Indian Journal of Chemical Technology Vol. 9, July 2002, pp. 306-311

Articles

Vermicomposting of paper waste with the anecic earthworm Lampito mauritii Kinberg

S GajaJakshmi, E V Ramasamy & S A Abbasi*

Centre for Pollution Control and Energy Technology, Pondicherry University, Kalapet, Pondicherry 605 014, India

Received 27 June 200J ; revised received 5 March 2002; accepted JO April 2002

Long term performance of 'vermireactors' in which paper waste was converted to vermicasts by the anecic earthworm Lampito mauritii Kinberg has been assessed. The study is focussed on four aspects: (a) recovery of vermicasts in digesters fed with paper blended with cowdung in 4:1, 5:1, and 6:1 ratios (by weight), (b) reproduction/mortality of earthworms in the reactors, (c) growth of earthworms in terms of increase in zoomass, and (d) the effect of digester volume on the three aforementioned factors. These studies are a sequel to the work reported earlie~ where four species of epigeic and anecic earthworms were screened for their efficiency and sustainability in processing waste paper. The studies had indicated L mauritii and Eudrilus eugeniae Kinberg to be the most efficient producers of vermicasts, with L mauritii a shade above E. eugeniae. As L mauritii is an indigenous species whereas E.eugeniae is an exotic in the Indian context, it seems that the former may adapt better ecologically, hence is more resilient, than the latter.

Used and torn or shredded paper ensuing from small offices and households forms a substantial fraction of municipal solid waste (MSW) in India1

•2

. In several institutions, paper waste is burnt off leading to air pollution and unseemly sights of ash heaps. Apart from this, such practices entail wastage of organic carbon which might be put to good use3

. The situation in other third-world countries is no different4

, and may perhaps be existing elsewhere too.

Earthworms ingest soil and various forms of biomass to produce castings. Baring a few exceptions the castings of most earthworm species are known to contain harmones and enzymes which stimulate plant growth and discourage pathogens. In several, though not all, cases the castings also contain plant nutrients nitrogen, phosphorus, and potassium (NPK) in a more plant-available form than the parent matter. Lastly, the castings are believed to be good 'soil conditioners' as they improve water retention and facilitate establishment of plant roots. For all these reasons vermicasts are favoured by farmers all over the world, and find a ready market.

An extensive program of studies has been taken up to develop basic and applied knowledge for using earthworms in processing paper waste. In an earlier sequence of six-month long trials, four species of

*For correspondence: (E-mail: proCabbasi@vsnl.com; Fax: 0413-655227)

earthworms-including two epigeics EudriLus eugeniae Kinberg and Perionyx excavatus Perrier, and two anecics Drawida willsi Michaelsen and Lampito mauritii Kinberg were screened for their efficiency and sustainability in producing castings from feed consisting of 6: 1 (by weight) blends of paper waste and cowdung. The trials revealed that L. mauritii and E. eugeniae each produced significantly more castings per unit feed and per unit reactor volume than D. wilLsi or P. excavatus. Thus, it was decided to subject L. mauritii to further detailed investigation vis-a-vis vermiconversion of paper waste. Besides being the most efficient producer of vermicasts amongst the four species tested, L. mauritii has the added advantage of being indigenous to India5

•6 and is

widely distributed, especially in the Southern region7.

On the other hand, E. eugeniae is an exotic speciesB

and is likely to be less resilient than L. mauritii. Further, L. mauritii was also found to be more reproductive than the other two indigenous species D. willsi and P. excavatus. This attribute would further enhance the efficiency of vermireactors run on L. mauritii.

Study on the recovery of vermicasts in digesters fed with paper blended with cowdung in 4: 1,5: 1, and 6: I ratios (by weight), reproduction/mortality of earthworms, growth of earthworms in terms of increase in zoomass in the reactors and the effect of digester volume on three aforesaid factors has been reported here.

Indian J. Chern. Techno\., May 2002 Articles

Table 14-dAB values of EGOS & EGMS

Name of ester Alcohol-water, A 0 Dioxane-water, A 0 OM SO-water, A 0 DMF-water, A 0

EGOS 4.2-9.6 2.1-3.0 0.8-1.0 0.1-0.3

EGMS 2.5 1.5 0.2 0.03

EGOS: Ethylene glycol distearate, EGMS : Ethylene glycol monostearate

If the anion desolvation mechanism were operative this would imply decreasing size of the nucleophile with increasing dioxane/DMSOI DMF content in the solvent medium. Such a charge in the steric bulk of the attacking reagent should be reflecting by the variation in the reaction constant parameter O. However, such responses are not generally recorded in 0 at higher mole fractions of dioxane/DMSO/DMF.

It is also obvious that systems which involve a high degree of internal stabilization of the transition state are susceptible to pronounced dipolar aprotic solvent influences. Further, on the basis of this observation, it would be seen that one can use di-polar aprotic solvent influences on reaction rates as a criterion in the assessment of anchimeric assistance in reactions involving internally stabilized transition states.

Acknowledgements The authors are grateful to the authorities of V.R.

College of Engineering, Nagpur for providing necessary laboratory facilities to carry-out this work. The authors also wish to express their sincere gratitude to Dr V. Ramchandra Rao, retired Prof. and Head, Dept. of Chemistry, VRCE for his encouragement in the progress of this work. One of the authors (K. Gajanan) is grateful to the Management, Dr. G. Thimma Reddy, Principal and Dr. K. Vijaya Mohan, Head Dept. of Chemistry, KITS, Ramtek for their kind permission and constant encouragement during this work and also to Sqn.Ldr. K. R. Sharma and other family members for their forbearance and continued moral support.

References 1 Swain C G, J Alii Che1l1 Soc, 66 (1944) 1696. 2 Anantkri shnan S V & Venkatratnam R V, Indiall J Chem, 4

(1966) 379. 3 Anantkrishnan S V & Venkatratnam R V, Proc Indian Acad

Sci, Sec A 65 (1967) 188. 4 Bruice Thomas C & Thomas Fife, JAm Chem Soc, 84 (1962)

1973. 5 Rao G V & Venkatasubramanian N, Indian J Che1l1 , 10

(1972) 178. 6 Balakrishnan M, Rao G V &Venkatasubramanian N, J Chem

Soc Perkin Trans, 2 (1974) 6. 7 Holba V, Benko & Komadel P Z, Phys Che1l1 (Leip zig), 262

(1981) 445. 8 Singh 0 P, Prasad & Sunil Kumar, J Indian Chem Soc,

67(2), (1990) 114. 9 Niyaz M & Arifin, J Colloid Interface Soc, 180(1) (1996)

132. 10 Wheeler, Graham & Cock-Croft W E, Educ Chem, 34(2)

(1997) 47 . II Ghosh Kallol K & Thakur Santhosh S, Indian J Che1l1 Soc,

76(1) (1999) 15. 12 Ghosh Kallol K & Kishore K, Indian J Chem, Sec B, 38

B(3) (1999) 337. 13 Yu He, Zhang & Juxian, Huaxe Yanji Yu Ying Yang, 12(2)

(2000) 234. 14 Zhan Chang, Guo Landry, Bonald W & Rick L, J Phys

Chem, 104(32) (2000) 7672. 15 Shi Ji-Liang, Xu Jia-yi, Yi Hu-Non & Xi-kui, Chin J Che1l1,

18(4) (2000) 617. 16 Kumuira C K, Murai Koichi & Hidetoshi y, Kogya Keguka

Zasshi, 71 (9) (1968) 1569. 17 Parker A J, Chem Revs, 69 (1981) 1. 18 Haberfield P, Friedman J & Pinkston M F, JAm Chem Soc,

94 (1972) 71. 19 Ingold C K, Structure and Mechanism in Organic Chemistry

(Cornell University Press, Ithaca, New York), 1953,345. 20 Benson S W, The Foundation of Chemical Kinetics

(McGraw-Hill Book Co Inc, New York), 1960,535 .

21 Tommila E & Murto M L, Acta Chem Seand, 17 (1963) 1947.

305

Gaja\akshmi et al.: Vermicomposting of paper waste with anecic earthworm Articles

Experimental Procedure

Vermireactors

The vermireactors consisted of circular plastic containers, volume 4 or 12 L, dia 24 or 46 cm, depth 9 or 30 cm. These were filled from bottom up with successive layers of sawdust, river sand, and soil of depths 1,2, and 4 cm respectively. In each reactor, 20 healthy, adult individuals of L. mauritii were introduced. These animals were randomly picked from the cultures maintained by the authors with cowdung as the feed . Each culture had more than 200 animals from where 20 individuals were randomly picked for these experiments. The reactor bed was kept at - 50% moisture by periodic sprinkling of adequate quantities of water. The reactor feed consisted of pieces of paper (as they occurred in the waste taken from trash bins), after they were soaked in water for a week, squeezed, and mixed with cowdung. All quantities were adjusted so that the feed mass reported in this paper represents dry weights (taken after oven-drying at 105°C to constant weight).

The castings contained soil particles besides vermidigested organic matter. In order to estimate the mass of this entrained soil, a portion of the castings was ovendried at 105°C to constant weight, thoroughly mixed with a known quantity of water, and kept for a while. The castings floated to the top while the soil particles settled at the bottom. The castings and the underlying water was separated from the soil by first decantation of the castings and the bulk of the liquid, and then filtering off the rest. The castings and the liquid were ovendried to constant weight. The soil was separately ovendried to a constant weight. This enabled us to determine the mass fraction of soil particles contained in the castings each time. This fraction was subtracted from the total mass of castings recovered each time. Thus, the vermiconversion data presented here pertains to conversion of only the feed to the castings, and excludes the entrained soil.

All reactors were operated under identical settings of temperature and ambient humidity. Duplicates were run for all studies and were started with 75 g of feed. Three types of feed were studied, comprising paper waste : cowdung in mass ratios of 4 : 1, 5 : 1, and 6 : 1. For each feed type six reactors were operated. Of these two reactors, each of 3 L volume, were run with L. mauritii population maintained at its original 20 animals by periodically removing the offsprings from the digesters. Of the other four reactors, two were of 3 L capacity and two of 12 L.

These were run in the same manner as the two reactors described above, but without removal of offsprings. In all cases the number of offsprings generated during each fortnightly run were recorded.

Results and Discussion Table 1 presents fortnightly recovery of vermicasts,

in terms of percentage of feed mass, from all the reactors over seven months. To provide an indication for the reproducibility of the recovery data, the findings of the duplicate Reactors I & II are given for each of the three feed types studied. It may be seen that in one case (first run, 5 : 1 :: paper: cowdung feed), the recovery in the duplicates disagreed to the extent of 13%. In three other instances (fifth and eleventh runs, 4 : 1 :: paper: cowdung feed, and eleventh run, 6 : 1 :: paper : cowdung feed), the duplicates disagreed to the extent of 7-9%. In all other instances the duplicates were in closer agreement which, considering the heterogeneous nature of the reactor contents, may be deemed very good. For the sake of brevity, only the averages of the duplicates are given for other reactors in Table 1.

The trends of vermicast recovery as a function of the age of the reactor followed a consistent pattern in case of all the 18 reactors (Fig. 1). There was a slow but steady rise in vermiconversion from the beginning uptil the fifth run. Thereafter, a plateau was reached and was maintained for over four-and-a-half months. This indicates that the earthworms, which had been raised in cowdung-fed reactors before they were transferred to the experimental reactors, took time to adapt to the paper-rich feed and, after the initial lag phase, have achieved a consistent rate of vermicast output. The fact that identical plateaux have occurred in reactors where earthworm population was controlled to the initial number, as well as in reactors where no such control was exercised, indicates that the contribution of juveniles in utilization of feed has not reached perceptible levels in the latter type of reactors. It is expected that as the juveniles approach adulthood they would begin consuming substantial mass of the feed, thereby pushing the vermicast output above the plateau. This may continue till the death of the 'parent' worms may cause a temporary lowering of output.

Table 1 also reveals that the overall average vermicast recovery in digesters contammg increasingly higher fraction of paper is not significantly different from each other. Further, vermiconversion in digesters of 12 L volume

307

w o 00

Runs (each of 15 Reactor

days) I

2

3

4

5

6

7

8

9

10

11

12

13

14

Aver­age

45.9

42.6

49.5

54.1

56.7

59.3

61.1

62.4

60.5

58.5

57.2

55.9

56.9

55.9

Table I-Recovery of vennicasts (%) as a function of time

4: 1: : paper: cowdung

Reactor Aver-Reactors Reactors Reactor II age III & IV V & VI I

average average

44.8 45.4 42.7 51.2 38.4

49.7 46.1 53.3 58.5 43.8

52.5 51.0 55.0 60.0 50.5

61.0 57.6 58.0 59.5 52.0

64.5 60.6 60.5 63.6 56.0

61.3 60.3 57.1 62.3 55.3

61.9 61.5 58.0 59.8 57.1

60.3 61.4 59.3 62.4 55.9

61.5 61.0 59.9 62.8 58.1

61.6 60.1 58.9 59.2 54.9

60.2 58.7 60.3 62.5 53.4

57.7 56.8 60.9 62.7 56.2

54.1 55.5 57.6 59.0 57.5

58.9 57.4 62.4 60.1 54.3

56.7 57.4 60.3

5:1 : : paper: cowdung

Reactor A ver- Reactors Reactors Reactor II ~ m&N V&~ I

average average

51.2 44.8 42.7 51.2 42.7

42.6 43.2 45.0 47.4 47.4

47.5 49.0 48.8 54.0 50.8

54.5 53.3 53.5 58.0 49.5

56.7 56.4 55.6 61.0 53.0

57.3 56.3 56.7 58.8 54.0

57.5 57.3 56.9 59.0 58.5

58.4 57.2 57.2 57.9 59.9

" 57.1 57.6 59.1 58.5 57.2

56.4 55.7 54.9 58.8 57.7

60.2 56.8 "56.5 60.1 58.9

54.7 55.5 57.5 58.9 57.6

57.2 57.4 60.8 61.6 58.9

57.0 55.7 61.1 57.6 58.4

54.0 54.7 57.3

6: 1: : paper: cowdung

Reactor A ver- Reactors Reactors II age III & IV V & VI

average average

40.5 41.6 38.4 36.8

51.5 49.5 52.1 54.5

52.2 51.5 53.5 56.0

52.0 50.8 50.5 57.5

57.1 55.1 55.9 62.5

57.1 55.6 55 .5 57.2

55.9 57.2 56.2 56.1

57.1 58.5 54.9 58.0

60.2 58.7 60.3 62.5

56.0 56.9 56.2 55.8

52.3 55.6 57.0 62.4

57.0 57.3 57.7 58.9

57.1 58.0 61.6 60.3

54.1 56.3 62.4 65.0

54.5 55.16 57.4

> ., .... r;. -~ rIJ

;-0-j;;" :: '-

(j :r (1)

? ~ (')

:r :: £. '­c -< IV o S

Gajalakshmi et al.: Vermicomposting of paper waste with anecic earthworm Articles

#. ~

! II:

it ~

I a::

70

60

50

40

30

20

10

0

70

60

50

40

30

20

10

0

0 1 2 3 .. 5 6 7 8 9 10 11 12 13 14 Fortnights

b

~ D 0 • t: • ~ t~

o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Fortnights

ro c

:F·~·4><! i:

10

2 3 4 5 e 7 8 9 10 11 12 13 14 Fortnights

Fig. I-Recovery of vermicasts (% of feed mass) with the feeds (a) paper : cowdung :: 4: I (b) paper:cowdung :: 5: I (c) paper : cowdung :: 6:1 -0- Controlled population, 3L -e- Uncontrolled population, 3L -/1- Uncontrolled population, 12L

4:1 5:1 6:1

Fig. 3-Net increase in earthworm zoomass _ Controlled population, 3L 0 Uncontrolled population, 3L _ Uncontrolled population, 12L

50 .------------------------------------,

40

~ 40

I! 35 a fi 30

j ~: ~ 15 > 10

o 0

50

45

~ 40

I! 35 q

I 30

20

15 20

~ 15

~ 10

6

0

50

45

~ 40 I! 35 Q

J 30

25

20

I 15

10

5 0

2 3 4 5 6 7 8 9 10 1 9 12 13 14 15

Fortnights

Fig. 2-Worm zoomass increase in seven months (a) paper:cowdung ::4 : I (b) paper:cowdung :: 5 : I (c) paper : cowdung :: 6 : I -0- Controlled population, 3L -e- Uncontrolled population, 3 L -/1- Uncontrolled population, 12 L

(Reactors V & VI) is only about 4-5% more than in 3 L digesters (Reactors I - IV). It follows that (a) 6 : 1:: paper: cowdung blends are nearly as acceptable to L. mauritii as 'blends with higher proportion of cowdung, and (b) a 4-fold increase in reactor volume does not significantly enhance the earthworm activity vis-a-vis production of vermicasts. The number of juveniles produced in the various reactors was close to 20 (Table 2) and no pattern can be discerned to say that reduction in the cowdung fraction of the feed, or an increase in reactor volume, facilitated reproduction of earthworms.

The mass of 'parent' worms increased almost linearly with time and grew by over 3-fold during the 7-month operation in all the reactors (Fig. 2). As it was revealed by Fig. 3, no trend can be discerned in this aspect too, to positively correlate increase in

309

w -o

Table 2-Number of earthworms found in the reactors each fortnight

Runs 4:1: : paper: cowdung 5:1 : : paper : cowdung 6: 1: : paper : cowdung

(each of Reactor Reactor 15 days) I II

Initial

2

3

4

5

6

7

8

9

10

11

12

13

14

Net increase

20 20

20 20

20 20

20 20

20 20+1

20+1 20+2

20+2 20

20+1 20+2

20+3 20+3

20+2 20+1

20+3 20+5

20+2 20+3

20+3 20+1

20+2 20+2

20 20+1

19 21

Aver- Reactors Reactors Reactor Reactor age III & IV V & VI I II

average average

20 20 20 20 20

20 20 20 20 20

20 20 20 20 20

20 20+2 20+1 20 20+1

20.5 20+2 20+2 20+2 20

21.5 20+5 20+5 20 20+4

21 20+5 20+8 20+3 20

21.5 20+8 20+10 20+3 20+2

23 20+9 20.16 20 20+3

21.5 20+13 20.17 20+1 20+2

24 20+13 20.19 20+4 20

22.5 20+15 20.19 20+2 20+5

22 20+16 20+19 20+1 20+4

22 20+18 20+20 20+2 20+1

20.5 20+19 20+20 20+2 20

20 19 20 20 22

Aver­age

20

20

20

20.5

21

22

21.5

22.5

21.5

21.5

22.0

23.5

22.5

21.5

21

20

Reactors Reactors Reactor Reactor III & IV V & VI I II average average

20 20 20 20

20 20 20 20

20 20 20 20

20+1 20 20+3 20+3

20+2 20+1 20+1 20+2

20+5 20+7 20 20+1

20+6 20+8 20+3 20

20+9 20+9 20+1 20+4

20+9 20+10 20 20+1

20+12 20+13 20+3 20+1

20+15 20+14 20+3 20+2

20+17 20+16 20+1 20+2

20+19 20+18 20+2 20+1

20+21 20+19 20 20+2

20+22 20+19 20+2 20+1

22 19 19 20

Aver­age

20

20

20

23

21.5

20.5

21.5

22.5

20.5

22

22.5

21.5

21.5

21.0

21.5

19.5

Reactors Reactors III & IV V & VI average average

20 20

20 20

20 20

20+4 20+3

20+6 20+6

20+8 20+6

20+9 20+8

20+9 20+10

20+12 20+10

20+13 20+13

20+15 20+14

20+16 20+17

20+18 20+19

20+19 20+21

20+21 20+22

21 22

> .., .... _. ~ -~ >rl

== 0-~ .

== '-

(") :r C1>

? ~ :r == 2. '-:. '< N

§

Gajalakshmi et al.: Vermicomposting of paper waste with anecic earthworm Articles

zoomass with paper/cowdung fractions in the feed, presence/absence of juveniles, or digester volume.

The studies reveal that a 6 : 1 : : paper : cowdung feed in 3 L digesters, each operated with 20 adult individuals of L. mauritii results in as good and as sustainable vermicast recovery as the more nutrient­rich feeds, and more spacious digesters employed in the present investigation.

Earlier Butt9 has explored the possibility of using paper mill sludge as a feed for the lob worm Lumbricus terrestris, and Elvira et al. 3 have found that addition of Eisenia andrei to paper mill sludge speeds up the process of hydrolysis and stabilization of the sludge. Both these reports emphasize that unless the sludges are augmented with a nitrogen-rich additive, the worms do not grow well or survive for long. Rosato and Elvira et at. 11,12 have also explored possibilities of using earthworms to hasten the stabilization of sludges coming from paper mill wastewater treatment systems. These studies indicate that the sludge stabilization is helped by the presence of earthworms and addition of sewage sludge, pig manure, or poultry droppings leads to higher rate of earthworm growth. But in all situations there is significant and persistent earthworm mortality.

A more recent study by Ceccanti and Masciandro l3

has reached similar conclusions. Recently published reviews l4

,15 indicate that studies of the type described in this paper emphasising on the utilization of paper waste via vermicomposting, have not been reported so far.

Acknowledgement The authors thank the All India Council for

Technical Education, Government of India, New Delhi, for financial support.

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Pollution Control (Orient Longman, Universities Press India Ltd., Hyderabad), 1999, 168.

2 Gajalakshmi S, Ramasamy E V & Abbasi S A, Environ Technol, 22 (2001) 679.

3 Elvira C, Dominguez J, Sampedro L & Mato S, Biocycle, 36 (1995) 62 .

4 Abbasi S A & Ramasamy E V, Solid Waste Management with Earthworms (Discovery Publishing House, New Delhi), 2001,178.

5 Ashok Kumar C, State of the Art Report on Vermiculture in India (Council for Advancement of Peoples Action and Rural Technology (CAPART), New Delhi), 1994,60.

6 Senapati B K, Proc of the Biogas Slurry Utilisation (Consortium on Rural Technology (CORT), New Delhi),1993,57.

7 Ismail S A, Ramakrishnan C & Angar M M, Proc Indian Acad Sci, (Anim Sci) , 99 (1990) 73.

8 Reinecke A J & Viljoen S A, Euro J Soil Bioi, 29 (I) (1993) 29.

9 Butt K R, Bioresource Technol, 44 (1993) 105. 10 Rosa Jean, Papel, 55 (6) (1994) 22. II Elvira C, Goicoechea M, Sampedro L, Mato S & Nogales R,

Bioresource Technol, 57(2) (1996) 173. 12 Elvira C, Sampedro L & Dominguez J, Soil Bioi Biochem, 29

(1997)759. 13 Ceccanti B & Masciandro G, Biocycle, 40 (1999) 71. 14 Ismail S A, The contribution of soil fauna especially the earth­

worms to soil fertility, Institute of Research in ~oil Biology and Biotechnology, The New College, Chennai (1998).

15 Szezeck M M, J Phytopathol-Phytopathologische Zeitschrift, 47 (1999) 155.

311