THE EFFECT OF THE PHYSICAL PROPERTIES OF PARTICLES OF BULK-BLENDED FERTILIZERS ON SEGREGATION BY CONING

Silva, G.A. da

doi:10.1590/S0104-66321997000300011

Acessibilidade / Reportar erro

Brasil

Brazilian Journal of Chemical Engineering

Español English

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

• Braz. J. Chem. Eng. 14 (3) • Sept 1997 • https://doi.org/10.1590/S0104-66321997000300011 copy

THE EFFECT OF THE PHYSICAL PROPERTIES OF PARTICLES OF BULK-BLENDED FERTILIZERS ON SEGREGATION BY CONING

Bulk blending is a way to produce compound fertilizers in which the different nutrients are present in different particles. Due to the heterogeneous composition of bulk blends, particle segregation, when it occurs, is a serious problem to the fertilizer producer, as well as to the farmer. Free fall is one of the main types of particle movement to promote segregation. The physical properties of the particles that potentially affect the tendency to segregate the most are size, density and shape. The main objective of this work is to study the influence of size and density of particles and distance of fall on segregation due to free fall. It was found that particle size is the most important physical characteristic to affect segregation; the greater the difference in particle size, the greater the segregation. Free fall is an important mechanical factor affecting segregation; the greater the distance of fall, the greater the segregation. No evidence of the influence of particle density on segregation was found

Bulk-blended; compound fertilizers; segregation by coning

Brazilian Society of Chemical Engineering Rua Líbero Badaró, 152 , 11. and., 01008-903 São Paulo SP Brazil, Tel.: +55 11 3107-8747, Fax.: +55 11 3104-4649, Fax: +55 11 3104-4649 - São Paulo - SP - Brazil
E-mail: rgiudici@usp.br

Acompanhe os números deste periódico no seu leitor de RSS

Mixture no.	Component A		Component B		D_A/D_B	r_A/r_B
Mixture no.	D_A(mm)	r_A(g/cm3)	D_B(mm)	r_B(g/cm³)	D_A/D_B	r_A/r_B
I.1	2.87	1.94	1.30	1.94	2.21	1.00
I.2	2.87	1.94	1.84	1.94	1.56	1.00
I.3	1.84	1.94	1.30	1.94	1.42	1.00
I.4	2.87	1.61	1.30	1.61	2.21	1.00
I.5	2.87	1.61	1.84	1.61	1.56	1.00
I.6	1.84	1.61	1.30	1.61	1.42	1.00
I.7	2.87	1.43	1.30	1.43	2.21	1.00
I.8	2.87	1.43	1.84	1.43	1.56	1.00
I.9	1.84	1.43	1.30	1.43	1.42	1.00
II.1	2.87	1.94	2.87	1.43	1.00	1.36
II.2	2.87	1.94	2.87	1.61	1.00	1.20
II.3	2.87	1.61	2.87	1.43	1.00	1.13
II.4	1.84	1.94	1.84	1.43	1.00	1.36
II.5	1.84	1.94	1.84	1.61	1.00	1.20
II.6	1.84	1.61	1.84	1.43	1.00	1.13
II.7	1.30	1.94	1.30	1.43	1.00	1.36
II.8	1.30	1.94	1.30	1.61	1.00	1.20
II.9	1.30	1.61	1.30	1.43	1.00	1.13

Ang. seg.	Mass of components in the binary mixture (g)
	Run 1		Run 2		Run 3		Run 4		Run 5
	A	B	A	B	A	B	A	B	A	B
1	125.73	30.96	125.64	31.06	125.60	31.09	125.50	31.20	125.46	31.24
2	79.87	20.51	79.76	20.54	79.84	20.58	79.80	20.61	79.78	20.60
3	51.46	37.86	51.58	37.75	51.45	38.05	51.63	37.80	51.58	37.95
4	45.64	34.54	45.65	34.51	45.89	34.31	45.27	34.45	45.66	34.54
5	32.40	38.51	32.43	38.47	32.45	38.47	32.02	38.49	32.28	38.65
6	22.20	56.69	22.19	56.67	21.90	56.99	22.16	56.74	22.20	56.71
7	18.39	61.94	18.36	61.99	18.47	62.44	18.41	61.95	18.40	62.00
8	18.36	73.65	18.77	73.25	18.84	73.06	18.79	72.94	18.77	73.26
9	50.65	88.93	50.62	89.01	50.50	88.13	50.47	89.18	50.41	89.22

Test conditions			Run no.
material	R = D_A/D_B	h (cm)	1	2	3	4	5
KCl	2.21	50	0.4601	0.4590	0.4582	0.4587	0.4588
MAP			0.4612	0.4613	0.4625	0.4596	0.4588
DAP			0.4567	0.4576	0.4594	0.4588	0.4591
KCl	1.56	50	0.4082	0.4090	0.4077	0.4075	0.4069
MAP			0.4069	0.3670	0.4064	0.4075	0.4108
DAP			0.4078	0.4074	0.4086	0.4071	0.4078
KCl	1.42	50	0.3583	0.3599	0.3593	0.3579	0.3572
MAP			0.3587	0.3573	0.3559	0.3585	0.3580
DAP			0.3587	0.3576	0.3598	0.3577	0.3582
KCl	2.21	30	0.3269	0.3275	0.3248	0.3275	0.3239
MAP			0.3242	0.3258	0.3243	0.3256	0.3251
DAP			0.3252	0.3254	0.3265	0.3269	0.3272
KCl	1.56	30	0.2828	0.2916	0.2910	0.2909	0.2901
MAP			0.2887	0.2893	0.2905	0.2908	0.2906
DAP			0.2889	0.2837	0.2876	0.2890	0.2904
KCl	1.42	30	0.2504	0.2498	0.2517	0.2521	0.2524
MAP			0.2525	0.2524	0.2543	0.2522	0.2517
DAP			0.2513	0.2523	0.2532	0.2513	0.2524

Test conditions			Run no.
Part. size (mm)	r = r_A/r_B	h (cm)	1	2	3	4	5
2.87	1.36	50	0.0099	0.0091	0.0100	0.0100	0.0100
1.85			0.0076	0.0075	0.0092	0.0076	0.0081
1.30			0.0078	0.0075	0.0072	0.0075	0.0077
2.87	1.20	50	0.0094	0.0094	0.0094	0.0093	0.0094
1.85			0.0071	0.0072	0.0073	0.0072	0.0072
1.30			0.0075	0.0074	0.0076	0.0076	0.0073
2.87	1.13	50	0.0098	0.0099	0.0101	0.0100	0.0100
1.85			0.0081	0.0080	0.0080	0.0080	0.0080
1.30			0.0071	0.0069	0.0070	0.0072	0.0072
2.87	1.36	30	0.0095	0.0096	0.0095	0.0095	0.0095
1.85			0.0071	0.0069	0.0071	0.0070	0.0070
1.30			0.0057	0.0062	0.0060	0.0061	0.0062
2.87	1.20	30	0.0094	0.0085	0.0095	0.0095	0.0096
1.85			0.0065	0.0065	0.0065	0.0065	0.0064
1.30			0.0075	0.0077	0.0077	0.0075	0.0075
2.87	1.13	30	0.0094	0.0092	0.0091	0.0088	0.0091
1.85			0.0062	0.0062	0.0062	0.0062	0.0062
1.30			0.0057	0.0057	0.0057	0.0059	0.0053

Source of variation	Freedom degrees	Sum of squares (x10³)	Average squares (x10³)	F
Distance of fall (h)	1	316.26	316.26	14,335
Particle size (D)	2	114.89	57.45	2,604
Density (r)	2	0.02	0.01	0.53
Interaction h x D	2	2.92	1.46	66.07
Interaction h x r	2	0.02	0.01	0.42
Interaction D x r	4	0.05	0.01	0.53
Interaction h x D x r	4	0.12	0.03	1.31
Residue	72	1.59	0.02	1.00
Total	89	435.86

Source of variation	Freedom degrees	Sum of squares (x10⁴)	Average squares (x10³)	F
Distance of fall (h)	1	6.46	6.46	1.109
Particle size (D)	2	8.23	4.12	0.707
Density (r)	2	8.60	4.30	0.736
Interaction h x D	2	9.51	4.76	0.817
Interaction h x r	2	8.06	4.03	0.692
Interaction D x r	4	27.71	6.93	1,190
Interaction h x D x r	4	26.53	6.63	1,140
Residue	72	419.01	5.82	1,000
Total	89	514.11