The application of leak detection and repair program in VOCs control in China’s petroleum refineries

Figures & data

Table 1. Basic information of four refineries.

Refinery	A	B	C	D
Site	Northwest China	Northeast China	Northwest China	Northeast China
Year	2010	1976	1992	1984
Refinery type	Fuel type	Fuel type	Fuel type	Fuel-lubricant type
Processing capacity (10^4 tons/year)	300 ~ 400	400 ~ 500	400 ~ 500	> 2000
Number of main processing units	13	16	14	37
LDAR program implementation year	2016	2016	2016	2017
Products	Gasoline, diesel, aviation kerosene, liquefied gas, propylene, sulfur, etc.	Gasoline, diesel, aviation kerosene, liquefied gas, propane, methyl ethyl ketone, benzene, etc.	Gasoline, diesel, aviation kerosene, liquefied gas, propylene, sulfur, petroleum benzene, road asphalt, etc.	Gasoline, diesel, kerosene, lubricating oils and paraffin, benzene, polypropylene, etc.

Table 2. Equipment leak rate for petroleum equipment components.

Equipment Component Type (All Services)	e0 (kg/hr/source)	ep (kg/hr/source)	ef (kg/hr/source)
Pump	2.4E-05	0.16	5.03E-05× SV^0.610
Compressor	4.0E-06	0.11	1.36E-05× SV^0.589
Agitator	4.0E-06	0.11	1.36E-05× SV^0.589
Valve	7.8E-06	0.14	2.29E-06× SV^0.746
Pressure relief device	4.0E-06	0.11	1.36E-05× SV^0.589
Open-ended line	2.0E-06	0.079	2.20E-06× SV^0.704
Flange	3.1E-07	0.084	4.61E-06× SV^0.703
Non-flanged connector	7.5E-06	0.030	1.53E-06× SV^0.735
Others	4.0E-06	0.11	1.36E-05× SV^0.589

Note: kg/hr/source = kilograms TOC per hour per source

Table 3. Numbers of equipment components in different refineries.

Refinery	A	B	C	D
Pump	361	469	299	1859
Valve	25,210	21,782	24,061	126,797
Flange	50,387	39,970	46,262	239,998
Open-ended line	3015	3421	4552	20,156
Non-flanged connector	96,471	77,206	83,649	519,568
Compressor	3	0	1	41
Agitator	20	0	9	444
Pressure relief device	138	11	1	29
Sampling connection system	0	0	0	0
Total	175,605	142,859	158,834	908,892

Figure 1. Distribution of equipment components in different refineries.

Table 4. Numbers of leaking components in different refineries.

Refinery	Pump	Valve	Flange	Open-ended line	Non-flanged connector	Total
A	3	158	212	140	229	742
B	1	214	175	68	87	545
C	1	118	86	151	42	398
D	4	428	521	457	330	1740

Note: the compressors, agitators, pressure relief devices and sampling connection system are not listed since the concentrations of these components are below the leak definition concentrations.

Figure 2. Distribution of leaking components in different refineries.

Figure 3. Distribution of high leaking components in total leaking components in different refineries.

Table 5. VOC emissions from all equipment components (unit: tons/year).

Refinery	A	B	C	D
Pump	0.73	1.32	0.23	1.1
Valve	33.52	103.86	39.27	166.44
Flange	18.52	34.93	12.34	111.16
Open-ended line	16.46	26.28	44.66	125.94
Non-flanged connector	14.38	12.64	7.43	51.64
Compressor	0	0	0	0
Agitator	0	0	0	0.04
Pressure relief device	0.03	0	0	0
Sampling connection system	0	0	0	0
Total	83.64	179.04	103.93	456.32

Figure 4. Distribution of VOC emissions from all equipment components.

Table 6. VOC emissions from leaking components (unit: tons/year).

Refinery	Pump	Valve	Flange	Open-ended line	Non-flanged connector	Total
A	0.31	31.07	13.93	16.17	8.99	70.47
B	0.22	89.61	23.20	19.95	6.51	139.49
C	0.05	37.54	10.84	44.42	2.61	95.45
D	0.41	105.14	82.43	108.87	12.28	309.13

Figure 5. Distribution of VOC emissions from leaking components.

Table 7. Different proportion of VOC emissions.

Refinery	Percentage of VOC emissions from leaking components in total VOC emissions from all components (%)	Percentage of VOC emissions from high leaking components in total VOC emissions from all components (%)	Percentage of VOC emissions from high leaking components in VOC emissions from leaking components (%)
A	84.3	78.5	93.1
B	77.9	76.3	97.9
C	91.8	89.8	97.8
D	67.7	65.6	96.8

Table 8. Common repair measures for leaking components.

Component type	Repair measures
Pump	Tightening packing; Replacing packing materials
Valve	Tightening valve packing glands; Replacing valve packing or valve stem
Flange	Tightening/adjusting flange bolts; Replacing flange gaskets
Open-ended line	Installing caps, plugs, double blocks, purges, or drains
Non-flanged connector	Tightening the bolts and screw caps; Rewinding the sealing tape; Re-smearing the sealant

Table 9. Numbers of DOR components in different refineries.

Refinery	Pump	Valve	Flange	Open-ended line	Non-flanged connector	Total
A	0	53	41	24	27	145
B	0	35	9	4	10	58
C	1	57	52	89	9	208
D	0	89	65	44	129	327

Table 10. Number of leaking components and VOC emissions after repair.

Refinery	Number of leaking components	Total VOC emissions from all components (tons/year)	VOC emissions from leaking components (tons/year)	VOC emissions from DOR leaking components (tons/year)
A	262	38.4	24.9	21.4
B	101	76.5	36.7	32.3
C	231	59.8	51.2	50.8
D	581	210.8	59.2	31.6

Figure 6. Leaking components repair rate and VOC emissions reduction rates after repair.

Figure 7. Repair results of different component categories.

Figure 8. Repair results of different initial screening value ranges.

Figure 9. Results of LDAR implementation from 2016 to 2019.

Figure 10. Typical process flow of a refinery.

Table 11. Capacity of processing units (10⁴ tons/year).

Refinery	C(V)DU	CCU	CCR	GHT	DHT	GFU
A	300 ~ 400	160	60	70	160	30
B	400 ~ 500	180	60	90	100	35
C	400 ~ 500	140	60	60	200	20
D	> 2000	570	280	225	600	120

Figure 11. Number of components and VOC emissions in different processing units.

Table 12. Costs distribution of LDAR program for a medium refinery.

Category	Details	Percentage (%)
Instrument purchase costs	Five portable organic vapor detectors	3.33
	Five handheld portable data terminals	0.40
	One EyeCGas infrared camera	3.20
	One exhaust gas monitoring instrument	1.07
	Freight charges and miscellaneous costs	0.34
Instrument usage costs	Depreciation costs (a 5-year replacement life and 5% residual value rate per year)	1.45
	Instrument materials, maintenance, and calibration costs	1.45
Technical costs	Project establishment for flexible research	7.46
	Labor costs of LDAR log establishment and component monitoring	49.80
	Organized monitoring	2.40
	VOC emissions inventory and calculation cost	5.60
	LDAR management platform authorization and operating costs	8.54
	Tax	4.00
Project construction and Other preparation work costs	Including preliminary work fees, construction and management fees, evaluation fees, and insurance	10.96

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