CHIP HANDLING CHIP STORAGE CHIP QUALITY

THE CHIP YARD

WOOD PREPARATION FOR PULPING WOOD PREPARATION CONSISTS OF A SERIES OF OPERATIONS WHICH CONVERTS LOGS INTO A FORM WHERE THEY CAN BE EASILY PULPED. PROCESSFORM PROCESS FORM GROUNDWOOD SHORT BLOCKS CHEMICAL CHIPS NONWOODS BALES

WOOD PREPARATION FOR PULPING WOOD PREPARATION CONSISTS OF A SERIES OF OPERATIONS WHICH CONVERTS LOGS INTO A FORM WHERE THEY CAN BE EASILY PULPED. PROCESSFORM PROCESS FORM GROUNDWOOD SHORT BLOCKS CHEMICAL CHIPS NONWOODS BALES

WOOD PREPARATION FOR PULPING WOOD PREPARATION CONSISTS OF A SERIES OF OPERATIONS WHICH CONVERTS LOGS INTO A FORM WHERE THEY CAN BE EASILY PULPED. PROCESSFORM PROCESS FORM GROUNDWOOD SHORT BLOCKS CHEMICAL CHIPS NONWOODS BALES

WOOD PREPARATION FOR PULPING WOOD PREPARATION CONSISTS OF A SERIES OF OPERATIONS WHICH CONVERTS LOGS INTO A FORM WHERE THEY CAN BE EASILY PULPED. PROCESSFORM PROCESS FORM GROUNDWOOD SHORT BLOCKS CHEMICAL CHIPS NONWOODS BALES WOULD SUPERIOR QUALITY WOOD (MAHOGANY, CHERRY OR WALNUT) BE CHIPPED FOR PULPING? WHY? ____________________

TRANSPORTING LOGS TO THE CHIP YARD WHAT ARE THE MODES OF TRANSPORTATION USED TO BRING LOGS TO CHIP YARDS? WICH TYPE IS THE MOST PREDOMINANT? TRUCKS RAIL BARGES/RIVER AIR

CHIP YARD PROCESSING STEPS

Weighed CHIP YARD PROCESSING STEPS

Weighed Unloaded CHIP YARD PROCESSING STEPS

Weighed Unloaded Piled CHIPYARD PROCESSING STEPS

Weighing Unloading Piled Slasher deck – Big saw to cut to manageable lengths CHIP YARD PROCESSING STEPS

Weighing Unloading Piled Slasher deck – Big saw to cut to manageable lengths Debarking knock off bark & dirt CHIP YARD PROCESSING STEPS

Weighing Unloading Piled Slasher deck – Big saw to cut to manageable lengths Debarking knock off bark & dirt Chipping reduces logs to chips CHIPYARD PROCESSING STEPS

Weighing Unloading Piled Slasher deck – Big saw to cut to manageable lengths Debarking Chipper reduce to chips Screening - classify to size CHIPYARD PROCESSING STEPS

Weighing Unloading Piled Slasher deck – Big saw to cut to manageable lengths Debarking knock off bark & dirt Chipper reduces logs to chips Screening - classify to size Store and haul away CHIPYARD PROCESSING STEPS

EQUIPMENT SPECIFICS DEBARKING CHIPPING

TWO MAJOR TYPES OF DEBARKERS MECHANICAL Principal of operation: Log to log friction created by rotating drum barker or debarking drum. Most common are the dry and wet methods. HYDRAULIC High pressure water jets

DEBARKING DETAILED

CHIPPER

SCREENING

The Chip screen generally is made up of a number of vibrating screen plates used to classify the chips. The chips are fed onto the primary screen plate evenly and the Smaller sized chips pass through to the second stage. The oversize chips stay above the plate and are rejected for further processing. The accepted chips that passed through the plate then pass through further plates of smaller hole size until only the fines and undersize chips pass through into the reject area.

CHIP SIZE

WHAT WASTE PRODUCTS ARE GENERATED AT A CHIPYARD? WHAT IS DONE WITH THEM?

WASTE PRODUCTS GENERATED AT A CHIP YARD BARK SAWDUST

WASTE PRODUCTS GENERATED AT A CHIP YARD BARK –Landscape mulch –Burning fuel –Filler in board SAWDUST –Boiler feed –Building products like particle board

QUALITY CONTROL AT THE CHIP YARD What quality tests were run at Powell? Weight (incoming logs) Hardwood or softwood “Bad” specie types What else do you think they run or check for? Size Thickness Bark Sawdust

CHIP CONTAMINANTS TYPE CONTAMINATION PROBLEM CREATED Dirt and foreign material Visible pulp and paper contaminant paper/pulp Oversized chips Fines Bark and burnt wood Handling issues/High screen rejects/Doesn’t cook out well and the partly cooked pulp is rejected by the pulp mill screens Lower yield/Lowers pulp/paper strength Causes circulation problems in digester Pin Chips Lower yield/Lowers pulp/paper strength Hickory Walnut Bark too hard/tight – Can’t debark Stains / Can’t bleach out

WATER/SPRINKLER USES AT A CHIP YARD

NOW THAT WE HAVE PRODUCED, TESTED, AND INSPECTED THE CHIPS, HOW DO WE GET THEM TO THE PAPER MILL? Truck Rail Barges

TRUCK UNLOADING

RAILCAR UNLOADING

METHODS OF MOVING CHIPS AT THE MILL SITE

CHIP STORAGE

BAD THINGS CAN HAPPEN DURING CHIP STORAGE What is chip degradation? When chips go bad due to rot, decay, decomposition. Breaking down. What causes it? Usually micro organisms, bacteria, mold, fungus. When those little bugs get together, feed on the chips, The chips become weaker, may be discolored, can lead to heat (thermal) build up and possibly start a fire.

TERMS TO REMEMBER Chip degradation Fungal build up Thermal build up Spontaneous combination FIFO

Impact of Degradation Affects mill profitability due to lower pulp yield, quality, strength, and brightness Considerable reduction in the value of the end product Weakening in fiber strength Lower yield of by products (such as tall oil and turpentine) Changes in chip extractives affect the cooking and recovery process. Extractives can cause non uniform cooking because it has varying amounts of other substances in it like resins, pitch, etc. (Loss of wood extractives are very rapid over the first two months of storage.) Reduced pulping yield is the most significant consequence of woodchip deterioration from outside chip storage Pitch build-up Slime build-up

WHAT CAN BE DONE TO MINIMIZE THE NEGATIVE EFFECTS OF DEGRADATION? Chip deterioration is a function of ……….TIME The longer the chips hang around, the greater the chance of degradation. The most effective way to minimize chip deterioration is to ………..REDUCE STORAGE TIME Chip piles should be built (set up) on a FIFO basis to avoid the infection of fresh chips by old or contaminated chips. FIRST IN FIRST OUT

RAIL UNLOADING