Wastewater Sludge Treatment Challenges

Wastewater sludge is also known as sewage sludge. Food and drink producers may also generate sludge as part of their operations. It is a major consideration for wastewater treatment plants around the world. It is an inevitable output of their operations and its disposal adds to operating costs. Sludge treatment is, therefore, an essential necessity. Sludge disposal typically occurs via one of two methods.

Wastewater Sludge Disposal Methods

In many countries sludge goes to landfill and, consequently, it contributes to global pollution. Sludge causes big problems as it still has water content. It drains and adds to the volume of leachate which landfills generate. Many countries build landfills without leachate containment measures. This subsequently causes huge problems due to leachate spilling over into clean natural water sources. Contaminated water then spreads to urban areas and is one of the biggest causes of diseases worldwide. This is notably and sadly the situation in many underdeveloped countries around the world.

Alternatively, sludge is often spread onto farmland as fertiliser. Although an easy solution, this potentially poses significant health risks. This is due to the fact that wastewater sludge can contaminate agricultural produce. It often contains a wide spectrum of heavy metals, pharmaceuticals, dioxins, flame retardants, polycyclic aromatic hydrocarbons, phthalates and many other chemicals and organisms. Some toxins can be present at low (considered safe) levels but others certainly are not. When applying sludge on land some harmful elements may end up into the actual fruits and vegetables we subsequently consume. As such, sewage sludge is not safe for use as land fertiliser and must be treated instead.

How Envitech Can Help With Sludge Treatment

At Envitech International we have an innovative and cost-effective solution for sludge treatment at the source. It eliminates around 85% of it within only 3 days. Meet the extremophile digestion technology which our partners Advetec Group have developed in the United Kingdom. Envitech is the authorised reseller of Advetec technology and products for the Republic of Bulgaria and the Dominican Republic.

Wastewater treatment plants need sludge treatment
Water polluted by wastewater sludge
Sludge spread on land as fertiliser

Introducing Advetec Group

Advetec head office

Advetec is a British manufacturer of unique biotechnologies which quickly eliminate organic waste. For over 17 years it has been building very efficient as well as scalable systems. They offer possibilities for eliminating organic waste which have not been seen before. The company operates internationally with headquarters in the United Kingdom as well as an office in Florida, USA. It serves big industrial, commercial and utility companies as well as smaller organisations.

Two unique technologies are at the core of the company’s solutions. Advetec XO™ enables processing of solid waste and wastewater sludge. Similarly, Advetec Bio-Reactor™ provides a solution for additional treatment of effluents. It quickly reduces the levels of critically monitored water quality parameters. All solutions are bespoke, scalable and installed at source in order to accommodate customer needs. They reduce (or completely eliminate) the high costs of waste disposal including transportation.

Advetec Group accreditation banner

What is Advetec XO™?

Advetec XO organic waste system logo
Advetec XO info sheet
Nitrifiers info sheet

Advetec XO™ (S) is an in-vessel engineered solution for sludge treatment. It quickly digests the organic content present in sludge. It has a small and flexible footprint and is installed at source. This is usually right at the end of the operational process at wastewater treatment plants. The system comes in sizes between 0.5-12 tonnes of daily throughput of sludge. In order to cope with larger volume requirements, we can integrate and link multiple systems on a single site location.

Extremophiles – An Evolution in Wastewater Sludge Treatment

At the core of the biological process is a unique extremophile biotechnology developed by Advetec Group. It features a special proprietary blend of deep ocean extremophile bacteria which almost completely digest organic matter, producing water in the process. The process is thermal due to the high temperatures the bacteria require in their environment.

Over the years, Advetec not only perfected the bacterial mix but also developed unique natural biostimulants. They stimulate both the extremophiles and the bacteria which naturally occur in organic waste. Subsequently they grow and digest organics quickly and effectively – within 2-3 days. The biotechnology comes in a neat engineered solution with a small and cost-effective design. You can visit our Resource Centre page to watch some interesting videos about the system.

How the Process Works

  1. Incoming wastewater sludge goes into the enclosed system.
  2. An automatic dosing system then disperses a bespoke blend of Advetec extremophile bacteria as well as biostimulants.
  3. An agitator constantly mixes the sludge in order to ensure optimal bacterial coverage.
  4. The biostimulants stimulate the proprietary bacteria as well as those which naturally occur in the sludge. Subsequently, they grow and digest the organic content of the sludge quickly and more effectively.
  5. The sludge treatment process produces heat and water in the form of vapour which is non-polluting. It vents out of the system into the atmosphere. Alternatively, a condenser unit (optional) converts it into water for recovery and reuse for irrigation or other similar purposes. Subject to additional purification, it can also become drinkable.
  6. The unprocessed (non-organic) part of the sludge comes out and is collected in a container. Typically, it is a very small proportion of the incoming sludge (around 15%) and has a very low moisture content (<10%).
  7. Notably, the entire process is odour free. In addition, Advetec staff remotely monitor all parts of the system including exit gas quality. This ensures a pollution free operation.
Advetec XO sludge treatment schematic

Unique Aspects of Advetec XO™

  • Proprietary bacteria digest up to 85% of wastewater sludge within 3 days and at source. No transportation is necessary which saves significant costs

  • The system is scalable and flexible. It can process between 0.5 – 12 tonnes of sludge daily. We can install multiple systems for greater capacity requirements

  • A small and efficient footprint is a unique feature of the system which requires little space

  • The system is inexpensive whose typical payback period in the UK is between 18-24 months

  • We optimise and tailor the system according to customer needs and site requirements

  • The system is portable and can serve multiple sites in close proximity

  • The system is simple from engineering point of view and consists of standard readily available components

  • The sludge treatment process is fully automatic as we integrate the system into the plant infrastructure

  • Energy requirements to run the system are minimal due to the process sustaining generated heat

  • Dedicated staff monitor and optimise the system remotely at the Advetec control centre in the UK. An integrated PLC control panel by Siemens and a SCADA system with sensors controls the system and allows remote monitoring and data storage

  • Most of the output is water, which due to the heat is in the form of warm vapour. It is non-polluting and simply vents into the air. There are options to capture and reuse water if required

  • The system is odour free and environmentally friendly. It produces only traces of CO2 due to bacterial respiration


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You Can Benefit

You can significantly reduce your waste disposal costs and improve your green credentials. Whether you are a municipality or a business of any scale, we can help you with the right solution. See below for more info.