Cleaning at Blow Room and Cards in Relation to the Nature of Trash in Cotton: Part I - Assessment of Trash Content

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Indian Journal of Textile Research Vol. 3. June 1978. pp. 29·35

Cleaning at Blow Room and Cards in Relation to the Nature of Trash in Cotton: Part I - Assessment

of Trash Content

A.K. GUPTA. A.R. GARDE &J.M. GROVER·

Ahmedabad Textile Industry's Research Association Ahmedabad 380015

Received 1January 1978;accepted 5March 1978

A method has been evolved for quantitative analysis of various types of trash in cottons. and in blow room and card wastes. The method involves division of the total trash into ten different categories. Analysis of several Indian cottons has showA that seed coats (fuzzy seed fragments adhering tenaciously to fibre clusters) form the largest single constituent of trash. The proportion of seed coats varies from 45 to 75%, depending upon the variety of cotton. The b1pw room machines have been found to be less effective in removing seed coats than the other types of trash like seeds,leafy matter, soil, dust, etc. The cleaning efficiency of the blow room is, therefore, related to the proportion of seed coats in cotton. The trash portion of Ilat waste in card contains about 85% seed coats, the waste at licker-in being similar to that in other blow room machines. However, the lint to trash ratio in Oat waste is much higher than at the licker-in, with the result that the proportion of seed coats removed at Oats is only marginally higher than that removed at the licker-in.

Considerable work has been done on the assessment of the extent of cleaning done at blow room and cards in mills, and method:>have been suggested for improving it. Most of thesestudies involved quantitative assessment of total trash in cottons using a trash analyser to determine the cleaning efficiency.

irrespective of the nature and proportion of different types of tJ'(ishpresent in different cottons. or remov~Q by different blow room machines. The onlvwork,on the determination of the nature of trash was done in 1928-30by Pein.:eet al". This pioneering work on the blow room practices was done before the development of the Shirley analyser. Of the several interesting conclusions drawn from this study. a major one was that the cleaning achieved in the blow room of the mill is not related to the trash in mixing. This. conclusion was found inapplicable to the Indian blow room practices. as sho~n by the work done in thi~ laboratory(A Tl RA) in 1955-602.3, and later in the laboratories of the South India Textile Research Association (SlTRAt, where the cleaning efficiency was found to increase with increase in the trash content of the mixings. No attempt has been made so far to explain why the blow room behaviours are so

·Present address: NITRA, New Delhi

different. In fact, there appears to he a good case for reassessing the nature and extent of cleaning in the blow room for the following reasons: (a) The discrepancy between conclusions from data of Peirce and those obtained at ATIRA; (b) situations encountered in mills where 'norms' for -cleaning efficiency and waste established at ATIRA cannot be satisfied; (c) occurrence of a large percentage of trash even in long stapled cottons (of Indian origin).

where good cleaning becomes vital; and (d) to achieve satisfactory levels of cleaning for open-end spinning.

, In this context. it was felt that a study of the nature of trash present- in the cottons currently cultivated in India and the removal of different types of trash by the existing blow room and cards would prove useful in optimizing cleaning. A better understanding of the phenomenon of cleaning can also possibly lead to the development of equipment better suited for the removal of trash from Indian cottons.

A procedure developed for the quantitative assessment of types of trash in cott9n or waste samples is described in the present communication.

The results obtained in respect of the nature oftrash content in cottons and on the efricacy or removal of these types at the blow room and cards are pre-

29

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INDIAN

J

TEXT, RES" VOL. J,JUNE IlJ7X

SCllll'd and discu~sed .• The cleaning behaviour of Illdlvtdual blow room machines and of the licker-in and t1ats at the card has also been studied.

•

25 MESH

52 MESH

60 MESH 10 MESH

36 MESH

Fig.2--Leafy matter and stalk A sample of 1000 g cotton or 200 g waste is

taken and full seeds and matted fibres are first separated by hand.

The cotton sample is then passed through the Shirley analyser using the normal short sequence in which the cotton sample is passed only once through the Shirley analyser, but the trash collected after the first passage is passed once again. The waste sample is manually agItated to remove much of the dirt. which is kept separately and the fluffy waste is processed through the Shirley analyser in the same way as the cotton sample.

The trash from the Shirley analyser is passed through a sieve having about 0.5 cm diameter holes. In the case of waste samples, the dirt separated manually is added to the Shirley trash before sieving.

The material remaining above the sieve is termed. 'seed coats' because it contains mostly fuzzy broken seeds.

The material collected below the sieve is further passed through six sieves of pro- gressively smaller mesh size: 10 mesh ( 150011), 25 mesh (60011), 36 mesh (420,L (i)

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Quantitatiw Assessment of Types of Trash The method developed for separating the trash present in cotton or waste into its different com- ponents consists of the following steps:

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1-

>

^72.MESH

Fig.3-Sand, soil and dust

52 mesh (300/1), 60 me~h (250 11),and 72 mesh (21011). The total trash in cotton is thus divided into 10 different categories:

Full seeds, matted fibres, seed coats, 10 mesh, 25 mesh, 36 mesh, 52 mesh; 60 mesh, 72 mesh and >: 72 mesh. The appearance of various types of trash is evident from Figs 1-3.

72 MESH

SEED COATS MATTED

FIBRES

Fig.I-Matted fibres, full seeds and seed coats FULL SEEDS

30

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11

Types of Trash in Bale Cotton

In routine testing, cottons are analysed only for the total trash content and the quantity of waste extracted at blow room and cards is calculated on the basis of this total trash. However, one ,may expect different varieties of cottons to differ in respect of the nature of trash due to diverse genetic and ginning conditions. If the types of trash were to be different, the cleaning behaviour in blow room and cards may also differ considerably between cottons, and different treatments would presumably have to be given for obtaining optimum cleaning. With this in view, a number of cottons from coarse, medium and fine groups were analysed. The compositions of trash by weight are given in Table 2 along with the number of samples tested. It is evident that the cottons differ considerably in the proportion (by wt) of various types of trash. The proportion of seed coats which is the major constituent of trash in all cottons varied from 44 to 76%.

The proportion of seeds varied between nil and 1% in cotton, and formed up to 25% of the total trash in the cotton. The proportion of matted fibres is generally seen to be negligible. The 25 mesh and

> 72 mesh portions constitute a substantial part of the remai~ing trash. The other meshes individually constitute very little and, therefore, the data in the subsequent tables have been grouped in two groups, viz. 10-36 mesh and ) 36 mesh. No appropriate statistical test has been evolved so far to test the

homogeneity of proportions by weight.

Ash content,%'"

5.2 5.4 6.3 7.0 14.2 26.8 28.8 36.2 48.0 63.1 71.9 Moisture

content,%

7.9 11.3 12.0 7.8 9.5 12.0 11.8 10.8 8.5 7.2 6.1

Table

I

-Ash Contents of Cotton and Various Types of Trash

Sample

Lint Full seeds Seed coats Matted fibres

10mesh 25mesh 36 mesh 52 mesh 60 mesh

72mesh

>72 mesh

·On dry weight

GUPTA et aI.:CLEANING AT BLOW ROOM &CARDS IN RELATION TO NATURf.,OF'TRAsH: PART I The seeds are whole or nearly whole cotton seeds general heaVIer than the organic 'Patter and,. there- with small fibr~us attachments. The matted fibres fore, less b\1oyant, it may be expectcihhat the ts,;ash are clusters of immature fibre curled around to form with higher ash cOIitent would be easier to~ove.

a lump. The seed coats are seed fragments adhering However, trashes with equal aSh,content ~ not tenaciously to clusters of short fibres; these are seen be equally easy to remove, since difi:ererit 1'<srms of, later in the flat waste at cards as small specks, trash can have widely different b~yancie~Cert."

generally known as 'kitties'. The 10 mesh, 25 mesh, other factors li}{ebinding force \ltween seed and 36 mesh. and 52 mesh portions consist of the lighter fibres, extent of entanglement of trash in cotton.

trash composed of leaf fragments, stem particles, etc., may also affect trash removal. The cohesion etc. As the mesh number increases (mesh size between fibres and between fibres and trash par- decreases) the trash is relatively heavier and 72 mesh ticles can be more if the moisture content ip> the onwards the trash consists primarily of heavy sand trash type is high. The data in Table 1 show that

and soil dust. seed coats and 25 mesh and 36 mesh trash have a

The classification of trash into various categories high moisture content (-12%); as against this,'the merely on the basis of particle size would not normal moisture content in the lint is about 8%.

necessarily give sufficient information regarding To assess the reproducibility of results, repeat ease of separation of different types of trash. To analysis was done fora number of samples. The gather some information regarding the nature of repeat values, in general, were foUJ4i to lie within each type of trash, the ash content and moisture

±

5% of the first set of values and thuSthe procedure content of eaCh were determined. Trash samples used for separating the trash into different obtained by fractionating blow room waste were categories can be considered fairly reproducible and analysed by burning a known weight (2-3 g) of reliable.

sample of each type of trash. The moisture content of the samples was determined separately by drying at about l05°e for about 3 hr and the ash content was expressed as percentage of dry weight. For each type of trash, two samples were taken for ashing as well as determining the moisture content. The two individual values for~othand for each type of trash were found to be within±IO% of the mean. There- fore, only the average values for two samples are given in T.1l>k 1. It is seen that the ash content in trash increases as the mesh size decreases (or the mesh numberincreases). The higher ash content for material of lower mesh size is due to the higher proportion of non-burnable inorganic matter like sand, soils and dust. The inorganic matter being in

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Table 2 - Proportions of Differeut Typesof Tnsh in CottoDs V797

DigvijayCJ73Sankar-4^CO2Hybrid-4 Varalaxmi Suvin No. of samples

1 8 1

43 1036 Seeds, %

0.4 0.60.60.9^0.30.3

-

0.7 Matted fibres, %

-

^0.1

-

0.10.2^0.4

-

0.2 Shirley trash, %

8.0 7.6 4.0

6.2 4.06.13.4

2.8 ^-t

Shirley

trash composition, % Seed coats

44.049.058.061.567.275.6 45.0 41.0 10 mesh

9.5 3.6 4.4 2.8 2.72.21.8 11.9 25 mesh

24.611.012.4 9.46.86.3 17.1 16.9 36 mesh

4.3 7.18.5 4.25.33.73.4 6.9 52 mesh

3.0 4.0 4.73.5 3.02.62.6

4.2 60 mesh

2.7 3.6 2.6 3.0 2.33.12.21.8 72 mesh

1.7 2.9 1.8 2.0 1.81.01.4 1.6

>7i mesh

8.317.0 17.5 9.211.014.17.5 7.2

INDIAN J. TEXT. RES., VOL. 3, JUNE 1978

It is interesting to note that though Hybrid-4 Table 3. The trash in the waste removed by different cotton is of the same species as Sankar-4, it contains blow room machines contains only 35-45% seed a much larger proportion of seed coats. This may be . coats, inspite of the fact that about 55% seed coats due to poor ginning conditions for Hybrid4. This, were present in the trash in the cotton fed to the

however, has to be confirmed through suitably blow room. This indicates non-preferential removal ,.- designed experiments. It may also be worthwhile to of seed coats at blow rooin compared to the other

study the effect of roller gin vs saw gin on the types of trash like seeds, leafy matter, matted fibres.

proportion of seed coats. The cottons may also vary soi~dust, sand, etc. Though the trash composition in respect of the proportion of seed coats due to of waste from various machines is more or less genetic conditions which may give rise to different similar, the data are indicative of preferential degrees of attachment between fibres and seeds and removal of seeds and matted fibres by Kirschner attack by pest. Cottons in which fibres are held beater and heavy sand, soil, dust, etc., by the more firmly by the seed are expected to give higher supercleaner.

proportion of seed coats. The proportion of leafy Cleaning of cottons with different seed coat con- matter, stem particles, soil, dust, etc., may depend tents -The analysis of blow room waste samples

upon the picking conditions. suggested that a study of the cleaning efficiency for / cottons differing widely in the proportion of seed

Nature of Cleaning in Blow Room coats would be worthwhile. For this purpose, two Nature of trash in waste -The analysis of waste cottons, Hybrid-4 and Suvin, which were expected samples from, a typical mill blow room is given in to contain about 75% and 50% seed coats re-

40.5 37.6 18.8 Kirschner

beater 11 0.4 9.4 0.9 24.7 65.0 43.4

38.0 16.7 Kirschner

beater 1 0.2 25.0 22.8 9.3 42.9 45.7

33.2 17.6 45.8

36.7 22.1 35.3

33.9 27.7

Table 3 - Proportion of Different Types of Trash in Blow Room Waste (30s mixing: 40% Co2, 40% Sankar-4, 20% Digvijay)

Super- Vertical Porcupine

cleaner opener opener

4.0 1.2 0.9

18.4 20.7 23.6

5.4 5.9 10.5

9.1 17.5 9.5

67.1 53.9 56.4

Trash analysis

Overall cleaning efficiency of B.R., 68.1%

Waste, % Lint, % Seeds, % Matted fibres, % Shirley trash, %

Shirley trash composition, % Seed coats

10-36 mesh

>36 mesh

32

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33

Table 4 - Effect of NabD'e of Trash in Cottons on Blow Room Cleaning Efficiency Trash analysisZig zagStriker PorcupineHybrid-4opener KirschnerFini.herbeater

cleaner

opener

III I II

lap Hybrid-4

Waste removed. %

-

1.31.4 1.41.0 0.20.1 Lint, %

91.8 17.0

17.8 43.826.317.07.097.0 Seeds, %

-

6.93.9 0.33.3 7.8 4.0 Matwd f1brq;. %

-

11.512.0 9.0 21.433.037.5

Shirley ~ % 6.2

60.2 61.7 44.948.736.8 35.32.7*

~.~ ooOJposition*, % ^23.4

5;.048.6 43.558.939.490.5

coats 7B.2

10-361aesh'

26.028.0 9.3 23.524.938.3 39.6

;S;~~

d"

^21.0^21.4^19.8^16.0^52.8'^23.3 ^ItA

*OveralIcleaning efficieo..-y ofB.K.., 56.S-/.

0.2

4.7 97.8

7.7

35.3

SO.8 1.2*

30.1 78.1

45.9 22.8

s.ria

Waste removed, %

-

1.21.2

B B

0.1 Lint, %

93.9 12.5

YILl

Y

9.3 P

P

Seeds, %

0.4 14.24.4

A 14.6A Matted fibres, %

-

18.38.4S

S

32.2 Shirley trash, %

61.8S62.0 3.7

S

43.3 E

E Shirley

trash

com-D D

position, % ^{Seed coats}

51.9 19.3

-

30.7

-

34.4 10-36 mesh

29.3 57.6

-

50.2

-

40.2

>36 mesh

22.819.2 17.4

- -

15.0

*Overall cleaning efficiency of B.R., 70.7%

GUPTA et al.: CLEANING AT BLOW ROOM &CARDS IN RELATION TO NATURE OF TRASH: PART I

spectively based on the data in Table 2 were chosen. to extract more waste at blow room. In the case of The cottons were processed on the same blow room Suvin, the expected cleaning efficiency at 2.7%

line in the sequence shown by the column headings waste would be only about 46%. Even after allowing from left to right in Table 4. for greater efficiency due to the presence of whole Since the total trash in Suvin was only 4.1% ,Seeds, the observed efficiency is higher. This higher compared to 6.2% in Hybrid~4, the two porcupipe, ob~rved cleaning efficiency for Suvin supports the openers were bypassed while processing S\lvin hypoth~is that the cottons contl,lining a lower . cotton. The results in Table 4 show that the overall Pt(J~ttiotl of seed coats are easier to clean in the cleaning efficiency of the blow room line isabQut. blQw'room.than those containing more seed coats.

57% for Hybrid-4 and 71% for Suvin witb'w~ie Hpwever, more experimentation would be nee- removal of 5.4% and 2.7% respectively. Accordit1g essary to draw .general conclusions ... , to ATlRA norms based on industry surveys '(1955- .Machine position and type oj cleaning at blow,

1960), the expected values of waste and:cle~ning room -The analysis of waste. samples (Table 3)had would be about 7% and 72% for HYbrj.d-4.and indicated preferenti$l removal of certain types of about 4.6% and 67% for Suvin. In the case of . trash;.-at some of the machines in the blow room.

Hybrid-4, the cleaning efficiency would be nearly' ..1'h4fiCSuld be two reasons "for this behaviour: (i) the same as the norms if the desired quantity of preferentiala£tion.Qf.a·Particular beater for a waste ^(7<'10) could be removed. This, however, was particular tyPe of tra~b; and (iiithe pOsition of the found to be difficult to achieve under the existing beater in the line.· To study which of these is conditions. It is likely that the nature of trash predominant, an .ejpe~t was conducted in (higher proportion of seed coats) makes it difficult which cotton from the hopper bale opener was fed

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INDIAN J. TEXT. RES, VOL. 3, JUNE 1978

Trash

Table 5 - Machine Posidoa aDd Cleaulag at Blow Room

analysis

Normal sequence Changed sequence Mix- Sup-

Stri-

Ver-Por-Two- Fini- Mix- Two- Sup-Stri- Por-Two- KiTS- Fini-

ing· ticalcu-sherercu-chner shererkerbla-ing·bla-kerbla- ^)'"~

(308) c1ea-

c1ea- pineope-

dedlap(308) dedbeater lapclea- c1ea- pineded ner

ner

neropen- bea- bea- nerneropen- bea-

er tertert terer

Wasteremoved,%

-

2.90.1_OJ^1.I

^-

1.1

-

0.40.20.22.50.21.8

Lint,% 20.818.322.996.840.597.513.921.594.111.215.017.38.78.9 90.1

Seeds,% 10.2^0.20.67.92.24.95.63.23.51.95.11.7

-

1.4

Matted fibres,% 22.111.911.4^0.14.433.011.88.816.814.86.45.6

-

0.1

Shirleytrash,% 69.174.356.146.469.669.672.557.45.045.570.865.92.82.2 7.5 Shirley trash composition

Seedcoats,%

36.3 54.7 22.140.5 24.150.2 78.662.0 40.824.4 25.951.9 62.757.272.7

10-36mesh,% 13.727.429.435.024.632.931.026.034.622.722.617.57.27.7 23.3

>36 mesh, % 23.429.228.516.040.051.049.120.516.512.924:314.38.69.0 22.4

i

Overallcleaningefficiency,68.5% Overallcleaningefficiency,57.7%

·The trash in the same mixingwas different before and after change of sequence. tThe waste sample of Kirschner beater whichfollowedwas lost and therefore data are not reported.

_-- _ i I

-- - -- -- : : I I

-,"-"._"_.I1"""""'II_I,lIl111i1l1lllllillllllli.iIII,"I"'"I,""I~IIII"''.""""II"'HIII.II",,,,,,",,,',,,,ji'~"!Iloll""II,,,a,I.I""I'"Il"I"'"I1II""",,li"'~~~I<iI"""II,II""llililli""'"''''''''"""""''''''_''"I''~II,1

I

waste is much higher (70 : 30) compared to that for licker-in I (30 : 70). The trash from the flat strips contains about 85% seed coats against the 80% fed in the lap, indicating preferential action of flats in removing seed coats compared to blow room and licker-in. But the lint to trash ratio is very high in flat waste (30 : 70), with the result that after taking lint into accouns the proportion of s;ed coats in

flat waste is only marginally higher than that in licker-in and blow room machine wastes.

Effect of licker-in andflat speeds- Experiments were conducted with different licker-in and flat speeds for the two cottons, Hybrid-4 and Suvin, to

Overall cleaning effiCiency, 78.6%

.Other than seed coats Licker-in I: Mote knives

region

Licker-in II: Licker-in fly

Table 6 - Proportion of Various Types of Trash in Card Waste and Sliver

Trash 30s Mixing

analysis

Licker- Licker- Flat Cyl.

Lap Sliver'.- m

wastein&

I II

Dof-

flyfer Waste, %

0.3 1.3

2.70.4 Lint, %

29.0 67.1

56.9 64.3 96.798.5 Shirley trash, %

65.5 21.0

38.3 24.52.8 0.6

Shiriey trash composition, %

42.9 39.2 84.5 29.877.3 77.1 Seed coats

35.1 26.7

10.2 45.37.7 20.5*

10-36 mesh

22.7 76.6

4.7 57.66.7 directly to the two-bladed beater (last machine In

the sequence) instead of the supercleaner (the first machine in the sequence). The Crighton opener was eliminated in the changed sequence to keep the .mber of cleaning points same. The results given in Table 5show that the drastic change in the beater poSition has not influenced the composition of trash in the waste to a considerable extent. Incidentally, the total trash content and also the proportion of whole seeds which are easy to remove in the blow room were substantially less for the mixing processed with the changed sequence. These two factors together may be responsible for the drop in the overall cleaning efficiency with the changed sequence, Since the composition of Shirley trash in mixings did not differ much in different trials, firm conclusions can be drawn about the action of cleaning points by comparing the composition of Shirley trash in wastes of the two sequences. In short, these results indicate that the type of cleaning action plays a more important role in determining the cleaning behaviour of a blow room machine than its position in the sequence.

Cleaning at Cards

Nature of trash in card waste -The analysis of waste samples (Table 6) from the major cleaning positions of the card shows that the trashes in licker- in I region (mote knives region) and licker-in II region (motes fly) contain only 40-45% seed coats despite the fact that the trash in the lap contained almost 80% seed coats. The cleaning in the licker-in region thus resembles that in the blow room. As expected, the lint to trash ratio for the licker-in II

34

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35 Data given in Tables 3-6 have been used to

calculate separately the cleaning efficiencies of blow room and cards for seed coats and other than seed coats (all meshes combined). The results given in Table 7 show that the cleaning efficiency of blow room is much higher for trash other than seed coats (about 83% against 50% for seed coats). The overall cleaning efficiency of the individual blow room lines has been calculated by taking the weighted average of the proportion of type of trash and the corresponding cleaning efficiency. For instance, for 30s mixing, the calculated blow room cleaning efficiencyis [(54.7.)( 50)

+

(45.3 x.83)jlOO=64.9., The calculated cleaning efficiency values for all the three blow room lines are very near the observed cleaning efficiency values. Thus, the overall cleaning efficiency of the conventional blow room (adjusted for the number of beating points, depending upon the total trash) may be predicted if the proportion of seed coats in the mixing is known.

In the case of cards, the average cleaning efficiency of both types of trash works out to 85%.

85.0 90.9

89.1

89.0

52.6

65.9 85.4

67.6

Cards Blow Room

86.9

86.7

57.2

86.8 49.7

81.0 56.5

76.7

78.6

79.1

~.9 46.3

82.3

62.7

Seed coats Other than seed coats

Overall (observed)

GUPTA et al.: CLEANING AT BLOW ROOM &CARDS IN RELATION TO NATURE OF TRASH: PART I

find out whether the proportion of seed coats in the Summary and Conclusions

sliver trash can be affected by such changes. Both Amethod is reported for the quantitative all31ysis these trials indicate that the effect of changes in of various types of trash. The nature and proportion licker-in or flat speeds on the nature of trash of different types of trash in several Indian cottonS removed at carding is marginal. were analysed and experiments were conducted at blow room and cards to understand the cleaning

... behaviour with reference to diffetent types oftrash.

C~eanlDgEffiCienCiesof Blow Room and Cards for The following conclusions have emerged from the

Different Types of Trash study.

(1) The largest single component (45-75% by wt) of trash in Indian cottons was the seed coats which are fuzzy seed fragments adhering tenaciously to clusters of fibres. Full seeds formed 5-25% of the total trash, while the proportion of clusters of matted fibres was negligible in most cottons.

(2) The present blow room machines have been found to be less effective in removing seed coats than the other kinds of impurities likest!e<ls, leafy matter, sand, etc. And since seed coats form the major constituent of trash in Indian cottons,· the cleaning efficiency at blow room is related to the proportion of seed coats in cotton/The cleaning efficiency was higher when the proportiQn of seed coats in cotton trash was low. The type of blow room machine appeared to have a greater influence on the nature of trash removed than its position in the sequence.

(3) Cleaning at the licker-in is similar to that in the blow room; but that between flats and cylinder is markedly different; the trash in flat waste contains about 85% seed coats against about ^4()Of.. at licker-in. Changes in licker-in and flat speed did not influence the manner of trash removal to an ap- Table 7 -Cleaoing Effidencies of BlowReom aod Cards preciable extent, though the overall trash in sliver

for Differeat Types of Trash was lower at the higher flat speed.

Acknowledgement

.' The authors thank the management and staff of 30s Hybnd-4 SUVIDAverage the Silver Cotton Mills and Jupiter Textile, .Mills 49 5 for pro~ding facilities for conducting blow room

. and card experiments. The trash analysis by the 82.9 newly evolved procedure was done by Shri R.

Bhagat.

Refereuees

1. Peirce, F.T., Kelly, J.F. & Coleman, M.H.,J. Text ..

Inst.,46 (1955), T78-144.

2. Bhaduri, S.N. & Purohit, J.N!, Cleaning>achieYed

and lint· lost in blow rDom and CflllTding,

ATiRA Research Note, 1957.

3. Subramanian, T .A.

&

Patel, S.M., ^..4TlJU.SilYer 85.0 .Jubilee MonogMplr (Ahmedabad Textile Industry's Research Association, Ahmc-

.A.ssuming 50% cleaning effICiencyfor seed coats and 4. A ~U,ye'Y:abad), 0'.f197B4;~ChapterI wW rfJOm4'n78..TractJUS SITRA

83% for other than seed coats. '

________________ Research Report, April 1960.

Seed coats Other than' seed coats

Overall (observed) Overall (calculated)·