Qatar University (QU) has developed a groundbreaking research initiative to develop a sustainable air conditioning system for poultry houses in hot and humid regions. This project, led by Dr. Djamel Ouahrani, Associate Professor of Architectural Engineering at the College of Engineering at QU, involves a collaboration with Dr. Nesreen Ghaddar and Dr. Kamel Ghali from the American University of Beirut (AUB). The research, funded by the Qatar National Research Fund, aims to address the critical challenges faced by poultry farming in maintaining optimal indoor conditions for bird welfare and productivity.

The global demand for poultry products has surged due to population growth, positioning poultry farming as a preferred method due to its smaller environmental footprint. However, maintaining ideal environmental conditions inside poultry houses is crucial for the welfare of poultry and ensuring high-quality meat production. In hot and humid regions like Qatar, the high indoor temperatures and humidity levels can lead to heat stress in birds, increasing mortality rates and reducing meat production quality and quantity. Additionally, poor air quality, exacerbated by high levels of ammonia (NH3) and carbon dioxide (CO2) produced by chickens, poses a significant risk to bird health.

Commercial poultry houses commonly use conventional ventilation and cooling systems, such as direct evaporative cooling (DEC) systems, to maintain desired conditions. However, DEC systems become less effective in highly humid climates, necessitating the exploration of alternative cooling methods. This research project proposes the Dew-Point Indirect Evaporative Cooler (DPIEC) as an alternative to DEC, which can provide cooling while maintaining constant humidity. Yet, its efficiency decreases in highly humid conditions. To overcome this limitation, a hybrid system combining DPIEC with a desiccant system is projected. This innovative system can reclaim water, enhancing sustainability.

The choice of adsorbent material in the desiccant system is critical. While conventional materials like silica gel have been used, new materials called metal-organic frameworks (MOFs) offer advantages such as higher water uptake and lower regeneration energy. Cost considerations in selecting adsorbent materials (silica gel or MOFs) affect the system's investment and operational costs, including energy consumption. To optimize system performance, mathematical models and artificial neural networks (ANNs) have been employed to develop a sustainable ventilation system for poultry houses in hot and humid regions. Additionally, a Life Cycle Cost (LCC) analysis was conducted to evaluate the economic feasibility of the optimized systems and provide recommendations.

The experimental set-up at the Zero Emissions Lab at QU included key components such as the dehumidification system, evaporative cooling system, and water reclamation unit. The dehumidification system comprises solid adsorbent beads packed in cylindrical beds, operating out of phase to ensure continuous dehumidification. An air-to-air heat exchanger preheats one bed's purge airflow with the hot feed outlet from the other bed. The evaporative cooling system features a cross-flow DPIEC configuration and a water tank for uninterrupted cooling. The water reclamation unit condenses and collects moisture in the air, ensuring efficient water usage.

The system operates based on outdoor air conditions and desired indoor conditions. During the dehumidification stage, outdoor air enters the system, and the required dehumidification level is adjusted based on outdoor humidity. The dehumidified air is mixed with the DPIEC working airstream, and the resulting air mixture undergoes adsorption in the desiccant bed. Heat recovery is achieved by mixing hot and dry air with outdoor purge air. The evaporative cooling stage involves dividing outdoor air into two streams, with the product air cooled in dry channels and supplied to the space, while the working airflow absorbs heat and evaporates water in wet channels. Desiccant regeneration involves heating the pre-heated purge airflow to a regeneration temperature, desorbing water vapor from the desiccant bed, and collecting condensed water.

Operation optimization ensures the system maintains indoor air conditions (temperature, relative humidity, CO2, and NH3 concentrations) while regulating supply air conditions and flow rate. The supply air humidity is controlled by the air humidity at the bed outlet, affecting the DPIEC's operation and supply temperature. The system provides efficient ventilation, cooling, and dehumidification for the poultry house, reclaiming water to reduce reliance on external sources. Key findings include optimal system sizing, ANN training for predicting water vapor adsorption, performance evaluation during the cooling season, and economic analysis comparing silica gel and MIL-101-Cr systems.

The research demonstrates that both silica gel and MIL-101-Cr meet indoor air quality constraints for poultry houses. However, MIL-101-Cr significantly reduces thermal and electrical energy consumption by 17% and 48%, respectively, compared to silica gel. The economic analysis revealed that the MIL-101-Cr-based system has a payback period of 11 years, offering lower running costs.

This innovative approach by QU and the AUB represents a significant advancement in sustainable poultry farming. The collaboration underscores the commitment to developing solutions that enhance animal welfare, reduce environmental impact, and support the knowledge economy in line with Qatar’s Vision 2030.