Development of Innovative Ventilation Systems for Fattening Pigs : Part I - Method and First Results

Abstract

The aim of the above named project at the Institute of Agricultural Engi- neering (University Hohenheim) is to develop and to test several innova- tive ventilation systems. The investigations focus on an improved indoor air quality, the reduction of environmentally toxic and greenhouse gases from animal husbandry and the technical use of additional housing and animal parameters to control the indoor air climate within the scope of Precision Livestock Farming. To reach this aim experimental work is done for more than one year in the Hohenheim research facility for fat- tening pigs. The experimental pig facility is subdivided in two compart- ments and features two different feeding systems. For the investigations the research facility was upgraded according to current animal welfare requirements. Furthermore the climate control was equipped with a high pressure water fogging system for humidifying and cooling the air. Addi- tional control parameters which influence the degree and the reaction of the ventilation rate in different ways and which starts e.g. the water fog- ging, are the animal activity and the CO 2 -indoor concentration in the compartment. Based on a continuous data collection with high temporal resolution over four fattening periods, data on the indoor air climate and the emission as well as further side effects are recorded within rotating ventilation strategies in the two compartments. In a following step the emissions of NH3 , CO2 and CH 4 are calculated including the background concentration and the exhaust air concentration of each gas, the water vapour cross sensitivity of the gas analysers and the ventilation rate measured simultaneously. Due to the developed innovative experimental design the evaluation of the control strategies encloses different influenc- ing factors like seasonal effects, measuring sections, the feeding systems, the compartments or the effect on the indoor air climate. Part I of the three-part proceedings explicates mainly the developed experimental lay- out, the operating mode of the control strategies, their technical realisa- tion and the approach of the investigation including the data logging sys- tem. Furthermore the practical functionality of the control strategies is described and pictured within the first selected results. The figures com- pare the indoor temperatures, the ventilation rates and the CO2 -indoor concentrations of both compartments, featuring different ventilation con- trol strategies at the same time. The first results indicate the effectiveness of the different ventilation control strategies. When finishing the practi- cal research work in early summer 2004, the final evaluation of the com- pleted data-set is scheduled subsequently.