Tackling the impact of FOG in drainage systems

5 min read
The build up of fats, oil & grease can cause blockages in many wastewater systems.
The build up of fats, oil & grease can cause blockages in many wastewater systems.

According to Water UK, water and sewage companies in the UK respond to approximately 366,000 sewer blockages every year. In some parts of the country, fat, oil and grease build-up causes three quarters of these blockages. While household waste is always going to be a major contributing factor to FOG blockages in our water systems, many sewer obstructions occur because businesses and catering establishments, in particular, have inadequate procedures in place to dispose of FOG and food waste correctly.

Economic impact

FOG build-up is not just an issue in the UK. For example, Dublin council spends €1m every year maintaining the city's sewers. In 2008, it introduced a programme to battle so-called fatbergs, with excellent results. Compliance teams now carry out over 8,000 inspections a year, while Irish Water produces a risk map which helps to target inspections and inform preventative maintenance. The new procedures have reduced sewer blockages to just 50 a year and its last major fatberg blockage was more than six years ago, according to University College Dublin. Rather than waiting for FOGs to drain into the sewage network before addressing build-ups and blockages, facility managers in restaurants and food processing plants need to tackle the issue directly at source. Many businesses across Europe often think that if they have paid a fee to their local authority for the disposal of wastewater, their hands, along with their systems, are clean. However, this is not necessarily the case. On top of local authority fees, the actual treatment, cleaning and maintenance of drains and grease trap systems can cost businesses significant amounts every year. As a result, facility managers need to choose a treatment system that works.

Avoiding odours

Without treatment, drains and grease trap systems become blocked, resulting in emergency call outs and the potential structural damage of the facility. Additionally, without adequate drainage and waste processing systems, food processing or serving facilities run the risk of being non-compliant with environmental health and food standard regulations, leading to possible shutdown. Closure because of a breach of regulations could result in a damaged reputation and revenue. However, it isn't only the outcome of ineffective system management that can affect the public's opinion about a facility. Build-up of FOG can lead to complaints from customers and staff because of the foul odours that can be emitted when the organic waste begins to decompose. The unpleasant odours can attract vermin and insects, which can lead to breaches in health and hygiene regulations and increased risk of disease. It is vital for the build-up of decomposing waste to be effectively managed, rather than simply being deodorised or pushed along the pipework system. While there are products available to help combat the issues of FOG build-up and drain and grease trap blockages, many of them are harsh on the environment and can be hazardous to those tasked with handling and transporting them. Some chemical formulas can result in minor complaints like irritation of the eyes, nose or throat from fumes, or skin can become inflamed and painful should the solution come into contact with it. Repeated exposure can sometimes lead to chronic illnesses, which can last years

Manual maintenance

Many biological products are applied manually and under the wrong conditions. For example, applying treatment when the facility is busy and water flow is high means any treatment product is flushed through the system before it can take effect. Similarly, applying a treatment when cleaning processes are underway also diminishes the effectiveness of the treatment, particularly when disinfectants and hot water are in high use. When FOG and organic-waste blocks drains, emergency maintenance teams are called out to solve the issue, which is both expensive and can significantly disrupt operations. Blocked drain lines and grease traps can also cause flooding, which requires more manual unblocking. This process results in higher labour costs as well as risk of damage to drainage systems due to the manual removal of the obstruction. Sometimes, the build-up of grease and sludge inside grease traps necessitates excessive pump-outs of the system. Pump-outs are not only a disruptive and expensive burden for the business concerned, they potentially require the facility to close for a period of time. However, pumping out a grease trap does not necessarily remove the build-up of grease inside the drain line. It's important for facilities managers to remember that not all wastewater treatment products are created equal. Many biological products just contain dormant bacteria or enzymes, which are simply not effective. Enzymes liquefy the grease instead of digesting it, meaning the build-up problem is passed further down the drain and sewer system. There are other products on the market that contain dormant bacteria, which can often take many hours to become active, by which time they have already passed through the main part of the system which needs a new dose of treatment. Without treatment, FOG and organic waste can clog drain lines and grease traps leading to several unnecessary procedures. Many of these could be avoided had the right treatment been in place from the start.

A clearer solution

In response to the need for more effective, efficient and environmentally sustainable FOG treatment, NCH Europe developed its FreeFlow Liquid range. FreeFlow Liquid provides a powerful biological fluid-based solution to keeping drains and grease traps clean. The traditional lag in liquid bacteria becoming active in the system is reduced as when used alongside NCH Europe's FreeFlow Nutrient and dedicated dispensary system, the liquid is delayed from being dispensed into the water system until the bacteria have become active. When dispensed, the FreeFlow Liquid's live, active bacteria solution begins to feed and digest the FOG and organic waste. This FreeFlow system is much quicker than traditional methods and enzyme-based products, which have often already passed through the built-up area of grease, fats and oils before it starts to take effect. With many products taking three to four hours, or even longer, to become active in the system, FreeFlow Liquid reduces the need for lengthy retention plans. FreeFlow Liquid also works across a much larger range of pH, temperature and oxygen conditions which can be found in a wider array of wastewater systems. The solution is also NSF L2 approved, which is vital for food processing facilities. Maintenance engineers can also save time on replenishment using FreeFlow Liquid. The system is installed with a programmable controller which manages dosage and provides consistent results. Dedicated NCH Europe maintenance staff can also take care of refilling and maintaining the installation, eliminating the need for on-site staff to take responsibility of the system.

Better workflow

In larger wastewater treatment plants and food production facilities, FOG and organic waste build-up can still be a costly issue to contend with. However, it can often be challenging to deliver a consistent, high volume, dosing programme that is both efficient and cost effective. NCH Europe's automated dispensing system, BioAmp, uses the same principles as the FreeFlow Liquid treatment. A computer controls microbial fermentation units, which deliver large amounts of active, naturally occurring, bacteria directly into drains and grease traps. In one application, a large alcoholic beverage producer in the north of the UK recently began using the BioAmp system. Over the course of a one-year period, the facility reduced its wastewater costs by 50%. The following year, it achieved an additional 49% cost reduction.

Building on foundations

The traditional methods of wastewater treatment are no longer the best way to manage modern production plants. To improve the costs and efficiency associated with wastewater management, plant managers need to use the latest technology and treatment solutions.