FIE1,D OF INVENTION
The present invention relates to compost production for whitc button mushroom
(Agaricu.~ hi.sporus spp) particularly with use of zero energy polytunnel from the
various recommended ingredients like whcat straw, wheat bran, chicken manure, gypsum
etc.
BACKGROUND OF TI-IE INVENTION
White button mushroom (Agaricus hisporus) is the most popular edible mushroom
contributing about 85% of the India's mushroon~ production against its global share of 3 1
per cent. Commercial production of this mushroom represents unique exploitation of the
microbial technology for bioconversion of the agricultural, industrial, forestry and
household wastes into nutritional food. Indoor cultivation of button mushroom, utilizing
the vertical space, is regarded as not only the highcst vegetable protein producer pcr unit
area and time but also contains vitamins, minerals and has low calories with some
medicinal properties. rhis mushroom is cultivated on specially prcparcd selective
substrate known as compost. It is a product of commercially important solid-state
fermentation process based on self-heating and rherrnophilic microbial degradation of the
plant residues and organiclinorganic matters (Van Tier et al., 1994). With rising demand
for mushroom as neutraceutical quality food and higher cost of production particularly
compost production in terms of labour, energy and infrastructure with additional
environmental problems is leading to rclativc decrease in button mushroom production
when compared with total production of different mushroom grown worldwide.
Commonly long (traditional) and short (tunnel) methods are used in many
devcloping countries like India for prcparatioii of button mushroom compost (Vijay,
20 10). I Iowcvcr, some other composting mcthods i.c. complcte indoor method viz.,
INRA (I,aborde, 1991) and Anglo Dutch ((;errits et al., 1993) arc available at some
developed countries like France, Italy, IIolland, Belgium, Austria and Australia. The
basic principles of composting were outlined by Lambert (1941) for long method of
coinposting has been described by Aikins (1966) where it took 4-6 weeks to complete the
process irrespective the different proportion of ingredient used. 111 India, this method was
standardized by Mental et a1 (1 972). Initially wheat straw is wetted for 48 h and then 20-
24 h before making piles various ingredients viz., CAN, urea, murate of potash, super
phosphate wheat bran or brewer's grain were mixed properly. After making heaplpile of
mixed wetted straw, it is turned either manually or mechanically 7-8 times with interval
of 3-4 days to avoid anaerobic condition or till mature compost free from ammonia is
ready. Gypsum was added during 3rd turning. However, two-phase short method of
compost involves, outdoor composting for 10-12 days with 3-4 turnings (Phase-I)
followed by pasteurization and conditioning of compost inside an insulated room by
circulation of air under definite set of conditions known as Phase-I1 (Sinden and Hauser,
1950; 1953). In addition to it, boiler for pasteurization (57°C for 6-8 h) and blower for
conditioning (4552°C for 5-6 days) of compost in short method is one of the energy
consuming operation with additional cost of construction of tunnel. Both 28-30 days long
and 18-20 days short methods are highly laborious and time intensive activities causing
environmental problems (Vestjens, 1994). Stringent laws governing pollution in
Netherlands, Australia and European countries have resulted in closing of many compost
units. This pollution problem in many developed countries was solved by complete
indoor composting methods (INRA and Anglo Dutch). In INRA indoor composting
method 1,aborde (1991), Phase- I (pasteurization) was carried out at 80°C for 2-3 days
and then phasc-I1 (conditioning) at 50°C for 5-7 days. This method is high temperature
process and causes killing of most thermophilic microbes and hence re-inoculation with
pasteurized compost or with a thermophilic fungus S thermophilum becomes necessary
for getting the economic mushroom yield (Van Griensvan, 1992; L,abordc et al., 1993).
'I'hc re-inoculation problem of thermophilic microbes was solved in Anglo- Dutch
method by maintenance of optimum pasteuri~ationte mperature 60°C for 4-6 h followed a
week of conditioning. 'T'his process permits excellent control, substantial saving of raw
material and also increases the biomass of thermophilic organism (Miller, 1997).
Compost produced by both the above methods takes lesser time (9-13 days) as compared
to traditional methods (Perrin and Gaze, 1987. I,aborde, 1994). The composting
procedures thus available are time consuming or are costly and involve lot of
infrastructure.
Ilcncc a technology that may reduce the cost and time of the compost production will
give boost to the production of button mushroom. 'l'he environment fi-icndly compost
methods so far developed by researcl~erst,h ough relate to get quality con~positn shortest
duration for enhancing more mushroom yield, however, it is costly and have not yielded
expected results and solved the cnvironnlcntal problems completely.
BRIEF l)ESCRIPrI'ION OF I)IUWIN<:S:
Figure 1 : Tine drawing of Ihc ~ c r ocn crgy polytunncl compost tcchniclue for
button mushroom. (Front clcvation)
Figure 2: I,ine drawing of' thc Lero energy polytunllel compost technique for
button mushroom. (Front clcvation and side view)
Plate 1 : Zero cncrgy polytunncl for c0111post technique for button musl~room.
SUMMARY OF 'I'IIE INVENrI'ION
'l'he invention providcs a novel improved Lcro cncrgy poly-tunnel technique for making
compost fix Agaricus spp. 'l'his providcs low cost mcthod/tccl~niquc based on the
principles of passive aeration and heat-mass transfer for accelerating the compost
biological activity in a short duration to gct matured compost. 711 this tcchniclue, the
uniform parallel-perforated III)Pl< pipcs arc inserted into compost pilclheap lor
aerationlrcleasc of'exccssivc ammonia and compost pile is covered by polyethylene shcet
placed on flexible GI frame for natural pasteurization and conditioning of compost.
'l'he main object of the invention is to develop a reliable e~lvirollinent friendly low cost
short duration composting 111cthodItccl1niquc based on natural self-heating process of
thermophilic microbes to improve thc profitability of mushroom farming in all agro
climatic regions.
'These and other objects will bcco~ncin creasingly apparent by rcfcrcnce to the following
description.
'l'hc methodltcchnicluc disclosed in the application inserted the parallel-perforated 111)E'l~
pipcs in a trapezoidal shape pilcll~cap,w hich is formed from the prc-wetted mixture of all
7 the raw ingredients used for composting. I hereafter, for natural completion of further
composting proccss i.c. pasteurization and conditioning; pilelheap is covered with
polyethylene sheet and GI frame. 'Thus matured quality compost suitable for button
mushroom mycelium growth is achieved.
In present invention basic compost ingredients viz., wheat straw, chicken manure, wheat
bran, urea and gypsum are used. 'I'his invention can also work for all compost
formulations used for button mushroom. EIowever, selection of compost formulation
depends upon the availability and cost of ingredients. 'To initiate a composting process
and minimi~eth e loss of dry matter during composting, 1.5-1.75% nitrogen is generally
kept in composting mixture. The main objective of composting formulation is to achieve
a balancc between carbon and nitrogen compounds. Ilence at starting C: N ratio is
adjusted to 25-30: 1, which comes down to 16: 1 after completion of composting process.
'I'he nitrogen level at the start should not be less than 1.5% as it gives higher C: N ratio
and such compost easily attacked by the ccllulosc loving fungi. Similarly, it should not be
higher than 1.75% in order to avoid attack of yellow moulds fungi and longer duration of
compost procedure. Accordingly, in prcsent invention, ingredients quantity is adjusted to
get uiliclue compost formulation with initial nitrogen of 1.6 per cent.
'l'he basic ingredients ol'composting viz., wheat straw, chicken manure, wheat bran, urea
and gypsum vary widely in their bioengineering properties, which causes variation in
composting properties and mushrooin yields. Ilcnce, thc bioengineering properties like
avcrage particle size, moisture content, bulk density and porosity, angle of repose, EC
and pII of the ingredientslcompost werc measured using screen analysis, air oven at
60°C, mass volume cylinder methods, natural free fall method, glass elcctrode pH meter
and conductivity bridge respectively. Also design of structure used in present invention
depends on some of the bioengincering properties of ingredientslcompost.
'l'he major steps for design of the zero energy poly-tunnel involves, sizc and shape of
compost pilelheap, materials for pipelstands, spacing between the adjoining pipes and
stands, frame design and selection of polyethylene sheet cover.
'lhe sizc and shape of the compost pile1 heap mainly depcnds upon the particle size and
angle of rcpose of the compost prepared from the various ingrcdients. It is also observcd
that angle of repose increased with increase in composting period. IIencc the minimum
angle of response is used to fix the suitable size and shape of coinpost pile1 heap so that
the compost pilelheap remains stable and should not fall down during composting. 1:or
determining the appropriate slyape, compost pilcs/heaps of thrce different possible shapes
(semicircular, triangular and trape~oidal) were made based on the minimunl angle of
repose of compost with ground surPdcc. Among all thrce pilcslhcaps, trapezoidal shape
compost pile is found more stable and hence this shape was used in the present invention.
Size of the compost pilelhcap and invcntio~z depends upon the demand or compost
rccluircd.
'She reduction of conlposting period is one of the prime need. Coinposting process can be
accelerated by providing sufficient amourit of aeration required for healthy growth of
thernzophilic microbes without decrease in tcnipcrature bcyond a given limit. 'l'hc amount
of passive aeration optimi~ed by illserting perfbraled pipcs wilh various arrangements
naincly parallel, perpendicular and triangular inside the three different trapezoidal shapc
pilcslhcaps. 'l'he effect of' the aeration is also compared with control (pilell~eapw ithout
pipes). Among all the arrangements, parallel arrangement pcrl'ormcd thc bcst. I'hc
spacing between the pipes, s i ~ cof pipes and perforation on pipes were optimi/ed to get
uniform aerated compost by series of passivc aeration compost trials. I'hc initial
temperature during the coinposting is about 80°C. 'l'he materials used for pipes and iron
stands for support and maintaining the spacing between pipcs should have sufficient heat
and corrosion resistance. 'Shus among various pipe materials (PVC, SRS. GT and I-II>PI*,)
used, IIIIPI: is corrosion ficc and capable to bear heat generated inside the compost
pilelhcap. Even though instead of galvanized iron (GJ) stands, IIIlP1: stands can be used
for support and maintaining the spacing bctwccn pipes. IIowever for easy handling and
transportation during the turning of compost, pipcs are cut into 1.8-2 m pieces 2nd joined
with help of collar, which is locatcd at onc end of pipe. 'l'hus spacing between the two
iron stands remains same as thc length of pipe piccc.
l'he sizelshape of (;I framc depends upon the si/c/shape of the compost pilclheap. I Icnce
slightly higher size of the (;I liamc is selected fi~rfr ee air circulation alicr covering it by
polyethylene sheet. l'he Game is made fiom the (;I iron pipcs, ilcxible and dismatltled
easily for handling and transportation. 'I'hc basic purpose of polythene shect cover is to
avoid the moisture loss, excessive drying of opcn surface of pilelheap exposed to the air
and maintain uniform heating inside thc compost pile for pasteurization and conditioning
of compost. 'lhis covcr also acts as insulator and heat retainer during the composting.
Therefore black sheet with enough thickness (50-150 GSM) is selected for covering the
compost pile.
I'hc present invention and process of composting is completely based on the natural
principle of passive aeration and heat-mass transfer. IIeat generated during the
composting is uscd for pasteurization and conditioning and hence it is an energy free
proccss. 'The infrastructure, time and labour requirement is very less as compared to
composting methods in vogue. Aerobic condition maintained using perforated pipes
helps to reduce the offensive smell generated in anaerobic composting proccss. The most
of the ammonia 1 moisture released is re-trapped during composting process which results
in environmcnt friendly operation and better quality and more compost that gives higher
mushroom yields and income than the previous composting methods.
Compost ingredients and their bioengineering properties
'I'he selection of the compost ingredients depends on the availability and cost of
raw materials in a particular region. The most commonly used compost ingredients viz.,
wheat straw (60% weight basis), chicken manure (30%), wheat bran (5%), urea (I .2%)
and gypsum (3%) were selected for composting. This formulation is based on the
optimum initial nitrogen level of compost ingredient mixture i.e. 1.6 O/O for rapid initiation
the compost proccss. 'lhe bioengineering properties viz., moisture contcnt, bulk dcnsity
and porosity, 17C and pH, average particle size, angle of repose of the ingredients were
measured using air oven at 60°C, mass volume cylinder methods, glass electrode pIi
metcr and conductivity bridgc, scrcen analysis, natural free fall mcthod respectively. 'l'he
basic ingrcdients of composting viz.. whcat straw, chicken manure, wheat bran, urca and
gypsum vary widely in their bioengineering propcrtics, which causes variation in
coinposting properties and mushroom yiclds. IIence, thc various biocngineering
properties of ingredients wcrc dcterinincd as they directly affect the bioengineering
properties of compost and mushroom yields ('l'able 1).
Table 1
---
Ingredients
Wheat straw
Wheat bran
IJrca
Gypsum
Chickcn manure
I'orosity
(%)
75.45
7 1.54
46.67
66.08
60.27
pfl E.C. Particle size, nim Anglc of
rcposc (deg.)
42.00
44.00
30.00
33.72
10.67
Thc major steps for dcsign of the Lcro energy poly-tunnel involves, selection of
appropriate sizc and shape of compost pilclheap, standardization of materials for
perforated pipeslsta~~dosp, timi~ationo f spacing between the adjoining pipes and stands,
fraine design and selection of polyethylene shect cover
Size and shape of tlic compost pile
'I'he size and shape of the compost pile1 heap mainly depends upon angle of
repose of' the compost prepared fiorn the various ingredients. 'The angle of rcposc of'
compost varics with the composting period and bioengiilcering propcrtics viz., moisturc
contcnt, bulk dcnsity and particle sizc of co~llpositn grcdients. Anglc of rcpose along with
some bioengineering propcrtics of'cornpost wcrc nleasured with interval of5 days till gct
natured compost was obtained Srom both short and long methods ('l'able 2).
'I'able 2
Compost
Pcriod
0 days
5 days
10 days
15 days
20 days
25 days
30 days
Long method
(degree ) (w b.) (kg/m')
Angle of repose M.C.'% 13ulk density ,
42.5 1 74.78 G 8 66
43.5 1 74 14 416.66
45.59 71 07 420.03
48 60 68 22 412 00
52 12 67 95 390 20
52 25 67 30 378 70
Short m. et-h od
Anglc ofrepose M.C %
(dcgrec. (w.b.)
--
42.46 75.21
43 62 72.09
45.64 7 1 .OO
48 58 69.04
51 91 68 12
Bulk dcnsity
(kg/m')
446.07
415.78
437.54
398.06
359.84
For this purpose compost made by using formulation discussed in Example 1
from the one ton of compost ingredients in each method separately. It was found that
moisture content, bulk density of the compost decreased with increase in composting
period, however bulk density increases slightly after addition of gypsum on loU' days. It
was also observed that angle of repose increased with increase in composting period and
almost bccomcs constant i.e. about 52" after 20"' days. Hence the minimum angle of
response i.e. 42-45" which can be used to iix the suitable size and shape of compost pile1
heap so that the compost pilelheap remains the stable and should not be fall down during
the composting.
Size of the compost heaplpile depends upon quantity of ingredients for compost
production as per requirement. While forming the compost heaplpile angle of repose (42-
45") i.e. angle made by slanting side of the pilelheap to the ground surface is important
for stability point of view. Thus for getting the angle of repose i.e. 42-45" with ground
surface, approximate width 2.75 m and height 1.4 m of pilelheap was calculated. For
commercial purpose length of pile betwecn 6 to 16 m is commonly preferred. Elence,
based on scrics of experimentation with consideration of angle of repose (42-45"), best
size i.e. 10 m length x 2.75 m width x 1.40 m height of the heaplpile was conformed for
the present invention. For determining the appropriate shape, compost pileslheaps of
three different possible shapes (semicircular, triangular and trapezoidal) of mentioned
size were made from uniformly well-wetted ingredients mixture (initial moisture level
about 75%. w.b.). Among all three pileslheaps, trapezoidal shape (10 m length x (0.75 m
top t 2.75 m bottom) width x 1.40 m height) of capacity 7.5-8 ton compost was found
more stable and hence this is best shape and size used while designing the present
invention.
Standardization of pipe materials, pipe parameters and pipe arrangement
'I'he reduction of composting period is one of the prime objectives of the invention. 'I'his
can be achieved by providing sufficient amount aeration (10-15% O2 level) for
accelerating the themophilic growth and rapid completion of compost process. It was also
noted that initial temperature during the composting is about 80°(3. 'fhcrcforc the
materials used for pipe must have a sufficient heat and corrosion resistance. 'She difr'ercnt
pipc materials viz., I'VC, SRS, GI and IIDPE were tested insidc thc compost pilelhcap.
Among thc testcd materials, IIl>I'I: pipc with 6-10 mm thickness was found to be
corrosion free and capable to bear load and heat generated inside the compost pilelheap.
Also, for uniform passive acration purposcpcrf'orated IlDI'1; pipes with various possible
arrangements namely parallel, perpcndicular and triangular were inserted longitudinally
inside thc threc diffcrcnt trapczoidal shape pilcslhcaps of s i ~ c10 m length x (0.75 111 top
12.75 m bottom) width x 1.40 111 height. Optimization of various pipe parameters namely,
percentage-perforated area of pipe, spacing betwcen the pipcs and size of pipcs and
perforations for maintaining the rccluircd oxygcn level (10-1 5%) arc necdcd. All these
pipc parameters were optimi/.cd by the series of cxpcriincntal trials by using possible
pipcs arrangcinent as mentioned previously. A1 the samc time the effect of the passive
acration was also compared with control (pilelheap without pipes). Among the all 1 I1)Pl~
pipcs adjustmcnts, parallcl arrangement with 10% perforations was found best in term of
shortest compost maturity period (1 6 days) followed by triangular with 10% perforation
(22 days), pcrpcndicular arrangcmcnts with 5% perforation (24 days) and control (28
days), respectively l'he corresponding pipes sizc (1 0.15 cm diameter) and pcrforation
sizc (4 cm diameter) with spacing 8 cm was noted in parallel arrangement. It was also
found that the pipc of this s i x acratc (10-1 5 %02 level) about 0.3 m radial distance of
compost pilclhcap. Thus the spacing between adjacent pipcs was fixed as 0.6 m. Also for
uniform acration &-zag parallel arraiigcmcnt of III>PI< pipcs was used. 'lhc number of
pipcs was calculated based on the cross-section area of the trapezoidal shape pilelheap
and spacing between pipes (0.6 111). 'l'hus out of 6 pipe lines 3 were arrangcd at the
bottom zonc, 2 werc at middlc mnc and 1 was at the top zonc. Thc length of cach
pipeline was about 10 m. Ilowevcr for casy handling and transportation during the
turning of compost, each II1>1'1< pipcs lines cut into 1.8-2 m pieces and joincd with help
of collar, which is located at one end ol'pipe.
Frame Ilesign and polyethylene sheet parameters
'She sizelshape of GI frame mainly depends upon the sizelshape of the compost
pilelheap. Ilence almost same size of frame i.e. 10 m length x (0.90 m top -t 2.75 m
bottom) width x 1.6 m height as of pilelheap with slightly increase height was selected
for free air circulation after covering it by polyethylene sheet. 'The frame made from the
corrosion and heat resistance GI iron pipes, flexible and dismantled easily for handling
and transportation. 'This frame itself acts as stands for support and maintained the spacing
between the pipes shown in the Fig. 3
'I'he basic purpose of polythene sheet cover is to avoid the moisture loss,
excessive drying of open surface of pilelheap exposed to the air and to maintain the
uniform heating inside the compost pile for pasteurization and conditioning of compost.
'l'liis cover also acts as insulator and heat retainer during composting. Therefore, black
sheet with enough thickness (50-150 GSM) was selected for covering the compost pile.
The size of the polythene sheet i.e. 5.5 m x 10 m was calculated from frame with
additional two flaps at the end of trapezoidal GI frame.
Working principle, process of composting and successful composting in different
season
'I'hc working of this invention is based on the principles of natural passive
aeration and heat and mass transfer. Because of temperature difference between
atmosphere and compost pilelheap, the bottom three lines of perforated pipes suck the air
fiom outside atmosphere for accelerating the compost thermophilic fungi activities. The
result of rise in temperature of compost, air inside the compost gets heated and moves
upward by convention. This heated air finds its way to go out through middle two and top
perforated pipes lines. I-Iowcver two middle pipes also lines suck the outside air as well
as releases the hot air from the pilelheap. 'Shis natural flow of the air is continued during
the entire compost process. Also some amount of heated air carrying the ammonia1
moisture released during cornposting is trapped in surrounded polythene cover of
compost pilelheap. 'I'his helps to raise temperature of the surface layer of the pileslheap
for proper pasteurization and conditioning ol' compost. I'l~us all compost operation v i ~ . ,
uniform aeration, pasteurization and conditioning during the composting are maintained
naturally using IIIII'E perforated pipes and polyethylene cover. Hence this invention is
named as zero-energy polytunnel for button nlushroom composting. Detailed of the Leroenergy
polytunnel tcchniclue Sor composting is given in the flow chart.
Process of composting used in this invention involves formation of trapezoidal
hcapslpile by inserting the perforated IIDI'F pipes in parallel zigzag arrangement fiom
the properly mixed pre-wetted compost ingredients for 24 h, natural pasteurization by
covering of compost pilclhcap with polythcne sheet for 2 days at 66-72OC and opening of
side cover for conditioning at 50-60°C.' of compost for next 2 days. 'I'hereafter tirst
turning of compostlpilc on 6''' days and formation of pile with pcrforated I II>P1< pipcs,
second natural pastcuri~ationb y covering of compost pilelheap with polythene sheet for 2
days at 60-6S°C and conditio~iing of compost pilelheap for next 2 days at 52-54'C,
second turning on I lth days, covering ol' compost pilelheap for next 2-3 with polythcne
cover without closing the sides for conditioning at 48-52'C. Breaking and spreading of
matured compost pilclhcap for ovcr night cooling, spawning and filling of compost
bagslbcds.
Well-established zero-energy polytunnel technique for compost production was
tested in different timc of' thc year. I>ifferent seasons considered were summer (March-
May). rainy (June-September), wintcr (October- February). l'hc compost was produced
successfully with improved tcchniquclprocess under discussion for button mushroom.
'I'hus establishing thc cf'f'cctiveness of thc innovation ovcr the different season under
natural condition stands.
Pre-wetting of straw - -Mixing of ingredients (chicken manure. wheat bran, gypsum, urea)
I I
/ Mixing of straw - ingredients I
+
Wetting of straw - ingredients (72-75% moisture) for 24 h
4
Pile formation with ~erforatedH DPE uiues and covering with black ~olvthenesh eet and GI frame
1
Satural pasteurization at 66-72OC for 1 day
+
I Natural conditioning at 50-60°C- opening of side flaps black pp sheet for 3 days
I 1 It turning and pile formation with perforated HDPE pipes and covering with black polythene sheet and GI frame /
2nd natural pasteurization at 60-68OC for 2 days
4
2nd natural conditioning at 50-54OC- opening of side flaps of black polythene sheet for next 2 days
1
2" turning and pile formation with ~erforatedH DPE pipes
prd natural conditioning at 48-52'C- opening of side flaps black pp sheet for next 2 days /
7l Break the pile 1-
I Spawning 1
Spread the compost over night
And Formalin treated floor if no NH3 4 Pile formation if NH3 for another 2 days
Platc 1 : Zcro energy polytui~nclf or coinpost tcchniquc for button mushroom
Example 6
Comparison of traditional methods with the new methods
In order to compare the present invention with traditional (long and short)
methods various parameters viz., c;fbposting production cost, physio-chemical
properties of matured compost and mushroom yield were measured. It is well established
fact that some physio-chemical properties of matured compost viz., moisture content pH,
bulk density, ammonia are used to check the maturity of compost. For matured compost,
the standard values of moisture content (58-68% w.b.), pH (7.2-7.8), bulk density (450-
550 kg/m3) and ammonia (5-8 ppm) rcquired for appropriate mycelium growth. Detailed
comparison of existing traditional composting methods with the new method in terms of
various parameters is given in the Table. 4
- - -. . -- - - - -
S. No. Parameters to he compared Zero energy poly-tunnel Short method Long method
1 Composting period (days)
-
2 Average mushroom yield 22-27 18-22 15-18
(Per cent /quintal of compost)
- -
3 Cost of compost production 175 330 269
(Rupees1 quintal of compost)
- -
4 Producers Seasonal/ mcdiurn Co~n~nercial Seasonal and
growers and commercial units medium
units growers
5 Physio-chemical properties of matured compost
Moisture content (w.b.), %
Bulk density (kg/m3) 320-480 320-450 350-430
C: N ratio
Benefits of zero energy poly-tunnel as compared to the traditional met11 od
J This technique reduces about 47% and 35% compost production cost as compared
to short and long method
J 'This technique reduces 60% and 40% composting period as compared to the long C
and short method
J This is natural and environment friendly composting process and recluires only 2
manual turning without additional infrastructure i.c. coclpost yard, tunnel, boiler
and blowers, etc.

We claim
1. A method of compost production for button mushroom yield enhancement
wherein said method is not dependent on season involving use of zero-energy
polytunnel, comprising the step of:
,forming trapezoidal heaps/pile JFom he properly mixed pre-wetted compost
ingredients by inserting perforated pipes in parallel zigzag arrangement
natural pa.steurizution by covering oj'compost pile/heap with polythene sheet .for
2 dayYr at 66-72°C and opening of' side cover ,for conditioning at 50-60°C of
compost, for next 2 days
first turning qf compost heapbile on 6Ih days and w i n formation ofpile with
perforated JDPE pipes
second natural pu.steurization by covering of compost pile/heap with polythene
sheet ,for 2 days at 60-68OC and conditioning of compost pile/heap.for next 2 days
at 52-54°C
second turning on I l t h day.^, covering qf compost pile/heap for next 2-3 with
polythene cover without closing the sides for conditioning at 461-52°C
Breaking and spreading of matured compost pile/heap for over night cooling,
spawning and filling of compost bags/beds.
2. The method as claimed in claim 1 wherein said trapezoidal shape pile of size 10
m length x (0.75 m top t 2.75 m bottom) width x 1.40 m (height). However length
of pile varies from 6 m to 12 m based on quantity of compost required.
3. The method as claimed in claim 1 wherein said compost ingredients are wheat
straw (60% weight basis), chicken manure (30%), wheat bran (5%), urea (1.2%)
and gypsum (3%)
4. 'I'he method as claimed in claim 1 wherein said perforated pipes (10-15 cm
diameter, 6- 10 mm thickness and 1.8- 2 m length of each pipe piece) are made of
high-density polyethylene (HDPE) material of 10% perforation with respect to
total longitudinal cross section area of pile.
5. 'I'he method as claimed in claim 1 wherein said polythene cover is made of black
IIIlP1) material of thickness (50-150 CiSM). The cover size (5.5 m x 10 m) is
calculated from Sramc of s i ~ c10 m length x (0.9 top 1 2.75 m bottom) width x 1.6
m height with additional two flaps at the end of trapezoidal GI fi-ame.
6. 'l'he method claimed as in claim 1 is based on natural principle of passive aeration
and heat and Inass transfer for accelerating the compost biological activity in a
short duration to get matared compost in 12-16 days. Perforated pipes inside the
pile and polycthylcne cover help to achieve uniform pasteurization and condition
naturally.
7. A method of zero energy poly-tunnel for button mushroom conlpost production
substantially as herein described with reference to acconlpanying drawings and
examples.