Monitoring & Alarm Software Helps Renewable Energy Process

From WIN-911 Software

Increased demand for renewable resources coupled with rising energy costs and a global movement to reduce greenhouse gases (GHGs) is fueling growth in the anaerobic digestion market. Anaerobically digested waste creates biogas, a renewable energy source used to power engines and generators. Biogas also can be harnessed for vehicle fuel and has similar applications as natural gas.

The market is demanding resources to protect the environment, and anaerobic digestion is an effective way to do that. Captured methane is an alternative to petroleum products.

According to the World Biogas Association, anaerobic digestion has the potential to reduce global GHG emissions by aboutf 13%. And the market is forecasted to reach $15.3 billion by 2025. Because only 5% of food waste is recycled with the rest ending up in landfills, tremendous opportunity exists for this technology.

Quasar Energy Group

Founded in 2006, waste management and renewable energy firm Quasar Energy Group (Quasar), Cleveland, designs and builds anaerobic digesters — industry-scale machines that convert solid waste such as manure and food processing scraps into methane gas and carbon dioxide, keeping the waste out of landfills. The company handles everything from manure generated by feedlots to biosolids produced by municipal waste-water treatment plants, and targets the agricultural and wastewater treatment sectors.

Quasar employs engineering, construction, regulatory and research and development staff to verify their systems remain on the cutting edge of renewable energy technology.

One impetus for the company’s growth has been stringent regulations on discharge quality from the U.S. Environmental Protection Agency (EPA) enacted in 2013. Many treatment plants were having trouble meeting the new limits and securing funding to support necessary capital upgrades. Over the years, the company has entered into Private-Public-Partnerships with municipalities.

Wastewater Treatment Plant Digesters

More than 16,000 municipal wastewater treatment facilities are in operation nationwide, and many need immediate help in treating the massive amounts of domestic sewage produced.

The energy hidden in wastewater is an untapped resource with the potential to offset 12% of the U.S. electric demand. The aging wastewater treatment infrastructure is facing capital, technical and regulatory challenges. Facilities are progressively required to improve pollutant loading reductions mandated by the Clean Water Act. Upgrading to high solids digesters can address these infrastructure improvements without passing the costs on to ratepayers.

Biosolids are pumped into stirred tank reactors, where they can be co-digested with outside organic waste. As anaerobic bacteria break down the volatile solids in the digester, biogas is released and can be combusted to generate electricity. This electricity can be net metered on-site with the potential for the wastewater treatment plant to become a net-zero facility.

How the Process Works

Energy is in the waste stream that goes to every wastewater treatment facility. Quasar capitalizes on the energy that’s in the solids’ organic fraction coming into these plants.

In anaerobic digestion, complex bacteria breaks down organic matter to produce biogas or a left-over “digestate” used for fertilizer or animal bedding. Multiple organic materials can be combined in a practice known as co-digestion, ideally increasing biogas production from low yielding or hard-to-digest waste.

The process begins with the delivery of liquid or solid organic waste. Liquid material is pumped into underground storage tanks, and solid waste streams are delivered into the hopper where they’re diluted and macerated.

The material is then pumped into the biomass equalization tank, where the breakdown of material begins. Incoming waste streams are mixed for three days and then pumped into digester tanks, where it’s continuously mixed and broken down by anaerobic bacteria for between 18 to 30 days.

Quasar operates with just-in-time logistics, meaning that raw materials are received the moment they’re needed and in the exact amount to reduce inventory cost and waste in the supply chain process. Within a water resource recovery facility, the solids receiving, digestion, co-generation and effluent management operate via just-in-time logistics.

Asset and Security Challenges

Because of the critical nature of their systems, each Quasar component is closely monitored to make sure there isn’t any breakdown. Any unplanned downtime in even one of the machines would be extremely costly as well as detrimental, and the entire process would have to literally start over. To prevent this, the systems must be monitored 24/7 to avoid the loss of costly inventory.

The operators also needed a solution to monitor the assets with real-time data and allow them to communicate remotely.

Additionally, to increase cybersecurity, Quasar wants the operators to have access to only the information they need from SCADA, but not access to the SCADA itself or its operating system host.

Monitoring Performance

Speaking with water and wastewater utility customers and through their relationship with Rockwell Automation, Quasar leaders learned about WIN-911 Software and how its advanced remote alarm notification software could be well-suited for Quasar’s challenges.