Solar-Thermal Pasteurization Technology

A proven system combining solar greenhouse drying, thermal pasteurization, and pelletization to provide an effective turn key solution for sustainable, long-term biosolids management.
Video Overview

Watch the Process Come Together

In this short overview, Ted Merrell walks through the Solar-Thermal Pasteurization process, showing how greenhouse drying, thermal pasteurization, pelletization, storage, and beneficial reuse all work together as one complete biosolids management system.

See each major stage of the system
Understand how the process fits together
Learn how biosolids become a reusable fertilizer product
A short visual overview of how Solar-Thermal Pasteurization moves material from dewatered biosolids to beneficial reuse.

Modern Treatment for a Changing Biosolids Landscape

Municipal wastewater facilities are under pressure. Disposal options are shrinking. Landfill capacity is tightening. Regulations are evolving. Odor concerns are growing. Transportation costs are climbing.

Solar-Thermal Pasteurization gives municipalities a better way forward.

Solar-Thermal Pasteurization is not just another treatment method. It is a long-term biosolids management strategy built around drying, pasteurization, pelletization, and beneficial reuse.

Biosolids Management Is Getting Harder to Ignore

Disposal Options Are Shrinking

Landfills and traditional outlets are becoming harder to rely on as capacity tightens and costs rise.

Odor Creates Public Pressure

Open or poorly controlled handling can create complaints, public concern, and pressure on utility leaders.

Regulations Are Tightening

Communities need treatment methods that support higher product quality, documentation, and long-term confidence.

Outdated Systems Limit Flexibility

Older storage, drying, and disposal strategies leave municipalities with fewer options as expectations shift.

Eventually, every utility faces the same question: what is the long-term plan?

A Smarter Path From Biosolids to Beneficial Reuse

Solar-Thermal Pasteurization combines the natural drying power of the sun with engineered process control.

Think of stepping into a parked vehicle on a hot summer day. Sunlight passes through the glass, heat builds inside, and the enclosed space becomes significantly warmer than the outside air.

Greenhouse pods use that same basic principle in a controlled industrial environment built for biosolids treatment.

The result: a process that helps municipalities reduce volume, improve odor control, lower hauling exposure, and create a product with beneficial use.
System Benefits

Designed to Solve the Problems Municipalities Face Now

Solar-Thermal Pasteurization addresses the full chain of biosolids pressure, from hauling and odor control to landfill reliance, compliance, beneficial reuse, and future planning.

Reduces Hauling Exposure

By removing moisture and reducing volume, the system helps decrease the amount of material that needs to be transported.

Improves Odor Control

Enclosed handling and controlled process flow provide a more managed environment than many traditional approaches.

Supports Regulatory Confidence

Thermal pasteurization provides a controlled path toward Class A and Class AA biosolids production.

Creates a Marketable Product

Instead of producing a disposal material, the process can create a cleaner fertilizer product for beneficial reuse.

Reduces Landfill Dependence

The system helps municipalities move away from landfill-dependent strategies and toward resource recovery.

Supports Long-Term Planning

Scalable greenhouse, pasteurization, and pelletization systems can be planned around future growth.

How Solar-Thermal Pasteurization Works

The system moves material through a controlled path from wet cake to market-ready fertilizer.

1

Dewater

Biosolids enter the system after existing dewatering.

2

Solar Dry

Greenhouse pods use solar energy and controlled airflow to reduce moisture.

3

Pasteurize

Time and temperature are managed to support pathogen reduction.

4

Pelletize

Treated material can be formed into a cleaner, uniform fertilizer product.

5

Reuse

The final product can be stored, loaded, bagged, or distributed.

Odor Control

Designed to reduce one of the biggest public concerns in biosolids management.

Odor is more than an operations issue. It can affect nearby residents, public perception, property development, and long-term confidence in the wastewater utility.

Odor control is built into the system.

Biosolids are managed through enclosed buildings and greenhouse pods, while process air is moved through dedicated odor-control systems before discharge.

How the process works

Enclose the process

Greenhouse pods and process buildings help contain odor-bearing air.

Move and manage the air

High-volume ventilation supports capture, airflow control, and treatment.

Treat before discharge

Odor-control towers and carbon filtration help polish captured air.

Proven in operating facilities

Municipal leaders and engineers can see the process operating in real-world facilities.

Why this matters

Better odor control helps reduce complaints, protect public trust, and support a more defensible long-term biosolids strategy.

Proven Facilities

See the System in Operation

Solar-Thermal Pasteurization is not a concept on paper. It is operating in real facilities and helping municipalities rethink what biosolids management can become.

Kennewick Washington
Request a Kennewick Site Visit
Pasco County Florida
Request a Pasco County Site Visit

Designed to Integrate With Existing Dewatering Infrastructure

Every wastewater treatment plant is different. That is why Solar-Thermal Pasteurization is designed to be evaluated around your facility’s existing process, site conditions, solids output, hauling costs, and long-term goals.

The system can work downstream of existing dewatering equipment, helping municipalities upgrade their biosolids strategy without replacing the entire treatment plant.

  • Current dewatering method
  • Wet tons or dry tons produced
  • Hauling and disposal costs
  • Available land or facility space
  • Odor concerns and regulatory goals
  • Desired end product

Patented Innovation. Proven Systems.

Merrell Bros., Inc. currently holds 7 issued U.S. patents with 6 additional patents pending, reflecting our commitment to advancing biosolids technology through real engineering innovation. These services (or systems/processes/technologies) incorporate proprietary technologies protected by one or more patents or pending patent applications.

Engineered In-House. Proven in the Field.

Our technologies are developed and refined by Merrell Bros.’ internal R&D and engineering teams, who remain at the forefront of responsible, performance-driven biosolids management. Our patented systems reflect continuous advancement in sustainable biosolids treatment and long-term infrastructure performance.

Ready to Rethink Biosolids Management?

If your municipality is facing rising disposal costs, landfill pressure, odor concerns, or long-term uncertainty, Solar-Thermal Pasteurization offers a practical path forward.

Talk With Our Team