Ecologix-DDI Heat Exchangers

Common Applications

• Cooling of Aerobically Digested Sludge
• Pre-heating of Raw Sludges
• Heat Extraction from Waste, Re-circulated hot water centrate or digested sludges
• Temperature augmentation of digested sludge prior to de-watering
• Heating or cooling of liquid products containing solids in fermentation, stabilization or sterilization

Industries

• Municipal waste water treatment
• Dairies
• Poultry and Pork operations
• Agriculture
• Breweries and distilleries
• Pulp and paper industries
• Mining, oil and gas
• Food processing plants

Ecologix-DDI Heat Exchangers for Heat Recovery Applications
The Ecologix-DDI Heat Exchanger introduces innovative technology with our square and rectangular shaped channels. In short, the flat edges of the channels aids in the heating process of the wastewater as opposed to round tubes that do not have sufficient surface area to help heat the wastewater as it flows through. Another advantage to this technology is that solids easily pass freely through the rectangular or cube shaped channels allowing a constant flow with no clogging or interruption in flow.

Recent energy cost increases and the introduction of anaerobic thermophilic process as part of municipal sludge digestion has prompted the use of Heat Recovery Exchangers. The DDI Heat Exchangers for wastewater treatment, dairy cow manure farms and many other applications can be used to heat sludge in a mesophilic digester (55°C, 134°F), or to conform to the new Class A solids disposal law, via heating to approximately (71°C, 160°F).

These non-pluggable heat exchangers are specifically designed for recovery from liquid materials containing large solids, such as municipal sludges. They can operate for (7) seven years without maintenance and are ideal for recovering wasted heat in wastewater treatment plants, preheating cold raw sludge with outgoing hot sludge, preheating raw sludge with hot liquid before anaerobic digesters and cooling digested sludge from thermophilic to mesophilic.

Since the Ecologix-DDI Heat Recovery Systems have a Minimum Gap of 2.75" on both sides (to avoid blockage) it makes no difference which side has Water or Sludge, or even both sides could have Sludge (for Heat Recovery).  We achieved our "Non-Plug" design (compared to the Spiral design) via large gaps, no obstacles and round curves. The Ecologix-DDI Series has achieved the possibility of having the same flow in both sides (for Heat Recovery), compared to Tube and Shell exchangers which cannot provide sufficient surface area (see the surface Heat Transfer area and flow area Comparisons below). The overall size is smaller than the Tube and Shell and does not require Grinders or Macerators. 

Advantages to the Ecologix-DDI Series Heat Exchangers with Square & Rectangular Channels

• Channels provide larger Heat Transfer Surface than traditional round piping
• Small footprint compared to tube units....typically 1/3 smaller footprint dimension
• More turbulence than tubular or spiral piping units and better Heat Transfer capability
• Non-Block design, no spacers or obstacles as in spiral type designs
• Gaps of 3" minimum meaning no sludge blockage
• No need for expensive Macerator & Blades to grind sludge
• Both sides have doors with full access to internals
• Designed for Optimum Height (Non-Plug) for each liquid
• Designed for Optimum Width, best Fast-Flows speed to avoid baking
• Very low maintenance required. Typically one maintenance every few years (Some competitive units require backflush after every shift)
• May be used for Municipal, Agriculture or Pulp & Paper applications
• May be manufactured from a variety of metals and alloys
• Modular system can be used for Water-to-Sludge or Sludge-to-Sludge Heat Recovery. (Back up units, while not in use, can be utilized as Sludge-to-Sludge Heat Recovery
• Minimum thickness of 0.25" which allows for Corrosion and Abrasions as well
• Heat Recovery can have monetary payback within the first year of operation