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This article is about studying GB-T 4795-2023 Marine Bilge Water Treatment Device. The study notes are compiled and shared in the hope that more people will benefit. If there is any infringement, please contact us in time.
1 Scope
This document specifies the bilge water separator (hereinafter referred to as the separator) and the bilge water separator (hereinafter referred to as the separator) in the marine bilge water treatment device (hereinafter referred to as the treatment device).
Requirements, test methods, inspection rules, marking, packaging, transportation, storage, etc. for water alarm devices (hereinafter referred to as alarm devices).
This document applies to the design, manufacture and acceptance of treatment devices with a rated processing capacity of 0.1 m³/h ~ 50 m³/h.
2 Normative reference documents
The contents of the following documents constitute essential provisions of this document through normative references in the text. Among them, for dated referenced documents
, only the version corresponding to that date applies to this document; for undated referenced documents, the latest version (including all amendments) applies to this document.
this document.
GB/T 191 Packaging, storage and transportation pictorial mark
GB/T 2423.1 Environmental testing of electrical and electronic products Part 2: Test methods Test A: Low temperature
GB/T 2423.2 Environmental testing of electrical and electronic products Part 2: Test methods Test B: High temperature
GB/T 2501 Marine flange connection dimensions and sealing surfaces
GB/T 6994 Definition and general provisions for ship electrical equipment
GB/T 11037 Strength and tightness test methods for marine boilers and pressure vessels
CB/T 3869 Technical specifications for tubular electric heaters for marine oil and wastewater separation devices
CB/T 4196 Marine flange connection dimensions and sealing surfaces
ISO 9377-2:2000 Water quality—Determination of hydrocarbon oil index— Part 2: Method using
solvent extraction and gas chromatography
chromatography)
3 Terms and definitions
The following terms and definitions apply to this document.
3.1
isokinetic samplingisokinetic sampling
The sample enters the sampling pipe at the average flow rate of the outlet pipe. Sampling can be achieved by controlling the sampling time. The sampling time is
Calculated by formula (1).
In the formula:
t—the value of the sampling time, in seconds (s);
……………………
(1)
V——The value of sample volume, in milliliters (mL);
R——The value of the radius of the water pipe of the device, in millimeters (mm);
Q is the value of the flow rate in the water pipe of the device, in milliliters per second (mL/s);
r—the value of the inner radius of the sampling tube, in millimeters (mm), r=3mm.
GB/T 4795—2023
3.2
ppm parts per million
The amount of oil in water, measured in parts per million by volume.
3.3
marine bilge water treatment device
_
Composed of a separator and an alarm device, it can handle all oily mixtures coming from the bilge where the machine is located, and can handle all kinds of oil that may be carried on the ship.
Effective on both oils and can handle extremely dense oils or mixtures in the form of emulsions.
Note: The discharge outlet of the device is equipped with an alarm device. Water that meets the standard after testing is discharged overboard, and water that does not meet the standard flows back to the ship's bilge or sewage tank.
3.3.1
bilge separator bilge separator
Any combination of separators, filters, coalescers or other filtration devices, or if the oil content in the effluent does not exceed 15
ppm
Designed as a single device.
3.3.2
bilge alarm _
It is an instrument that detects the oil concentration in the outlet water of the treatment device. When the oil concentration in the outlet water reaches the set value, the device issues an alarm.
4 requirements
4.1 Appearance
4.1.1 Separator
4.1.1.1
The surface coating of the separator should be smooth, uniform, and free of obvious mechanical damage and paint peeling.
4.1.1.2 The inlet and outlet pipelines of the separator should be arranged neatly.
4.1.2 Alarm device
4.1.2.1
The surface coating of the alarm device should be smooth, uniform, and free of obvious mechanical damage and paint peeling.
4.1.2.2 The signs should be clear and firm.
4.1.2.3 Equipped with ppm
display, which can clearly and accurately display various data (such as current time and current ppm value, etc.).
4.1.2.4 All connectors and fasteners are firmly connected and there is no looseness.
4.2 Design and structure
4.2.1 Specifications
The rated processing capacity of the treatment device includes 0.10 m³/h, 0.25 m³/h, 0.50 m³/h, 1.00 m³/h, 2.00 m³/h, 2.50 m³/h, 3.00 m³/h, 3.50 m³/h, 4.00 m³/
h , 5.00 m³/h, 10.00
m³/h, 15.00 m³/h, 20.00 m³/h, 25.00 m³/h, 50.00 m³/h.
4.2.2 Separator
4.2.2.1
The separator consists of main parts such as processing components, supporting pumps and electric control boxes.
4.2.2.2
The supporting pump of the separator should be a positive displacement type. Under rated working conditions, the displacement should not be less than the rated processing capacity of the separator, but not exceed
110% of the rated processing capacity.
4.2.2.3
The electric control box should at least have functions such as pump start, stop, and oil discharge control. If the separator is equipped with monitoring equipment for the oil content of the discharged water
, the electric control box shall have the control function to stop the pump or discharge it back to the bilge if the oil content of the discharged water exceeds the standard. Other requirements shall comply with the requirements of GB/T 6994
.
4.2.2.4
The separator should be equipped with an automatic oil drainage system. For a multi-stage separator, except for the first stage, all subsequent stages can be manually drained, but they should
GB/T 4795—2023
It has the function of monitoring and alarming the oil-water interface. There should be a water detection cock or oil-water interface at the same horizontal position as the oil-water interface sensor of the oil discharge system.
surface observer.
4.2.2.5
The automatic control part of the separator heating and oil discharge should be able to be converted to manual control.
4.2.2.6
The separator should be able to operate with normal functions for at least 24 hours when left unattended.
4.2.2.7
The suction pipeline of the pump supporting the separator should be equipped with equipment that can remove solid impurities.
4.2.2.8
The vertical part of the inlet and outlet pipes of the separator should be equipped with a sampling device in accordance with Figure 1 to achieve equal motion sampling.
Unit is millimeters
Figure 1 Sampling device diagram
4.2.2.9
When the separator is equipped with an electric heater, it should have an over-temperature protection function.
4.2.2.10 The electric heater used in the separator should comply with
the regulations of CB/T 3869.
4.2.2.11
The fragile movable parts of the separator should be easy to access and repair.
4.2.2.12
The installation arrangement of the alarm device should be such that the time required from when the oil content of the separator discharge water exceeds 15 ppm
to preventing discharge overboard shall not exceed 20 s in any case.
4.2.2.13
The structure of the separator should be suitable for use on ships, and attention should be paid to its placement on the ship. If the separator is located in
a location where flammable air may be present, the safety regulations for such spaces shall be complied with. Electrical equipment that is part of a separator should be located in a non-hazardous area or should be
certified by the competent authority as safe for use in hazardous areas. All moving parts located in hazardous areas should be arranged with anti-static measures.
4.2.2.14
The separator should be designed to operate automatically and have fault protection measures to avoid any emissions in the event of a malfunction.
4.2.2.15 The separator should be able to resist corrosion under marine environmental conditions.
4.2.3 Alarm device
4.2.3.1
The alarm device consists of detection components, recording components and other main parts.
4.2.3.2 The alarm device should be equipped with measures to prevent deliberate manipulation:
a)
Every time you open a key component of the alarm device (such as the door of the recording component box, etc.), you need to remove the seal and activate the alarm;
b) Whenever clean water is used for cleaning work or zeroing, the alarm should be activated.
4.2.3.3
The recording component of the alarm device can record the date, time and alarm status as well as the operating status of the processing device. The recording component should also
store data for at least 18 months and should be able to be displayed or printed. If the alarm device is replaced, means should be provided to ensure that the recorded data can be retained on board
for 18 months.
4.2.3.4
Devices should be installed on the ship to check the zero drift of the instrument, the repeatability of the readings and the zero recovery capability.
GB/T 4795—2023
4.3 Performance
4.3.1 Separator performance
4.3.1.1 Safety valve trip pressure
The safety valve or other overpressure protection device of the separator should be able to operate when its opening pressure is 1.05 times the maximum working pressure.
4.3.1.2 Strength of pressure vessels
The strength of the pressure vessel of the separator should be able to withstand 1.5 times the design pressure without structural damage and permanent deformation.
4.3.1.3 Confidentiality
The tightness of the separator after assembly should be able to withstand 1.25 times the design pressure, and all components should be free of leakage.
4.3.1.4 Oil separation
4.3.1.4.1
Feeding oil, emulsified bilge water or air to the separator shall not result in any mixture discharged overboard with an oil content exceeding
15 ppm。
4.3.1.4.2 The separator should be able to separate test liquid B with a density of not less than 830 kg/m³ at 15°C
to test liquid A with a density of not less than 980 kg/m³, and test liquid C with an emulsion mixture content of 6%. .
4.3.1.4.3
The separator should be able to separate oily wastewater with an oil content of 0% to 100%, and when the feed liquid of the separator changes from oily water to oil, or from
oil to air, or from water to air. , the oil content of the discharge water should still not exceed 15 ppm.
4.3.1.4.4 The separator performance test should be able to separate the following oil-water mixtures:
a) A mixture of test liquid A and water with an oil content of 0.5% to 1.0%;
b) A mixture of test liquid A and water with an oil content of 25%;
c) 100% test liquid A;
d) A mixture of test liquid A and water with an oil content of 0% to 25%;
e) A mixture of test liquid B and water with an oil content of 0.5% to 1.0%;
f) A mixture of test liquid B and water with an oil content of 25%;
g) Oil-water mixture with an emulsion mixture content of 6%.
4.3.1.5 Discharge water pressure
Under the operating conditions of the separator in Table 1, the oil content of the treated discharge water should not exceed 15 ppm.
Table 1 Separator operating conditions
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GB/T 4795—2023
4.3.2 Alarm device performance
4.3.2.1 Accuracy
Unless otherwise specified, the accuracy of alarm devices is ±5 ppm.
4.3.2.2 Contaminants and color development
When there are contaminants other than oil in the oil and water sample liquid, the alarm device should be able to work normally.
4.3.2.3 Pressure and flow
When the pressure or flow rate of the oil and water sample is within the range of half to twice the normal value, the alarm device should work normally.
4.3.2.4 Close
If the alarm device breaks out of fluid during continuous operation, it should be able to work normally after the fluid supply is restored.
4.3.2.5 Energy supply variability
The alarm device should be able to work normally when its power source (compressed air, etc.) deviates from the design value by ±10%.
4.3.2.6 Response time
The response time of the alarm device is the time from when the oil and water sample sent to the alarm device changes to
when the ppm display shows the correct response.
The time should not exceed 5 s.
4.3.2.7 Alarm function
When the alarm device encounters the following abnormal conditions, the alarm function should automatically respond and have the function of outputting an alarm signal:
a) When the oil content in the effluent exceeds 15 ppm;
b) When it fails;
c) When warm-up time is required or normal operation is stopped due to other reasons.
4.3.3 Insulation resistance
The minimum insulation resistance of the separator's electrical control box and alarm device should meet the requirements of Table 2.
Table 2 Minimum insulation resistance table
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4.3.4 Withstand voltage
The electrical control box and alarm device of the separator should be able to withstand the power frequency (50 Hz or 60 Hz)
test voltage specified in Table 3 for 1 minute without any shock.
Wear or flashover.
GB/T 4795—2023
Table 3 Withstand voltage test table
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4.3.5 Power supply fluctuations
The electrical control box and alarm device of the separator should be able to operate normally when the voltage and frequency specified in Table 4 fluctuate from the rated values.
Table 4 Voltage and frequency fluctuation table
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4.4 Environmental adaptability
4.4.1 High and low temperature
The processing device should be able to work normally when the ambient temperature is 0℃~55℃.
4.4.2 Damp heat
The processing device should be able to work normally under the conditions that the relative humidity is not greater than 90% and the temperature is not greater than 55°C.
4.4.3 Tilt
The processing device should be able to work normally when the ship is heeling ±15°, rolling ±22.5°, trimming ±5°, and pitching ±7.5°.
The processing device shall function normally at all angles of any plane tilted from the normal working position to a maximum of 22.5°.
4.4.4 Vibration
When the frequency is 2.0 Hz～13.2Hz, the displacement is ±1.0 mm;
when the frequency is 13.2 Hz～80.0 Hz, the acceleration is 0.7g
, the processing device should function normally.
4.5 Interface
The connection dimensions of the external flange of the separator should comply with the relevant requirements of GB/T 2501 and CB/T4196.
GB/T 4795—2023
Further reading
More information can be found in GB-T 4795-2023 Marine Bilge Water Treatment Device. Further study
contact us
AQ 7015-2018 Safety Specifications for Ammonia Refrigeration Enterprises.pdf