A brief introduction of the HTA positive pressure-negative pressure system and the short term expectations.
Climate control on pig farms has a big impact on health and production. In my view, current ventilation systems are not working properly, which necessitates the search for an optimal system. The big disadvantage of existing systems is the emergence of airflows in the compartments and the lack of optimal usage of fresh air by the pigs. With the new HTA positive-negative -pressure system the fresh air is 100% distributed by the use of positive pressure via a perforated air inlet tube into the animal quarters. By making smart use of the forces naturally generated by the heat production of the animals, fresh air is further distributed into the animal quarters. In all weather conditions the same controlled air movement is generated in a way that 100% of the fresh air is utilised by the pigs. Without a draught!
In a practical trial performed in 2011 it became clear that the system produces a better air distribution than conventional systems. It was not possible to ventilate more than the minimum during this trial with the used air inlet apparatus. Meanwhile we have found the solution that makes it possible to increase this ( in the bandwidth or as the pigs are getting heavier). This has been patented.
To increase in the field experience with the new version of the HTA positive pressure-negative pressure system, it is necessary to take the next step. This involves the installation of this system in a few farms, preferably farms that have to deal with too many lung problems and/or autumn abortions.
Interested farms can contact us by phone (+31) 499-423389. One of the employees of animal clinic Lieshout will answer the phone. Please ask for Wil Jansen
Expectations of the system in the short term:
Due to the more efficient use of the ventilated air, the needed cubic metres volume of ventilation air is less. In many cases the HTA system will contribute in lowering lung diseases and autumn abortions. For long term expectations, please see tabs “System Advantages” and “Waste Reduction”. The beauty in operating the HTA system, is a reduction in operating costs for the pig farmer and an increase in eco-friendly farming and animal welfare.
1986: Internship Veterinary Medicine in Utrecht with Professor Tielen (climate control of pig stables) and Professor Verheijden (pig diseases). During these modules I decided to become actively involved as a practicing veterinarian in the relationship between the climate of a pig barn and lung diseases in pigs. From 1989 until 1994: working on a pig farm with 2,300 sows and 20,000 pigs for the meat market. Part of my work was to do research on the relation between stable climate and lung health of the animals. January 1995 onwards: Applied findings of my previous research to assist and coach other pig farms. January 2008: Commencement of the development of a new air intake system, as I was dissatisfied with the systems used at the time. The new system had to meet three criteria: Not too expensive, applicable in any barn and always resulting in a good stable climate. In 2011 we had the chance to perform a trial at a pig farm. The results from this trial were encouraging, even though we still encountered a few issues that needed to be resolved. We have resolved those issues and there are two patents granted on this system.
Animation of the system
In the animation we use colours to show the four parts of the pig barn’s air. Red shows the movement of warmth. Brown shows the movement of the smelly air, dark blue corresponds with the fresh and clean air and pale blue withthe cold air. The airstreams in most common systems in current use are shown on the left. These existing systems work with a negative pressure, that produces airstreams in your animal quarters. Even after the air has been distributed from the ceilings fairly evenly, this still happens. These airstreams mean inefficient usage of the air, pit ventilation and sometimes drafts. Holland Top Air uses a combination of positive pressure with negative pressure. This is how “flat ventilation” arises. It means that the difference in pressure between air intake and air output in the quarter is little to nothing. How the air travels through the quarter, will become clear in our animation.
Example of a current system
The patented system of Holland Top Air
Explanation of the operating system
The most important differences between the system and conventional systems are as follows.
1. The air is let in through an overhead perforated air intake channel that is hanging above the pigs. Higher pressure exists in this air intake channel. An airstream, that is caused by the heat production of the animals, lifts the fresh air due to the venturi process above the air inlet. There the fresh air is mixed and warmed. This way, ventilation occurs in conjunction with the heat flow of the pigs (upwards) instead of against it (downwards from the ceiling). Energy use is lower.
2. Due to the use of positive pressure in the air intake channel and negative pressure in the conventional air extraction system, the negative pressure in the compartment is little to zero. It is what we call “flat ventilating”. This is the big advantage of the system versus conventional systems: The avoidance of airstreams in your pig stables and 100% usage of the ventilated air.
3. The air extraction is connected via a standard air extraction unit to the central air duct and controlled by a conventional climate control computer. So in the usual way, with minimum ventilation, bandwidths, curves and maximum ventilation settings. The size of the air intake opening is controlled by the same computer in the same way: when increased ventilation is needed, the air intake tube unrolls, causing more holes to open. And vice versa.
4. The positive pressure in the air intake channel is regulated by a second computer using an air pressure detection system that is situated in the air intake channel. When the air extraction system starts to ventilate harder, the air pressure in the air intake tube will drop briefly. This will be read by the air pressure detection system causing the air intake fan to run faster. This will make sure that the air pressure in the air intake channel will be levelled again.
5. Because fresh air is blown into the pig barn via a central air entry space, it is a possible to pre-treat the air there. From the central air entry space fresh air is blown into the air intake channel via a closed tube system into the compartments. The pre-treatment of the fresh air can be cooling/warming, filtering against germs, humidifying/drying, or adding for example oxygen, pheromones or disinfectants.
6. The used and ventilated air is actually waste. There are several possibilities to reduce this waste and to separate it at the source. You can read more about this at the tab “Waste Reduction”.
7. The system cannot be installed in compartments with low ceilings. When increasing air ventilation, the speed of air movement will be too high.