2016 ASHRAE Annual Conference

In this presentation, valuable information about demand control ventilation (DCV) in laboratory animal facilities will be shown as stated below. 1) Practical approach and method of DCV by indoor air quality (IAQ) sensing, 2) Actual trend graphs of IAQ sensing and ventilation rates which are synchronized with animal biorhythm (circadian rhythm) and 3) Successful results of saving HVAC energy by reducing total ventilation.

 In a major Japanese laboratory animal facility, a multiplexed IAQ sensing system which continually measures certain types of IAQ values at multiple locations was installed, and VAV control which varies ventilation rates based on those IAQ measurements was implemented. Because it was a first trial of automated DCV in Japan, target areas were confined to two (one rodents’ and one primates’) animal holding rooms, and a step-by-step approach was taken as follows. 1) In order to find out the correlation between ventilation rates and IAQ values, ventilation rates was changed manually (6, 9, 12, 15 ACH for every 2 weeks) with continuing multiplexed IAQ sensing. 2) Based on the results of the foregoing analysis, automated DCV in accordance with concentration differences between supply and room (or room exhaust) air was implemented. The DCV was tried under the conditions of three series of set points (“low”, “middle” and “high”). In the case of “low” set points, ACH varied synchronized with animal biorhythm (circadian rhythm) and total ventilation was saved by 20.6-27.5%. On the other hand, in the case of “high” set points, ACH almost did NOT increase except during the in-room activity (e.g., cage changing or room cleaning) and total ventilation was saved by 47.5-48.7%

The safe and effective operation of a science facility deep underground poses a number of ventilation and cooling challenges. Ventilation air must be delivered from the surface to the occupied space and conditioned to meet the space requirements. Exhaust air and heat generated by the facility and its supporting infrastructure must be removed from the underground spaces and rejected back to the surface. The mechanical design must overcome these challenges while limiting its footprint given the high cost of underground excavation.

This paper will present the details of the mechanical ventilation and cooling design for a science facility located 4,850 ft underground in a former gold mine. The site will be comprised of 3 large caverns and a network of tunnels to be excavated over 6 phases. The installation of airside and waterside equipment will take place as the excavation proceeds posing operational challenges in meeting the space requirements. Mine ventilation air will be cooled and supplied to the experiment caverns through water cooled air handling units picking up heat from the spaces. Exhaust fans remove air from the space meeting the air change requirement and deliver the air to an underground spray chamber. The spray chamber is an excavated space where condenser water from the chiller is sprayed into the exhaust airstream. The exhaust airstream picks up heat from the sprayed water and returns to the surface through a vertical borehole while cooled condenser water returns to the chillers.

The paper also presents the constructability considerations which are a result of the phased excavation and operation of the facility. The mechanical design is flexible to limit the incremental changes between phases while maximizing the use of the excavated space and minimizing the client’s costs.

Energy efficiency in the industrial processes  has great potential to reduce the energy demand, as well as green house gases emission, which is the most concerned topic in the gobal warming debate. In fact, the improvement of energy efficiency and an intelligent linkage of the energy consumer, distribution, storage, and energy supply are the keys to lower the energy consumption in the industry. In this paper, the research is focused on the study of these combinations in the industry via a plastic factory case study at different climate conditions. The plastic processing industry uses mainly electric power for their machines and facilities. Especially, plastic products for the food and pharmaceutical sector requires significant demands on air temperature and humidity control. This leads to high energy requirements on the power supply system. In order to obtain flexibitlity in using machines from many different energy sources such as CHP processes, the burning of gas, or electrical grid, the electrical heating method is changed to thermal oil heating in many production machines. The reconstruction of many molding machines, building techonolgy, and the thermal grids in the plastic factory enhances the use of heat generated by a CHP unit. In addition, by changing the refrigeration supply from a compression to an absorption chiller, the use of the heat is increased even further. From a case study presented, the primary energy demand is lowered by up to 57 percent. The study shows the energy savings potential for a manufacturing company located in three different locations: in Germany, Canada and the USA.