Stainless steel solution for safe food production

Regular quality assurance inspections are needed to ensure the highest standards for health and safety are met.
Regular quality assurance inspections are needed to ensure the highest standards for health and safety are met.
Select chocolate nibs are extracted from only the freshest cacao fruits in order to produce fine chocolate for use in many recipes.
Select chocolate nibs are extracted from only the freshest cacao fruits in order to produce fine chocolate for use in many recipes.

Paramount in the food and beverage producing industry are the safety, quality and regulatory standards for all products, ingredients and packaging. For Nestlé, setting standards higher than those imposed by the US Food & Drug Administration is viewed as a requirement.

The company, which employs more than 330,000 people worldwide, works closely with its packaging and ingredient suppliers to ensure stringent quality and food safety guidelines are followed. The process begins with a highly coordinated transport and delivery procedure ensuring quality and safety of supplier ingredients prior to production. Once the ingredients arrive at manufacturing locations, they are inspected thoroughly before being approved and accepted into Nestlé’s facilities.

Healthy ingredients

Nestlé believes that in order to provide consumers with healthy products you must begin with healthy ingredients. In an effort to do so while also continuously improving product design, Nestlé utilizes government and internally developed standards which in turn lead to new innovations.

The company’s strict criteria guide all product development and are based on the research and recommendations of the American Academy of Pediatrics, American Heart Association, Food and Drug Administration, United States Department of Agriculture and the National Academy of Science Institute of Medicine.

For one Nestlé manufacturing plant in the northern United States, ensuring environmental safety measures means carefully maintaining several waste streams involved in the plant’s manufacturing process.

In the early stages of production ingredients are washed before being sent to various production and preparation areas. The remaining wastewater must be pumped away and disposed of efficiently while also adhering to strict environmental rules and regulations. 

Nestlé’ sought the assistance of Kerr Pump & Supply in Michigan to choose the right pump for the tough application. Requirements included:

·Erosion resistance: Hard metallurgy would be needed to stand up to course solids including skins, stems, pits and seeds.

·Minimal Footprint and Self Priming: Using vertical wet pit cantilever shaft sump pumps or dry mount self-priming pumps would take up too much floor space but the need for reliable priming remained. Submersible pumps are inherently self-priming and kept cooler by being submerged in the liquid being pumped.

·Non-Clog Design: As the various solids settle they tend to clog pumping action.

·Corrosion Resistance: The pumps needed to be corrosion resistant due to the acidity of the food waste media and clean in place solutions.

·Reliability: Positioned at the bottom of deep sumps, the pumps would cause operational delays if they needed to be constantly pulled for declogging, inspection or maintenance.

Construction strength

Since caustic and acidic solutions were present in the wastewater sumps, construction strength was a key factor. Kerr recommended BJM Pump’s SKX75CSS stainless steel submersible pump with a high grade of cast 316 stainless steel.

The plant also needed to have redundancy and back-up within this particular sump in order to control costly downtime. As a solution, Kerr recommended the installation of three SKX75CSS pumps in the application. The triplex lift station is a blend of three pumps operating in parallel.  

Inherent within the triplex control is the ability to operate one, two or all three pumps at the same time allowing for the changing rate of inflow to the sump. Also, the pumps can alternate in a lead/lag position to promote even wear over their operating life.

In terms of wear resistance all parts exposed to the food waste such as the impeller, wear-plate, oil-housing, pump housing and inner pump top are made of case 316 stainless steel material. When it comes to reliability the submersible motor is protected by double mechanical seals.

Lower seals are made of silicon carbide and the upper seal is constructed from carbon/ceramic. An additional lip seal has been installed above the impeller to help prevent abrasives from entering into the seal chamber. Winding protection and (NEMA) Class F motor insulation allows the motor temperature to rise to 230°F, which is superior to pumps with Class A and B insulation. An automatic switch turns the pump motor off if the temperature and/or amp draw rises too high.

The SKX type pumps produce a shredding action caused by a cutting impeller with a tungsten carbide tip against a suction plate. The suction plate has an irregular opening with engineered cutting slots to help grab debris and aid the impeller with its shredding action. The non-clog, single vane impellers are designed for high volume and lift performance, perfect for the wet well application.

Nestlé installed the triplex system in early 2013 having used BJM stainless steel submersible pumps at the plant since 2008. It continues to innovate within its product range with the pumps providing a safe, reliable platform that is vital to the manufacturing process.