) exemption • Compliance date of August 1, 2017, or 2018 if extension has been granted • Prior to compliance date, comply with general duty to minimize emissions for each maintenance activity • EPA technical rule amendments signed on March 19, 2018
Group 1 Group 2 MPV MPV MPV Group >72 lb VOC/day emissions <72 lb VOC/day emissions Designations Route to flare, heater or CE One-time notification “For vents only used as a result of startup, shutdown, maintenance, or inspection of equipment where equipment is emptied, depressurized, degassed or placed into service” MV >72 MV <72 >72 lb VOC inventory <72 lb VOC inventory Measure LEL (or <5 psi) Document calculations MV Blinding <2 psi (proposed) Document justification
• Three basic steps: 1. Determine Individual MV applicability Compliance (before event) Flow Chart 2. Control and monitor emissions for compliance (during event) 3. Complete required recordkeeping and reporting
I Steering Phased • What are the interpretations, assumptions and risks with different compliance approaches? Compliance • Who is responsible for certain tasks? Strategy II Mobilizing • How will each piece of equipment comply? • How do we estimate VOC emissions or the mass contained? III Implementing • How do we manage compliance on a day-to-day basis for individual equipment maintenance? • How do we manage compliance for large unit TARs?
• Goal: Determine key interpretations, assumptions and risks for compliance. Steering Phase • Non-linear – may need to revisit initial (1/2) decisions based on new/additional information − EPA rule changes or clarifications − Field measurements − Chemical cleaning vendor guarantees • On-board key refinery stakeholders − Operations, Maintenance, Engineering, Turnaround Planner, Environmental, Safety
• Evaluate current venting practices Can the refinery meet the WPS today? − Steering Phase What are the current procedures when equipment is − >10% LEL? (2/2) How is equipment vented during planned TAR? − What pyrophoric equipment is connected to a pure − hydrogen supply? • Align on key regulatory interpretations G2 MPV vs. MV − Review EPA’s April 2017 responses to AFPM/API July − 2016 request for clarifications. • Evaluate practice changes or strategies Additional purge cycles − Longer chemical cleaning − Capital projects to better prepare equipment for venting −
• Goal: Collect additional information and assimilate into spreadsheet(s) to Mobilizing determine how to comply for each vent. Phase • Follow the key Steering Team decisions (1/2) and interpretations. • Smaller team − Engineering, Environmental, Turnaround Planner • Evaluate available process stream data sets − HYSYS/ASPEN modeling, storage tank representations, etc.
• Gather inventory of vents (equipment and piping sections) Mobilizing • Develop calculation templates Phase − Calculate VOC mass in gas and residual liquid (2/2) from equipment and associated piping • Utilize assumptions to screen equipment into smaller groups • Gather empirical data to inform steering decisions
Empirical Data Method 21 screening • Mobilizing Method 18 bag sampling • Field-measured T&P • Phase - Calculation Refinements Refinement Steam / nitrogen purging • Hierarchy Realistic T&P • Equipment measurements • Worst-case Saturated temperature • Increasing Increasing Increasing Maximum pressure per Safety • effort sensitivity accuracy Process stream speciation to changes •
• Screen equipment into smaller groups Reference-Volume approach − Mobilizing Three-Groups approach − • Searching for low-hanging fruit Phase - • Exclude small equipment unable to contain 72 lb Equipment- VOC of vapor Based Worst-case assumptions − Doesn’t account for clingage or liquid heel Screening − • “Rule of thumb” -type exercise Can the equipment contain >X% of 72 lb VOC with − worst-case assumptions? Safety factor to account for uncertainty (clingage) − • Utilize process engineer’s knowledge/experience to reduce calculation burden and improve accuracy
Compliance Demonstration Strategy >72 lb VOC Reference- Towers • Volume (RV) Reactors • Drums WPS (LEL or, if • Screening Small drums w/ piping • cannot measure Large HX w/ piping • Approach LEL, <5 psi) Long piping runs • 72 lb RV (X ft 3 ) <72 lb VOC HX MV Calculation • Pumps • Documentation Filters • (or possibly treat as G2 MPV) VOC Volume
Compliance Demonstration >72 lb VOC Strategy WPS (LEL or, if Three-Groups Towers • cannot measure Reactors • Screening LEL, <5 psi) Drums • Approach Approx 72 lb VOC WPS or 72 lb V 72 Small drums w/ piping • MV Calculation (X ft 3 ) Large HX w/ piping • Documentation Long piping runs • <72 lb VOC MV Calculation Documentation HX • (or possibly Pumps • designate as Filters • G2 MPV) VOC Volume
RV or V 72 Equipment Analysis List RV or V 72 Process Unit Process Engineer Engineer Questionnaire Questionnaire Workflow Equipment Equipment Equipment <<RV or V 72 ~V 72 ±X% >>RV or V 72 Done – Refine Refine MV Calculation or WPS Documentation or WPS Three-Groups Approach Only
• Goal: Determine “boots on the ground” compliance approach. Implementing • Full stakeholder team Phase − Operations, Maintenance, Engineering, Turnaround Planner, Environmental, Safety • Incorporate WPS into day-to-day operations − Safe Work Permits − Separate MV documents or inventories listing equipment subject to WPS • Establishing procedures for evaluating venting during upcoming turnarounds • Develop recordkeeping procedures
• Consolidating MV determinations, calculations and documentation into a MV single plan Compliance • Plan main text includes: Plan − Rule definitions Document − Steering team decisions and interpretations • Appendices include: − Unit-specific discussion, calculations and process engineer questionnaires − Example recordkeeping forms − Refinery-wide background documentation ▪ RV/V 72 calculations
• The goal is to reduce compliance burden or improve accuracy Program • Additional sampling or recordkeeping Improvement − Method 21 screening (concentration) or Strategies Method 18 bag sampling (speciation) equipment to validate calculations − Recording T&P data for routine maintenance activities to refine calculations • Revising SOPs to improve calculation parameters − E.g., do not vent if system pressure is >3 psig. • Updating MOC procedures to evaluate changes to MV applicability
Thank you Contact information: Phil Fish Barr Engineering Co. (952) 842-3643 pfish@barr.com
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