Heating, Ventilation and Air- Conditioning (HVAC) Supplementary Training Modules on Good Manufacturing Practice
Transcription
Heating, Ventilation and Air- Conditioning (HVAC) Supplementary Training Modules on Good Manufacturing Practice
Supplementary Training Modules on Good Manufacturing Practice Heating, Ventilation and AirConditioning (HVAC) Part 2: HVAC systems and components Section 7 HVAC | Slide 1 of 29 May 2006 HVAC Objectives In the following slides, we will study the components of airhandling systems in order to: HVAC 1. Become familiar with the components 2. Know their functions 3. Become aware of possible problems | Slide 2 of 29 May 2006 HVAC General Design of HVAC is dependent on required degree of air cleanliness Suitable components should be selected including: – – – – fans, driers, filters, ducts, grilles, etc. 7. HVAC | Slide 3 of 29 May 2006 HVAC Main subsystems Exhaust air treatment Fresh air treatment (make-up air) + Terminal air treatment at production room level Production Room Central air handling unit HVAC | Slide 4 of 29 May 2006 HVAC Components Components in HVAC may include, depending on need: Filters Fans – no fan failure; including supply air fans, return air fans, exhaust air fan, dust extract system fans Driers – Drying of air with chemical driers, e.g. rotating desiccant wheel Frost coils for preheating air HVAC | Slide 5 of 29 May 2006 7.1.1 – 7.1.7 HVAC Components Components in HVAC may include, depending on need: Snow eliminators Dust eliminators Moisture eliminators Precooling coils Alarm systems, grilles/diffusers, etc. HVAC | Slide 6 of 29 May 2006 7.1.1 – 7.1.7 HVAC Overview components Exhaust Air Grille Silencer Weather louvre Flow rate controller Fan Control damper + Humidifier Prefilter Cooling coil with droplet separator Secondary Filter Heating coil Recirculated air HVAC | Slide 7 of 29 May 2006 Filter Heater Terminal filter Production Room HVAC Components (1) Weather louvre To prevent insects, leaves, dirt and rain from entering Silencer To reduce noise caused by air circulation Flow rate controller Automated adjustment of volume of air (night and day, pressure control) Control damper Fixed adjustment of volume of air HVAC | Slide 8 of 29 May 2006 HVAC Components (2) Heating unit Cooling unit/ dehumidifier Humidifier Filters Ducts HVAC | Slide 9 of 29 May 2006 To heat the air to the proper temperature To cool the air to the required temperature or to remove moisture from the air To bring the air to the proper humidity, if too low To eliminate particles of predetermined dimensions and/or microorganisms To transport the air HVAC Air-handling unit Control damper for airflow Humid room air Adsorber wheel AHU with fan Variable Speed Controller Regeneration air Humid room air Air heater De-humidification HVAC | Slide 10 of 29 Dry air May 2006 Filter Pressure Gauges HVAC Humidifier HVAC | Slide 11 of 29 Silencer May 2006 Heating and cooling units HVAC Filter classes Dust filters Standard Coarse Fine Dp > 10 µ m 10 µ m > Dp > 1 µ m G1 - G4 F5 - F9 EN 779 Standard HVAC Aerosol | Slide 12 of 29 May 2006 HEPA ULPA Dp < 1 µ m H 11 - 13 U 14- 17 EN 1822 Standard HVAC HEPA or tertiary filter Primary panel filter Secondary filter HVAC | Slide 13 of 29 May 2006 HVAC Classification of filters according to their efficiency HVAC | F9 Average Efficiency Integral Value Retention in Penetration % 85 0.15 H11 95 0.05 H12 99.5 5x10 H13 99.95 5x10 U14 99.995 5x10 Slide 14 of 29 May 2006 Peak Arrestance Local Value Efficiency Penetration -3 97.5 25x10 -3 -4 99.75 25x10 -4 -5 99.975 25x10 -5 HVAC Positioning of filters (1) AHU mounted final filter Filter in terminal position HEPA Filter + Production Room HEPA Filter HVAC | Slide 15 of 29 May 2006 Production Room HVAC Positioning of filters (2) Prefilter AHU Main filter Ceiling exhausts 2 1 Low level exhausts HVAC | Slide 16 of 29 May 2006 3 HVAC Positioning of filters (3) Final filter AHU Prefilter 1 HVAC | Slide 17 of 29 2 May 2006 HVAC 1 2 3 4 Swirl Type air diffusors with terminal filters 1 2 3 4 HVAC Filter Tightening frame Register outlet Screw fixation for register | Slide 18 of 29 May 2006 HVAC High induction office type diffusor (avoid) HVAC | Slide 19 of 29 May 2006 Low induction swirl diffusor (preferred) HVAC Regulation of room pressure – pressure differentials concept Room pressure gauges Room pressure indication panel HVAC | Slide 20 of 29 May 2006 HVAC Problems with components Flow rate controller Control damper Humidifier Cooling battery Filters Ducts HVAC | Slide 21 of 29 May 2006 Blocked Poorly adjusted, bad pressure differential system Bad water/steam quality/ poor drainage No elimination of condensed water/ poor drainage Incorrect retention rate/damaged/badly installed Inappropriate material/internal insulator leaking HVAC In the next slides Consider different air types, e.g.: Supply air Return air (recirculated air) Fresh air (make-up air) Exhaust air And: Concepts of air delivery to production areas: Recirculation systems Full fresh-air systems HVAC | Slide 22 of 29 May 2006 HVAC Air types Fresh air (make-up air) Supply air + Production Room Return air (recirculated) HVAC | Slide 23 of 29 May 2006 Exhaust air HVAC Recirculation systems There should be no risk of contamination and crosscontamination when air is recirculated Normally, HEPA filters (EN1822 H13) needed in supply air stream – Not required in single product facility with no risk of cross-contamination – Not required where no dust generation (e.g. secondary packaging) HEPA filters placed in AHU or terminally Dust from highly toxic processes should not be recirculated 7.2.1 – 7.2.6 HVAC | Slide 24 of 29 May 2006 HVAC Ventilation with recirculated air + make-up air Exhaust Unit Central Air-Handling Unit Return air HVAC | Slide 25 of 29 May 2006 HVAC HVAC | Slide 26 of 29 May 2006 HVAC Full fresh-air systems 100% fresh air - normally where toxic products are processed, and recirculation not recommended No contamination from fresh air – sufficient filtration needed Degree of filtration on exhaust dependent on exhaust air contaminants and environment regulations Energy-recovery wheels – Should not be source of contamination – Relative pressure between supply and exhaust air 7.3.1 – 7.3.3 HVAC | Slide 27 of 29 May 2006 HVAC Ventilation with 100% fresh air (no air recirculation) Washer (optional) Exhaust Unit W Central Air-Handling Unit Production Rooms HVAC | Slide 28 of 29 May 2006 HVAC HVAC | Slide 29 of 29 May 2006