BHT utilizes two methods of measuring weights collected during waste cooking oil services. A majority of our vacuum trucks have See Level brand gauges on them that measure the gallon volume of waste cooking oil in the vehicles tank. A beginning and ending meter reading is recorded by the driver, from which a net value is derived. The net value is then multiplied x 7.4 pounds to derive the weight collected. For example, if the driver records a beginning meter reading of 100 and an ending meter reading of 258, the net value of 158 will be multiplied by 7.4 and that store will be credited for 1,169 pounds.
An alternative method is utilized on some of our older model and dump type trucks, as well for backup purposes in the event of gauge malfunction. The driver will observe the contents of the grease container and indicate in quarter measures how full the container is. The filled level is then calculated against the overall capacity of the container. For example, if a driver observes that a container is ¾ full and that container has a capacity of 1,560 pounds, that store will be credited for 1,170 pounds.
The rendering of waste cooking oil produces one usable element and several waste elements. Fat is the usable element and is “yielded” as a percentage of the total waste cooking oil volume through the rendering process. Proper waste cooking oil kitchen practices greatly impact the yield.