Case Studies
Typical of most banana plantations, this operation left plant litter such as leaves and stalks on the floor of the banana stand in order to decompose and return nutrients to the soil to support new growth. However, it takes significant time for this litter to decompose or “compost” slowing the availability of needed nutrients.
The grease traps and lagoon treatment system at this dairy beverage plant was severely overloaded with the high-organic dairy waste. Grease and other solids covered the surface of the lagoon and odors were intolerable, saturating clothing, and eliciting numerous complaints from surrounding neighborhoods. Biological treatment was poor as confirmed by microscopic exam that showed a high population of worms and solids that would not be present in an active biomass.
A major full service bakery in Northern Ohio has a pretreatment plant which discharges to the local village wastewater treatment plant. The average daily flow through this plant is 15,000 to 25,000 per day. Influent waste concentration ranges from 6,000 to 100,000 mg/l CBOD; average suspended solids is 6,000 mg/l; and FOG level ranges between 800 mg/l to 1,000 mg/l.
A small cheese factory with an activated sludge system was experiencing high levels of sulfide and mercaptan odors, high solids that clogged sand filters, and poor settling in their clarifier. All these problems were signs of inadequate treatment efficiency. Their 10,000-gallon daily flow was discharged to a 140,000-gallon aerobic digester, which then decanted to a clarifier where significant polymer addition was required to achieve settling.
The facility is a rendering plant, utilizing a limited waste water system. The basic design has a cooling tower, from which the water passes through a grease trap and then into an aeration tower. The water is then discharged into a series of three small lagoons, with a retention time that is calculated to be between 10 and 15 days based on a system volume of 110,000 gallons in the tanks and lagoons and the flow which was believed to vary between 6,857and 11,428 gallons per day.
Dion Vandewiele N.V. has engaged in the production of pasteurized liquid egg products since 1937. Between 3 and 4 million eggs are broken daily, 5 days a week, to produce egg-white, egg-yolk, and some mixed egg products for a total to 900- 1000 tons of end products per week.