Pig slurry management for agricultural use

Transcription

1 Symposium no. 15 Paper no Presentation: poster Pig slurry management for agricultural use DELGADO M. del Mar, PORCEL Miguel Angel, MIRALLES DE IMPERIAL Rosario, BELTRÁN Eulalia M., MARTÍN José Valero and BERINGOLA Luisa Department of Environment, INIA Apdo 8111 Madrid, Spain Abstract The liquid waste in lagoons contains high concentrations of nutrients and salts and, in many cases, is applied to farmland as fertilizer. The study was conducted at the National Institute for Agricultural Research in Madrid and the objective of this research was to evaluate the level of evaporation and the evolution of ammonium, nitrate, total nitrogen Kjeldahl and Chemical Oxygen Demand (COD) in animal waste, using an evaporation system. Finally, mean concentration obtained in this test (2,4 g/m 3 in COD, 171 g/ m 3 in Total nitrogen Kjeldahl, 114 g/m 3 in NH + 4-N and 4 g/m 3 in NO - 3N) confirmed the possibility of using this evaporation process in order to be able to apply pig slurry as fertilizer. Keywords: fertilization, evaporation, ammonium, nitrate, pig slurry, Chemical Oxygen Demand Introduction The hod breeding sector in our country estimates the annual production of pig slurry around 25 million of TM. This huge development makes necessary study of the environment impact of this compound. The pig slurry has certain characteristics that make it a better recycled organic fertilizer than others (Delgado et al., 1999). It is mainly an organic residue, its application improve soil structure and soil microbiology activity, but the main advantage is its high value in nutrients, especially in nitrogen and potassium. However, it shows some disadvantages: the difficult manage due to its volume (94% of water), contaminant effects due to its content in heavy metals and sodium (Diez et al., 1999, Ham et al., 1998). The recycling of pig slurry as a natural fertilizer is an important alternative in countries such as our (Smith and Chambers 1993). Spain has a Mediterranean climatology an arid and semiarid character and soils with a low content in organic matter (Delgado et al., 1999). The purpose of present study was to determinate the evolution of ammonium, nitrate, total nitrogen Kjeldahl and Chemical Oxygen Demand using a evaporation system. Material and Methods The study was conducted at the National Institute for Agricultural Research in Madrid, Spain. The system consists of two lagoons with 35 m 3 (lagoons 1) and 75 m 3 (lagoons 2) of capacity and filled with pig slurry from farm located in the centre of Spain

2 17 th WCSS, August 22, Thailand Pig slurry samples were taken from three different sites in the lagoon every fifteen days for nine months. The analytical procedure was: Chemical Oxygen Demand (COD) was determined by Potassium Dichromate method, where the excess of dichromate was treated with Mohr Salt and the amount of organic matter must be proportional to dichromate consumed. The ammonium nitrogen and nitrate nitrogen in the water samples were analyzed by distillation and total nitrogen Kjeldahl was determined by Kjeldahl method (APHA-AWWA-WPCF, 1992). Results and Discussion Figure 1 shows the cumulative evaporation of pig slurry in lagoons versus time and it can see that in lagoon 2 the evaporation is greater than lagoon 1, because the pig slurry of lagoon 2 came from the lagoon 1 and it has more solids on its surface due to it directly receives pig slurry from the farms. 1 EVAPORATION 9 8 Evaporation (cm) /1/99 3/11/99 3/12/99 3/1/ 29/2/ 3/4/ 3/5/ 3/6/ 3/7/ Figure 1 Evaporation of pig slurry (cm) in lagoons versus time (days) Figures 2, 3, 4 and 5 represent the concentration evolution (g/m 3 ) of COD, KN, NH 4 + -N, NO 3 - -N in the lagoons versus time (days). The results show that maximum percentage reduction of Chemical Oxygen Demand (Figure 2) was obtained during the month of December with 6% for lagoon 1 and 5% for lagoon 2. In that way, from an initial concentration of 5964 g/m 3 in lagoon 1 and 4374 g/m 3 in lagoon 2 it was reduced to 24 g/m 3 and 216 g/m 3 respectively. During March it was achieved the average value for stabilization total Kjeldahl nitrogen. Initial concentrations in lagoon 1 and 2 (14 g/m 3 and 696 g/m 3 ) have been

3 17 th WCSS, August 22, Thailand shown in Figure 3 and the final concentrations were 171 g/m 3 and 134 g/m 3 with 88% and 81% reduction respectively. 7 CHEMICAL OXYGEN DEMAND 6 5 COD (g/m 3 ) /1/99 28/1/99 6/1/ 2/1/ 3/2/ 17/2/ 2/3/ 16/3/ 13/4/ 27/4/ 11/5/ 25/5/ 8/6/ Figure 2 Chemical Oxygen Demand (g/m 3 ) versus time (days). 16 KJELDAHL NITROGEN K-N (g/m 3 ) /1/99 28/1/99 6/1/ 2/1/ 3/2/ Figure 3 Total nitrogen Kjeldahl (g/m 3 ) versus time (days). 17/2/ 2/3/ 16/3/ 13/4/ 27/4/ 11/5/ 25/5/ 8/6/

4 17 th WCSS, August 22, Thailand 9 AMMONIUM NITROGEN 8 7 NH4-N (g/m3) /1/99 28/1/99 6/1/ 2/1/ 3/2/ 17/2/ Figure 4 Ammonium nitrogen (g/m 3 ) versus time (days). 2/3/ 16/3/ 13/4/ 27/4/ 11/5/ 25/5/ 8/6/ 2 NITRATE NITROGEN NO3 - -N(g/m 3 ) /1/99 28/1/99 6/1/ 2/1/ 3/2/ Figure 5 Nitrate nitrogen (g/m 3 ) versus time (days). 17/2/ 2/3/ 16/3/ 13/4/ 27/4/ 11/5/ 25/5/ 8/6/

5 17 th WCSS, August 22, Thailand For the ammonium nitrogen the initial concentrations were: 817 g/m 3 (lagoon 1) and 595 g/m 3 (lagoon 2) and it maintained constant in April month with average values of 114 g/m 3 (lagoon 1) and 53 g/m 3 (lagoon 2) and reductions of 86% and 91% respectively (Figure 4). Finally, maximum reduction of nitrate nitrogen was in April with 94% in lagoon 1 and 93% in lagoon 2, during the month of December data were stabilized (Figure 5). References APHA-AWWA-WPCF Standard methods for the examination of water and wastewater. American Public Health Association, New York. 874 p. Bocchi, S. and Tano F Effects of cattle manure and components of pig slurry on maize growth and production. European Journal of Agronomy 3: Delgado, M Nitrogen mineralization from residues organic. International Journal of Environmental Pollution. Delgado, M. et al Depuración de purines de cerdo para su reutilización. Rev. Mundo Ganadero Año X. Nº. 117: Diez, J., A. Tarquis, A. Vallejo, M. Cartagena and L. Sanchez Effect of application of pig slurry on soil pollution and nitrate lixiviation. Soil and Environment: Water and plant quality Ham, J.M., L. Reddi, C.W. Rice and J.P. Murphy Evaluation of lagoons for the containment of animal waste. Kansas Center for Agric. Resources and the Environmental Kansas State University, Manhattan. 152 p. Huffman, R.L. and P.W.Westerman Estimated seepage losses from established swine waste lagoons in the lower coastal plains of north Carolina. Trans of the ASAE. 38: Smith, K.A. and B.J. Chambers Utilizing the nitrogen content of organic manures on farms. Problems and practical solutions. Soil, Use and Management. 9: