What is Wood Chips ?
Woodchips are small- to medium-sized pieces of wood formed by cutting or chipping larger pieces of wood such as trees, branches, logging residues, stumps, roots, and wood waste.
Uses of wood pellets Chips
Woodchips are used primarily as a raw material for technical wood processing. In industry, processing of bark chips is often separated after peeling the logs due to different chemical properties.
Wood pulp
Only the heartwood and sapwood are useful for making pulp. Bark contains relatively few useful fibres and is removed and used as fuel to provide steam for use in the pulp mill. Most pulping processes require that the wood be chipped and screened to provide uniform sized chips.[18]
Mulch
Woodchips are also used as landscape and garden mulch, producing benefits such as water conservation, weed control, reducing and preventing soil erosion, and for supporting germination of native seeds and acorns in habitat restoration projects. As the ramial chipped wood decomposes it improves the soil structure, permeability, bioactivity, and nutrient availability of the soil.Woodchips when used as a mulch are at least three inches thick.
Playground surfacing
Woodchips can be reprocessed into an extremely effective playground surfacing material, or impact-attenuation surface.When used as playground surfacing (soft fall, cushion fall, or play chip, as it is sometimes known), woodchips can be very effective in lessening the impact of falls from playground equipment. When spread to depths of one foot (30 centimetres) playground woodchips can be effective at reducing impacts in falls up to 11 feet (3 meters). Playground woodchips are also an environmentally friendly alternative to rubber-type playground surfaces.
Barbecuing
Woodchips can also be used to infuse flavor and enhance the smoky taste to barbecued meats and vegetables. Several different species of wood can be used depending on the type of flavor wanted. For a mild, sweet fruity flavor, apple wood can be used while hickory gives a smoky, bacon-like flavor. Other different types of wood used are cherry, mesquite and pecan.
Bioreactor
Woodchip piles at the edge of a field can inhibit nitrates from running off into water tiles. They are a simple measure for farmers to reduce nitrate pollution of the watershed without them having to change their land management practice. A 2011 study showed that most of the nitrate removal was due to heterotrophic denitrification.A 2013 experiment from Ireland showed that after 70 days of startup, a woodchip pile loaded with liquid pig manure at 5 L/m2/day removed an average of 90% of nitrate in the form of ammonium after one month. A January 2015 study from Ohio State University showed very low nitrous oxide gas, i.e. greenhouse gas emissions from nitrate transformation under the anaerobic conditions of the woodchip bioreactor. Scientists constructed a model for water flow and nitrate removal kinetics which can be used to design denitrification beds.It is unknown if other nutrients like phosphorus or pathogens are affected by the bioreactor as well.
Fuel
Woodchips have been traditionally used as solid fuel for space heating or in energy plants to generate electric power from renewable energy. The main source of forest chips in Europe and in most of the countries[which?] have been logging residues. It is expected that the shares of stumps and roundwood will increase in the future. As of 2013 in the EU, the estimates for biomass potential for energy, available under current 2018 conditions including sustainable use of the forest as well as providing wood to the traditional forest sectors, are: 277 million m3, for above ground biomass and 585 million m3 for total biomass.
The newer fuel systems for heating use either woodchips or wood pellets. The advantage of woodchips is cost, the advantage of wood pellets is the controlled fuel value. The use of woodchips in automated heating systems, is based on a robust technology.