Bridge-type double-beam grab crane (abbreviation: garbage crane) is the key equipment of the garbage supply system of the municipal solid waste gasification power plant. The garbage crane provides gasifier charging, carrying, stirring and destacking garbage, and stacks them in a predetermined area in order to ensure that the components of the garbage entering the furnace are uniform and combustion is stable. The garbage crane layout design is composed of garbage grab, rolling device, walking device, power distribution device, weighing device and control equipment. Its type is bridge crane, and the crane grab is a multi-petal hydraulic grab. Its design conditions are for heavy-duty operation in dusty air. It has the functions of automatic peeling, metering, pre-alarm and overload protection, and can display various parameters of statistical recording and feeding in the crane control room.
Considerations for the selection of garbage crane
In China, the composition of garbage is complex, the calorific value changes greatly, the calorific value is low, and the moisture is high. In order to ensure the stable combustion of the garbage gasifier, the homogenization of garbage is very important. This process is mainly achieved by garbage cranes and operators.
When selecting a garbage crane, consider the following factors:
1) The bulk density of the compressed garbage in the actual grab may be higher, and the domestic manufacturer chooses 0.55;
2) There must be spare garbage cranes. When any garbage crane is overhauled, the feed hoppers of all garbage gasifiers will not be affected; at the same time, the spare volume should not be too large to avoid waste;
3) The garbage gasifier has a large processing capacity, and the feed hopper has anti-blocking requirements. It requires the garbage grab to be discharged several times, which requires a certain amount of time;
4) The larger the garbage crane, the greater the inertia and the more difficult it is to control;
5) The feeding time and reverse stacking time of each cycle are under full-automatic working conditions. If due to equipment failure, semi-automatic and manual working conditions should also be considered;
6) Consider the rest time of the operator.
Selection process of garbage crane
A garbage gasification power plant processes 800 tons of garbage per day, and sets up a garbage pond to store about 7 days of garbage. The feed rate of the garbage crane is 33.33t / h. The full rate of the hydraulic grab when grabbing garbage is 0.9 ～ 1.0, the design takes 0.9; the bulk density of the uncompressed garbage in the garbage pond is 0.15 ～ 0.30, the bulk density of the compressed garbage in the grab is 0.3 ～ 0.6, the design takes 0.55, Therefore, two 6.3m3 garbage cranes are selected to be arranged on the same floor. A single garbage crane has a lifting capacity of 11t, one for each and one for use. The selected garbage crane should be able to switch manually or semi-automatically.