Abstract

In the composting process ammonia develops from the decaying of organic matter. A small amount of ammonia also comes from fertilizers, waste disposal sites and industrial processes. Ammonia is widely used in the Chemical Industry as a cleaning and bleaching agent in the production of fertilizers, plastics, and explosives just to name a few. As a result, large quantities of wastewater containing ammonia are produced and many industries now have to treat the wastewater to remove the ammonia so that it is not discharged back into the environment.

Ammonia in wastewater is present as ion where pH is neutral. Ammonia is separated as gas from wastewater by raising pH of water with alkaline addition. Increasing the operating temperature enhances separation.

In the usual commercial process of separating ammonias, the gases are passed through a sulphuric acid solution to cause a reaction between the acid and the ammonia in the gas, resulting in precipitation of ammonium sulphate crystals, which sink, to the bottom of the solution. A sludge of ammonium sulphate crystals and acid solution is then removed, the excess solution drained off, and then the ammonium sulphate crystals are dried in a Atmospheric Double Dryer Drum to remove as much of the acid solution as possible.

Provides either ammonia recovery process or ammonia decomposition process, determined by the amount of ammonia contained in steam at top of the stripper, or benefits of its recovery.

Project Snapshot

Composting Facility

City of Calgary Composting Facility

Roof Exhaust for Process of Heat and gas removal

Provide Fans to meet performance, reliability, and Environmental requirements

Challenges

Easton Industrial Air provided a Aerovent 36″ Fibreglass Axial fan constructed of a fire-retardant polyester resin with ASTME-84 Class 1 flame spread of <25. Included a one-piece fibreglass curb base with seamless construction. Bearing and belts are enclosed in an air insulated fibreglass housing to protect them from the airstream gases, fumes and vapours. All hardware is 316 Stainless Steel to avoid any erosion. A Stainless Steel velocity cone thrusts the exhaust up and away from the building. The fan also included the Ultra Violet Inhibitor to protect the resin from discolouring.

Easton Solution

HVAC equipment had to be corrosion resistant as it is exhausting steam from the Atmospheric Double Dryer Drums [ADDD] creates moisture and chemical exposure the exhaust fan. The exhaust is required to shoot up into the atmosphere as high as practical to allow the plume to be carried away from he buildings.

Fan housing and Propeller constructed of fire-retardant reinforced polyester resin. that extend more than 8 feet above the roof deck must be secured with guy wires. However, fans that satisfy the owner’s design specifications would extend nearly 12 feet above the roof.