Large surfaces need large machines Automated steaming was developed already 20 years ago. For large machines, the main challenge is to treat the largest surface and to consume minimum energy to ensure economic operating. Nowadays, three series are available: SEMI AUTOMAT MSDA 600/800: MSD, 2016 STEAMING ROBOT MSDZ-1: MSD + J. Zeyer, 2016 DÄMPFMOBIL: MSD + Bärtschi Fobro (CH), 2010 STERILTER: MSD + Ferrari (IT), 2004 Steaming plough, MÖSCHLE, 1992 Remember that you need up to 20 tons steam for each hectare to efficiently sanitize the soil. For effective weed control, the steaming depth should be ~6cm. That means high requirements both on steam generation and stream transfer into the soil.
As an alternative to a fully automatic steaming solution MSDZ-1 which use self-propulsion and require no machine operator to treat surfaces with steam, MSD has also developed semi-automatic steam systems. The latest range of these MSD machines were launched in August 2016. In contrast to the fully automatic steam machines listed below, the semi-automatic machine is drawn over the beds by a towing vehicle, e.g. a standard tractor. The steam hoods of the semi-automatic machine are lifted and lowered via a hydraulic system. Steam generation and feed is controlled fully automatically. The system runs self-sufficiently on fuel oil and electricity. Water is supplied continuously via a PE pipe.
Semi automatic steaming machine in operation, video on YouTube: https://www.youtube.com/watch?v=Dy5flmoHHYY Semi-automatic steam machine The semi-automatic steam machine is available in two sizes. The smaller version has a steam performance of up to 600kg per hour. The larger version has a steam performance of up to 800kg per hour. A machine like this can completely free a surface of up to 18m² of weeds in around 5 minutes, with a steam depth of 4-7cm.
One of Europe’s largest producers of salad leaves ordered a new edition of the steam robot series from MSD as a replacement for the “Dämpfmobil” (Steam Mobile) from 2010. The requirements were higher. Impact was to be increased by at least 30%. In addition, the stricter requirements for a fully automatic field robot as imposed by the authorities had to be fulfilled. Thus the fully automatic steam machine MSDZ-1 came about, designed and constructed together with the Josef Zeyer Agrartechnik company from Neresheim. The fully automatic steam robot lowers, lifts and moves the steam hoods independently and does not require operation by a driver. The machine’s steam performance has been increased by just under 40% and it can therefore steam-treat larger surfaces significantly quicker than the previous model from 2010.
Fully automatic steam machine MSDZ-1 in operation, video on YouTube: https://youtu.be/KSZzz1M9fhE Further, the MSDZ-1 impresses with the latest technology, in particular with regard to approach area monitoring and tracking control. The machine also has its own remote control, which enables immediate intervention at a distance. The fully automatic steam machine can also easily be fitted with GPS navigation.
After the ragwort scandal in 2009, one of the well-known large-scale suppliers of salad had an idea to introduce a clean and high-efficient weed control with hot steam at various plantations. The MSD Company was awarded the contract for development a new machine which could fully automatically treat soil beds on truck fields. The result was the ‘Dämpfmobil’ device, which has successfully been in use since 2010. Various further-developments were necessary to let the device be approved by the trade association and to get the certificate that the machine can be used on open surfaces outdoors without permanent supervision. Similarly to STERILTER, the steam penetrates into the well-loosened soil via hoods. The central control system automatically regulates all processes except turning the machine around at the end of the bed. The ‘Dämpfmobil’ lifts up, moves and lowers the hoods automatically, starts and stops itself without the need of control or actuation by an operator. If troubles occur, the system sends an error message to the operator’s mobile phone, if desired. The desired steaming depth can be simply pre-set for the determined steaming time on the touch screen. So the labour costs are almost negligible in this surface steaming method. The operating cost of this fully automatic machine is about 2,500-3,000 per hectare for weed control at 5-6 cm steaming depth. It is the first time when the weed control with hot steam is possible at such a favourable price!
“Dämpfmobil” in use, video in YouTube: http://bit.ly/daempfmobil In 2010 and 2011, the ‘Dämpfmobil’ machine was awarded with a prize THREE times. Our automated machine won the international INDEGA Innovation Award for Technical Progress as an outstanding innovation at the IPM Fair in Essen (Germany) in 2011. Moreover, it won the TASPO RAM Award for being the best innovation in horticulture. The German Federal Ministry of Food, Agriculture and Consumer Protection awarded our technical innovation with the GERMAN INNOVATION PRIZE IN HORTICULTURE 2011.
The new development of a new fully automatic machine became possible thanks to the invention of a spiked hood. In co-operation with the Italian specialist Ferrari Construzioni in Guidizzolo, we developed a steaming automatic machine equipped with a front hood for use on non-tracked surfaces. Unlike the continuously-running previous MÖSCHLE model, this large machine transfers the steam into the soil to even 25 cm depth by means of a spiked hood. During the steaming time (5-10 minutes), the hood does not move. As soon as the action is completed, the hood is lifted up, offset and lowered again. A central control system regulates all the processes. Due to the machine’s fully automatic running, the operator has only to place the Sterilter device at the edge of the surface to be treated with steam. The same applies to the ‘Dämpfmobil’ device for tracked surfaces, which is described below. The tracers installed on the both sides of the steaming hood ensure that the track is maintained during the machine run and the entire surface is fully automatically steamed by Sterilter.
The development of the fully automatic steaming machines began at Möschle in Ortenberg (Germany) in 1995. The company was inherited by MSD GmbH. Besides the fully integrated structure with all components, especially steam boiler, heating oil, water pre-treatment, water supply and steaming system on a carrier vehicle, it was also important to ensure a continuous steam transfer into the soil. This is the difference between the first large device and all its successors. While the machine moves slowly, the steam is transferred into the soil to the desired depth by means of a special steaming plough hood with injectors. The deeper the steam penetration, the lesser surface can be steamed per hour. br> Till this day, this method is still used for baby-leaf salad cultivation and in Spain. The device performs a fully automatic deep steaming with a crawler vehicle and a stationary mounted steam boiler of 1.2t/h performance.
The mounted spade machine loosens the soil to maximum 40cm depth. Then the steam is transferred to this depth by a steaming plough of 3 m working width coupled with the spade machine. The operating speed can be from 15m (40cm/90°C) to 100m/h (~15cm/80°C) depending on the steaming depth and target temperature.
To keep the temperature high as long as possible after the treatment, the treated surface is to be covered with a drag sheet.