An Incinerator for Municipal Garbage in Geelong

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1. Drivers for a better system of garbage incineration

A revolution in incineration of household garbage began in Melbourne during the late 1920s. Two Sanitation Engineers (John Boadle and Vasilie Trunoff) employed by the Melbourne City Council at their huge CBD incinerator recognized the serious limitations of conventional incinerators, and decided to come up with a better design.

At this time, Melbourne had experienced a huge boom in population as a result of the gold rush after the 1850s. As the population drifted to the outer suburbs in the late 1800s, with the advent of tram and train lines, the health aspects of sewage as well as garbage disposal became an ever-increasing concern of Council Health Inspectors, with outbursts of diseases such as cholera, dysentery, typhoid etc. driving incentives to do something about safer disposal of these hazardous materials.

After the innovative Melbourne Sewerage Scheme¹, the next phase had to be incineration of garbage. The outbreak of bubonic plague in Sydney in the early 1900s prompted the Victorian Public Health Board to recommend that all Councils incinerate their garbage², since this was considered more hygienic than open dumping or ocean disposal. Open dumping encouraged infestation by rats, flies, cockroaches etc, which were known vectors for diseases. Fires were sometimes lit by fossickers in the dumps, generating awful stinks – and at least one child killed after stepping into burning garbage in Geelong³.

The problem was that Councils in the outer suburbs, as well as regional towns, did not have the rate base to afford the high cost of building and operating conventional incinerators. Early studies by the Geelong Council Surveyor and Aldermen put the capital cost of conventional incinerators at around £20 000⁴; Council understandably rejected this proposal. Boadle and Trunoff developed an incinerator system that was lower in capital cost, in operating costs, and more hygienic in operation than the huge, complex and cumbersome steam-boiler systems that were then the state-of-the-art.

2. How did the Boadle system work?

The two engineers decided that the best way of simplifying an incinerator was to get rid of the steam boiler, and all its ancillary equipment. And to make the whole system simple to operate, so that relatively unskilled workers could understand its systems and control the furnace readily. They did this by replacing the steam boiler with a brick-lined reverberatory furnace, of a type commonly used at that time in the copper-smelting industry. To improve its thermal efficiency, a drying stage was added for garbage – and heat was recovered from waste flue gases to preheat the drying/combustion air for the furnace—and an afterburner section to fully combust soot/tars/char components that were responsible for causing ugly and smelly black smoke from chimneys. The tipping section of the building was put under negative pressure, so that smells and flies from tipping or the feed bins did not waft out into the nearby community.

The first installation using their concepts was an incinerator for Sandringham Council in 1926. The offer was sweetened by the partners (now trading as the Reverberatory Incinerator Coy, RICo) paying for the installation costs themselves, with payback from Council only if the incinerator performed to specifications. It did! Another with an improved design and layout (thanks to Box Hill’s Engineer Mr Frederick Kerr) was soon built at Box Hill in 1927, which delivered on all its promises. After inspection visits to Sandringham and Box Hill, with a positive report from its Surveyor + Chief Health Inspector, Geelong decided to go ahead also with its unit in Spring St, Belmont (at the western edge of South Geelong Tip?) operating in late 1928⁵.

3. What did Geelong’s Incinerator look like?

Since no photograph of the Geelong incinerator has been found to date, we can assume that it was similar to the Box Hill unit (see pic below), since the specifications and capital cost were similar. It was likely to be a brick building on two levels, built on a slope of the existing abandoned clay quarry which was being used as a garbage dump by Council. The upper floor was where the garbage was tipped by horse-and-cart, or truck, into a concrete bin. The garbage then flowed by gravity onto the drying grates of the brick-lined furnace. Hot air (at about 200 – 250°C) was blown up through the grates to dry the garbage first. It was then raked down onto the burning grates, where a fire was maintained at about 850 – 950°C with hot air blown up through the grates for combustion. The combustible components in dried garbage (paper, food, wood, bones etc) supplied enough fuel to maintain the temperature with little supplementary fuel (from an oil burner) needed.

Ash and clinker were raked out of the furnace, sprayed with water to cool them, then sent to be used as clean inert fill, much more stable and hygienic than raw garbage. Many of the sporting fields/parks around Melbourne used incinerator ashes as their base. The hot gases from the furnace were first mixed with air in an afterburner to complete combustion of all soot, tars, char etc which might cause a black smoke from the chimney; and then passed through a heat exchanger. An electric fan forced fresh cold air (collected from the tipping floor, deliberately to contain smells within the building) into the other side of the heat exchanger, thus providing the hot air to dry and then burn the incoming garbage.

4. Specifications and costs for the Geelong Incinerator

Throughput for the initial unit was specified by the City Surveyor (Mr HL Tisdall) at 10 tons per 8-hour shift (about 30 cu yds). The plan was to operate on day shift only, 5 days per week, using one man plus a boy per shift as operators. The capital cost was £2500; operating cost was around 5s 6d per ton, lower than open dumping costs⁶. After proving its performance, the incinerator was soon operating at full capacity, taking in garbage from adjoining Councils as well as all of Geelong’s.

Within a few months after startup, it was overloaded; a second shift was initiated, as well as allowing open dumping of the excess deliveries. A second furnace was ordered from the Reverberatory Coy⁷; cleverly, they anticipated that Councils would underestimate the growth of garbage in communities, so it was standard practice for the duo to provide space and ancillaries within the building to cater for a second furnace system. By late 1929, both furnaces were operating, and Mr Tisdell was kept busy hosting teams of delegates from other Councils⁸ wanting to examine his incinerator, gathering data for their own submissions to their Councils for new incinerators.

5. Fate of the Geelong Incinerator

The incinerator appeared to continue operating until late in 1938, when Council announced that it was closing down the operation of the incinerator and reverting to open dumping at the end of 1938⁹, but this time with “managed” dumping, presumably the modern practice of covering the day’s garbage with a layer of soil. Partial open dumping of garbage while the incinerator facility was still operating, as evidenced by the news report referred to earlier of children fossicking in the dump and getting burnt/injured. The reason given for closure was cost factors, with dumping now appearing to be more economic than incineration.

6. Transition to the Burley Griffin suite of Incinerators

The story didn’t end with the Geelong Incinerator. As noted above, the flood of inquiries/inspection tours that came with the successful installation and operation of the Geelong Incinerator sparked huge interest from other Councils in Victoria. Instead of incinerators being thought of as huge, complex, costly facilities that stank to high heaven and emitted plumes of filthy black smoke, here was a proven incinerator system that was low in capital and operating costs, simple to work, and with no stink or filthy stack plumes. To Councils struggling through the Great Depression of the 1930s, here was an answer to their needs to improve community health by getting rid of the evil health impacts of open dumping, without burdening ratepayers with a massive debt.

Boadle/Trunoff’s company found that they were overwhelmed by the demands of the flood of interest in their incinerator from Councils. They were still working full time at the Melbourne Incinerator, doing the RICo work in their spare time. Councils were requesting proposals, as well as a new demand for incinerators that were architecturally “appealing” (i.e. that didn’t look like an ugly blocky incinerator, and would fit into suburban locations).

Fortunately, Trunoff knew Nisson Leonard-Kanevsky through his migrant community. NLK was a successful entrepreneur, owning several rag-trade companies in Melbourne; NLK had already used Walter Burley Griffin to design for him the impressive Leonard House office building in Elizabeth St, Melbourne. So the logical outcome was a new company, with Boadle/Trunoff doing the Engineering work; Griffin Studios doing the architectural design work on the buildings housing the incinerator furnaces; and the brilliant skills of NLK to market the technology and manage the overall company.

The Reverberatory Incinerator and Engineering Coy (RIECo) was formed, and away it went. RIECo dominated the incinerator industry during the rest of the 1930s, building marvellously-designed incinerators in several Sydney suburbs; in Essendon; two in Adelaide; one in Ipswich; and one in Canberra. The furnace design used in Geelong was gradually improved, instrumented, mechanised, enlarged until it could handle large tonnages of garbage. None of these incinerators are still operating; several (e.g. Essendon, Willoughby, Ipswich) have Heritage listing, and have been saved from demolition and converted to cafes, art precincts, theatres.

References

[1] RD La Nauze, Engineer to Marvellous Melbourne (Aust Scholarly Publishing , Melbourne 2019)
[2] 28 Jun 1913, Richmond Australian, p3
[3] 23 Dec 1933, The Argus, p2
[4] 25 May 1927, Geelong Advertiser, p7
[5] 16 Nov 1928, Geelong Advertiser, p4
[6] 28 Mar 1928, The Age, p16; 1 Nov 1928, Geelong Advertiser, p2
[7] 23 Jan 1929, Geelong Advertiser, p4
[8] 26 Jun 1930, The Age, p14
[9] 30 Nov 1938, p11; The Argus