火电厂燃煤结算煤质加权计算实例

Example of coal quality weighting calculation for coal settlement of thermal power plant

火电厂燃煤结算根据合同期内分批次采样、制样、化验后加权计算质量评定指标,再对照合同条款结算。若加权计算时使用的公式错误则会导致结果错误,从而影响燃料成本结算的准确性。结合具体火电厂合同周期内发热量、全硫、挥发分与燃煤价格的对应关系,简介收到基低位热值、干燥基全硫、干燥无灰基挥发分的加权计算。在煤质加权计算时,应根据不同基准的指标对应不同基准的煤量进行,收到基指标加权计算时与验收净重加权,干燥基指标加权计算时需将验收净重换算至干燥基状态再加权,干燥无灰基指标加权计算时需将验收净重换算至干燥无灰基状态再加权。

In the coal purchase of thermal power plants,the pricing method based on quality is generally adopted,generally taking the received basis low calorific value,dry basis total sulfur and dry ash free basis volatile matter as the quality evaluation index.One way of coal settlement is to sample,prepare samples and test in batches within a contract period,then calculate the quality evaluation index by weighting according to the test results of each batch,and then settle according to the contract terms.In the weighted calculation,the coal quantity of different benchmark should be calculated according to different index benchmark.If the formula used in the weighted calculation is wrong,the result will be wrong and the accuracy of settlement will be affected.When calculating the weight of the received basis low calorific value,the received basis low calorific value and the corresponding acceptance net weight of each batch shall be weighted.When calculating the weight of the dry basis total sulfur,first convert the acceptance net weight of each batch to the dry basis state and then to the dry basis total sulfur of each batch.When calculating the weight of the dry ash free basis volatile fraction,first convert the acceptance net weight of each batch to the dry ash free basis state and then to the dry ash free basis state Weight of dry ash free volatiles of each batch.