Ammonia emission in cowsheds and pigsties during the summer periood

O. Sada, E. Mikson and B. Reppo

Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56,
EE51014 Tartu, Estonia

Abstract:

As is known, cows in uninsulated cowsheds can tolerate lower temperatures much better than higher temperatures, so we can say that these buildings are well suited for animals, although there are problems with workers and the working environment in uninsulated cowsheds in extreme cases, during very low and high outside temperatures. The goal of this study was to identify the outdoor climate impact on the indoor climate in cowsheds with 420, 500 and 500 cow places during winter and summertime. For that, indoor and outdoor temperature, relative humidity and indoor ammonia content were measured simultaneously. The processed results are well applicable when designing new cattle housing or improving the indoor climate of already existing uninsulated cowsheds. Building of large pigsties with deep litter and without litter which use liquid manure removal systems has become a wide practice nowadays. Indoor climate parameters of the working environment have an impact on the human capacity for work and the productivity of animals. Enlargement of pigsties is accompanied with problems regarding the achievement of the required indoor climate for the working environment. For the purpose of studying the pigsties with different animal-keeping technologies and the simultaneous effect of temperature and relative humidity on the emission ammonia content in the air of a pigsty were measured in summer above a pig-pen at the height of 1.5 meters from the floor and were measured daily. Data logger equipment, relevant sensors and content of ammonia in the air was measured for the study by using Gas Monitor Pac III equipment. Measurement results were statistically processed by using the computer programmes AMR Win Control, Pac III Software3.nn, SAS and MS Excel.

Key words:

air temperature, ammonia contend correlation, ammonium hydrate, Data Logger, deep-litter, liquid manure, pens, pigsty, relative humidity, system, tending activities, tending passages, uninsulated cowshed, working environment

Possibilities of Heat Exchanger Use in Pigsty Ventilation Systems

V. Zagorska¹ and A. Ilsters²

¹ Institute of Mechanics, Latvia University of Agriculture,
Liela iela 2, LV-3000, Jelgava, Latvia; e-mail: vzagorska@gmail.com
² Research Institute of Agricultural Machinery, Agency of Latvia University of Agriculture,
Instituta Street 1, Ulbroka, LV-2130, Riga district, Latvia

Abstract:

There is a considerable increase in energy demand during autumn-winter conditions due to the necessity to keep optimal microclimatic conditions in pigsties. When heat exchangers are used in the ventilation systems on the premises of pigsties, clean and cold air (in the autumn-winter period) gets an amount of heat energy from unclean but warm air. Up to now heat exchangers have not been used widely in Latvia and therefore there is no experience about the use of heat exchangers for microclimatic stability in piggeries. The goal of the investigation is to clear out the possibilities of heat exchanger use at farms in Latvian climatic conditions.

The article deals with experimental results obtained from experiments about plate counter-flow heat exchanger models with plastic cellular boards (HE PVC) and plastic plates (WVT 120K) as heat transfer surfaces. Operational parameters which describe the energy efficiency of heat exchangers were calculated – power of recovered heat energy , heat transfer coefficient, and coefficient of performance (COP) by recovered heat. The parameters were analyzed depending on outside air temperature in an interval from +6 C to -16 C.

In the weather conditions of Latvia it is important to achieve heat transfer as completely as possible, widening thus the interval of heat deficit coverage towards lower outside air temperature.

Key words: