Agriculture Reference
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1.9 l/min kg of dry flying substances at processing mixes which structure includes
manure. At passive aeration speed of receipt of air in compost heaps is insignificant
and makes 0.04-0.08 l/min kg of dry flying substances (Bernal et al. 1993 ; Haines
1995 ). Passive aeration can essentially reduce the price of process in comparison
with compulsory or active aeration. Passive aeration demands for the realization
special aeration channels and appropriate calculation of speeds of the air streams
created due to a difference in temperature between the punched mix and air. To
establish the similar interrelation, modes of temperature have been studied and con-
vection a stream of air in is punched mixes with 3 kinds loading: wooden shavings,
hay and straw and also 3 levels of the contents of humidity: 60, 65 and 70 %. All
experiments were spent in a passive and active mode of aeration. For experiments
laboratory reactors in volume 105 l have been used.
2.3.3
Humidity
Passive humidity of 60-70 % had the temperature peak arising between 2 and 6 day
of composting. After 6 day of composting the moisture content did not render any
influence on a temperature mode of process because of loss of moisture in a mix.
The interrelation between number Grasholff (GR—the relation of buoyancy to force
of internal friction) and speed convection an air stream has been established. Gen-
erally speed convection an air stream varied from 1.5 up to 0.7 mg of dry air/kg s
of dry material compost from 0 up to 20 day accordingly for all samples compost.
This speed of a stream of air was provided aeration with the channels made inside
compost of heaps for passive aeration. In comparison with straw where speed of an
air stream fell below a level of number GR, wood shavings and hay have appeared
are more effective as loading. At use of these substances speed of a stream of air in-
creased constantly together with GR (Altieri and Esposito 2010 ; Sato et al. 2010 ; Yu
et al. 2011 ; Pane et al. 2013 ). On the other hand, advantage of compulsory aeration
is higher speed composting and an opportunity of partial regulation of temperature
of process; lack—significant losses of flying organic substances at carrying out
composting (Brinton and Brinton 1994 ).
Influence of compulsory aeration on a degree of formation of ammonia was stud-
ied at composting waste of housekeeping on pilot installation. It is shown, that
significant clearing NH 3 occurred at the first stages of degradation of fibers and
amplified with increase in speed of aeration during this period. Good correlation
between change of temperature, clearing СО 2 and allocation NH 3 was observed
(Atkinson et al. 1996 ). In this connection separate researchers recommend to spend
composting at passive or natural aeration which though proceeds with slower speed,
but provides fuller maturing compost and does not demand high monetary expenses
(Hemmat et al. 2010 ; Jolanun and Towprayoon 2010 ; Bustamante et al. 2011 ; Tur-
rión et al. 2012 ). Parallel experiments on influence of various kinds of aeration
on quality compost have shown, that any processes of artificial aeration reduce
time composting, however on occassion, can worsen quality compost. It is most
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