The original steel piping that conveys low pressure sludge gas (LSG) from the digesters is corroded and leaking. Due to the corrosive nature of the LSG, King County has decided to replace the pipe with stainless steel. Triunity produced the construction drawings and specifications to support the replacement of several instruments, including pressure gauges, pressure transmitters, thermal mass flow meters that measure the digester gas production, and pressure switches that initiate alarms. A new radar-based level sensor design, developed by Triunity specifically for this project, is being added to measure the depth of the foam blanket that forms above the liquid in one of the digesters. The design addresses the associated modifications to the plant’s central control system, the new control wiring needed for the new instruments, and a new intrinsically safe raceway system suitable for the classified areas.

Triunity is supporting the construction phase with submittal review, RFIs, and change management. Triunity will also support the start-up and commissioning associated with the new instruments.