Marine sewage incinerator

Types of marine sewage incinerators

A marine sewage incinerator is designed to burn organic material found on ships and at sea. This includes food waste as well as any human waste or material that may have come into contact with humans. There are different types of marine incinerators based on how they burn material, design, and fuel source.

• By the burning process: In under-stoker furnaces, waste is placed on a grate or stoker, and air is blown underneath, which causes it to burn from the bottom up. This type of burn is uneven and may leave a lot of ash behind. In over-stoker burn, the air is blown on top of the waste, making it burn from the top down. Over-stoker burns more evenly and produces less ash. Over-stoker or upper air has a better burn efficiency and is more commonly used in modern incinerators.
• By design: An incinerator can be vertical or horizontal. Vertical incinerators are usually cylindrical with a vertical combustion chamber, whereas horizontal incinerators have a horizontal grate or floor to burn waste material. Both types of incinerators have primary and secondary combustion chambers. In the primary chamber, the moisture in the waste material is evaporated, and then the material starts to burn. In the secondary chamber, toxic gases are subjected to high temperatures to neutralize toxic compounds. Vertical incinerators take up less space, while horizontal ones are easier to access and repair.
• By waste feeding method: An incinerator can have manual or automatic feeding. In manual feeding, the waste material is fed by hand. In automatic feeding, the waste is fed automatically by a machine. Automatic feeding is more efficient and hygienic because it limits human contact with waste material.
• By fuel source: Marine incinerators can use oil, gas, or dual fuel, which is a combination of oil and gas. Gas burners are usually triggered by ignition coils or transformers. Oil burners are started by using a pump to send fuel oil through a nozzle, where it is atomized and ignited by a spark.

Fuel-efficient incinerators may have a conversion kit that allows them to be used with other fuel sources, such as natural gas or LPG. In some incinerators, the fuel injection system is controlled by a computer to optimize fuel consumption.

Specifications and maintenance of marine sewage incinerator

Specifications

The specifications of marine sewage incinerators may vary depending on the models and manufacturers. Here's a sample list of basic specifications.

• Capacity: The capacity of the marine incinerator is usually measured based on the total weight of sewage matter that it can deal with in an hour. For example, a typical capacity might be 1 ton/h.
• Temperature range: The incinerator needs to burn sewage at a certain temperature. The primary combustion chamber's temperature can be above 800°C, while that of the secondary one can be above 1000°C.
• Sizes: The length, width, and height of marine sewage incinerators can differ a lot from models to models. For example, some products may have a height of 3,535 mm, a length of 2,621 mm, and a width of 2,204 mm.
• Fuel type: Marine sewage incinerators can use different fuel types, such as diesel, heavy oil, MGO, methane, natural gas, etc.
• Emission standards: Marine incinerators' pollutant emission should meet specific standards set by various countries and regions. For example, the device's smoke should not contain visible black smoke, and the residue should be not more than 3% of the total weight of the burned sewage matter.

Maintenance

Proper maintenance of marine sewage incinerators is crucial to ensuring their effectiveness, longevity, and compliance with environmental regulations. Users need to develop maintenance schedules and carry out regular check-ups and maintenance tasks as per the manufacturer's instructions provided in the incinerator's user manual. Below are some general suggestions for the maintenance of marine sewage incinerators.

• Daily checks: Users need to carry out daily operational checks and ensure that there are no abnormal noises, vibrations, or signs of leakage. Check key indicators such as temperature, pressure, and combustion status to ensure the device works within the normal range. Also, users need to inspect the fuel supply system and ensure that there are no blockages or leakage. To put it more straightforwardly, the device needs to be treated much like a marine diesel engine that requires careful daily checks.
• Weekly maintenance: Clean the air intake and exhaust ports and ensure that there are no blockages. Check the sealing elements and efficiently prevent gas leakage. Users can also apply lubricants to components that require lubricants.
• Monthly maintenance: Conduct a thorough cleaning of the combustion chamber and ash discharge system. The residue and ash can cause blockage and slow down the device's efficiency, and therefore, regular cleaning is essential. Inspect the fuel supply system and ensure that there are no blockages or leakages. Users should also check the performance of the fans and pumps, ensuring that they work well. After the inspections, users should also adjust and calibrate the parameters of the device.
• Quarterly maintenance: More thorough cleaning and inspections should be carried out quarterly or after a specified number of operational hours. These tasks may include the cleaning of smoke passages and heat exchangers, the inspection, repair, or replacement of wear parts, etc. Also, users should carry out more thorough checks for critical components such as the combustion chamber's integrity and sealing elements. Besides, users should conduct analyses of the emissions and ensure that they conform to the relevant environmental standards set by the authorities.

In addition to the above regular maintenance tips, users should also establish a regular preventive maintenance system for the sewage incinerator, which may include periodic high-frequency cleaning, inspections, repairs, and replacement services for critical components. Users should consult the manufacturers or relevant specialists to get a more tailored preventive maintenance plan.

Application Scenarios of Marine Sewage Incinerators

The application scenarios of marine incinerators are mainly concentrated on the maritime industry and the management of hazardous waste on various kinds of land. The maritime industry includes coastal cities, marine farms, marine tourism, and the maritime transportation industry, such as the cruise industry and cargo industry. Land-based scenarios may include the hazardous waste treatment plant or a medical facility. Some major application scenarios for a marine incinerator include the treatment of waste on ships and boats, the farmland, the marine environment, and coastal cities and towns.

• Waste Treatment on Ships and Boats

As a waste treatment facility onboard the vessel, a marine incinerator is mainly designed to dispose of marine sewage, reducing the volume of garbage generated on the vessel, including medical waste and food waste. By combusting the waste, the putrid smell and pollution of the vessel are eliminated.

• Marine Environment Protection

For sustainable development, protecting marine life is crucial. The proper disposal of sewage and waste is essential to minimize maritime pollution. Using marine incinerators correctly can help reduce water pollution and preserve marine ecosystems.

• Coastal Cities and Towns

Coastal cities' convenience of land and proximity to the sea often results in a higher risk of water pollution. Installing marine incinerators on vessels can help mitigate marine pollution and contribute to environmental sustainability in coastal urban areas.

How to choose marine sewage incinerators

Choosing a marine sewage incinerator requires a thorough understanding of the ship's sewage generation, disposal methods, environmental regulations, and equipment performance.

• Sewage volume analysis

  Conduct a comprehensive analysis of the sewage volume generated on board the ship each day, typically measured in kilograms or liters. Consider factors such as the number of crew members, the duration of the voyage, and the usage of onboard facilities (e.g., kitchens, bathrooms).

• Available disposal methods

  Consider the incinerator's placement so that the transportation cost is acceptable. Apart from incineration, other disposal methods may include treatment and discharge into the sea (subject to compliance with relevant regulations) or disposal at designated onshore facilities.

• Environmental compliance

  Choose a vessel sewage incinerator that complies with the incineration directives. Ensure the selected device meets the emission standards and holds the necessary certification to comply with the relevant environmental regulations.

• Technical parameters

  Consider the technical parameters of the intended incinerator, such as its combustion capacity, combustion efficiency, and waste heat utilization system. Opt for an incinerator with high combustion efficiency to minimize fuel consumption and reduce environmental impact.

• Operational and maintenance requirements

  Consider the operational and maintenance requirements of the proposed incinerator. Evaluate the user-friendliness of the control system, monitoring capabilities, and automation features. Additionally, examine the maintenance requirements, availability of spare parts, and support services to ensure smooth operation and timely maintenance of the device.

Marine Sewage Incinerator FAQ

Q1: How does a marine incinerator work?

A1: Marine waste incinerators burn waste materials at extremely high temperatures to convert them into ash, gas, and heat. The following parts can generally be found in marine incinerators: feeder or hopper, combustion chamber, furnace, treatment system for flue gas, and cooling system. Materials are stored in a feeder or hopper, where they are further processed and eventually placed into the combustion chamber. Some materials may require pre-combustion procedures; therefore, they may be placed in a furnace with lower temperatures to undergo such treatments. The main part of the marine waste incinerator is the combustion chamber, where materials are burnt at high temperatures. What is left after the burning of materials are flue gases that are treated by flue gas treatment systems so that no hazardous elements can harm the environment. Lastly, a cooling system may also be necessary for the incinerator to cool down the overall temperature.

Q2: What are the advantages of waste incineration?

A2: Waste incinerators can reduce the overall volume of waste by 90 to 95%, leaving behind only ash that can be easily disposed of. Waste incinerators generate heat energy after burning the waste material, which can be used for many purposes, like powering a facility or being used in district heating systems. Waste incinerators can also prevent the contamination of soil and water resources caused by the decaying process of organic waste materials.

Q3: What are the disadvantages of incineration?

A3: Waste incineration may release harmful substances into the environment and the air, such as dioxins, heavy metals, nitrogen oxides, particulates, and acid gases. Incinerators require constant monitoring to keep track of the emissions and ensure they are within the limits set by authorities. The ash produced by the marine sewage incinerator should also be disposed of properly, as it may still contain some hazardous materials. Moreover, the initial costs of incinerators may be higher than those of landfills.