The Importance of Food Waste Sorting and an Analysis of Processing Volume and Generation Volume
Text / By Upstream and Downstream reporters Duan Ya-xin, Lin Pei-jun
If African swine fever breaks out tomorrow, food waste will immediately become a battlefield. Is every place ready? "Upstream and Downstream" contacted local environmental protection bureaus and offices to obtain frontline information. This article takes stock of Changhua and Chiayi County; for other counties and cities, please read the special series.)
(Background note: The food waste recycling figures below are official statistics, but many food-waste pig farmers say that the official statistics on food waste are not accurate, because during the recycling process food waste has long existed in a situation of "reporting more while actually collecting less." Private operators drive small trucks with food waste bins on them and collect it everywhere in this way, mostly from households, snack shops, and night markets, and these may not be included in the statistics. Readers are asked to take this into account.)
Changhua County: About 119 tonnes of food waste circulate daily; cooked food waste was all used for pig farming in the past
The Changhua County Environmental Protection Bureau said that currently household food waste recycling is about 16.6 tonnes per day, and business food waste is between 16.6 and 33.3 tonnes. If food waste that is not recycled by cleaning teams and circulates outside is included, the amount is about 119 tonnes per day.
At present, raw food waste collected by cleaning teams is processed by composting. Section Chief Ye of the Environmental Engineering Section of the Environmental Protection Bureau said, "Compared with composting cooked food waste, composting raw food waste is less likely to draw protests." Therefore, starting last year, Changhua County fully and strictly implemented the separation of raw and cooked food waste. Raw food waste is mainly handled by the public composting site in Tianwei, which can process about 300 tonnes per day. Procedures such as applying to the central government to expand the composting site's capacity and applying for land have already been filed, with the goal of expanding to a composting capacity of 600 tonnes. Cooked food waste is handed over to pig farmers for pig feed.
If food waste pig farming is banned, in the short term it will first go to incinerators, and in the long term it will move toward composting and biomass energy centers
And if food waste pig farming is banned, what will Changhua County do in response? Section Chief Ye said that reduction steps such as crushing and draining off water will definitely be done first. In the short term, before facilities are in place, it will first go to incinerators; in the medium term, it will be handled by composting; and in the long term, in coordination with the central government's overall planning, food waste will likely be processed through biomass energy centers. However, biomass energy requires time in terms of cost, land construction, equipment, and so on. "This is the goal we want to achieve over the long term."
As for the processing capacity of Changhua County's incinerators, Ye said that after deducting the "general waste" and "business waste" that must be handled, there is still a surplus of 60 tonnes for burning other things.
Cherishing blessings is the source of food waste handling; Changhua City requires strict separation of raw and cooked food waste
Ruan Shun-ning, director of the Changhua County Environmental Protection Bureau, said that "cherishing blessings" is the source of food waste handling and also the link that can solve the problem best. Section Chief Ye also said that whether it is composting, incineration, or biomass energy, these are of course all methods to "dispose of" food waste, but if food waste is not reduced, all the later "methods" of processing are merely treating the symptoms. To truly address the root cause, it still has to start with the public, restaurants, and every person who eats.
The local cleaning team in Changhua City also has something to say. Zeng You-xin, captain of the Changhua City cleaning team, said that when Changhua City recycles food waste, it divides food waste into raw food waste and cooked food waste for recycling. "Because the subsequent handling is different, we collect them as two categories from the start." At present, of the food waste recycled daily in Changhua City, raw food waste is about 6 tonnes and cooked food waste is about 5 tonnes. After fermentation treatment, raw food waste is used as compost, while cooked food waste is given to pig farmers to feed pigs.
Zeng You-xin said that the collection of food waste is something that local cleaning teams everywhere are doing. As for the subsequent handling of food waste, such as composting, because conditions differ from place to place, composting requires sites, machinery and equipment, and manpower to handle, so not every place or county/city is necessarily able to do this part.
Since March of ROC year 107, Changhua City has been promoting food waste recycling, requiring the public and restaurant operators to properly separate raw and cooked food waste when dumping food waste, so that it is convenient for the cleaning team to carry out subsequent handling. If it is found during recycling that the waste has not been properly separated, they will require on-site separation, or separation after taking it back, and then wait for the cleaning team to come again the next day to collect it. But will the requirement to "send it back" cause backlash? Zeng You-xin said that sometimes there are indeed complaints, but most people, after communication, can understand and implement it.
Chiayi County: Food waste is cleaned and transported by the Environmental Protection Bureau, and pig farms take over to process it
According to statistics from the Chiayi County Environmental Protection Bureau, Chiayi County produces a total of 30 tonnes of raw and cooked food waste every day, including food waste from general waste and business waste, and in the past it almost all relied on pig farms within its jurisdiction and in surrounding counties and cities to take over and process it. Assistant Huang of the Environmental Facilities Management Section of the Chiayi County Environmental Protection Bureau explained that household food waste is recycled along streets by garbage trucks, and the cleaning and transport fees for food waste from snack shops and restaurants are collected together with water fees. "Since operators have already paid us to clean and transport it, they will not trade privately, so the Environmental Protection Bureau can grasp the amount of food waste more accurately." As for agencies that produce business waste food waste, they must commission outside handling themselves.
In terms of food waste recycling practices, in the past schools and agencies mostly handled it by tendering cleaning and transport operators themselves, while currently the Chiayi County Environmental Protection Bureau has begun providing food waste recycling services for schools and agencies. Junior high schools, elementary schools, and kindergarten units with food waste cleaning and transport needs may commission the Environmental Protection Bureau for help.
The Chiayi City Environmental Protection Bureau takes over the handling of food waste from schools and agencies within its jurisdiction. (Photo provided by / Chiayi City Environmental Protection Bureau)
Chiayi City did not separate collected cooked food waste in the past, making composting difficult; in the short term it can only use incineration first
In addition, Technician Wang of the Chiayi City Environmental Protection Bureau, who is in charge of business waste, also pointed out that business waste food waste is about more than 100 tonnes per month (including raw and cooked food waste). In the past, surrounding pig farms took it over through bids. At present, neighboring Yunlin County has completely banned food waste pig farming, so the Environmental Protection Bureau will guide operators to match with pig farms in Tainan, Pingtung, and Chiayi County that have obtained "reuse review," assist with the processing of business waste food waste within its jurisdiction, or require operators to pay to commission qualified clearing operators for handling.
Chen Yi-ru, section chief of the Agriculture, Forestry, Livestock, and Poultry Section of the Chiayi City Government, pointed out that Chiayi City has a total of seven food-waste pig farms raising 560 pigs, but in the past none of them passed the "reuse review." Although five are currently applying for "reuse review," one of the remaining farms cannot apply because its land conditions do not meet requirements, and another raises only two pigs and has no intention of transforming. However, she frankly admitted that the food-waste pig farms in Chiayi City are all small in scale, and investing further in equipment to use food waste does not meet economic benefits. In the future, they may still switch to feed-based farming or exit pig farming.
Regarding the three channels planned by the central government for food waste processing: composting, landfill, and incineration, the Chiayi City Environmental Protection Bureau said that the public in Chiayi City does not particularly separate raw and cooked food waste, and all of it is recycled mixed together. When used for composting, cooked food waste contains many impurities, is salty and oily, and has an unpleasant odor, so the production and operating costs to be paid are high. In the past, generally no operators were willing to invest. The only private composting site within the jurisdiction mainly makes organic fertilizer, and the raw materials it accepts are distiller's grains; it does not accept food waste.
In addition, Chiayi City also does not have suitable landfill sites, because most land is urban land, and repurposing land would also require changing land use regulations, so it is not a short-term method of food waste processing. Therefore, the facility currently best able to digest food waste is a garbage incineration plant in the West District of Chiayi City, which is expected to process 200 tonnes of garbage per day.
As for planning a long-term food waste processing plan, the Chiayi City Environmental Protection Bureau said it has applied to the central government for subsidies, hoping to set up its own fermentation treatment plant, for example to develop food waste power generation or produce organic fertilizer, in order to replace incineration.