Effect of biowaste and construction waste additives on mechanical dewaterability of lake sediment for brick production

Figures & data

Table 1. Sample analytical methods.

No	Parameters	Unit	Analytical methods
1	Moisture content	%	TCVN 4196:2012
2	pH	–	TCVN 4192:2011
3	Composition (Sand, limon and clay) (Sand, limon and clay)	%	TCVN 6862:2012
4	Al2O3	%	TCVN 7891:2008
5	Fe2O3	%	TCVN 7891:2008
6	SiO2	%	TCVN 7891:2008
7	CaO	%	TCVN 7891:2008
8	MgO	%	TCVN 7890:2008
9	Cl^-	%	TCVN 6194-1-1996
10	SO4^2-	%	TCVN 6200:1996
11	As	mg/kg	TCVN 8467:2010 (ISO 20,280:2007)
12	Cu	mg/kg	TCVN 6496:2009 (ISO 11,047:1998)
13	Zn	mg/kg	TCVN 6496:2009 (ISO 11,047:1998)
14	Cr	mg/kg	TCVN 6496:2009 (ISO 11,047:1998)
15	Cd	mg/kg	TCVN 6496:2009 (ISO 11,047:1998)
16	Pb	mg/kg	TCVN 6496:2009 (ISO 11,047:1998)
17	Total organic matters	%	TCVN 7376:2004
18	Heat value	kCal/kg	ASTM D240
19	Coliforms	MPN/100 ml	TCVN 6187–1:2019
20	E. Coli	MPN/100 ml	TCVN 6187–1:2019
21	TSS	mg/L	TCVN 6625:2000
22	TN	mg/L	TCVN 6638:2000
23	NH4^+-N	mg/L	TCVN 6179–1:1996
24	COD	mg/L	SMEWW 5220C:2017
25	As	mg/L	SMEWW 3113B:2017
26	Zn	mg/L	SMEWW 3120B:2017
27	Pb	mg/L	SMEWW 3120B:2017
28	Cr	mg/L	SMEWW 3500-Cr.B:2017

TCVN: Vietnam national technical standards, ASTM: American Society for Testing and Materials; SMEWW: Standard Methods for the Examination of Water and Wastewater; TSS: Total Suspended Solids; COD: Chemical Oxygen Demand; TN: Total Nitrogen.

Figure 1. Image of testing Additives: (a) rice husk powder_RHP; (b) corn core powder_CCP; (c) peanut shell powder_PSP; (d) sugarcane bagasse powder_SBP; (e) autoclaved aerated concrete_AAC and (f) stone powder_SP.

Figure 2. Mechanical dewatering procedure in the lab.

Table 2. Characteristic of DSL sludge’s sediment.

No	Parameters	Unit	Average value	QCVN 43:2017/BTNMT
1	Moisture content	%	62.20	–
2	pH	–	7.32	–
3	Compositions			–
4	- Sand	%	45.70	–
5	- Limon	%	32.50	–
6	- Clay	%	21.80	–
7	Al2O3	%	4.12	–
8	SiO2	%	41.50	–
9	CaO	%	6.25	–
10	Fe2O3	%	3.14	–
11	K2O	%	2.37	–
12	MgO	%	1.19	–
13	MnO	%	0.08	–
14	SO4^2-	%	1.20	–
15	Cd	mg/Kg	<2.00	3.50
16	As	mg/Kg	36.20	17.00
17	Co	mg/Kg	250.80	–
18	Cr	mg/Kg	210.20	90.00
19	Cu	mg/Kg	95.70	197.00
20	Pb	mg/kg	97.30	91.30
21	Zn	mg/kg	750.70	315
22	Total organic matters	%	20.60	–
23	Heat value	kCal/kg	1800	–

QCVN 43:2017/BTNMT: National technical regulation on sediment quality.

Table 3. Characteristic of DSL sludge’s supernatant.

Parameters	Unit	Average Value	QCVN 14:2008/BTNMT, column B
pH	–	7.31	5.5–9
TSS	mg/L	171.5	100
VSS	mg/L	84.9	N/A
COD	mg/L	275	150
TN	mg/L	33	40
N-NH4^+	mg/L	11	10
Total Coliform	MPN/100 ml	39000	5000
E. Coli	MPN/100 ml	4490	N/A
As	mg/L	<2.10^−3	0.1
Cd	mg/L	4.10^−3	0.1
Cr	mg/L	2.10^−3	0.1
Pb	mg/L	2.10^−3	0.5

QCVN 14:2008/BTNMT: National Technical Standard for domestic wastewater effluent; TSS: total suspended solids; VSS: volatile suspended solids; COD: chemical oxygen demand; TN: total nitrogen.

Figure 3. Organic matters in the DSL with and without additives (DSS: dredged sludge from sewers; CCP: corn core powder, RHP: rice husk powder, SBP: sugarcane bagasse powder, and PSP: peanut shell powders; AAC: autoclaved aerated concrete and SP: stone powder).

Figure 4. Correlation of organic matter (OM) and heat value.

Figure 5. Energy supplement with different mixing sludge: raw material ratio.

Figure 6. Moisture contents of testing DSL with mixing ratio: (A) 1:3, (B) 1:5 and (C) 1:7 (DSS: dredged sludge from sewers; CCP: corn core powder, RHP: rice husk powder, SBP: sugarcane bagasse powder, and PSP: peanut shell powders; AAC: autoclaved aerated concrete and SP: stone powder).

Figure 7. SEM images (magnification of 1000X) of raw and blended dredged sludge from lake. DSL: Dredged sludge from lake (A), DSL + AAC: autoclaved aerated concrete 1:7 (B); DSL + SP: stone powder 1:3 (C) and DSL + PSP: peanut shell powders 1:7 (D).

Figure 8. Acceptable mixing ratio for DSL in terms of oxides (red line: the standard values for corresponding oxide contents in the brick).

Table 4. Chemical characteristics of samples.

No	Index	Unit	M1	M2	M3	Standard
1	Al2O3	%	4.12	8.35	9.14	–
2	CaO	%	6.25	21.65	8.37	–
3	Fe2O3	%	3.14	2.87	5.02	–
4	K2O	%	2.37	1.02	1.52	–
5	MgO	%	1.19	2.92	1.24	–
6	MnO	%	0.08	0.06	0.09	–
7	P2O5	%	0.78	0.69	1.07	–
8	TiO2	%	0.33	0.45	0.51	–
9	SiO2	%	81.74	61.99	73.04	–
10	Ag	mg/Kg	<2	<2	<2	–
11	As	mg/Kg	36.20	33.30	39.90	17
12	B	mg/Kg	35.70	40.10	45.10	–
13	Ba	mg/Kg	420.50	420.50	450.00	–
14	Be	mg/Kg	<5	<5	<5	–
15	Bi	mg/Kg	<10	<10	<10	–
16	Cd	mg/Kg	<2	<2	<2	3.5
17	Ce	mg/Kg	52.40	40.10	59.40	–
18	Co	mg/Kg	250.80	92.50	106.70	–
19	Cr	mg/Kg	210.20	45.70	140.20	90
20	Cu	mg/Kg	95.70	98.20	126.30	197
21	Ga	mg/Kg	<10	<10	<10	–
22	Ge	mg/Kg	<20	<20	<20	–
23	La	mg/Kg	24.60	23.30	29.10	–
24	Li	mg/Kg	30.20	22.30	36.10	–
25	Mo	mg/Kg	<5	<5	<5	–
26	Nb	mg/Kg	6.20	5.80	9.40	–
27	Ni	mg/Kg	84.50	18.30	54.40	–
28	Pb	mg/Kg	97.30	77.50	83.50	91.3
29	Sb	mg/Kg	20.80	<10	<10	–
30	Sc	mg/Kg	7.20	<5	7.10	–
31	Sn	mg/Kg	<10	<10	<10	–
32	Sr	mg/Kg	250.50	290.50	137.00	–
33	Ta	mg/Kg	<10	<10	<10	–
34	V	mg/Kg	72.10	38.90	69.50	–
35	W	mg/Kg	45.30	<20	35.40	–
36	Y	mg/Kg	15.00	12.50	19.20	–
37	Zn	mg/Kg	750.70	710.20	902.80	315

M1: raw DLS, M2: DLS + SP; M3: DLS + AAC. Standard: QCVN 43:2017/BTNMT – National technical regulation in sediment quality. Bold values are those under the standard values.

“-“: Not applicable.

Table 5. Correlation matrix.

	Type of additives	Mixing ratio	After mixing	After compression
Type of additives	1.00
Mixing ratio	0.21	1.00
After mixing	0.12	0.58	1.00
After compression	−0.47	0.19	0.36	1.00

Table 6. Two-way ANOVA results (p value, n = 36) showing the impact on moisture content by different additives and mixing ratio, based on Turkey Kramer approach.

		After mixing	After compression
General interaction
	Type of additives (A)	0.01	0.00
	Mixing ratio (B)	0.02	0.09
	A x B	0.94	0.01
Detailed interaction according to Tukey-Kramer method
Type of additives (A)	Mixing ratio (B)
Sugarcane bagasse	(1) vs (2)	0.46	0.00
	(1) vs (3)	0.03	0.00
	(2) vs (3)	0.18	0.78
Peanut shell	(1) vs (2)	0.03	0.02
	(1) vs (3)	0.02	0.01
	(2) vs (3)	0.99	0.42
Corn core	(1) vs (2)	0.09	0.95
	(1) vs (3)	0.03	0.99
	(2) vs (3)	0.81	0.96
Rice husk	(1) vs (2)	0.88	0.00
	(1) vs (3)	0.58	0.16
	(2) vs (3)	0.85	0.00
Stone powder	(1) vs (2)	0.27	0.00
	(1) vs (3)	0.70	0.00
	(2) vs (3)	0.71	0.55
AAC powder	(1) vs (2)	0.99	0.47
	(1) vs (3)	0.29	0.03
	(2) vs (3)	0.37	0.24

Mixing ratio 1:3 (1); 1:5 (2) and 1:7 (3), p < 0.05: significant impact.

Data availability statement

The data that support the findings of this study are available from the corresponding author, upon reasonable request.