Clean zone HVAC system

• US 9,593,859 B2
• Filed: 05/20/2015
• Issued: 03/14/2017
• Est. Priority Date: 04/24/2011
• Status: Active Grant

• Current Assignee: Sarfaraz K. Niazi
• Original Assignee: Sarfaraz K. Niazi
• Inventors: Niazi, Sarfaraz K.
• Primary Examiner(s): LEVKOVICH, NATALIA A
• Application Number:
  US14/717,900
• Publication Number:
  US 20150253022A1
• Time in Patent Office: 664 Days
• Field of Search: 700/277, 700/276, 700/278
• US Class Current: 1/1
• CPC Class Codes: C12M 23/14 Bags
• CPC Class Codes: C12M 25/14 Scaffolds; Matrices in general C12N5/0068
• CPC Class Codes: C12M 27/16 Vibrating; Shaking; Tilting
• CPC Class Codes: C12M 29/06 Nozzles; Sprayers; Spargers; Diffusers per se B01F23/231, B01J19/26
• CPC Class Codes: C12M 41/32 of substances in solution
• CPC Class Codes: C12M 47/10 Separation or concentration of fermentation products bioreactors combined with means for distillation or extraction of liquid fuel C12M43/02
• CPC Class Codes: C12Q 3/00 Condition responsive control processes apparatus therefor C12M1/36; controlling or regulating in general G05
• CPC Class Codes: F24F 7/06 with forced air circulation, e.g. by fan positioning of a ventilator in or against a conduit
• CPC Class Codes: Y10T 137/0318 Processes

Abstract

A single-pass HVAC systems to isolate zones and to maintain a required clean air quality standard is provided that operates by producing a positive pressure in all zones, while exhausting on a minimal quantity of air required by law. The zones are kept clean by a recirculating fan filter in each zone. The exhaust air is used to exchange heat with incoming air to conserve energy further.

Claims

1. A single-pass system for independently controlling the environment in a plurality of building zones comprising:

a central air-handling unit for supplying fresh air comprising;

a heat exchanger including a plenum with a fresh air inlet in fluid communication with outside fresh air;

a fresh air outlet;

the plenum having a radiator with an exhaust air inlet and an exhaust air outlet;

an air handling unit having means of filtering, means of heating, means of cooling, means of humidifying and means of dehumidifying the fresh air, the air-handling unit being in fluid communication with the fresh air outlet of the heat-exchanger;

a plurality of ducts to supply fresh air independently from the air-handling unit to each building zone;

a plurality of exhaust units disposed in each zone and each comprising a fan, a damper and a control mechanism to continuously or periodically exhaust remove a volume of air from each building zone;

a means of extracting thermal energy from the exhaust air comprising a common duct connecting each of the exhaust air units in parallel to the exhaust air inlet of the radiator of the heat-exchanger and allowing the exhaust air to vent.

2. The single-pass system of claim 1, wherein each building zone additionally comprises a secondary air-handling unit capable of filtering, heating, cooling, adjusting humidity and recirculating air independently in each building zone.

3. The single-pass system of claim 1 for independently controlling the environment in a plurality of building zones, wherein the plurality of building zones is a contamination-sensitive zone in pharmaceutical manufacturing, biotechnology manufacturing, surgical rooms healthcare patient facilities, electronic manufacturing operations and a variety of other industries where air particulate count is strictly controlled.