Automation for Biosolids & Bioenergy Projects

Alpine Technology has developed a suite of dewatering and thickening optimization control systems over a period of 20 years. They are typically applied to belt filter presses, centrifuges, gravity belt thickeners, and clarifiers. Our focus is on the solids side of the wastewater plant, with an emphasis on optimizing biosolids as a fuel prior to a bioenergy process. We also optimize automatic blending of multiple feed streams to a reactor, including fuels such as biosolids, FOG (fats, oil and grease), and woodchip.

Our Dewatering Automation Control System (DACS) uses in-house algorithms to accept information from both field instruments and operator inputs, and optimizes the process within the preset parameters. DACS can be configured to manage a dewatering Unit Process in order to control the cake solids while simultaneously optimizing the consumables used, such as polymer.

The biosolids cake feed is controlled based on an operator entered set point, or on feedback from Alpine’s Mass Flow Control System. An online cake percent solids sensor can be included to further refine process control. There are many of these industrially hardened sensors in routine and reliable biosolids operation.

Key features of our DACS are:

• Optimizes polymer dose rate
• Optimizes solids capture in the centrate or filtrate
• Maximizes solids throughput
• Anticipates & responds to upset conditions
• Accounts for changes in feed solids over time
• Provides a steady-state feed to the downstream bioenergy process

When DACS is combined with a System Supplier’s bioenergy reactor process control system, the following benefits result:

• Operating Cost Reduction
• Minimizes auxiliary fuel consumption
• Increases reactor (thermal oxidizer, incinerator, gasifier) capacity
• Stabilizes oxygen content in exhaust flue gas
• Improves ease of operation
• Eliminates need for reactor spray cooling
• Maximizes primary heat exchanger life
• Reduces temperature fluctuations at inlet to reactor

Alpine has participated on over 50 full scale automation projects since the 1990s and we have a deep understanding of what automation components work, and equally important, what don’t. With this experience, our ideal project has a committed team who want to enhance overall process performance by at least 10%. There is an attractive payback from automation, extended equipment life, and the operations staff are freed from repetitive chores.