Using of water treatment sludge from frozen seafood factory for vegetable production

Transcription

1 Symposium no. 2 Paper no. 23 Presentation: poster Using of water treatment sludge from frozen seafood factory for vegetable production KHEMTHONG M. (1), SUNGPETCH A. (1), ARUNLERTAREE C. (1), NAVANUGRAHA C. (1), PHAVAPHUTANON L. (2), WONGMANEEROJ A. (2) and CHANPRAME S. (2) (1) Faculty of Environmental and Resource Studies, Mahidol University, Bangkok, Thailand (2) Faculty of Agriculture, Kasetsart University, Bangkok, Thailand Abstract Sludge from the wastewater treatment of frozen seafood factory (The Union Frozen Products Co., Ltd.) is used to substitute chemical fertilizer ( ) for vegetable production. Growth responses of water convolvulus (Ipomoea aguatica), green kuang futsoi (Brassica chinensis), Chinese kale (Brassica alboglabra) and lettuce (Lactuca sativa) to different rates of dry sludge were investigated. Sludge at the rates of 3.75, 7.5, and t ha -1 for each treatment and chemical fertilizer ( ) at the rate of 3.75 t ha -1 was incorporated into Kamphaeng Saen Soil Series (Typic Haplustalfs, fsi, mixed). From this study, the dry sludge from this factory demonstrated the main properties as follows: ph 5.25, CEC meq/1 mg, organic matter 26.35%, total nitrogen 13.73%, available phosphorus mg kg -1, and soluble potassium.87 mg kg -1. The results of plant production showed that the dry sludge provided higher vegetative growth rate of plants than the chemical fertilizer. Dry sludge at the rate of t ha -1 gave the best yield of water convolvulus and green kuang futsoi i.e., 1.68 and 6.5 g/plant, respectively, whereas, the rate of 7.5 t ha -1 gave the best yield of chinese kale and the rate of 3.75 t ha -1 gave the best yield of lettuce i.e., 2.6 and 5.12 g/plant, respectively. Moreover, it can increase macronutrient and also organic matter in soil. From the study results it can be concluded that this sludge can be used as the organic fertilizer for leafy vegetable production. Keywords: chemical fertilizer, dry sludge, frozen seafood factory, vegetable production Introduction The most efficient methods of treating wastewater from frozen seafood processing is the use of bacteria to eliminate organic matter in the sewage based on an aerobic reaction. The process begins with natural oxidation ponds up to the sequencing batch reactor system (SBR) which requires high investment and is suitable for a limited area. The treatment is optimal when oxygen is not less then.5 mg L -1, BOD: N: P equal to 1: 5: 1, ph 6-9 and maximum temperature of o C (Irvine and Ketchum, 1998). All water treatment methods resulted in sludge production which varies in components according to methods of the production processes of each factory. According to Engineering-Science Co., Ltd. the amount of sludge generated in 1986 and 21 were 3,7 and 21,53 tons, respectively (The National Council of Environment, 23-1

2 17 th WCSS, 1-21 August 22, Thailand 1988). As the problem of sludge management is on the rise in various industrialized cities, an alternative way to solve this problem is to maximize the use of the sludge by developing it as animal feed, soil amendment or fertilizer. The idea of using it as animal feed has been adopted by the Japanese who has successfully produced animal feed out of sludge from frozen seafood processing factories. The feed consists of 9% nitrogen,.7% phosphorus, 1% potassium and 56% protein from fish (Tisdale and Nelson, 1975). For the idea of using as soil amendment or fertilizer, it has also been adopted to produce planting substrate fertilizer out of sludge from various type of factories, since major components i.e., nitrogen and potassium are useful to plants. This study involves the reuse of sludge from seafood processing factories as fertilizer for leafy vegetable production. In addition, the study includes property and composition analysis of sludge. The result of which will be applied to plant anatomy and production in order to recommend the appropriate level of sludge that would be most beneficial for the plants. The wash abilities and accumulation of toxic substance in sludge, and both in surface water and in different parts of plants were also monitored. This is to ensure that using of uncontaminated sludge will serve as an alternative way to reduce soil and water pollution problems by using sludge as fertilizer. Materials and Methods Analysis of sludge and soil properties Sludge from frozen seafood factory was air-dried and then its chemical properties were determined using methods stated in Table 1. Field soil using in this study was Kamphaeng Saen Soil Series. It was also analyzed in the same manners as sludge before and after planting. Table 1 Sample analysis methods used in this experiment. Parameters Unit Sample Method of analysis ph - Dry sludge, soil ph meter CEC meq/1g Dry sludge, soil 1 N NH OAc,1 N NH Cl,1% NH - oxalate, NH OH did, titration Organic matter % Dry sludge, soil Wet Oxidation Organic carbon % Dry sludge, soil Wet Oxidation C/N ratio - Dry sludge, soil %OC/Total N Total N mg kg -1 Dry sludge, soil, plant Kjeldahl method Total P mg kg -1 Plant Conc.HClO titration, Vanado molybdic acid method Total K mg kg -1 Plant Conc.HClO titration,aas Bray II Available P mg kg -1 Dry sludge, soil 1 N NH OAC, AAs Available K mg kg -1 Dry sludge, soil Conc.HNO 3 digestion, AAs Ca mg kg -1 Dry sludge, soil,plant Conc.HNO 3 digestion, AAs Mg mg kg -1 Dry sludge, soil,plant Conc.HNO 3 digestion, AAs Cu mg kg -1 Dry sludge, soil,plant Conc.HNO 3 digestion, AAs Fe mg kg -1 Dry sludge, soil,plant Conc.HNO 3 digestion, AAs Mn mg kg -1 Dry sludge, soil,plant Conc.HNO 3 digestion, AAs Zn mg kg -1 Dry sludge, soil,plant Conc.HNO 3 digestion, AAs 23-2

3 17 th WCSS, 1-21 August 22, Thailand Planting, growth measurements, and plant nutritional analysis According to RCBD experimental design, 12 sub-plots of 1 x 2 m each were prepared under the 16 meshes per inch nylon net house for each plant species. The four plant species in the this experiment and planting space were: water convolvulus (Ipomoea aguatica), 1 x 1 cm; Green kuang futsoi (Brassica chinensis), 15 x 15 cm; Chinese kale (Brassica alboglabra), 15 x 15 cm. and lettuce (Lactuca sativa), 2 x 2 cm. The treatments comprised of T 1 = Kamphaeng Saen Soil Series. (KPSs) + chemical fertilizer ( ) 3.75 t ha -1, T 2 = KPSs t ha -1 dry sludge, T 3 = KPSs t ha -1 dry sludge and T = KPSs t ha -1 dry sludge. Fertilizer or sludge were mixed thoroughly into the plot prior to planting. Growth parameters including leaf size, leaf number and stem height were examined every week. At the harvesting date, plants were harvested from the area of.5 x.5 m in the middle of each sub-plot and were dried down at 7 C for 8 h using hot air oven. After measuring of plant dry weight, dry samples were and then were finely ground using grinding mill. The total N, P and K in each sample were further determined using methods stated in Table 1. The analysis of variance (ANOVA) and Duncan s new multiple range test (DMRT) procedures were used to analyze the data. Results and Discussion The properties of soil before planting Kamphaeng Saen Series Soil texture was silty clay loam, which consisted of sand, silt, and clay in the amount of 2%, 55%, and 3%, respectively. The chemical analysis (Table 2) indicated that soil ph was also neutral with moderately high CEC (cation exchange capacity) of meq/1 mg. The CEC related to the fairly high amounts of clay and organic matters in the soil. This soil contained small amount of clay resulting in both low available P and low exchangeable K. The C/N ratio was found to be at a suitable ratio of.71. These allowed microorganisms to degrade organic matters quite well without using NH + and NO 3 in the soil. The amount of calcium and magnesium were presented at low to levels, which was not likely to cause a significant problem. The properties of dry sludge The ph of dry sludge (Table 2) was acidic (ph=5.25) due to seawater and brackish water used in production process of frozen seafood factories (Jacobs, 1981). The CEC of meq/1 mg was very high as a result of the dry sludge containing up to 26.35% of organic matters. High CEC indicated better absorption of nutrients in the form of cation (+). The C/N ratio of 1.12 indicated the instantly degradable organic matters that and caused no immobilization of inorganic N (Alexander, 1967). An amount of nitrogen was up to 13.73%, which was considered to be suitable for growing leafy plants. The quantities of available P and K were and.87 mg kg -1, respectively. The other micronutrients were also in sufficient amount for the growth of plants (Bockmand et al., 199). The quantities of some heavy metal such as copper, iron, manganese, and zinc in the dry sludge were.2, , 152.8, and mg kg -1, respectively. 23-3

4 17 th WCSS, 1-21 August 22, Thailand The properties of soil mixture The results of soil mixture analysis of treatments prior to planting were illustrated in Table 2. The ph values of all treatments were within the neutral range. The higher CEC was found in the soil + dry sludge mixtures than in the soil + chemical fertilizer mixture. It was noticeable that the more dry sludge applied, the more soil organic matters and the more micronutrients found. Effect of dry sludge on the changes in soil properties after harvesting was obvious that, with an addition of dry sludge, the soil gained more organic matters and also became more neutral. Table 2 The properties of soil (KPS), dry sludge, mixture of soil and chemical fertilizer ( ), and mixture of soil and dry sludge in various treatments. Parameter KPSs Dry T1 T2 T3 T sludge B A B A B A B A ph 7.29 a 5.25 b 7.99 a a / a a 7.21 CEC ab c d abe be - cde b %OM 2.8 a b 2.9 a a a a 3.3 %OC 1.65 a b 1.5 a a a a 1.95 C/N.71 a 1.12 b 2.79 b -.23 a -.57 a -.19 a - ratio %Total.35 a ab.52 b.3 a.35 c.38a.35 d.37 a.3 abcd.5 b N Avail. P Sol. K ns acd b bc d d c Ca ns* a c b b b Mn 9.2 ac c bc bc ac b Cu 1.5 ac.2 abc 1.22 a.99 a 1.36 c 1.33 c 1.93 c 1.8 c 2.85 a 1.76 c Fe 8.22 acd d b bcd b bcd 15.2 b 28.8 abc 17.9 b bcd Mg a a a a b 3.2 a c a ac bc Zn 39.5 ac bc ab 5.98 ab c c b 72.6 c b 8.3 c T1 = Kamphaeng Saen Soil Series (KPSs) + chemical fertilizer ( ) 3.75 t ha -1 T2 = KPSs + dry sludge 3.75 t ha -1 T3 = KPSs + dry sludge 7.5 t ha -1 T = KPSs + dry sludge t ha -1 ns = non significant ns* = non significant in the analysis before planting only *abcde = different alphabets in the same row mean significantly different at 95% confidential level. B = before planting, A = after planting. Effects of dry sludge on plant growth An appropriate quantity of dry sludge used varied according to plant species (Figures 1- and Table 3). The result showed that the utilization of dry sludge in Kamphaeng Saen Soil Series enhanced plant growth and gave earlier harvesting with more plant yields than that of chemical fertilizer ( ). From the results, it could be stated that dry sludge from frozen seafood factory at the range of t ha -1 can be used in substitution of chemical fertilizer ( ) for leafy vegetable production. 23-

5 17 th WCSS, 1-21 August 22, Thailand Table 3 The dry weight of plants from treaetments using chemical fertilizer ( ) or dry sludge from frozen seafood factory. Plant Species Dry weight (g/plant) T1 T2 T3 T Water convolvulus 1.16 a 1.61 b 1.6 b 1.68 b Green kuang futsoi 3.1 a.61 b.1 b 6.5 c Chinese kale ns Lettuce 3.7 ab 5.12 c.63 b.73 c T1 = Kamphaeng Saen Soil Series (KPSs) + chemical fertilizer ( ) 3.75 t ha -1 T2 = KPSs + dry sludge 3.75 t ha -1 T3 = KPSs + dry sludge 7.5 t ha -1 T = KPSs + dry sludge ton/ha ns = non significant *abc = different alphabets in the same row mean significantly different at 95% confidential level. leaf size (cm 2 ) number of leaves height of stem (cm.) Figure 1 Leaf size, leaf number and stem height of water convolvulus (Ipomoea aguatica). 23-5

6 17 th WCSS, 1-21 August 22, Thailand leaf size (cm 2 ) W eek1 W eek2 W eek3 number of leaves height of stem (cm) Figure 2 Leaf size, leaf number and stem height of green kuang futsoi (Brassica chinensis). T1 = Kam Phaeng Saen Soil Series(KPSs) + chemical feritilizer ( ) 3.75 t ha -1 T2 = KPSs + dry sludge 3.75 t ha -1 T3 = KPSs + dry sludge 7.5 t ha -1 T = KPSs + dry sludge t ha -1 leaf size (cm 2 ) Week 1 1 Week 2 2 Week Week 3 3 Week Week 8 number of leaves 6 2 Week 2 height of stem (cm.) Week Figure 3 Leaf size, leaf number and stem height of Chinese kale (Brassica alboglabra) (Lactuca sativa)brassica alboglabra. 23-6

7 17 th WCSS, 1-21 August 22, Thailand 25 2 leaf size (cm 2 ) Week 16 number of leaves 12 8 Week 1 1 Week 22 Week 3 3 Week Figure The leaf size and leaf number of lettuce (Lactuca sativa). T1 = Kam Phaeng Saen Soil Series(KPSs) + chemical feritilizer ( ) 3.75 t ha -1 T2 = KPSs + dry sludge 3.75 t ha -1 T3 = KPSs + dry sludge 7.5 t ha -1 T = KPSs + dry sludge t ha -1 Plant nutritional analysis The plant nutritional analysis of four plant species demonstrated the higher value of N, P, K and some minor elements as showed in Table and 5. Table The effects of dry sludge or chemical fertilizer ( ) on tissue mineral concentration of water convolvulus and green kuang futsoi. Water convolvulus green kuang futsoi T1 T2 T3 T T1 T2 T3 T %Total N %Total P %Total K % Ca Mn (mg kg -1 ) Cu (mg kg -1 ) Fe (mg kg -1 ) Mg (mg kg -1 ) Zn (mg kg -1 ) T1 = Kamphaeng Saen Soil Series (KPSs) + chemical fertilizer ( ) 3.75 t ha -1 T2 = KPSs + dry sludge 3.75 t ha -1 T3 = KPSs + dry sludge 7.5 t ha

8 17 th WCSS, 1-21 August 22, Thailand Table 5 The effects of dry sludge or chemical fertilizer ( ) on tissue mineral. concentrations of Chinese kale and lettuce. Chinese kale lettuce T1 T2 T3 T T1 T2 T3 T %Total N %Total P %Total K % Ca Mn (mg kg -1 ) Cu (mg kg -1 ) Fe (mg kg -1 ) Mg (mg kg -1 ) Zn (mg kg -1 ) T1 = Kamphaeng Saen Soil Series (KPSs) + chemical fertilizer ( ) 3.75 t ha -1 T2 = KPSs + dry sludge 3.75 t ha -1 T3 = KPSs + dry sludge 7.5 t ha -1 T = KPSs + dry sludge t ha -1 Conclusion The sludge from wastewater treatment of frozen seafood factory contained macroand micro-nutrients in the appropriate amount for chemical fertilizer replacement in leafy vegetable production. The N-P-K of only sludge tested was13.73% mg kg -1 and.87 mg kg -1, respectively. Tested in Kamphaeng Saen Soil Series, the optimal rate for producing water convolvulus and green kuang futsoi was t ha -1. The appropriate rates for production of Chinese kale and lettuce were 7.5 and 3.75 t ha -1, respectively. The analysis of all plant species tested demonstrated the higher value of N, P, K and some minor elements in plant tissue. For the soil properties, it was obvious that, with an addition of dry sludge, the soil gained more organic matters and became more neutral than the soil in treatments without sludge added. Acknowledgement The authors would like to acknowledge the National Science and Technology Development Agency, Ministry of Science Technology and Environment, Thailand, for the founded through the project of The development of frozen seafood industrial sludge reused in crop production. References Alexander, M Introduction to Soil Microbiology. John Wiley and Sons Inc, New York. Bockman, O.C., O. Kaarstad, O.H. Lie and I. Richards Agriculture and fertilizers. Agricultural Group, Tangen Grafiske Senter, Norsk Hydro a.s., Norway. Irvine, R.L. and L.H. Ketchum Jr Sequencing batch reactor for biological wastewater treatment. CRC Crit. Rev. Environ. Control. 18: 255. Jacobs, L.W Agricultural application of sewage sludge. Sludge and its ultimate disposal. Department of Crop and Soil Science, East Lansing, Michigan. The National Council of Environment, Thailand Nation Hazardous Waste Management Plan. Tisdale, S.L. and W.L. Nelson oil fertility and fertilizers. 3 rd ed. Macmillan Publishing Co. Inc., New York. 23-8