Study of PCDD/Fs distribution in fly ash, ash deposits, and bottom ash from a medical waste incinerator in China

Figures & data

Table 1. PCDD/Fs concentration in fly ash and bottom ash of BH-1 series

	[PCDDs], ng/g	[PCDFs], ng/g	[PCDF]/[PCDD]		TEQ-Conc. B ng I-TEQ/g	Ratios A/B
BH-1-1	155	870	5.16	1026	13.5	76.0
AirPreh-1-2	440	1652	3.65	2093	25.5	82.1
BH-1-3	561	1635	2.93	2196	25.5	86.1
BH-1-4	373	1265	3.36	1638	17.5	94.6
BH-1-5	71.8	368	4.89	440	6.90	64.8
BH-1-6	993	2807	2.89	3800	44.7	85.0
BH-1-7	452	1935	4.28	2388	67.3	35.5
BH-1-8	142	724	5.10	866	13.1	66.1
Slag-1-9	0.12	0.17	1.40	0.29	1.33 × 10^−3	218

Figure 1.  Distribution diagram of toxic PCDD/F concentrations in BH-1 ashes: (a) TEQ concentration; (b) mass percentage of total concentration.

Figure 2. Concentration distribution of toxic PCDD/Fs of (a) ash deposits, (b) bottom ash, and (c) flue gas.

Table 2. Average contents of major components and PCDD/F concentrations in flue gas

	H2O, %	CO2, %	O2, %	CO,mg/Nm^3	SO2,mg/Nm^3	NOx, mg/Nm^3	HCl, mg/Nm^3	[PCDDs],ng/Nm^3	[PCDFs],ng/Nm^3	[PCDF]/[PCDD]	PCDD/Fs,ng/Nm^3	TEQ-Conc., ng-ITEQ/Nm^3
F1	10.9	4.75	11.4	115	224	99.7	217.1	15.36	68.15	4.44	83.51	10.72
F2	6.85	4.99	11.8	127	340	135	175.0	3.87	12.82	3.31	16.69	2.19
F3	6.40	3.61	13.7	33.2	641	137	102.9	4.11	14.49	3.53	18.60	2.55
F4	11.4	0.39	18.7	244	174	26.8	232.0	2.13	6.93	3.26	9.06	0.92

Figure 3. Comparison of toxic PCDD/Fs distribution in cluster fly ash: A, B, and C are fly ashes from a MSWI (Kim et al., 2005), and WTE1 and WTE2 are fly ashes from chlorinated organic reagents and waste appliance incineration (Hagberg et al., 2005).

Figure 4. The scatter gram of load (TEQ and Total represent TEQ concentration and total concentration of PCDD/Fs, respectively, and BET is specific surface area).

Table 3. Correlation coefficient between PCDD/Fs and other physical and chemical parameters in fly ash

	TEQ	Total	BET	C	S	Cl	Ca	Fe	pH
TEQ	1	0.998	−0.119	0.039	−0.146	0.421	−0.120	0.290	−0.241
		(0.000)	(0.713)	(0.903)	(0.652)	(0.173)	(0.709)	(0.360)	(0.451)
Total	0.998	1	−0.140	0.022	−0.140	0.421	−0.103	0.294	−0.226
	(0.000)		(0.665)	(0.945)	(0.664)	(0.173)	(0.749)	(0.354)	(0.480)
BET	−0.119	−0.140	1	0.965	−0.365	−0.339	−0.568	−0.411	−0.551
	(0.713)	(0.665)		(0.000)	(0.244)	(0.280)	(0.054)	(0.184)	(0.063)
C	0.039	0.022	0.965	1	−0.442	−0.287	–0.581	−0.380	–0.596
	(0.903)	(0.945)	(0.000)		(0.150)	(0.365)	(0.047)	(0.224)	(0.041)
S	−0.146	−0.140	−0.365	−0.442	1	0.089	0.171	0.233	0.362
	(0.652)	(0.664)	(0.244)	(0.150)		(0.783)	(0.594)	(0.466)	(0.247)
Cl	0.421	0.421	−0.339	−0.287	0.089	1	−0.126	0.493	−0.445
	(0.173)	(0.173)	(0.280)	(0.365)	(0.783)		(0.696)	(0.103)	(0.147)
Ca	−0.120	−0.103	−0.568	–0.581	0.171	−0.126	1	−0.437	0.766
	(0.709)	(0.749)	(0.054)	(0.047)	(0.594)	(0.696)		(0.155)	(0.004)
Fe	0.290	0.294	−0.411	−0.380	0.233	0.493	−0.437	1	−0.276
	(0.360)	(0.354)	(0.184)	(0.224)	(0.466)	(0.103)	(0.155)		(0.385)
pH	−0.241	−0.226	−0.551	–0.596	0.362	−0.445	0.766	−0.276	1
	(0.451)	(0.480)	(0.063)	(0.041)	(0.247)	(0.147)	(0.004)	(0.385)
Notes: Total is the total concentration of PCDD/Fs^. BET is specific surface area. C, S, Cl, Ca, and Fe are carbon, sulfur, chlorine, calcium, and iron contents in fly ash. The boldface in the table highlights the maximum coefficient of the column data.