Clear The Air News Blog Rotating Header Image

Incinerators shown to be worst option; HK officials press with Shek Kwu Chau as ‘best option’

It is a bad plan that cannot be altered” – Publilius Syrus

Hong Kong officials are adamant about pressing ahead with the Shek Kwu Chau incinerator as the future for the city’s municipal solid waste treatment. After readers of the SCMP sent in suggestions to avert such a course, a representative from the Environmental Protection Department, Elvis W.K. Au, sent in a discombobulating response. It reads:

I wish to respond to the letters by Mary Melville on the disposal of food waste (“Environment-friendly fix makes molehill of food waste mountain [1]”, October 12) and Frank Lee on thermal waste treatment technologies (“Officials stick with outdated technology [2]”, October 24).

We have already examined the use of a food waste grinder. It merely transfers the food waste from the solid waste disposal system to the liquid waste disposal system without any enhanced treatment.

It would also increase both sewage pollution loads and the amount of sewage, with adverse impact on the existing sewerage network and sewage treatment works. The higher solid contents will lead to the need for higher sewer maintenance frequency and costs, as well as higher risks of sewer blockage.

In addition, a food waste grinder is not conducive to source separation of food waste. Its adoption on a large scale does not seem to be consistent with the philosophy of sustainable use of resources.

We will continue to reduce food waste and develop modern, large-scale organic waste treatment facilities using anaerobic digestion as the core technology.

The modern thermal waste-to-energy plant to be built near Shek Kwu Chau to deal with municipal solid waste (MSW) will be designed to meet the European Union Directive on Incineration of Waste, which requires very high heat flue gas combustion.

Plasma gasification technology is mainly used for treating industrial or special waste. Its commercial application for large-scale treatment of mixed MSW is uncommon and still has a limited track record.

The plant in Switzerland Mr Lee refers to uses pre-sorted waste, such as tyre chips and plastics, as alternative fuel to partially replace coal and coal is co-incinerated with limestone and other raw materials for cement production. This is different from the Green Island Cement proposal. All along, we have suggested to the company that it should conduct an environmental impact assessment.

The “White Paper on Alternative Waste Conversion Technologies” published by the International Solid Waste Association in January 2013 and the International Conference on Solid Waste held in Hong Kong in May 2013, affirm that modern moving grate incineration remains the mainstream proven technology for large-scale MSW treatment.

5 Nov 2013

(Readers can also find Ms. Melville’s letter here, and Mr. Lee’s letter here.)

One might be confused as to how such a patchwork of mumbling responses of a letter got past the printing presses at the SCMP, if only because it is a reply written by an official. Each of Mr. Au’s points demonstrates that there has been little work done in evaluating the suggestions for alternatives to the city’s municipal waste treatment, showing their fanatical resolve to stick to their plan of building the incinerator.

  • Mr Au says, “We have already examined the use of a food waste grinder. It merely transfers the food waste from the solid waste disposal system to the liquid waste disposal system without any enhanced treatment.” The purpose of the suggestion is precisely to achieve such an effect, and it does not pretend to provide enhanced treatment. Since Hong Kong’s food waste is more than 75% water, it actually makes little sense to call it ‘solid waste’, much less to dispose of it via the solid waste disposal system;
  • Mr Au says, “It would also increase both sewage pollution loads and the amount of sewage, with adverse impact on the existing sewerage network and sewage treatment works. The higher solid contents will lead to the need for higher sewer maintenance frequency and costs, as well as higher risks of sewer blockage.” It is unclear if this prediction is based on a proper evaluation or conjured from a whim. First, if food waste is going to negatively impact the sewage network, then one must wonder what impact the foods have on the human digestive system. Second, food grinders are made to be effective at pulverizing food solids into liquids, although Mr Au would be wise not to test this with his fingers. Third, the new sewage treatment plant at Stonecutters Island that will be operational in 2016 can handle 2.45million cubic meters of waste per day, well equipped for handling the daily food waste load of 3,500 cubic meters of Hong Kong;
  • Mr Au says, “In addition, a food waste grinder is not conducive to source separation of food waste. Its adoption on a large scale does not seem to be consistent with the philosophy of sustainable use of resources.” Mr Au can help make himself clearer by directly accusing citizens of hypothetically abusing the waste grinder for non-food waste, although it is unclear if Hong Kong citizens will be that obtuse as to try and grind down aluminium cans or plastic bottles;
  • Mr Au says, “The modern thermal waste-to-energy plant to be built near Shek Kwu Chau to deal with municipal solid waste (MSW) will be designed to meet the European Union Directive on Incineration of Waste, which requires very high heat flue gas combustion.” To be clear, a ‘modern thermal waste-to-energy plant’ is by no means permissible as a euphemism for an incinerator. An incinerator does not fulfill the function of waste-to-energy; the combustion of municipal waste, especially in the high-water-content type of Hong Kong’s, require the addition of fuels and materials sorted in recycling, which renders the recycling effort meaningless;
  • Mr Au says, “Plasma gasification technology is mainly used for treating industrial or special waste. Its commercial application for large-scale treatment of mixed MSW is uncommon and still has a limited track record.” At Clear The Air, we do our best to inform our readers, and hopefully all Hong Kong citizens, that municipal waste treatment plants using plasma gasification technology is currently being built around the world, including China, Thailand, and Indonesia, and will be operational within the next few years.

The letter also refuses to discuss the fact that incinerators are not only air-polluting but downright hazardous to human health. Perhaps one day, it will be revealed that there are special ‘benefits’ to this bad plan that the officials must remain silent on.

Leave a Reply

Your email address will not be published. Required fields are marked *