39 Aerated floors create more homogenous compost and an easier to steer process.
hay and corn husks in a windrow (wit- hout an aerated floor). Whether or not the windrow is turned on a daily basis makes a huge difference. Sufficient oxygen during pre-wetting and the first phase of the com- posting process is crucial for an optimal process. In other words; how often the is compost ‘stirred’ before forced aeration is applied.
Are compost temperatures in excess of 80 degrees Celsius necessary for an optimal com- posting process? The jury is still out on this question. Some think the compost temperature during composting should not exceed 80 degrees, while others are convinced that the higher the temperature gets, the better it is. I be- lieve that in both cases oxygen has a grea-
ter influence than a temperature that is just above or below 80 degrees. The system used in the process also impacts strongly on the process itself. For example, in a tun- nel for phase I with constant aeration lower compost temperatures are needed (75 - 78 degrees) due to greater homogenity in the oxygen supply. In a closed system, a relatively high oxygen content can be used without blowing ammonia or moisture out of the compost. I have seen some very good results on compost with temperatu- res above and below 80 degrees during composting. Even the windrow composting system, considered by many to be ancient history, can book very good results – com- parable with those of bunker composting. Composting in tunnels or bunkers carries less risk, thanks to the greater accuracy of process control, improved homogenity and
the virtual eradication of weather influ- ences. As far as lower compost tempera- tures in bunkers (below 80 degrees) are concerned, I believe this involves greater risks, which become manifest in compost that is too hard, containing little or no built- in moisture. The compost is also often too greasy if the compost temperature does not go beyond 80 degrees. Whatever system you use, monitoring the oxygen content properly during the process is critical. The value of the oxygen content depends on the phase in the process. When the compost is being heated up in bunkers or phase I tunnels, more oxygen is required than when the compost temperatures are higher than 75 degrees. What is clear to me is that compost left without ventilation will soon begin to suffer from an oxygen deficiency. An oxygen deficiency at any stage always harms the process, and quickly results in lower production.
How essential are compost temperatures above 80 degrees Celsius?
Does straw have to be pre- wet or are production results practically identical without pre-wetting straw? Opinions are divided about this matter too, and in many cases, a pre-wet system is chosen. But you can still get some great results without pre-wetting! The various raw materials such as American hay, straw, corn husks and rice straw each require a different pre-wet time and treatment before they can be mixed with other raw materials. In Spain and the USA there are companies with a pre-wet system that first wet and soften the straw before the poultry manure is added, and other companies in the same country that omit the pre-wet phase altogether. In the latter case, the mixed raw materials are usually blended and turned on an aerated floor right from the start. Both approaches give excellent results, but on close scrutiny there are variations in the small details. For example, the compost temperature in a bunker rises faster if the straw has been pre-wet. And if pre-wet is omitted, the volumes will be far greater the first time the material is filled, provided the straw has not been chopped. A typically used system originating in Italy chops the straw a little shorter before adding the poultry manure, which means that more dry matter per m2 can be filled later on in the cultivation process. And despite the shorter structure, it is still possible to force enough air through the compost during the bunker process if the bunker is not filled too high. In both cases, with or without pre-wetting, optimally blending the raw materials is vitally important to achieve the very best production results. In principle, compost producers can exert a significant influence on the ultimate result (mushroom production) before the bunker is filled, namely during the preparation
>
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44
