Strategic use

Dust control cannons in use for demolition and building material recycling

1 Eastland Shopping Mall prior to opening in 1957

2 The vertical angle can be adjusted to address activities on the ground or at the roof top

3 The newest addition to the Adamo Group fleet ready to be positioned to control dust

4 Highly maneuverable, the mist cannon can be adjusted to correspond with fluctuations in wind direction

BossTek, spezialised in industrial mist cannon technology helped a demolition contractor control dust emissions from several different material types to stay compliant and improve air quality. The manufacturer of the DustBoss^® family of dust control cannons understands that when several different types of materials are demolished and separated into recycling or waste piles, they release different kinds of dust that can be a challenge. Working closely with The Adamo Group on a large mall demolition involving several materials, the versatile DustBoss cannons were strategically used, resulting in zero dust emissions, no complaints and no costly violations.

The Adamo Group is well aware of the issues associated with the demolition of different projects. Operating since 1964 and headquartered in Detroit, Michigan, the company has safely and expertly demolished and cleared projects across the region. The company is very familiar with the wide variety of materials that can go into construction. “Our business model is to employ the best practices for any project, which includes diligent recycling and effective dust control,” said Al Penrod, Equipment Manager of Adamo Group.

Equipment and expertise

Consistently updating operations using modern methods and equipment is at the core of why Adamo has been a top demolition contractor in the North America. With a US$ 25 million fleet of modern machinery, the company provides a wide range of services. One of the company’s recent projects involved the demolition of the Eastland Shopping Center in the town of Harper Woods, Northeast of Detroit. Opened in 1957, the Eastland Shopping Center was considered one of J.L. Hudson Company’s most ambitious department store expansion projects, but occupancy began to wane and the property was sold.

The entire demolition project from start to finish took 8 months. Using several pieces of equipment in the fleet, including a mid-sized high-reach crane, front loader, magnetizing machine, etc., the Adamo Group dismantled the structure. An integral part of this was the DustBoss^® DB-60 misting cannon. Directed toward the activity area, the fine engineered mist raised the humidity of the area, preventing dust from becoming airborne and traveling into the surrounding community, as well as protecting workers on site from hazardous dust.

A second DB-60 unit was used to reduce dust emissions from separating, piling, short-term storage, and disruption of the piles while filling transport canisters. “These structures collected over 60 years’ worth of dust, so the separated materials can release a lot of emissions,” said Penrod. “The DustBoss really helped us control air quality so we could stay compliant.”

Controlling demolition dust emissions

To capture small airborne particles, the droplets need to match the general size of the particles so that they can collide. The combined mass causes them to drop to the ground. Droplets greater than 200 µm, like those created by hoses or sprinklers, are large enough to cause a slipstream current to move around them, which actually repels smaller particles and leaving them to remain airborne.

Automated mist cannons like the DustBoss DB-60 produce droplets approximately 50 to 200 µm from a misting ring in the front which are propelled long distances by a powerful fan that pushes air through the rugged barrel. The droplets offer both airborne and surface suppression using only a fraction of the water required by hoses or sprinklers. They have proven to be more effective, cheaper to run over the long term and require no workers to operate.

Mist cannon technology

The two DustBoss DB-60 cannons are BossTek’s mid-sized fan-driven designs. Each cannon is 2.06 m wide, 2.97 m long, 2.19 m tall and weighs 816.50 kg. Mounted on roadworthy wheeled carriages, the cannons can easily be moved to where they are needed by a pickup or vehicle equipped with a hitch. The units have an adjustable elevation angle from 0 to 50°, with a throw distance of 60 m of fine mist propelled in a wide cone by a 25 HP fan running at 849.50 m³/min. When running with the optional 359° oscillation, each one can cover more than 11 600 m², which is more than 2½ standard American football fields by a single machine.

The cannons are equipped with a 38.10 mm cam-and-groove quick disconnect female hose coupling. Connected to municipal hydrants with variable pressure, the DB-60s require only 0.69 bar of constant pressure. Water passes through an in-line 30 mesh 595 µm filtration system that captures any impurities in the water that might foul the lines. The water then enters a booster pump where the pressure is increased to the adequate level needed for the 30 specially designed nucleating nozzles attached to a brass mandrel to fracture the water into millions of minuscule droplets. The use of a booster pump allows the DustBoss to use a fraction of the water of hoses, only up to 101 l/m.

Success

The general rule for demolition dust is to avoid any situation that yields complaints from the public, as complaints regarding air quality submitted to the city or local EPA can trigger an inspection. Like most of Adamo Group’s projects, no complaints were lodged for the Eastland Shopping Mall demolition.

The addition of more robust dust suppression means that the company can have two units on large projects or split them between smaller projects as needed. This ensures that projects can keep operating in adverse conditions where dust may have been a problem in the past.